JP2003268660A - Ultrafine fiber-dispersed nonwoven fabric, sheet material, production method and production apparatus thereof - Google Patents

Abstract

(57) Abstract: An ultrafine fiber-dispersed nonwoven fabric having a low degree of close contact between ultrafine fibers and a uniform formation, a sheet material containing the ultrafine fiber-dispersed nonwoven fabric, and a method and apparatus for producing the same are provided. An ultrafine fiber-dispersed nonwoven fabric contains ultrafine fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less in a dispersed state, an adhesion rate of attached matter of 0.5 mass% or less, and a main correlation coefficient of formation. Is less than or equal to the value of α obtained from the following equation. α = 4.6692 × W− ^0.7222 (where W is the basis weight of the nonwoven fabric dispersed with fine fibers (g / m ² )) In the manufacturing method, an aggregate of the fine fibers is ejected from a nozzle into a gas by the action of a compressed gas. A step of generating and dispersing ultrafine fibers by colliding with a collision member having a projection,
A step of forming a fiber web by accumulating the dispersed ultrafine fibers, and a step of bonding the fiber web.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an ultrafine fiber-dispersed nonwoven fabric,
The present invention relates to a sheet material, a manufacturing method and a manufacturing apparatus for these.

[0002]

2. Description of the Related Art Nonwoven fabrics can be given various functions by appropriately combining the constituent fibers, the method for forming the fiber webs, and the method for joining the fiber webs, and are therefore applied to various purposes.

For example, a non-woven fabric made of ultrafine fibers having a fiber diameter of 4 μm or less has excellent filtering performance, and thus can be suitably used as a filter or mask for liquid or gas. Further, it can be preferably used as a battery separator or a wiping cloth by utilizing the property of having a small pore size or a high liquid retention property.

As one method for producing a non-woven fabric composed of ultrafine fibers having a fiber diameter of 4 μm or less, it is difficult to dissolve and remove a resin component (sea component) which can be dissolved and removed in a solvent into this solvent. Using a fiber (so-called sea-island type fiber) in which various resin components (island components) are dispersed, a fiber web is formed by the card method or air-laying method, and then the fibers are entangled by the action of a needle or a water stream. After forming the composite fiber web, there is a method of dissolving and removing the sea component of the sea-island type fiber with a solvent to generate ultrafine fibers composed of the island component. According to this method, a nonwoven fabric composed of ultrafine fibers having a fiber diameter of 4 μm or less can be produced, but since the ultrafine fibers are in a bundle and there is not much difference from thick fibers, filtration performance and flexibility It was insufficient in terms of sex. In addition, a bundle of ultrafine fibers is conspicuous, or streaks due to entanglement occur,
The texture was not uniform and looked bad.

As a method for producing a non-woven fabric which eliminates the state where the ultrafine fibers are bundled, the ultrafine fibers are made up from a slurry in which the ultrafine fibers having a fiber diameter of 4 μm or less are dispersed to form a fiber web. Later, there is a method of bonding the fibrous webs.

[0006]

According to this method, a nonwoven fabric in which ultrafine fibers are dispersed can be obtained. However, a fiber web formed by drawing ultrafine fibers from a slurry has an apparent appearance in which the fibers are in close contact with each other. Due to its high density, it may not be applicable to various applications. For example, when used as a filter, the pressure loss was high.

The present invention has been made to solve the above-mentioned conventional problems, and is an ultrafine fiber-dispersed nonwoven fabric in which ultrafine fibers are dispersed, and the degree of adhesion of ultrafine fibers to each other is high. An object of the present invention is to provide an ultrafine fiber-dispersed nonwoven fabric having a low texture and uniform texture, a sheet material containing the ultrafine fiber-dispersed nonwoven fabric, a method for producing the same, and an apparatus for producing the same. As a result of earnest research by the present inventors, the high apparent density of the fiber web formed from the slurry is due to the use of a surfactant to disperse the ultrafine fibers or to fix the ultrafine fibers together. For this reason, since a sizing agent is used, the surface active agent or sizing agent adheres to the surface of the ultrafine fibers, and the surface active agent or sizing agent that adheres has the effect of increasing the adhesion between the ultrafine fibers. , And the solvent (for example, water) in which the ultrafine fibers are dispersed is removed when the fiber web is formed by making it from the slurry, and the solvent is removed by moving in the thickness direction of the fiber web. Therefore, it has been found that as the solvent moves, the ultrafine fibers are easily arranged and arranged in a direction orthogonal to the thickness direction of the fiber web. The present invention has been made based on such findings.

[0008]

The ultrafine fiber-dispersed nonwoven fabric of the present invention has at least a fiber diameter of 4 μm or less and a fiber length of 3 or less.
An ultrafine fiber-dispersed non-woven fabric that contains ultrafine fibers of mm or less in a dispersed state and has an attachment rate of 0.5 mass% or less, and from the brightness information of reflected light when light is irradiated on at least one surface. An ultrafine fiber-dispersed nonwoven fabric, wherein the calculated absolute value of the main correlation coefficient of texture is not more than the value of α obtained from the following equation. α = 4.6692 × W ^−0.7222 (where W is the weight of the ultrafine fiber-dispersed nonwoven fabric (g / m ² )) ”
Is. When the ultrafine fiber-dispersed nonwoven fabric having this characteristic is particularly described, it is referred to as "nonwoven fabric A". In the "nonwoven fabric A" of the present invention, since the amount of the deposit such as the surfactant and the sizing agent is extremely small, the adhesion between the ultrafine fibers becomes low. Therefore, the ultrafine fiber-dispersed nonwoven fabric of the present invention can be applied to various applications such as having a proper amount and size of voids and reducing pressure loss. In addition, in the “nonwoven fabric A” of the present invention,
Since ultrafine fibers are in a dispersed state, not in a bundled state, various characteristics (filterability,
Flexibility, etc., and the absolute value of the main correlation coefficient of the texture is less than the value of α obtained from the above formula, that is, the texture is highly uniform and the appearance is good even at low and high basis weights. It is something.

The present invention also provides that "at least the fiber diameter is 4
A microfiber-dispersed nonwoven fabric containing microfibers having a fiber length of 3 μm or less and a deposition rate of 0.5 mass% or less in a dispersed state, wherein at least one surface is irradiated with light. An ultrafine fiber-dispersed nonwoven fabric, wherein the absolute value of the main correlation coefficient of the texture calculated from the luminance information of the reflected light is less than or equal to the value of α obtained from the following equation. α = 4.6692 × W ^−0.7222 (where W is the weight of the ultrafine fiber-dispersed nonwoven fabric (g / m ² )) ”
Also related to. Such an ultrafine fiber-dispersed nonwoven fabric is referred to as "nonwoven fabric B" in order to distinguish it from the above-mentioned "nonwoven fabric A". In the “nonwoven fabric B” of the present invention, the amount of the extraneous fibers such as a surfactant and a sizing agent is extremely small, and the adhesion between the ultrafine fibers is low, so that it can be applied to various applications. Further, also in the “nonwoven fabric B” of the present invention,
Since ultrafine fibers are in a dispersed state, not in a bundled state, various characteristics (filterability,
Flexibility, etc., and the absolute value of the main correlation coefficient of the texture is less than the value of α obtained from the above formula, that is, the texture is highly uniform and the appearance is good even at low and high basis weights. It is something.

In the present specification, "nonwoven fabric A"
And "nonwoven fabric B" are meant to mean "nonwoven fabric A,
The fiber constituting the non-woven fabric A is referred to as “fiber A”, the fiber constituting the non-woven fabric B is referred to as “fiber B”, and both fibers A and B are referred to as “fiber B”. "Fiber A, B", the fibrous web from which the non-woven fabric A is based is referred to as "Fiber web A", and the fibrous web from which the non-woven fabric B is based is referred to as "Fiber web B". And “fiber web B” are referred to as “fiber webs A and B”.

Furthermore, the sheet material of the present invention is a sheet material containing at least one layer of the above-mentioned "nonwoven fabric A" or "nonwoven fabric B". Therefore, the sheet material can exhibit the performance of the nonwoven fabric A or the nonwoven fabric B.

The method for producing the non-woven fabric A of the present invention is described as follows: "A group of ultrafine fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, or a group of these fibers and / or mechanically divided fibers. Distributable fibers capable of generating ultrafine fibers having a diameter of 4 μm or less and a fiber length of 3 mm or less, or an aggregate thereof, are ejected into the gas from a nozzle by the action of compressed gas, and are provided in front of the nozzle ejection port. The micro-fiber assembly or a group of the micro-fiber aggregates into microfibers, and / or
Or a step of dividing the splittable fiber or an aggregate thereof into ultrafine fibers, and dispersing the ultrafine fibers,
A method for producing an ultrafine fiber-dispersed nonwoven fabric, comprising: a step of accumulating dispersed ultrafine fibers on an accumulating member to form a fiber web; and a step of binding the fiber web. It is. As described above, in the method for producing the nonwoven fabric A of the present invention, the solvent is not used as the medium for dispersing the ultrafine fibers A as in the prior art, but the ultrafine fibers A are dispersed in the gas. Therefore, the solvent is used as the dispersion medium. In that case, it is not necessary to use a surfactant or a sizing agent, which is necessary. Therefore, the non-woven fabric A having an attachment rate of 0.5 mass% or less attached to the non-woven fabric A in which the ultra-fine fibers A are dispersed, that is, the extra-fine fibers A
The non-woven fabric A having a low degree of adhesion can be easily manufactured. Further, an ultrafine fiber A aggregate (particularly, a bundle-like aggregate of the ultrafine fibers A) or an aggregate group thereof, and / or
The ultrafine fiber-producible splittable fibers A or their aggregates are ejected into the gas from the nozzle by the action of the compressed gas, and are made to collide with a collision member having a projection to be dispersed, whereby the ultrafine fiber A aggregates or The aggregate group is divided into ultrafine fibers A and / or splittable fibers A
Alternatively, since the aggregate is divided into the ultrafine fibers A and the ultrafine fibers A are dispersed to produce the nonwoven fabric A, the ultrafine fibers A are sufficiently dispersed and the nonwoven fabric A having a uniform texture is easily produced. can do.

The method for producing the nonwoven fabric B of the present invention is as follows: "A group of ultrafine fibers having a fiber diameter of 4 μm or less, a fiber length of 3 mm or less, and an attachment rate of 0.5 mass% or less, or an assembly thereof. Body group and / or mechanically divided to have a fiber diameter of 4 μm or less and a fiber length of 3 mm or less,
In addition, the splittable fibers capable of generating ultrafine fibers having an attachment rate of 0.5 mass% or less or an aggregate thereof are ejected from the nozzle into the gas by the action of the compressed gas, By colliding with a collision member having a projection provided in the front, the ultrafine fiber aggregate or the aggregate group thereof is divided into ultrafine fibers, and / or the splittable fiber or the aggregate thereof is divided into ultrafine fibers. And a step of dispersing the ultrafine fibers, a step of accumulating the dispersed ultrafine fibers on an accumulating member to form a fibrous web, and a step of binding the fibrous web together, the ultrafine fibers. A method for manufacturing a dispersed nonwoven fabric. It is. Thus, in the method for producing the nonwoven fabric B of the present invention,
Since the ultrafine fibers B are dispersed in a gas without using a solvent as a medium for dispersing the ultrafine fibers B as in the conventional case, a surfactant or a sizing agent necessary when the solvent is used as a dispersion medium is used. You don't have to. Further, since the attachment rate of the deposits on the ultrafine fibers B is low, the ultrafine fibers B are easily charged and the ultrafine fibers B are easily repelled from each other. Therefore, the non-woven fabric B having a low degree of adhesion of the ultrafine fibers B can be easily manufactured. Further, as in the case of the non-woven fabric A, due to the action of the collision member having the protrusions, the ultra-fine fibers B are sufficiently dispersed, and the non-woven fabric B having a uniform and good texture can be easily manufactured.

The sheet material manufacturing method of the present invention is
In the method for producing the non-woven fabric A or the non-woven fabric B, the ultra-fine fibers A or the ultra-fine fibers B are placed on the "auxiliary layer" instead of accumulating the dispersed ultra-fine fibers A or the ultra-fine fibers B on the accumulating member.
And a step of combining the fiber webs A and B with each other, and also combining the fiber webs A and B with an auxiliary layer. According to this method, a uniform and well-formed sheet material having the nonwoven fabric layer A or the nonwoven fabric layer B and the auxiliary layer can be easily manufactured in a series of steps for producing the nonwoven fabric fabric A or the nonwoven fabric fabric B.

The production apparatus of the present invention comprises: (1) an aggregate of ultrafine fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, or a group of these aggregates, and / or mechanically dividing the fiber diameter. Having a diameter of 4 μm or less and a fiber length of 3 mm or less, splittable fibers capable of generating ultrafine fibers, or an aggregate of the splittable fibers can be ejected into the gas by the action of compressed gas, (2) Compressed gas to the nozzle Means for supplying (3) a collision member having a protrusion provided in front of the nozzle ejection port, (4) an aggregate of the ultrafine fibers or a group of these aggregates, and / or an ultrafine fiber-producible splitting property A dispersion chamber in which fibers or their aggregates are ejected from the nozzle into the gas by the action of compressed gas, and the ultrafine fibers generated by collision with the collision member are dispersed in the gas,
(5) An accumulation member for accumulating the ultrafine fibers dispersed in the gas in the dispersion chamber, and (6) means for coupling the web accumulated on the accumulation member,
Ultrafine fiber dispersed nonwoven fabric manufacturing equipment. It is possible to manufacture the nonwoven fabric A, the nonwoven fabric B, or the sheet material of the present invention.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The nonwoven fabrics A and B of the present invention have a fiber diameter of 4 μm so that they are excellent in various characteristics such as filterability and flexibility.
It contains ultrafine fibers A and B having a fiber length of 3 mm or less and a length of m or less. Since the smaller the fiber diameter of the ultrafine fibers A and B, the better the various characteristics, the fiber diameter of the ultrafine fibers A and B is preferably 3 μm or less, and more preferably 2 μm or less. Generally, the finer the fiber diameter, the more easily the ultrafine fibers A and B become entangled, and it becomes difficult to uniformly disperse the fibers, and the advantage of containing the ultrafine fibers A and B can be obtained. Although difficult, in the nonwoven fabrics A and B of the present invention, since the ultrafine fibers A and B are uniformly dispersed, as the fiber diameters of the ultrafine fibers A and B become smaller,
The various characteristics described above are improved. The lower limit of the fiber diameter of the ultrafine fibers A and B is not particularly limited, but 0.01 μm
m is suitable. The "fiber diameter" in this specification is
When the cross-sectional shape of the fiber is circular, it means the diameter thereof, and when the cross-sectional shape of the fiber is non-circular, it means the diameter of a circle having the same cross-sectional area and area.

The ultrafine fibers A and B contained in the nonwoven fabrics A and B of the present invention have a fiber length of 3 m so that they have excellent dispersibility.
m or less. That is, when the ultrafine fibers A and B have a fiber length of more than 3 mm, the degree of freedom of the ultrafine fibers A and B is low and the dispersibility is reduced. More preferable fiber length is 2 mm
It is the following. The lower limit of the fiber length of the ultrafine fibers A and B is not particularly limited, but about 0.1 mm is suitable. Further, it is preferable that the ultrafine fibers A and B are cut so that the fiber length is uniform. The “fiber length” in the present invention means a length obtained by JIS L 1015 (chemical fiber staple test method) B method (corrected staple diagram method).

The ultrafine fibers A and B used in the present invention can be composed of any component (for example, an organic component or an inorganic component). For example, a polyamide resin, a polyvinyl alcohol resin, a polyvinylidene chloride resin, Polyvinyl chloride resin, polyester resin, polyacrylonitrile resin, polyolefin resin (for example, polyethylene resin, polypropylene resin, etc.), polystyrene resin (for example, crystalline polystyrene, amorphous polystyrene, etc.), aromatic It may be composed of an organic component such as a polyamide resin or a polyurethane resin, or an inorganic component such as glass, carbon, potassium titanate, silicon carbide, silicon nitride, zinc oxide, aluminum borate, wollastonite, or the like. In general, when the ultrafine fibers A and B are made of an organic component, they have lower rigidity and are softer than when they are made of an inorganic component. However, it becomes difficult to obtain the advantage of containing the ultrafine fibers A and B. However, in the nonwoven fabrics A and B of the present invention, the ultrafine fibers A and B are uniformly dispersed. The advantage (for example, bulkiness, texture, or elasticity) of being composed of an organic component can be improved.

In order to maintain the nonwoven fabric form of the nonwoven fabrics A and B according to the present invention, it is necessary that the fibers are bonded to each other. However, if the ultrafine fibers A and B can be fused,
It is preferable that the non-woven fabric form can be maintained by fusing B and the ultrafine fibers A and B are unlikely to fall off. In the fusible ultrafine fibers A and B, at least a part of components constituting the surfaces of the ultrafine fibers A and B can be made of a thermoplastic resin. For example, the components constituting the surfaces of the ultrafine fibers A and B are polyolefin resin (for example, polyethylene resin, polypropylene resin, etc.), polyvinylidene chloride resin, polyester resin, polyamide resin, crystalline polystyrene resin, etc. Or a non-crystalline thermoplastic resin such as a polyvinyl chloride-based resin, an amorphous polystyrene-based resin, a polyacrylonitrile-based resin, or a polyvinyl alcohol-based resin.

When the fusible ultrafine fibers A and B are composed of two or more types of components, even if one type of component is fused, the fiber form can be maintained by at least one type of component. It is preferable because it is possible. The cross-sectional shape of the ultrafine fibers A and B in the case of being composed of two or more kinds of components may be, for example, a core-sheath type, an eccentric type, a sea-island type, a side-by-side type, a multiple bimetal type, or an orange type. it can.

The ultrafine fibers A and B used in the present invention are made of the respective ultrafine fibers A and B so that the texture of the nonwoven fabrics A and B is excellent.
However, it is preferable that the diameter does not substantially change in the fiber axis direction (that is, they have substantially the same diameter). As described above, the ultrafine fibers A and B of the individual ultrafine fibers A and B, which have substantially the same diameter in the fiber axis direction and do not change, are, for example, island components which are regulated in the sea component at the spinneret part. It can be obtained by removing the sea component of the sea-island type fiber obtained by the composite spinning method of extruding and compounding. Typically,
When the sea component of the sea-island type fiber is removed to form the ultrafine fibers A and B, each of the ultrafine fibers A derived from the island component,
Since B exists as a bundle-like aggregate and the ultrafine fibers A and B are close to each other, they tend to be entangled and it becomes difficult to disperse them uniformly. Therefore, the advantage of containing the ultrafine fibers A and B is Although it is difficult to obtain, in the nonwoven fabrics A and B of the present invention, even the bundle-like aggregates of the ultrafine fibers A and B are uniformly dispersed. Therefore, the advantage of containing the ultrafine fibers A and B is advantageous. Can be obtained.

The ultrafine fibers A and B used in the present invention may be in an unstretched state, but are preferably in a stretched state so that they are excellent in strength.

Ultrafine fibers B constituting the nonwoven fabric B of the present invention
Has a very small adhesion rate of 0.5% by mass or less of the adhered matter (surfactant, sizing agent, etc.) adhered to the ultrafine fibers B, and it is difficult for the ultrafine fibers B to adhere to each other. The smaller the adherence rate of the adhered matter, the more excellent the above-mentioned effect. Therefore, the adherence rate is preferably 0.3 mass% or less,
More preferably, it is 0.1 mass% or less, even more preferably 0.08 mass% or less, even more preferably 0.
06 mass% or less, and even more preferably 0.04 ma
It is ss% or less, and even more preferably 0.02 mass% or less. The deposition rate of the deposit in the present invention refers to the percentage of the mass of the deposit with respect to the mass of the object (for example, the ultrafine fiber B, the nonwoven fabric A). That is, it means the value obtained by the following formula. A = (ms / mf) × 100 Here, A means the adherence rate (%) of the adhering matter, ms means the adhering mass (g) of the adhering matter, and mf means the mass (g) of the object. In addition, the “adhered matter” in the present specification refers to an extract (hereinafter, referred to as “an attached matter” obtained by immersing an object in hot water (for example, hot water at a temperature of 80 ° C. to 100 ° C.) for 15 minutes.
Both hot water extract) and an extract obtained by immersing the object in a hot methanol solution for 15 minutes (hereinafter referred to as hot methanol extract). Examples of hot water extracts include sizing agents (for example, acrylamide, sodium polyacrylate, sodium polyalginate, polyethylene oxide, methyl cellulose, carboxymethyl cellulose, hydroxymethyl cellulose, polyvinyl alcohol, etc.), and hot methanol extracts include surfactants ( There are compounds having both a hydrophilic group and a lipophilic group, for example, nonionic surfactants. In the nonwoven fabrics A and B of the present invention, at least the individual ultrafine fibers A and B as described above are dispersed, and therefore the ultrafine fibers A and
The effect of including B can be exhibited. The content of the ultrafine fibers A and B is preferably 20 mass% or more, and more preferably 50 mass% or more so that the effect of containing the ultrafine fibers A and B can be exhibited.

In the nonwoven fabrics A and B of the present invention, other than the above-mentioned ultrafine fibers A and B (1) Fibers A and B having a fiber diameter of 4 μm or less and a fiber length of more than 3 mm (hereinafter, ultrafine long fibers A and B) (2) Fibers A and B having a fiber diameter of more than 4 μm and 50 μm or less and a fiber length of 10 mm or less (hereinafter, thick fibers A and B)
(3) Any material selected from powders can be mixed with the ultrafine fibers A and B alone or in combination.
Among the fibers A and B of (1) and (2), it is preferable to use the thick fibers A and B. If the thick fibers A and B are too long, the dispersed state of the fibers tends to be insufficient. Therefore, the fiber length of the thick fibers A and B is preferably 10 mm or less, more preferably 5 mm or less, and further preferably 3 mm or less. preferable. In addition, it is preferable that the product is cut into such a length so that the length is uniform. The lower limit is not particularly limited, but about 0.1 mm is suitable.

The thick fibers A and B can also be composed of the same components as the ultrafine fibers A and B. That is, for example, polyamide resin, polyvinyl alcohol resin,
Polyvinylidene chloride resin, polyvinyl chloride resin, polyester resin, polyacrylonitrile resin, polyolefin resin (for example, polyethylene resin, polypropylene resin, etc.), polystyrene resin (crystalline polystyrene, amorphous polystyrene, etc.) ), Organic components such as aromatic polyamide resins and polyurethane resins, glass, carbon, potassium titanate, silicon carbide, silicon nitride,
It can be composed of an inorganic component such as zinc oxide, aluminum borate, and wollastonite.

When the thick fibers A and B can be fused, the thick fibers A and B can be fused to maintain the non-woven fabric form of the nonwoven fabrics A and B according to the present invention. In the fusible thick fibers A and B, at least a part of the components constituting the surfaces of the thick fibers A and B can be made of a thermoplastic resin. For example, the components constituting the surfaces of the thick fibers A and B are polyolefin resin (for example, polyethylene resin, polypropylene resin, etc.), polyvinylidene chloride resin, polyester resin, polyamide resin, crystalline polystyrene resin, etc. Or a non-crystalline thermoplastic resin such as a polyvinyl chloride-based resin, an amorphous polystyrene-based resin, a polyacrylonitrile-based resin, or a polyvinyl alcohol-based resin.

If the fusible thick fibers A and B are composed of two or more kinds of components having different melting points, even if one kind of constituent is melted, at least one kind of other constituents causes the fiber form. It is preferable because the above can be maintained. When the thick fibers A and B are composed of two or more kinds of components, the cross-sectional shapes of the thick fibers A and B are, for example, a core-sheath type, an eccentric type, a sea-island type, a side-by-side type, a multiple bimetal type, and an orange. Can be a mold.

The thick fibers A and B may be in an unstretched state, but are preferably stretched so that they are excellent in strength. Two or more types of thick fibers A and B having different fiber diameters, fiber lengths, and / or components may be mixed. Further, the thick fibers A and B can be used as in the case of the ultrafine fibers B, even if the attachment rate of the deposit is low or the attachment rate of the deposit is high. In the case of the non-woven fabric A, it is necessary to use the thick fibers A such that the adherence rate of the deposit on the non-woven fabric A is 0.5 mass% or less. Therefore, the thick fibers A constituting the non-woven fabric A have a low adherence rate of deposits (0.5 mass% or less, 0.3 mass% or less, like the ultrafine fibers B).
% Or less, 0.1 mass% or less, 0.08 mass% or less, 0.06 mass% or less, 0.04 mass% or less, and 0.02 mass% or less are preferable).

The powder that can be used to form the nonwoven fabrics A and B of the present invention may be organic powder or inorganic powder, and is not particularly limited. Various functional powders may be used to add various functions to the nonwoven fabrics A and B. For example, deodorant powder, deodorant powder, ion exchange resin powder, heavy metal adsorption powder, low-molecular chemical removal powder (catalyst that can adsorb or inactivate a trace amount of low-molecular substances (solvents, oligomers, etc.)) , Degassed powder (catalyst capable of adsorbing or inactivating a trace amount of gaseous impurities), adhesive powder and the like. The functional powder may be supplied to the nozzle together with the fibers A and B and / or the aggregate of the fibers A and B, and may be mixed and fixed when forming the fiber webs A and B. Functional powder may be added to the fiber webs A and B and fixed. When the functional powder is supplied to the nozzle together with the fibers A and B and / or the fiber A and B aggregates as in the former, the fibers A and B
The functional powder is held by B and can be prevented from falling off without using a binder or the like, so that the original function of the functional powder can be exhibited.

In the nonwoven fabrics A and B of the present invention, since the ultrafine fibers A and B as described above are dispersed and contained, various characteristics can be exhibited by including the ultrafine fibers A and B. it can. That is, since the ultrafine fibers A and B do not exist in a bundled state, various characteristics due to the inclusion of the ultrafine fibers A and B can be exhibited.

In the non-woven fabric A of the present invention, the adhesion rate of the adhered matter (surfactant, sizing agent, etc.) adhered to the "non-woven fabric A" is 0.5 so that the ultrafine fibers A and B are unlikely to adhere to each other.
It is an extremely small amount of not more than mass%. The smaller the adherence rate of the adhered matter, the more excellent the effect is. Therefore, the adherence rate is preferably 0.3 mass% or less, more preferably 0.1 mass% or less, still more preferably 0.08 mass% or less. , And even more preferably 0.0
6 mass% or less, and even more preferably 0.04 mass
s% or less, and even more preferably 0.02 mass% or less.

In the "nonwoven fabric A" of the present invention,
The small amount of deposits has a secondary effect that the probability of generating contaminants is extremely low. This has great significance in applications where pollutants are a problem, such as filter media applications and battery separators.

The ultrafine fibers A used in the present invention are used to form a fiber web A using a surfactant or a sizing agent, for example, by a wet method, and a water stream or the like is applied to the fiber web A. Even if it is done, the adhesion rate of the adhered matter is 0.5
It is difficult to manufacture the nonwoven fabric A having a mass% or less.

The "nonwoven fabric A" of the present invention does not have to be a single layer, and may contain two or more layers containing the ultrafine fibers A dispersed therein. When two or more layers in which the ultrafine fibers A are dispersed are provided, various characteristics can be imparted. For example, the filtration performance can be improved by providing two or more layers in which the ultrafine fibers A having different amounts of the ultrafine fibers A are dispersed.

In the "nonwoven fabric B" of the present invention,
Since the adhesion rate of the adhered matter adhered to the ultrafine fibers B is low and the adhesion of the fibers B is low, it can be applied to various applications.
Also, in the “nonwoven fabric B”, since the ultrafine fibers B are not in a bundled state but in a dispersed state, various characteristics (filterability, flexibility, etc.) due to the inclusion of the ultrafine fibers B, and The texture is also excellent.

The "nonwoven fabric B" of the present invention does not have to be a single layer, and may include two or more layers containing the ultrafine fibers B dispersed therein. When two or more layers in which the ultrafine fibers B are dispersed are provided, various characteristics can be imparted. For example, the filtration performance can be enhanced by providing two or more layers in which the ultrafine fibers B having different amounts of the ultrafine fibers B are dispersed.

The apparent density of the fibrous webs A and B of the nonwoven fabrics A and B of the present invention before binding the fibers A and B is 0.005 because the ultrafine fibers A and B are not in close contact with each other.
It can also have a very low apparent density of g / cm ³ . The apparent density of the fiber webs A and B of the present invention is
It can be about 0.005 to 0.1 g / cm ³ . The "apparent density" in the present invention is the basis weight (g / c
m ² ) is the value obtained by dividing the thickness (cm).
The value of mass per unit area measured by the method defined in IS L1085: 1998.6.2, "thickness"
Indicates a value obtained by the A method defined in JIS L1085: 1998.6.1 (thickness). Since the non-woven fabrics A and B of the present invention are obtained by binding the fibers of the fibrous webs A and B to each other, a fiber binding means is selected according to the application and purpose, and the fiber webs A and B having a density of 0.
From the apparent density of 005g / cm ^3, a dense one has a apparent density of about 0.9 g / cm ^3.

The nonwoven fabrics A and B of the present invention have excellent texture. That is, the absolute value of the main correlation coefficient of the texture calculated from the brightness information of the reflected light when irradiating light on at least one surface is equal to or less than the value α obtained from the following equation, the texture is uniform. Nonwoven fabrics A and B. α = 4.6692 × W ^−0.7222 (where W is the basis weight of the nonwoven fabrics A and B (g / m ² )) As described above, the nonwoven fabrics A and B of the present invention are excellent in texture and thus have a basis weight of It can also have a very low basis weight of 1 g / m ² . The basis weights of the nonwoven fabrics A and B of the present invention are
It can be about 1 to 100 g / m ² .

This is an important characteristic of the nonwoven fabrics A and B of the present invention.
The main correlation coefficient of formation is described below. The present invention
"Main correlation coefficient of texture" in Japanese Patent Laid-Open No. 2001-2001
According to the method disclosed in documents such as 50902 publication.
Is the value measured by (1) the object to be measured (nonwoven fabric A,
B, the same shall apply hereinafter), irradiating light to a predetermined area
The reflected light is received to obtain the brightness information (2)
Divide the prescribed area of the regular object into a prescribed image size
(3) Calculate the brightness value of each divided section,
Calculate the main coefficient of variation corresponding to the image size (4)
Main changes of (2) to (3) by changing the size of the fixed image size
Repeating the calculation of the coefficient of motion (5) with a plurality of image sizes
Shows the correlation with the corresponding main coefficient of variation
It is measured by the method of calculating the main correlation coefficient. The present invention
The specific measurement method in the case of is as follows. (1) For an arbitrary 75 mm square area of the measured object,
Scan using a page scanner with 400 dpi resolution
The brightness information of the reflected light in each pixel is set to 0 to 25
Obtained with a gradation of 5. (2) Measured area of 75 mm square is 1.5 mm pitch
2500 with 1.5mm square image size divided into a grid
Luminance value obtained by averaging the luminance of the pixels in each parcel
And the brightness value group G with an image size of 1.5 mm square_1.5= (G
_1.5-1, G_1.5-2, ... g_1.5-2500) Get. (3) Luminance value group G_1.5The standard deviation of
Coefficient of motion CV_1.5To get (4) Similarly, 3.0 mm square, 6.0 mm square, 12.0
Luminance value group G of mm-square image size_Three, G₆, G₁₂Got
Then, for each luminance value group, the main coefficient of variation CV_Three, CV ₆, C
V₁₂To calculate. (5) Plot the following four coordinates (X, Y) on the XY plane.
To (1, CV_1.5), (2, CV_Three), (3, C
V₆), (4, CV₁₂) Regressing these four points into a linear line by the method of least squares
Thus, the slope is obtained as the main correlation coefficient of formation.
Generally, the larger the X-coordinate image size, the more the main fluctuation.
As the coefficient decreases, the linear line drops to the right,
The main correlation coefficient is a negative value. Work of these series of calculations
Use a PC to run statistical software, spreadsheet software, etc.
If applied, it can be easily performed.

The main correlation coefficient of the texture obtained in this manner indicates the correlation between the expansion of the image size and the coefficient of variation of the brightness value. The smaller the absolute value of the main correlation coefficient of the texture is, the smaller the correlation coefficient is. It is an index showing that the texture of the nonwoven fabrics A and B is excellent. The main correlation coefficient of this formation is
It is excellent as a means for objectively evaluating the uniformity and roughness of the texture, but even if non-woven fabrics A and B having the same apparent density are produced by the same production method using the same fiber, the basis weight varies. There is a characteristic that the main correlation coefficient of formation changes. That is, a correction is required to compare those having different basis weights. Therefore, in order to correct the variation due to the basis weight,
The following formula is used. α = 4.6692 x W ^-0.7222 (W is the weight of nonwoven fabrics A and B (g / m ² ))

The nonwoven fabrics A and B of the present invention are ultrafine fibers A and B.
Various characteristics due to inclusion of (for example, filtration performance,
Since the nonwoven fabrics A and B of the present invention are excellent in flexibility, wiping property, and / or concealing property, etc., they are, for example, gas or liquid filters (hepa filters, bag filters, cartridge filters, etc.), deodorizing filter bases. Materials, base materials for deodorant filters, base materials for masks (surgical, industrial, etc.), filter presses, surgical drapes, surgical gowns, diaper cover rings, battery separators, water absorbent sheets (for humidifiers, etc.), etc. It can be used for various purposes.

The sheet material of the present invention is the above-mentioned 4 non-woven fabric A.
Alternatively, at least one layer of the non-woven fabric B is contained. That is, the sheet material of the present invention includes one or more layers of the above-mentioned non-woven fabric A or non-woven fabric B and one or more layers having different structures (hereinafter referred to as auxiliary layers). As the auxiliary layer, a usual yarn layer, net layer, woven layer, knitted layer,
A fibrous web layer, a film layer, a usual nonwoven fabric layer, etc. can be mentioned. The sheet material including the layer of the non-woven fabric A or the non-woven fabric B and the auxiliary layer is, for example, a fiber web A obtained by accumulating the ultrafine fibers A or the ultrafine fibers B on the auxiliary layer.
Alternatively, it can be produced by forming the fibrous web B and then combining it with the auxiliary layer, or by forming the auxiliary layer and the non-woven fabric A or the non-woven fabric B and then combining them by an appropriate connecting means.

Since the sheet material according to the present invention contains at least one layer of the above-mentioned nonwoven fabric A or nonwoven fabric B,
It is excellent in various characteristics (for example, filtration performance, flexibility, wiping property, and / or concealing property) by including the layer of the ultrafine fibers A or the ultrafine fibers B, and is provided with an auxiliary layer made of various materials. As a result, the characteristics of the auxiliary layer are imparted. For example, if the strength of the auxiliary layer is high, the strength of the layer of the nonwoven fabric A or the nonwoven fabric B can be supplemented.
Such a sheet material can be applied to various uses. For example, gas or liquid filter (hepa filter, bag filter, cartridge filter, etc.), deodorizing filter substrate, deodorizing filter substrate, mask substrate (surgical, industrial etc.), filter press, surgical drape, It can be suitably used for various applications such as surgical gowns, diaper coverings, battery separators, and water absorbing sheets (for humidifiers).

The nonwoven fabric B of the present invention can be manufactured, for example, by the following method. First, the fiber diameter is 4 μm or less, the fiber length is 3 mm or less, and the adherence rate of adhered matter is 0.5 m.
ass% or less (preferably 0.3 mass% or less, more preferably 0.1 mass% or less, even more preferably 0.08 mass% or less, still more preferably 0.06
mass% or less, even more preferably 0.04 mass
% Or less, and even more preferably 0.02 mass% or less)
An aggregate of ultrafine fibers B (in particular, a bundle-like aggregate) or an aggregate group thereof (in particular, an aggregate group including a plurality of bundle-like aggregates in a bundle) and / or mechanical division Then, the fiber diameter is 4 μm or less, the fiber length is 3 mm or less, and the adherence rate of adhered matter is 0.5 mass% or less (preferably 0.3 mass%).
% Or less, more preferably 0.1 mass% or less, even more preferably 0.08 mass% or less, even more preferably 0.06 mass% or less, still more preferably 0.
04 mass% or less, and even more preferably 0.02 ma
splittable fibers B capable of generating ultrafine fibers B (ss% or less),
Alternatively, those aggregates (particularly, bundle-like aggregates) are prepared. Two or more kinds of ultrafine fibers B may be used in combination.

The ultrafine fiber B aggregate having a low adherence rate of the adhered matter or a group of aggregates thereof and / or the ultrafine fiber-producible fiber B having a low adherence rate of the adherent or the aggregate thereof is, for example, Fiber diameter is 4 μm or less and fiber length is 3 m
After preparing commercially available ultrafine fiber aggregates of m or less or aggregates thereof, and / or fibers capable of generating ultrafine fibers or aggregates thereof, attachment of deposits with a solvent such as acetone, ethanol or methanol Rate is 0.5 ma
It can be obtained by washing until it becomes ss% or less. In addition, by extracting and removing sea components from the sea-island fiber,
It is possible to obtain an aggregate of ultrafine fibers B having a low adherence rate of adhered matter. In addition, even the aggregate of the ultrafine fibers B obtained by extracting and removing the sea component from the sea-island type fiber is preferably washed with a solvent such as acetone to further reduce the amount of deposits. As described above, in the aggregate of the ultrafine fibers B having a low adherence rate of the adhered substances such as the surfactant and the sizing agent, static electricity is generated due to friction with the nozzle described later, and the ultrafine fibers B repel each other, so that they are uniformly dispersed. Easy to disperse.

When the ultrafine fibers B aggregate or the ultrafine fibers B in the aggregate group are entangled with each other, the ultrafine fibers B are uniformly dispersed by the action of the compressed gas as described later. Since it tends to be difficult and it is necessary to act the compressed gas many times, it is preferable that the ultrafine fibers B or the ultrafine fibers B in the aggregate group are not in a entangled state. For example, an ultrafine fiber aggregate obtained by beating mechanically dividable splittable fibers with a beater, a pulp beaten with a beater, or an ultrafine fiber aggregate obtained by a flash spinning method,
It is preferable not to use it because the ultrafine fibers are entangled with each other. It should be noted that splittable fibers B that can be mechanically split by the action of compressed gas to generate ultrafine fibers B or an aggregate thereof (for example, wholly aromatic polyamide fiber B or an aggregate thereof, solvent-spun cellulose fiber). B or their aggregates) can be used. When the thick fiber B is contained, the thick fiber B does not need to have a low adherence rate of the adhered matter like the ultrafine fiber B, but the thick fiber B does not impair the dispersibility of the ultrafine fiber B. It is preferable to carry out washing with acetone in advance so that the attached rate of the attached matter is the same as that of the ultrafine fiber B.

Next, the ultrafine fiber B aggregate as described above or an aggregate group thereof, and / or the ultrafine fiber-producible splittable fiber B or an aggregate thereof (as the case may be, a thick fiber B or an aggregate thereof). Or powder) is supplied to the nozzle. In addition, two or more kinds of ultrafine fiber B aggregates or an aggregate group thereof, and / or ultrafine fiber-producible splittable fibers B or aggregates thereof (in some cases,
Furthermore, when the thick fibers B or their aggregates or powders are used in combination, they may be supplied to the nozzle while continuously or discontinuously changing the respective compounding amounts.
By applying a compressed gas to the ultrafine fiber B aggregate or the like, it is ejected from the nozzle into the gas to produce the ultrafine fiber B.
Dividing into ultrafine fibers B from an aggregate or a group of those aggregates, dispersing these ultrafine fibers B, and / or generating ultrafine fibers B from the ultrafine fiber-producible splittable fibers B or their aggregates, The ultrafine fibers B are dispersed. When the thick fibers B or their aggregates or powders are included, the thick fibers B or powders are also dispersed.

This nozzle may have a constant cross-sectional area from the supply side to the ejection side of the ultrafine fiber B aggregate or the like, or the cross-sectional area may be reduced continuously or discontinuously. The cross-sectional area may increase continuously or discontinuously,
The cross-sectional area may increase continuously and discontinuously and then decrease, or may increase continuously and discontinuously and then increase. The cross-sectional area may increase continuously or discontinuously and then decrease. Among these, a nozzle having a continuously increased cross-sectional area is preferable because the fibers are not clogged and the fibers can be uniformly dispersed. An example of such a nozzle is a Venturi tube. The compressed gas supplied to the nozzle preferably has a substantially laminar flow. As the compressed gas, any gas may be used, but it is preferable to use air for manufacturing. Further, the compressed gas is divided into ultrafine fibers B from the ultrafine fiber B aggregate or the aggregate group thereof, and the ultrafine fibers B are dispersed, and / or the ultrafine fiber-producible splittable fibers B or the aggregate thereof. In order to generate ultrafine fibers B from the body and sufficiently disperse those ultrafine fibers B,
Gas passage speed at the nozzle jet is 100 m / se
c. The above is preferable. For the same reason, the pressure of the compressed gas is preferably ² kg / cm ² or more. The “gas passage speed” is a value obtained by dividing the flow rate (m ³ / sec) of the gas ejected from the nozzle at 1 atmospheric pressure by the cross-sectional area (m ² ) at the nozzle ejection port.

In front of the nozzle outlet, the ultrafine fibers B are
An aggregate or an aggregate group thereof, and / or an extremely fine fiber-generating splittable fiber B or an aggregate thereof (in some cases, a thick fiber B or an aggregate or powder thereof) is collided with each other to obtain an individual ultrafine fiber. Collisions having protrusions for promoting generation of fibers B (thick fibers B and / or powders in some cases) and dispersion of generated ultrafine fibers B (thick fibers B and / or powders in some cases) Provide a member. Examples of the collision member include a bell-shaped collision member, a cone-shaped collision member, a collision member in which a bell-shaped projection portion and a flat plate-shaped collision portion are integrated, and a cone-shaped projection portion and a flat plate-shaped collision portion. It is possible to use a collision member in which and are integrated. Among these, a collision member in which a bell-shaped protrusion and a flat plate-shaped collision portion are integrated, or a collision member in which a cone-shaped protrusion and a flat plate-shaped collision portion are integrated is caused by a collision with the projection. Collision between the opening and the colliding part when the colliding part reaches the flat plate-like colliding part along the surface of the projecting part, changes the moving direction of the opening and the ultrafine fibers B, and promotes dispersion of the ultrafine fibers B. It is preferable because it can be performed. Such a collision member may be arranged in front of the nozzle ejection port so that it can collide with the ejected ultrafine fibers B. However, since the ultrafine fibers B are excellent in openability and dispersibility, The flat portion of the collision member (for example, in the case of a collision member having a protrusion and a collision portion, the nozzle ejection port side surface of the collision portion, the conical bottom surface in the case of a conical collision member, a bell-shaped collision member In this case, the shortest distance between the bottom of the bell and the nozzle jet is preferably 1 to 100 mm, more preferably 5 to 40 mm, even more preferably 5 to 30 mm, and 10 to 30 mm.
mm is more preferable, and 10 to 20 mm is most preferable. Also, the collision member is a bell-shaped collision member,
In the case of a conical collision member, a collision member in which a bell-shaped projection portion and a flat plate-shaped collision portion are integrated, or a collision member in which a conical projection portion and a flat-plate-shaped collision portion are integrated, In order that the ultrafine fibers B are excellent in openability and dispersibility, it is preferable to arrange them in a bell shape, a conical shape, or so that the axis of the protrusion is aligned with the center of the nozzle ejection port. In addition, when these collision members are installed, they are installed in a bell shape, a conical shape, or the apex of the protrusion faces the nozzle ejection port so that the ultrafine fibers B have excellent openability and dispersibility. Preferably. The shape of the flat part of the collision member (for example, the nozzle ejection port side surface if it has a flat plate-shaped collision part, the bottom of the cone in the case of a conical collision member, the bottom of the bell in the case of a bell-shaped collision member) The area needs only to be able to sufficiently receive the compressed gas ejected from the nozzle ejection port in the projected area viewed from the nozzle side, and the diameter of the nozzle ejection port, the spread angle of the nozzle, the nozzle ejection port to the collision member. It is appropriately designed depending on the distance, the cross-sectional area of any part of the dispersion chamber, and the like.

The distance from the nozzle ejection port to the end of the dispersion chamber on the side of the collecting member is preferably 3 cm or more and 10 cm or less for the purpose of preventing electrostatic attachment of the ultrafine fibers B to the inner wall of the dispersion chamber. If this distance is less than 3 cm, the dispersibility of the ultrafine fibers B tends to be impaired due to the influence of turbulent flow around the collision member, and it is more preferably 4 cm or more. On the other hand, if this distance exceeds 10 cm, the flow of gas is disturbed or the flow velocity is slowed down, so that the charged ultrafine fibers B tend to adhere to the inner wall of the dispersion chamber and accumulate,
When the amount of deposition exceeds a certain amount, it falls off and the fiber web B
Since it may impair the texture of the above, it is more preferably 9 cm or less. This distance refers to the distance from the center of the nozzle ejection port to a line that passes through the center of the cross section of an arbitrary portion of the dispersion chamber to the end of the dispersion chamber on the side of the collecting member. If the path is bent or curved, the ultrafine fibers B are likely to adhere to the inner wall of the dispersion chamber. Therefore, the path is preferably straight.

Next, the dispersed ultrafine fibers B (including thick fibers B and powders as the case may be) are accumulated on an accumulation member to form a fiber web B. The ultrafine fibers B can be collected by using a support such as a porous roll or a net for the stacking member. The ultrafine fibers B may be naturally dropped and accumulated, or gas may be sucked and accumulated from below the support. In the latter case, the fiber web B can be stably formed by suction, and
It is preferable because it has an effect of improving texture. That is, when suction is performed, the portion of the support on which the ultrafine fibers B are less accumulated has a lower pressure loss than the portion on which the ultrafine fibers B are accumulated, so that the suction force is relatively high. A phenomenon in which a large amount of the ultrafine fibers B accumulate will occur, and the accumulation amount of the ultrafine fibers B will be averaged to improve the texture. The larger the suction force is, the higher this effect is, and the suction air volume of the collecting member is 1.1 times or more, preferably 1.2 times or more, and more preferably 1.3 times or more, with respect to the air volume of the compressed gas jetted from the nozzle. There is no upper limit, but 3 times or less is economical.

When the dispersed ultrafine fibers B (including the thick fibers B or powder depending on the case) are accumulated, the relative position of the accumulating member and the nozzle is moved to obtain a fiber web B having a better texture. Can be manufactured. As this movement, for example, the nozzle is reciprocated in the production direction of the fiber web B and / or in the direction orthogonal to the production direction of the fiber web B, moved circularly or elliptically, or the collecting member is produced in the production direction of the fiber web B. And / or a method of reciprocating in a direction orthogonal to the production direction of the fiber web B can be applied.

Then, the fibrous web B can be bonded to produce a nonwoven fabric B. The bonding method is not particularly limited, but is generally a method used in dry nonwoven fabrics, for example, a method of fusing a fiber web B constituent material (ultrafine fiber B, thick fiber B, or powder), emulsion or latex. A method of bonding with a binder such as, a method of entanglement with a fluid flow such as a needle punch or a water flow,
There is a method of using these alone or in combination. Among these, the method of fusing the fiber web B constituent material,
It is preferable because the ultrafine fibers B can be bonded in a state where they are not in close contact with each other.

The above is the basic method for producing the non-woven fabric B of the present invention, in which the aggregate of the ultrafine fibers B or a group thereof and / or the aggregate of the ultrafine fiber-producible divided fibers B is nozzled. It is possible to mix and pre-open the fibers by using a mixer or the like before supplying to. Furthermore, the non-woven fabric B according to the present invention may be post-processed to suit various applications. For example, the non-woven fabric B can be subjected to a charging treatment, a water repellent treatment, a hydrophilic treatment and the like. The method for producing the nonwoven fabric A according to the present invention includes, as the fibers to be supplied to the nozzle, an aggregate of ultrafine fibers B or an aggregate group thereof, and / or a splittable fiber B capable of generating the ultrafine fibers B, or an aggregate thereof. The present invention is not limited to the use of a body, an aggregate of thick fibers B or a group of aggregates thereof, and a powder, and the resulting non-woven fabric A has an attachment rate of 0.5 mass% or less (preferably 0. 3 mass% or less, more preferably 0.1 mass% or less, even more preferably 0.08 mass% or less, even more preferably 0.06 mass% or less, even more preferably 0.04.
mass% or less, and even more preferably 0.02 mass
% Or less), an aggregate of ultrafine fibers A or an aggregate group thereof, and / or a splittable fiber A capable of generating the ultrafine fibers A, or an aggregate thereof, an aggregate of thick fibers A, or The point that the aggregate group and the powder are used is different from the above-mentioned manufacturing method of the nonwoven fabric B. For example, even in the case of a combination of an aggregate of ultrafine fibers A having an adherence rate of deposits of more than 0.5 mass% and an aggregate of thick fibers A having an deposit rate of 0.5 mass% or less, the present invention The non-woven fabric A (non-woven fabric having an attachment rate of 0.5 mass% or less) can be manufactured. However, from the viewpoint of the dispersibility of the ultrafine fibers A, it is preferable that the attachment rate of the deposits on the ultrafine fibers A is 0.5 mass% or less (= the ultrafine fibers B).

The sheet material containing at least one layer of the nonwoven fabric B of the present invention can be produced, for example, by the following method. An ultrafine fiber B aggregate prepared in the same manner as the nonwoven fabric B or an aggregate group thereof, and / or an ultrafine fiber-producible splittable fiber B or an aggregate thereof (as the case may be, or an aggregate or powder thereof) ) Is supplied to the nozzle in the same manner as in the method for producing the non-woven fabric B, and a compressed gas is applied to them to eject the compressed gas into the gas and collide with a collision member having a projection to obtain an ultrafine particle. The fiber B aggregate or a group of these aggregates is divided into ultrafine fibers B, and / or the splittable fiber B is divided to generate and disperse the ultrafine fibers B. Next, the ultrafine fibers B dispersed on the material (for example, yarn, net, woven fabric, knitted fabric, fiber web, non-woven fabric, film, etc.) to be the auxiliary layer in the same manner as in the method for producing the non-woven fabric B.
(In some cases, thick fiber B or powder) is accumulated,
After the laminated body is formed, the fiber web in which the ultrafine fibers B are accumulated is bonded together with the fiber web and the auxiliary layer. By forming a laminate in this way, the properties of the auxiliary layer can be added to the nonwoven fabric B, and the strength, shape retention, dimensional stability, etc. can be improved. Therefore, the sheet material of the present invention can be applied to various uses. The method of bonding the laminate is not particularly limited, but, for example, when each fiber B constituting the laminate is a thermoplastic fiber, a fiber web B of dispersed ultrafine fibers B is obtained by using a heating device. A method of fusing the fibers of the reinforcing material can be used, and the ultrafine fibers B can be bonded in a state where they are not in close contact with each other. Further, a method of adhering with a binder such as emulsion or latex, a method of entanglement with a fluid flow such as water flow, etc. may be used alone or in combination. Even after forming the non-woven fabric B, the non-woven fabric B may be laminated with a material serving as an auxiliary layer and bonded to produce a sheet material containing at least one layer of the non-woven fabric B. The other sheet material containing at least one layer of non-woven fabric A can also be manufactured in exactly the same manner as the sheet material containing at least one layer of non-woven fabric B.

Next, a manufacturing apparatus that can be used for manufacturing the nonwoven fabrics A and B of the present invention will be described with reference to FIG. The case of using an assembly of ultrafine fibers B having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less (particularly a bundle-shaped assembly) will be described. FIG. 1 is a schematic explanatory view of one embodiment of the apparatus for producing a nonwoven fabric B according to the present invention.

As shown in FIG. 1, the apparatus for producing the nonwoven fabric B of the present invention comprises a mixing device 10, a supply pipe 11, a compressed gas inlet 20, a nozzle 30, a dispersion chamber 40, a collision member 45, a stacking member 50, It has a gas suction device 60, a heat fusion device 90, and a winding device 100.

The mixing device 10 may be, for example, a mixer. With this mixing device 10, ultrafine fibers having a fiber diameter of 4 μm or less, a fiber length of 3 mm or less, and an amount of deposits of 0.5 mass% or less. The B-shaped aggregates, and optionally the thick fibers B or aggregates thereof, or powders can be divided, broken or mixed into smaller aggregates.

The supply pipe 11 is composed of the ultrafine fibers B unmixed or mixed in the mixing device 10 and / or the bundle-like ultrafine fiber B aggregate (in some cases, thick fiber B, its aggregate,
And / or powder) to the nozzle 30. A compressed gas introduction port 20 is provided above the nozzle 30 so that the compressed gas generated by a compressed gas generator (not shown) can be introduced. As the compressed gas, any gas may be used, but it is preferable to use air for manufacturing.
For example, a compressor can be used as the compressed gas generation device. In addition, it is preferable that the compressed gas introduction port 20 can be supplied so that the compressed gas flow from the compressed gas introduction port 20 is a substantially laminar flow.

As the nozzle 30, the above-mentioned loosened or mixed ultrafine fibers B and / or aggregated ultrafine fiber B aggregates (in some cases, thick fibers B, aggregates thereof and / or powder) are also used. The one that can be ejected from the nozzle ejection port by the action of the compressed gas is used. If this nozzle has a cross-sectional area that continuously increases from the compressed gas supply side toward the nozzle ejection port, the fibers B and the like are not clogged, and it is possible to contribute to the uniform dispersion of the fibers B and the like. Is. An example of such a nozzle is a Venturi tube.

A collision member 45 having a projection is provided in front of the ejection port of the nozzle 30, and a bundle-shaped ultrafine fiber B aggregate (in some cases, a thick fiber B and an aggregate thereof) ejected from the nozzle 30. , Or powder) can collide with the collision member 45. The dispersion chamber 40 is attached to the ejection port side of the nozzle 30 so as to surround the collision member 45 and extends to a collecting member 50 described later. The bundle-shaped ultrafine fiber B aggregate (in some cases, the thick fiber B, an aggregate thereof, or powder) is ejected into the gas 40a in the dispersion chamber and collides with the collision member 45 having a projection to form the ultrafine fiber. A and B (70) (in some cases, thick fiber B or powder) are generated and dispersed in the dispersion chamber 40. In FIG. 1, as the collision member 45, one having a conical projection and a flat collision part is used. In the case of the collision member 45, the conical protrusions diffuse the airflow from the nozzle ejection port in multiple directions and collide with the surrounding flat plate-shaped collision portion, so that the fiber B and the like have excellent openability and dispersibility. Therefore, the fiber web B having an excellent texture can be obtained. However, the collision member of the present invention is not limited to such a collision member, and for example, a bell-shaped collision member, a cone-shaped collision member, a collision in which a bell-shaped projection portion and a flat plate-shaped collision portion are integrated. A member or the like can be used.

Since the collecting member 50 is provided at the bottom of the dispersion chamber 40, the ultrafine fibers B dispersed in the gas 40a in the dispersion chamber 40 and descending in the dispersion chamber 40 (thick fibers B and / or Alternatively, the fibrous web B (80) can be formed by accumulating 70 (including powder) on the accumulating member 50. Collection member 5
0 using a porous roll, net, etc.
When the gas suction device 60 is provided below 0, the gas 40a in the dispersion chamber 40 is sucked, the formation of the fiber web B is stabilized, and the texture is improved. As the gas suction device 60, for example, a suction box or the like can be used.

If the relative position of the collecting member 50 or the nozzle 30 can be moved, the fibrous web B having a better texture can be manufactured. As this movement, for example, the nozzle is reciprocated in the production direction of the fiber web B and / or in the direction orthogonal to the production direction of the fiber web B,
Move in a circle or an ellipse, or use the fiber web B
A method of reciprocating in a direction orthogonal to the production direction of and / or the production direction of the fiber web B can be applied.

The collecting member 50 is movable, and the basis weight of the fibrous web B can be adjusted by adjusting the moving speed. The fibrous web B (80) is conveyed to the heat fusion device 90 by the movement of the stacking member 50. The heat-sealing device 90 can be composed of, for example, a hot air dryer or the like. By using this heat fusion device 90, the fiber web B
The non-woven fabric B (83) can be formed by heating (80) to fuse the ultrafine fibers B and the like. Nonwoven fabric B (8
3) can be wound by the winding device 100.

[0065]

The present invention will be described in detail below with reference to examples, but these do not limit the scope of the present invention. (Example 1) A sea-island type fiber obtained by the composite spinning method in which 25 island components composed of high-density polyethylene and polypropylene are present in the sea component composed of polylactic acid (fineness: 1.
7 dtex, which was cut to a length of 1 mm) was prepared. This sea-island type fiber is dipped in a 10 mass% sodium hydroxide aqueous solution to extract and remove polylactic acid which is a sea component by hydrolysis, and then air-dried to obtain an ultrafine fiber B1 (fiber which is a mixture of high density polyethylene and polypropylene). Diameter:
2 μm, fiber length: 1 mm, unfibrillated, stretched, having substantially the same diameter in the fiber axis direction, adhesion rate of deposits: less than 0.02 mass%, cross-sectional shape: sea-island type) I got an assembly. Then, an ultrafine fiber web was manufactured by a fiber web manufacturing apparatus as shown in FIG. That is, the bundle of ultrafine fibers B1 is supplied to the mixer (10) to be unraveled, and compressed from the compressor into a venturi tube (30) having a circular cross-sectional shape (diameter: 8.5 mm) at the nozzle ejection port. Gas inlet 20
By introducing compressed air (pressure = 6 kg / cm ² , substantially laminar flow) through the above, the unraveled bundle-like aggregate is supplied from the material supply port 11 to the Venturi tube (30), and the Venturi tube is used to supply the ultrafine fibers. B1 bundle-like aggregates are jetted into the air (gas passage speed at the jet port of the Venturi tube (30): 147 m / s, jet amount from the jet port: about 0.5)
m ³ / min. ) Then, the microfiber B1 is collided with a collision member 45 provided in front of the ejection port of the Venturi tube and provided with a conical protrusion and a flat plate-shaped collision portion (transverse sectional shape: circular, diameter: 25 mm). Dispersed. The collision member 45
Is 15 mm from the nozzle outlet to the flat plate impact part
Moreover, the apex of the protrusion is arranged so as to face the nozzle ejection port so that the axis of the protrusion coincides with the center of the nozzle ejection port. Then, the dispersed ultrafine fibers B1
Is supplied to the net (collection member 50) by a dispersion chamber 40 that surrounds the collision member 45 and is connected to the Venturi tube (30) and linearly extends in the direction of the net capable of accumulating the ultrafine fibers B1. , A wet non-woven fabric made of polyethylene terephthalate fibers placed on a moving net (weight per unit area: 10 g / m ² , average fiber diameter: 3.2).
μm) to form a microfiber web B1. In addition, at the time of stacking, 0.7 m ³ / min. I sucked in. The distance from the nozzle ejection port to the end of the dispersion chamber 40 on the side of the collecting member was 8 cm, and the air flow rate at the end of the dispersion chamber 40 on the side of the collecting member was 4.6 m / s.

This ultrafine fiber web B1-wet non-woven fabric laminate was placed in an oven (heat fusion apparatus 90) at a temperature of 135 ° C.
After passing through for a minute, the ultrafine fiber web B1 is bonded with the high-density polyethylene component of the ultrafine fiber B1 and then passed through a Reliant press (temperature: 135 ° C., 20 seconds) and allowed to cool, and then the ultrafine fiber web B1-wet nonwoven laminate The wet non-woven fabric substrate was peeled off from the body to prepare an ultrafine non-woven fabric B1 having a basis weight of 10 g / m ² , a thickness of 0.03 mm and an apparent density of 0.3 g / cm ³ . Four

Example 2 By the same method as in Example 1, an ultrafine nonwoven fabric B2 having a basis weight of 40 g / m ² , a thickness of 0.12 mm and an apparent density of 0.3 g / cm ³ was prepared. (Measurement of Adhesion Rate of Adhered Substances) The ultrafine nonwoven fabric B1 and the ultrafine nonwoven fabric B2 obtained in Example 1 and Example 2 were each placed in hot water 1 times.
The amount of deposits soaked and extracted for 5 minutes or the amount of deposits soaked and extracted in warm methanol for 15 minutes was 0.
It was less than 02 mass%.

(Measurement of texture) A 75 mm square area of the ultrafine nonwoven fabric B1 and the ultrafine nonwoven fabric B2 obtained in Example 1 and Example 2 was scanned using a page scanner with a resolution of 400 dpi and reflected at each pixel. Luminance information of light was acquired with gradations of 0 to 255. About this brightness information, image size 1.5 mm square, 3.0 mm square, 6.0 m
Luminance value group G _{1.5 at} m-square, 12.0 mm-square,
G ₃ , G ₆ , and G ₁₂ were calculated, and the main variation coefficient obtained by dividing the standard deviation of the luminance value group by the average value was obtained. Main variation coefficients CV _1.5 , CV ₃ , CV ₆ , and CV ₁₂ are taken on the Y axis,
Four points plotted by setting the X-axis coordinates as 1, 2, 3, and 4 in order were regressed to a linear straight line by the least squares method, and the main correlation coefficient of formation was obtained. The absolute value of the main correlation coefficient of the texture of the ultrafine non-woven fabric B1 and the ultrafine non-woven fabric B2 and the α value were determined by the following formula, and summarized in Table 1. α = 4.6692 x W ^-0.7222 (W is the weight of ultrafine nonwoven fabric B1 and ultrafine nonwoven fabric B2 (g / m ² ))

[Table 1] In all of the basis weights, the absolute value of the main correlation coefficient of texture was much lower than the α value, and it was the ultrafine nonwoven fabric B1 and the ultrafine nonwoven fabric B2 whose texture was extremely uniform visually. (Example 3) An aggregate of ultrafine fibers B1 was obtained in the same manner as in Example 1. Further, there are 25 island components composed of polypropylene in the sea component composed of polylactic acid, and sea-island type fibers obtained by the composite spinning method (fineness: 1.7 dtex, length 1 m).
(cut into m) was prepared. This sea island type fiber 1
After immersing in a 0 mass% sodium hydroxide aqueous solution to extract and remove polylactic acid as a sea component by hydrolysis,
Air-dry and use polypropylene microfiber B3 (fiber diameter: 2μ
m, fiber length: 1 mm, unfibrillated, stretched, having substantially the same diameter in the fiber axis direction, adhesion rate of deposits: less than 0.02 mass%, cross-sectional shape: sea-island type) I got an assembly. Next, ultrafine fiber B
Microfiber fiber web B1, in the same manner as in Example 1 except that the bundle-shaped aggregate of 1 and the ultrafine fibers B3 was supplied to the mixer (10) at a mass ratio of 30:70, and was mixed and dissolved.
A B3-wet nonwoven fabric laminate was prepared. Then, the ultrafine fiber webs B1 and B3-wet non-woven fabric laminated body are heated at a temperature of 14
After heat treatment for 3 minutes with a suction drum dryer set to 0 ° C., the ultrafine fiber webs B1 and B3 are bonded by a high-density polyethylene component and allowed to cool, and then the ultrafine fiber webs B1 and B3-wet nonwoven fabric laminate The non-woven fabric substrate was peeled off to prepare an ultrafine non-woven fabric B3 having a basis weight of 80 g / m ² , a thickness of 2.2 mm (non-load) and an apparent density of 0.036 g / cm ³ . The α value of this ultrafine nonwoven fabric B3 is 0.19
When the absolute value of the main correlation coefficient of texture was measured in the same manner as in Example 1, it was 0.095, which was significantly lower than the α value, and was an extremely fine nonwoven fabric B3 having extremely uniform texture. For reference, the filter performance was measured, and the following results were obtained.

(Measurement of filter performance) The HEPA filter performance of the ultrafine nonwoven fabric B3 obtained in Example 3 (wind speed: 5.
3 cm / s, test particles: DOP (di (2-ethylhexidyl phthalate) phthalate) was examined, and the collection efficiency for 0.3 μm particles was 99.988%, which was 9% of the target value.
While exceeding 9.97%, the pressure loss also showed a low value of 230 Pa, which was well below the target value of 400 Pa, indicating excellent filter performance.

Example 4 Extra fine fibers B1 as in Example 1
Got a collection of. Further, a core-sheath type composite fiber (fiber diameter 1
1.2 μm, fiber length 3 mm, not fibrillated,
Stretched, having substantially the same diameter in the fiber axis direction, manufactured by Chisso Co., Ltd.) in hot water and warm ethanol at a temperature of 80 ° C., and washed and dried until the rate of adhered substances becomes 0.02 mass% or less. Then, thick fiber B1 was obtained. Then
A fiber web B4-wet non-woven fabric laminate was obtained in the same manner as in Example 1 except that the ultrafine fibers B1 and the thick fibers B1 were mixed at a mass ratio of 67:33 by being supplied to a mixer (10) for melting and mixing. Created. This fibrous web B4-wet nonwoven fabric laminate is heat-treated for 3 minutes with a suction drum dryer set at a temperature of 140 ° C. to bond the fibrous web B4 with the high-density polyethylene component of the ultrafine fibers B1 and the polyethylene component of the thick fibers B1. And let it cool down,
Fiber web B4-wet non-woven fabric base material is peeled off from the non-woven fabric laminate to obtain non-woven fabric B4 (Basis weight: 60 g / m ² , thickness:
1.5mm (no load), apparent density: 0.040g / c
m ³ ) was created. The α value of this non-woven fabric B4 is 0.243
When the absolute value of the main correlation coefficient of texture was measured in the same manner as in Example 1, it was 0.177, which was significantly below the α value, and was a very uniform texture nonwoven fabric. (Example 5) An aggregate of ultrafine fibers B1 was obtained in the same manner as in Example 1. Further, a core-sheath type composite fiber having a sheath component of polyethylene and a core component of polypropylene (fiber diameter 21.6 μm,
A fiber length of 3 mm, non-fibrillated, stretched, and having substantially the same diameter in the fiber axis direction, manufactured by Chisso Co., Ltd. was used in warm water and warm ethanol at a temperature of 80 ° C. To 0.02 mass% or less and washed to obtain thick fiber B2. The ultrafine fiber B
A fibrous web B5-wet non-woven fabric laminate was prepared in the same manner as in Example 1 except that 1 and the thick fiber B2 were supplied to the mixer (10) at a mass ratio of 67:33, and were mixed together. This fibrous web B5-wet nonwoven fabric laminate is heat-treated for 3 minutes with a suction drum dryer set at a temperature of 140 ° C., and the fibrous web B5 is bonded with the high-density polyethylene component of the ultrafine fibers B1 and the polyethylene component of the thick fibers B2. After allowing to cool, the wet non-woven fabric base material is peeled off, and the non-woven fabric B5 (weight: 120 g /
m ² , thickness: 2.8 mm (non-loaded), apparent density: 0.04
3 g / cm ³ ) was prepared. The α value of this non-woven fabric B5 was 0.147, and when the absolute value of the main correlation coefficient of the formation was measured in the same manner as in Example 1, it was 0.105, which was considerably lower than the α value, and the formation was extremely uniform. It was a non-woven fabric.

COMPARATIVE EXAMPLE 1 Except that the collision member 45 is not provided in the apparatus for manufacturing the nonwoven fabric B shown in FIG. Tried to make the fibrous web B in the same manner as in Example 1, but a very fast flow velocity drift was generated on the collecting member 50, and the ultrafine fibers B1 on the collecting member 50 were generated.
Was blown away, and the ultrafine fiber web B1 could not be formed. Therefore, with respect to the ejection air amount 0.5 m ³ / min from a nozzle of a compressed gas, suction air quantity three times the 1.5 m ³ / min with a result of attempting raised from the bottom of the integrated member, the dispersion chamber of the lower Although a slight formation of a fibrous web was observed at the outer peripheral portion, the generation of very fast drift below the jet outlet remained unchanged, and a good ultrafine fibrous web B1 could not be formed.

Comparative Example 2 Polyethylene as a sheath component,
A core-sheath type composite fiber having polypropylene as a core component (average fiber diameter: 16 μm, cut fiber length: 51 mm, crimped, stretched, and having substantially the same diameter in the fiber axis direction, a fiber oil agent is about 0 .3 mass% adhesion, using Chisso Co., Ltd. 100%, according to the usual dry nonwoven fabric manufacturing method, after making a card fiber web, fiber bonding treatment in a hot air dryer (temperature: 140 ° C., 3 minutes) After carrying out, it is rolled with a calendar and the basis weight is 80 g / m.
² , the thickness is 0.2 mm, the apparent density is 0.40 g / c
A fused non-woven fabric of m ³ was obtained. The α value of this fused non-woven fabric is 0.
197, and the absolute value of the main correlation coefficient of formation is calculated in Example 1.
When measured in the same manner as above, the value was 0.427, which was considerably higher than the α value, and it was found that the nonwoven fabric had a slightly uneven texture, which was in good agreement with the visually ununiform texture. (Comparative Example 3) Split fibers composed of polyester and nylon (cross section: radial orange, 8 split, average fiber diameter of fine fibers generated by splitting: 5 μm, cut fiber length: 44 mm,
About 0.3 of crimped, stretched, fiber oil
100% of Kanebo Co., Ltd. with mass% adhered is used, and a card fiber web is prepared according to a usual method for producing a dry non-woven fabric, and then hydro-entanglement treatment is performed to divide the divided fibers into fine fibers. The fibers are generated and the fibers are entangled with each other, and the basis weight is 55 g / m ² and the thickness is 0.3.
In mm, an entangled nonwoven fabric having an apparent density of 0.18 g / cm ³ was obtained. The α value of this entangled nonwoven fabric was 0.258, and the absolute value of the main correlation coefficient of the formation was measured in the same manner as in Example 1. As a result, it was 0.435, which was considerably higher than the α value, and the remaining formation was uniform. It was found that it was a non-woven fabric, which was in good agreement with the non-uniformity of the texture visually.

[0073]

Industrial Applicability The ultrafine fiber-dispersed nonwoven fabric of the present invention can be applied to various applications, such as having a proper amount and size of voids and reducing pressure loss. In addition, since ultrafine fibers are not in a bundled state but in a dispersed state, not only are the various characteristics (filterability, flexibility, etc.) due to the inclusion of ultrafine fibers excellent, but also the uniformity of texture. High appearance and good appearance.

The other ultrafine fiber-dispersed nonwoven fabric of the present invention has an extremely small amount of deposits such as a surfactant and a sizing agent on the ultrafine fibers, and the adhesion between the ultrafine fibers is low, so that it can be applied to various applications. Also, ultrafine fibers are not in a bundle,
Since they are in a dispersed state, not only are they excellent in various properties (filterability, flexibility, etc.) due to the inclusion of ultrafine fibers, but they also have a high uniformity of texture and a good appearance.

Since the sheet material of the present invention contains at least one layer of any of the above ultrafine fiber-dispersed nonwoven fabrics,
It is a sheet material that can exhibit the performance of the nonwoven fabric A or the nonwoven fabric B.

The method for producing an ultrafine fiber-dispersed nonwoven fabric according to the present invention has an adhesion rate of 0.5 ma in which ultrafine fibers are dispersed.
An ultrafine fiber-dispersed nonwoven fabric containing ss% or less, that is, an ultrafine fiber-dispersed nonwoven fabric having a low degree of adhesion of ultrafine fibers and good texture can be easily produced.

Another method for producing an ultrafine fiber-dispersed non-woven fabric of the present invention is to prepare an ultrafine fiber-dispersed non-woven fabric in which ultrafine fibers are sufficiently dispersed and have a uniform and good texture, that is, an ultrafine fiber-dispersed non-woven fabric having a low degree of adhesion of ultrafine fibers. Can be manufactured.

The method for producing a sheet material of the present invention is a series of steps for producing an ultrafine fiber-dispersed nonwoven fabric to easily produce a uniform and well-formed sheet material having an ultrafine fiber-dispersed nonwoven fabric layer and an auxiliary layer. You can

The manufacturing apparatus of the present invention can manufacture the ultrafine fiber-dispersed nonwoven fabric or sheet material.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a production apparatus capable of producing an ultrafine fiber-dispersed nonwoven fabric of the present invention.

[Explanation of symbols]

10 Mixing device 11 supply pipe 20 Compressed gas inlet 30 nozzles 40 dispersion chamber 45 Collision member 50 integrated members 60 Gas suction device 70 Extra fine fiber 80 fiber web 83 Ultrafine fiber dispersed non-woven fabric 90 heat fusion device 100 winding device

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4D019 AA01 AA03 BA13 BB03 CB06                       DA01 DA03                 4L031 AB34 BA11 CA01 CA09 DA00                 4L047 AA14 AA21 AA28 AB02 AB07                       AB08 BA21 BA23 BA24 CA02                       CB10 CC12 CC16 DA00 EA22

Claims (11)

[Claims] 1. A microfiber-dispersed non-woven fabric comprising at least one fiber having a diameter of 4 μm or less and a fiber length of 3 mm or less in a dispersed state, and having a deposition rate of deposits of 0.5 mass% or less, at least on one side. An ultrafine fiber-dispersed non-woven fabric, characterized in that the absolute value of the main correlation coefficient of the texture calculated from the brightness information of the reflected light when the surface of is irradiated with light is equal to or less than the value of α obtained from the following equation. α = 4.6692 × W ^−0.7222 (W is the weight of the ultrafine fiber-dispersed nonwoven fabric (g / m ² )) 2. An ultrafine fiber-dispersed non-woven fabric, containing at least fine fibers having a fiber diameter of 4 μm or less, a fiber length of 3 mm or less, and an attachment rate of 0.5 mass% or less in a dispersed state. The absolute value of the main correlation coefficient of the texture calculated from the brightness information of the reflected light when irradiating light on one surface is less than the value of α obtained from the following formula . α = 4.6692 × W ^−0.7222 (W is the weight of the ultrafine fiber-dispersed nonwoven fabric (g / m ² )) 3. An ultrafine fiber-dispersed non-woven fabric, which contains ultrafine fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less in a dispersed state, and has a deposition rate of deposits of 0.5 mass% or less, at least on one side. At least 1 layer of the ultrafine fiber-dispersed nonwoven fabric whose absolute value of the main correlation coefficient of the texture calculated from the brightness information of the reflected light when irradiating the surface of A sheet material containing layers. α = 4.6692 × W ^−0.7222 (W is the weight of the ultrafine fiber-dispersed nonwoven fabric (g / m ² )) 4. A fiber diameter of at least 4 μm and a fiber length of 3 mm or less, and an attachment rate of 0.5 mass%.
Including the following ultrafine fibers dispersed, is an ultrafine fiber dispersed nonwoven fabric, the absolute value of the main correlation coefficient of the texture calculated from the brightness information of the reflected light when irradiated with light on at least one surface A sheet material containing at least one layer of an ultrafine fiber-dispersed nonwoven fabric having a value of α or less obtained from the following formula. α = 4.6692 × W ^−0.7222 (W is the weight of the ultrafine fiber-dispersed nonwoven fabric (g / m ² )) 5. An assembly of ultrafine fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, or a group of such fibers, and / or a mechanically divided fiber diameter of 4 μm.
A splittable fiber capable of generating an ultrafine fiber having a fiber length of 3 mm or less, or an aggregate thereof, is jetted into the gas from the nozzle by the action of the compressed gas, and is provided in front of the nozzle jet port. By colliding with a collision member having a projection, the ultrafine fiber aggregate or the aggregate group thereof is divided into ultrafine fibers, and / or the splittable fiber or the aggregate thereof is divided into ultrafine fibers, and the ultrafine fibers thereof are divided. A method for producing an ultrafine fiber-dispersed non-woven fabric, comprising: a step of dispersing fibers, a step of accumulating the dispersed ultrafine fibers on an accumulating member to form a fiber web, and a step of bonding the fiber webs. 6. A fiber diameter of at least 4 μm and a fiber length of 3 mm or less, and an adherence rate of adherents is 0.5 mass%.
An aggregate of the following ultrafine fibers, or an aggregate group thereof, and / or mechanically divided to have a fiber diameter of 4 μm or less, a fiber length of 3 mm or less, and an attachment rate of 0.5 m.
splittable fiber capable of generating ultrafine fibers having an ass% or less,
Alternatively, the aggregate is ejected into the gas from the nozzle by the action of compressed gas, and collides with a collision member having a projection, which is provided in front of the nozzle ejection port, and the ultrafine fiber aggregate or an aggregate thereof. Dividing the body group into ultrafine fibers, and / or dividing the splittable fiber or an aggregate thereof into ultrafine fibers, and dispersing the ultrafine fibers, and collecting the dispersed ultrafine fibers on a collecting member. A method for producing an ultrafine fiber-dispersed nonwoven fabric, comprising the steps of forming a fiber web and bonding the fiber web. 7. In the step of forming the fiber web by accumulating the dispersed ultrafine fibers on an accumulating member, the fibrous web is formed by sucking compressed air with an air volume 1.1 times or more the air volume ejected from the nozzle. The method for producing an ultrafine fiber-dispersed nonwoven fabric according to claim 5 or 6, characterized in that 8. A relative position between a nozzle and a stacking member is moved in the step of stacking the dispersed ultrafine fibers on a stacking member to form a fiber web. 8. The method for producing an ultrafine fiber-dispersed nonwoven fabric according to any of 7. 9. An assembly of ultrafine fibers having a fiber diameter of 4 μm or less and a fiber length of 3 mm or less, or a group thereof, and / or a mechanically divided fiber diameter of 4 μm or less and a fiber length of 3 mm. The following splittable fibers capable of generating ultrafine fibers, or an aggregate thereof, are jetted into the gas from the nozzle by the action of the compressed gas, and are provided in front of the nozzle jet port to a collision member having a protrusion. A step of colliding, dividing the ultrafine fiber aggregate or the aggregate group thereof into ultrafine fibers, and / or dividing the splittable fiber or the aggregate thereof into ultrafine fibers, and dispersing the ultrafine fibers, A step of collecting dispersed ultrafine fibers on an auxiliary layer to form a fibrous web; bonding the fibrous web and bonding it to the auxiliary layer. Manufacturing method of grate material. 10. A fiber diameter of at least 4 μm, a fiber length of 3 mm or less, and a deposition rate of deposits of 0.5 mass%.
An aggregate of the following ultrafine fibers, or an aggregate group thereof, and / or mechanically divided to have a fiber diameter of 4 μm or less, a fiber length of 3 mm or less, and an attachment rate of 0.5 m.
splittable fiber capable of generating ultrafine fibers having an ass% or less,
Alternatively, the aggregate is ejected into the gas from the nozzle by the action of compressed gas, and collides with a collision member having a projection, which is provided in front of the nozzle ejection port, and the ultrafine fiber aggregate or an aggregate thereof. Dividing the body group into ultrafine fibers, and / or dividing the splittable fiber or an aggregate thereof into ultrafine fibers, and dispersing the ultrafine fibers, collecting the dispersed ultrafine fibers on an auxiliary layer A method for producing a sheet material, comprising the steps of forming a fibrous web and bonding the fibrous web with an auxiliary layer. 11. (1) An assembly of ultrafine fibers having a fiber diameter of at least 4 μm and a fiber length of 3 mm or less, or a group of these fibers, and / or a mechanically divided fiber diameter of 4
A nozzle capable of ejecting splittable fibers capable of generating ultrafine fibers having a fiber length of 3 μm or less at μm or less, or an aggregate thereof into a gas by the action of a compressed gas,
(2) means for supplying compressed gas to the nozzle, (3) collision member having a projection provided in front of the nozzle ejection port, (4) aggregate of the ultrafine fibers or aggregate group thereof, and / Or, a dispersion chamber for dispersing the ultrafine fibers capable of generating splittable fibers or an aggregate thereof by the action of the compressed gas into the gas by the action of the compressed gas, and dispersing the ultrafine fibers generated by collision with the collision member in the gas, ( 5) An ultrafine fiber-dispersed non-woven fabric, comprising: an accumulating member for accumulating ultrafine fibers dispersed in the gas in the dispersion chamber, and (6) means for binding the web accumulated on the accumulating member. Manufacturing equipment.