CN1810167B - Dry-laid cigarette filter rod and preparation method thereof - Google Patents

Abstract

The invention discloses a dry-process paper cigarette filter rod and a preparation method thereof. The base material of the filter element adopts wood pulp fiber and 5% to 65% heat-melting sheath-core fiber. First use non-toxic esters or ethers for antistatic treatment of the sheath-core fiber, so that the specific resistance is less than 9×10 ⁸ (Ω·cm). Then the opened wood pulp fiber and sheath-core fiber are metered and conveyed, air-laid, and pressure-free heated and formed under negative pressure. After spraying the glue, through the ladder-shaped temperature difference drying tunnel, drying, curing and puffing are completed at one time, and after being shaped by cold air, a dry method with a weight of 35g/m ² to 75g/m ² and a thickness of 0.8mm to 3.5mm is formed. Paper. Finally, the cigarette filter tip made by filter rod molding has a filtration rate of more than 43% and a hardness of more than 89%, which fully meets the relevant national standards for filter rods. After repeated pinching and squeezing, and being affected by the smoke moisture absorbed during the filtering process, the filter still has an ideal rebound effect.

Description

Dry-laid cigarette filter rod and preparation method thereof

Technical field

The invention relates to a cigarette filter rod and a preparation method thereof, in particular to a dry-laid paper cigarette filter rod and a preparation method thereof.

Background technique

With the improvement of people's quality of life and the increasing awareness of health, the problem of cigarette tar reduction has not only received full attention from the cigarette industry, but also attracted the attention of the World Health Organization and governments of various countries. Inserting filter tips on cigarettes has low cost and intuitive effect, and is an effective measure for cigarettes to filter tar and nicotine. More than 98% of cigarettes in the world are equipped with filter tips. Currently, the filter materials used in cigarettes sold on the market are mainly divided into two categories: one is acetate fiber, and the other is polypropylene fiber. Adopt the filter tip that polypropylene fiber is made, although price is lower, there are following problems, as: lack of elasticity, and filtration rate is lower, and general length is the filter tip of 2cm, and filtration rate is only about 32%; Poor, with a certain spicy taste, usually only for low-grade cigarettes. The filter tip made of cellulose acetate has a higher filtration rate, and a filter tip of the same length can increase the filtration rate to about 40%, and the taste is good, but the price is correspondingly higher. In addition, due to the limited domestic production capacity, a considerable part of the materials are still dependent on imports. Currently, they are generally used for medium and high-end cigarettes, accounting for about 80% of the total market. However, both acetate and polypropylene filters are extremely difficult to degrade after being discarded. In order to solve these problems, in recent years, people in the industry are looking for a filter material with high filtration rate, good taste, environmental protection and low cost. Because wood pulp fibers have a strong adsorption force, some people use crepe paper to make filters. CN1048492A discloses a "paper filter stick", which uses high-grade pulp as a special paper with dense corrugations pressed out as a raw material to make a paper filter stick for cigarettes. However, due to the congenital deficiency of raw materials, the filter sticks after making are soft and easily cause shrinkage, so it is difficult to meet the national standards for filter sticks. And because the corrugated density distribution of corrugated paper is uneven, if the filling amount is small, the filter rod will be soft, and if the filling amount is too large, it will cause large suction resistance, especially the smell of filtered smoke is not as good as acetate fiber. Another example is the Chinese invention patent "Natural Fiber Filter Rod" (ZL01255200), which uses natural fibers and additives to make filter rods by foaming in the mold cavity through heating and pressure. In view of the fact that this invention needs to be equipped with unique processing equipment, and it is difficult to control the air permeability and filtration rate, it is difficult to enter practical application so far. Korean patent KR1019930003328 discloses a paper for cigarette filter rods with improved water resistance and elasticity, and KR1019950001962 discloses a sheet for cigarette filter rods with improved hardness and elasticity. Improve the elasticity of filter tip, but in view of it has all adopted wet papermaking, will certainly cause significant environmental pollution. Because many additives must be added in the wet papermaking process, such as polyethylene oxide, cationic polyacrylamide, aluminum sulfonate, cellulose, etc. mentioned in the patent, these will not only affect the smoking taste of cigarettes, some even Also has certain toxicity. "Dry-laid paper cigarette filter rod and its preparation method" (application number 200510024998.X), invented a filter rod made of puffed dry-laid paper. Dry-laid paper is also commonly called dust-free paper or wood pulp non-woven fabric in China. Although it solves most of the problems of the above-mentioned materials, and has the advantages of uniform filter rod space, convenient molding, and low cost, its air permeability and adsorption rate are equivalent to those of filter rods made of acetate fiber. However, some deficiencies have been shown in the actual use process. For example, although the hardness of the filter rod has reached the relevant national standards, the pinching during the cigarette smoking process and the moisture in the smoke will reduce the elasticity of the filter tip, thereby affecting Filtration rate and odor absorption have a certain impact.

Contents of the invention

The purpose of the present invention is to solve some of the above-mentioned problems and deficiencies, and to provide a cigarette filter that can effectively reduce the direct harm of tobacco to smokers, and can improve the filtration rate while maintaining ideal resilience and reducing production costs. Preparation.

The technical solution of the present invention is realized in the following way: the dry-laid cigarette filter rod is composed of the filter element base material and the forming paper. The base material of the filter element is a bulky and highly elastic dry-laid paper made of wood pulp fibers and 5% to 65% of hot-melt sheath-core fibers, and the specific manufacturing method is as follows. First, use non-toxic esters or ethers to carry out antistatic treatment on the surface of the hot-melt sheath-core fiber, so that the specific resistance is less than 9×10 ⁸ (Ω·cm). Subsequently, the opened wood pulp fiber and 5% to 65% heat-melting sheath-core fiber are respectively metered and transported and air-laid. It is heated and formed without pressure in the forming drying tunnel, and the drying tunnel is in a negative pressure state of 0.98 to 0.85 atmospheres. Then, spray glue on the formed dry-laid paper, the spraying amount is 3.5% to 7% of the weight of the dry-laid paper, and complete the drying, curing, and puffing processes at one time. After being shaped by cold air, the grammage is 35 g/ m ² to 75g/m ² , dry-laid paper with a thickness of 0.8mm to 3.5mm. Finally, the above-mentioned dry-laid paper is placed on the feeding device of the filter rod forming machine, and is directly formed into a rod by wrapping the forming paper on the filter rod forming machine.

The further technical solution of the present invention is achieved in the following way: the dry-laid cigarette filter rod is composed of the filter element base material and the forming paper. The base material of the filter element is a bulky and highly elastic dry-laid paper made of wood pulp fiber and 5% to 65% hot-melt sheath-core fiber. The hot-melt sheath-core fiber can choose PE/PP, LPET/PET, or PE/ PET, or a mixture of PE/PP and PE/PET. The specific production method is exactly the same as the above-mentioned method.

Because a proper amount of rigid hot-melt sheath-core fiber is added to the wood pulp fiber during processing, the finished air-laid paper is bulky and elastic, and its thickness is at least twice that of ordinary air-laid paper. At the same time, the new process of pressureless heating forming and ladder-like temperature difference drying, curing and puffing makes the air-laid paper feel plump and stiff, and is not easy to deform. After the rod is formed, not only the hardness can fully meet the national standard of the filter rod, but also the pinching and squeezing during the smoking process of the cigarette, and even the moisture in the absorbed smoke will not affect the elasticity of the filter, and can still maintain a good filter. Resilience.

The beneficial effect of the present invention is: adopting the dry-laid paper produced by plant fibers such as wood pulp and adding an appropriate amount of hot-melt sheath-core fiber, the filling amount of the filter element base material is equivalent to that of acetate fiber, but it is more natural, non-toxic, Environmental friendly;

The finished dry-laid paper prepared by the method of the invention has a grammage of 35g/m ² to 75g/m ² , a thickness of 0.8mm to 3.5mm, good air permeability, uniform voids, high strength and good elasticity. The adsorption rate of the produced filter rod can reach more than 43%, which is 3-5 percentage points higher than that of acetate fiber filter rod, and 11-13 percentage points higher than that of polypropylene fiber filter rod, which is more conducive to the adsorption of tar;

There is no need to open the fiber during processing, and it is not necessary to add cellosolve or fiber forming adhesive, which simplifies the filter rod manufacturing process, and the filter rod made has a full hand feel, good elasticity, high resilience, no peculiar smell, and no spicy taste;

The filter rod can be made by using an existing ordinary filter rod forming machine, and the appearance of the product is equivalent to that of the existing product, and is easily recognized by cigarette manufacturers and consumers. Especially in the process of smoking, it is not easily deformed after being pinched or even affected by the moisture in the absorbed flue gas, can maintain good resilience, and has low cost.

The present invention will be further described below in conjunction with each embodiment.

Detailed ways

Embodiment one

First, use non-toxic esters or ethers to carry out antistatic treatment on the surface of the hot-melt sheath-core fiber, so that the specific resistance is less than 9×10 ⁸ (Ω·cm). Subsequently, the opened wood pulp fiber and 5% to 65% heat-melting sheath-core fiber are respectively metered and transported and air-laid. The hot-melt sheath-core fiber can choose PE/PP, LPET/PET, or PE/PET, or a mixture of PE/PP and PE/PET. The web-formed paper web is heat-formed without pressure in the forming drying tunnel, and the drying tunnel is in a negative pressure state of 0.98 to 0.85 atmospheres, so that the dry-laid paper maintains a high bulkiness. Then, spray glue on the formed dry-laid paper, the spraying amount is 3.5% to 7% of the weight of the dry-laid paper, complete the drying, curing and puffing process at one time, and form a grammage of 35g/ ^m2 after being shaped by cold air ～75g/m ² , bulky and highly elastic dry-laid paper with a thickness of 0.8mm～3.5mm. If the ladder-shaped temperature difference drying tunnel is used for drying, curing and puffing, the effect will be better. Cut the dry-laid paper into strips according to the required width, place them on the feeding device of the filter rod forming machine, and directly wrap the forming paper on the filter rod forming machine to form rods. The air-laid paper filter rod made has a full hand feeling, good elasticity, and a hardness of about 89%±1, which fully meets the national standard for filter rods. When the length is 120mm, the suction resistance is 3600pa-3800pa, and the weight is about 0.75g-0.77g. Cut into 20mm long filter tip and install it on the cigarette, the measured filtration rate is 43%～45%. Cigarettes have pure taste, no peculiar smell, no spicy taste, and the aftertaste is clean. After several times of pinching, it still has ideal resilience.

Embodiment two

The dry-laid paper cigarette filter rod prepared by the method described in Example 1 adopts 35% PE/PP hot-melt sheath-core fiber, or a mixture of PE/PP and PE/PET hot-melt sheath-core fiber , the mixing ratio is: 5% to 95% PE/PP and 95% to 5% PE/PET to form a bulky and highly elastic dry-laid paper with a grammage of 45g/m ² and a thickness of 1.3mm. According to the requirements of the finished product, divide the dry-laid paper into strips with a width of 4 cm, and overlap three layers. Place the three layers of overlapping dry-laid paper on the feeding device of an ordinary filter rod forming machine, and directly wrap the forming paper on the filter rod forming machine to form a rod. The air-laid paper filter rod made has good air permeability, uniform mesh gap, good elasticity, strong resilience, full hand feeling, no shrinkage, hardness of about 89%, and all indicators meet the national standards for filter rods. When the length is 120mm, the suction resistance is 3750pa, and the stick weighs 0.77g. After the filter tip is cut into 20mm length and installed on the cigarette, the measured filtration rate is 45.1%, and the particulate matter in the filtered smoke is 1.5 mg more than that of the acetate fiber filter tip. The water vapor adsorbed in the process of pinching and filtering did not affect the rebound effect of the filter. Cigarettes have pure taste, no peculiar smell, no spicy taste, and the aftertaste is clean.

Claims (5)

1. A dry-laid cigarette filter rod made of filter element base material and molding paper, characterized in that said filter element base material is made of wood pulp fiber and 5% to 65% heat-melting sheath-core fiber. Loose high elastic dry-laid paper, the dry-laid paper has a grammage of 35g/m ² to 75g/m ² and a dry-laid paper thickness of 0.8mm to 3.5mm. 2. The dry-laid cigarette filter rod according to claim 1, characterized in that the hot-melt sheath-core fiber adopts PE/PP, LPET/PET, or PE/PET, or adopts PE/PP and PE/ Blend of PET. 3. The dry-laid cigarette filter rod according to claim 2, when the hot-melt sheath-core fiber adopts the mixture of PE/PP and PE/PET, it is characterized in that the PE/PP and PE/PET The mixing ratio is: 5% to 95% PE/PP and 95% to 5% PE/PET. 4. The airlaid cigarette filter rod according to claim 1 or 2, characterized in that when the grammage of the airlaid paper is 75g/m ² , the thickness of the airlaid paper is at least 1.20mm. 5. a method for preparing the air-laid cigarette filter rod described in claim 1, is characterized in that: A. Use non-toxic esters or ethers to carry out antistatic treatment on the surface of the hot-melt sheath-core fiber, so that the specific resistance is less than 9×10 ⁸ Ω·cm; B. Measuring and transporting the opened wood pulp fiber and 5% to 65% hot-melt sheath-core fiber respectively, and air-forming; C. Do pressureless heating and molding in the forming drying tunnel, and the drying tunnel is in a negative pressure state of 0.98 to 0.85 atmospheres; D. Spray glue on the formed dry-laid paper, the spraying amount is 3.5% to 7% of the weight of the dry-laid paper, and complete the drying, curing and puffing process at one time, and then the cold air is set to form a grammage of 35g/m ² ~ 75g/m ² , dry-laid paper with a thickness of 0.8mm ~ 3.5mm; E. Place the dry-laid paper with a weight of 35g/m ² to 75g/m ² and a thickness of 0.8mm to 3.5mm on the feeding device of the filter rod forming machine, and directly wrap the paper on the filter rod forming machine to form a rod.