CN100423664C - Reinforcements used in footwear - Google Patents

Abstract

The present invention relates to a reinforcing material composition for use in the manufacture of footwear products, the composition incorporating a hardener and a binder, and a method for its preparation.

Description

Reinforcements used in footwear

This application claims priority to US Provisional Patent Application No. 60/584,519, filed July 1, 2004, and US Provisional Patent Application No. 60/640,947, filed December 31, 2004.

technical field

The present invention relates to stiffeners, such as stiffeners for maintaining the shape of the heel and toe portions of an article of footwear during the manufacture of footwear.

Background technique

A large number of different types of reinforcements are used in the shoe industry. U.S. Patent Nos. 3,523,103, 3,590,411, 3,647,616, 3,891,785, 3,973,285, 4,814,037, 6,391,380, and 6,475,619 disclose methods and materials for improving the hardness and adhesion of materials used in the footwear industry (all of which are incorporated herein by reference). The hardened plastic resin is selected from styrene butadiene, polystyrene, polyvinyl acetate, acrylic, and other polymer lattices that can be impregnated into the needle-punched nonwoven fabric. Some of these reinforcements are coated on their surfaces with hot melt adhesives and bonded to the upper and lining by heat activation. There are hot melt adhesives that activate with solvents and do not have heat activation. Another type of reinforcement is a pre-molded material made of polyvinyl chloride, ionomer or thermoplastic rubber (TPR). These preformed reinforcements require an adhesive to be applied on the surface to bond with the shoe components. Some reinforcements are manufactured by extruding a resin such as an ionomer or other thermoplastic polymer and then extrusion coating the resulting polymer sheet with an adhesive. A final class of reinforcements includes those made from powders of fillers or mixtures of hard materials and binders or softer materials. These polymer powder mixtures are then heated and sintered to produce reinforcements.

Desirable properties of a stiffener are high resilience and good stiffness for a given material weight. Saturated stiffeners can be made stiff, but generally harder grades do not have high resilience. Infiltrated reinforcements, preformed reinforcements, and extruded reinforcements all require an additional processing step of applying adhesive to the surface. Powder-coated reinforcements typically require cryogenic grinding capable of grinding the low-melting binder into a fine powder, which results in increased cost and requires a critical particle size distribution. Because powder-coated materials are sintered, they are not very strong or strong, and additional weight is required to achieve a given level of stiffness because a true material melt that maximizes physical properties cannot be formed by sintering. These materials also require substantial amounts of adhesive components in order to form a good bond with the various substrates to which they will be adhered. This results in higher cost and higher weight. When hot melt impregnating materials or extruding materials, they require a significant amount of hot melt adhesive to be applied to their surface in a separate step.

There are processes and products used in the packaging industry where an adhesive tie layer is added to another resin, creating a very thin layer that bonds the various layers together. Typically, an adhesive tie layer is used in which the adhesive component is similar in melt viscosity and melting point to the other layers. The method used to prepare these materials is extrusion, where multiple extruders and multi-component modules or manifold dies are used.

Contents of the invention

The present invention overcomes a number of the above-mentioned disadvantages. The present invention uses a hardening plastic resin such as polyethylene terephthalate glycol (PETG) copolyester polymer and a low-melting plastic binder resin such as polycaprolactone to form simultaneous Polymer reinforcement sheet with hardening and adhesive properties. PETG copolyester polymer and polycaprolactone can be combined in different ways to obtain the desired hardening and adhesive properties.

Additional hardening plastic resins are well known in the art, examples of which are styrene resins, styrene-butadiene resins, vinyl acetate resins, vinyl chloride resins, acrylic resins, extruded thermoplastics or thermally coated powders. Plastic materials, which may be selected from polyvinyl chloride, ionomers, high, medium or low density polyethylene, polypropylene, polyester, polystyrene, and copolymers and compatible blends of these polymers. Examples of commercially available hardeners are PETG, PET and copolyesters such as but not limited to GP001 polyester, all of which are available from Eastman Chemicals.

GP001 is a copolyester with a Vicat softening temperature of 74°C and a glass transition temperature of 75°C. At a thickness of 10 mils, the GP001 copolyester film has a density of 1.30 g/m ³ , an Elmendorf tear resistance of 7.5 N (MD and TD), and a PPT tear resistance of 61 (MD. ) and 66N (TD.), the tensile strength at break is 53Mpa (7600psi under MD and TD), the tensile modulus is (MD) 1570Mpa (2.3×10 ⁵ psi) and (TD) 1560 (2.3×10 ⁵ psi), the projected (dart) impact at 23 ° C is 355 grams, the elongation at break is 5% (MD and TD), and the tear propagation resistance (Tear Propagation Resistance) (split tear method) (at 254 mm/min) (MD and TD) is 15.7N. The mechanical properties of GP001 during injection molding are as follows: the tensile stress at break is 3200 psi, the tensile stress at yield is 7400 psi, and the elongation at break is 184%, the tensile modulus is 3.3×10 ⁵ psi, and the flexural yield strength is 10600 psi.

Polycaprolactone has good resistance to water, oil, solvents and chlorine. Polycaprolactone has a low melting point (58-60°C) and low viscosity, and is easy to process. Other low-melting additional plastic binder resins, such as plastic resins having a melting point below 85°C, may also be used in the present invention. An example of an additional low melting point plastic binder resin is ethylene methyl acrylate copolymer sold by Eastman Chemicals as 2260EMAC. The melting point of 2260 EMAC is 76°C.

EMAC 2260 is an ethylene methyl acrylate copolymer with a melting index of 2.1g/10min, a density of 944 kg/m ³ , a Vicat softening temperature of 50°C, a brittleness temperature of <-73°C, and a durometer hardness (Shore D Grade) is 37, the methyl acrylate content is 24%, the tensile stress at break (500mm/min) is 11Mpa, and the elongation at break is 835%, and the melting point is 76-77°C.

The reinforcement can be evaluated to determine the bond strength of the final product by die cutting a piece of the reinforcement to be tested and inserting it between two sheets of 0.029 inch thick 35% polyester blend nonwoven between lining materials. The above three pieces of material were put together into a back part heel counter molding machine with a female mold at 180°F and a male mold at 290°F. The mold is closed and held in place for 17 seconds. The mold is opened and the resulting laminate is placed at room temperature in a laminate cooling station having the desired shape of the final product. The resulting shaped counter is rigid and the stiffener is bonded to two sheets of nonwoven liner material. The adhesion test requires that the three-part laminate remain bonded when the components are pulled apart by hand pressure. From this it is determined whether the hardened material has good adhesive properties. The resiliency test is based on making a thumbprint indent on the heel side and evaluating the degree of resiliency of the indent. Acceptable rebound is when the dent springs back immediately with a "ping-pong". From this it is determined whether the hardened material has resilience.

One method involves the formation of a polymer reinforcement sheet with both hardening and adhesive properties in one step by coextruding a binder such as polycaprolactone and a PETG copolyester using a coextrusion block or manifold die. The method and materials are unique in that they allow the use of two materials with significantly different melting points and viscosities to form a sheet in one step. These sheets are then thermally activated, bonding with the other shoe components when heated and molded, and at the same time creating a hard material according to the proportions of the components and their weight. A hard material with a high degree of resilience and toughness is produced according to the formulation. Two unique features of the products and processes described are their ability to coextrude two materials with widely differing melt indices and melting points into acceptable sheets. Additionally, it is more cost effective to accomplish in one step a process that would normally require two steps, and since the adhesive is always on both outer surfaces of the sheet, a smaller amount of adhesive resin can be used. It is also possible to use reground material to replace virgin polymer.

Another method involves mixing the polymer mixture of the copolyester with a binder such as polycaprolactone in a continuous mixer or extruder to form a dry mixture. A polymer reinforcement sheet having both hardening and adhesive properties is thus produced in one step. The unique methods and materials allow the use of two materials with significantly different melting points to form a homogeneous mixture. These sheets are then thermally activated when heated and molded, bonding them to the shoe part and at the same time creating a hard material according to the proportions of the components and their weight. A hard material with a high degree of resilience and toughness is produced according to the formulation.

Detailed ways

The copolyester in the coextruded reinforcement is preferably Eastman Chemical Eastar 6763 with a softening point of 85°C (185°F), and it is typically extruded at an extrusion temperature of 246-274°C (475-525°F) Extrude into film. The binder is preferably polycaprolactone, and most preferably Dow Chemical Tone 767 (Tone) with a melting point of 60°C (140°F) and a melt flow of 1.9 or Tone 787 with a melt index of 0.5. The melt index is measured at 80°C and 44 psi according to ASTM D1238-73, and the unit is g/10min. PETG has a flex modulus of 300,000 psi and Tone has a flex modulus of 63,000 psi. Therefore, PETG is the component that increases the stiffness of the material, and changing its level changes the level of stiffness. Tone is usually extruded at 93-120°C (200-250°F). The method and materials are unique in that the two materials are mixed together in the mold and they maintain their overall integrity. Tone is distributed on the outer surface as a binder, while PETG forms the inner core for added rigidity.

The use of the above two materials is for illustration only, the invention is not limited to these materials, and PET polyester can be coextruded as the core or ionomer, and the above adhesive, ethylene-vinyl acetate copolymer adhesive compound, vinyl methacrylate adhesive, or copolyester.

The following examples lead to several new findings. Manifold dies are ideal for forming "ABA" structures where the adhesive is on both sides of the polymer reinforcement. PETG regrind does not need to dry at ambient conditions of 75°F and less than 50% humidity. Tone can be operated at higher temperatures without losing too much viscosity and still produce a good coating. Casting rolls can be operated at a temperature of about 55°F. Tone feed tubes and extruders reduce and/or eliminate the potential for die score lines when using dies at higher temperatures. These score lines are from the adhesive coating and not from the hardened polymer. Using a flex lip die and a 100 mesh screen pack helps to give a better surface and minimize contamination. Casting rolls worked well, but gauge control was not possible with these rolls. Thickness control depends on extruder speed and die diameter. There is a limit to how much turn down you can get with one lip, and mold modifications can be made to increase the amount of turn down. Good bonds are obtained with Tone Coat and Tone Coat remains on polymer surfaces even at elevated temperatures. Using a PETG/Tone ratio of 90/10, good adhesion can be obtained even when the Tone layer dosage is below 50g/ ^m2 . Dry PET regrind can also be used with Tone in this invention, but it needs to be extruded at higher extrusion temperature and higher mold temperature. Polyethylene terephthalate (PET) requires a PET extruder temperature of at least 550°F, which results in good tone flow and good bonding.

The following examples illustrate the method of the invention and the materials prepared according to the method.

Examples 1-9 relate to a method of mixing a polymeric hardener and a binder material in one mixing and/or extrusion step to produce a polymeric reinforcing sheet.

Example 1

The copolyester was PETG copolyester, specifically Eastar 6763 from Eastman Chemical, and the binder was polycaprolactone, specifically Tone 767. These two materials have significantly different properties, but can be processed to homogeneity by passing them through a READCO continuous mixer (READCO Company, York, PA.) at a temperature range of 380-400°F. The device does not require materials in powder form and can use materials that are different from each other to form a homogeneous melt that is used to form sheets with toughness, rigidity and adhesive activity. 40 parts of Tone 767 and 60 parts of PETG copolyester were added separately to a 2 inch READCO continuous mixer set at 375°F and a slot die temperature of 425°F. The feed rate was 60 lbs/hr and the screw speed was 150 rpm. The resulting sheet was passed through a set of chill rolls to give a sheet thickness of 40-43 mils.

Example 2

This example has the same conditions as Example 1, except adding 50 parts of Tone and 50 parts of PETG to the mixer to produce a sheet of the same thickness.

Example 3

This example had the same conditions as Example 1, except that 60 parts Tone and 40 parts PETG were used to produce sheets with a thickness in the range of 40-43 mils.

Example 4

This example has the same conditions as Example 1 except that 60 parts Tone and 40 parts PETG are used to produce a sheet thickness of approximately 60 mils.

Example 5

This example had the same conditions as Example 1 except that 50 parts Tone and 50 parts PETG were used to produce a 60 mil thick sheet.

Example 6

This example has the same conditions as Example 1 except using 40 parts Tone and 60 parts PETG to produce a 60 mil thick sheet

Example 7

This example had the same conditions as Example 1 except that 40 parts Tone and 60 parts PETG were used to produce an 80 mil thick sheet.

Example 8

This example had the same conditions as Example 1 except that 50 parts Tone and 50 parts PETG were used to produce an 80 mil thick sheet.

Example 9

This example had the same conditions as Example 1 except that 60 parts Tone and 40 parts PETG were used to produce a 70-75 mil thick sheet.

The stiffness and resilience of the materials made from Examples 1-9 were measured using Satra measurement procedure #TM 83. This measurement method is the standard method used in the footwear industry. The results are shown in Table I below.

Table I - Stiffness and Resilience

Example number 1 2 3 4 5 6 7 8 9 Wt.(g/m²) 1293 1344 1317 1627 1741 1867 2511 2496 2236 Thickness (mils) 40-42 41-46 42-43 52-57 54-57 60-62 80-83 80-84 73-75 1^st collapse (kg) 17 16.5 11.4 19.7 26.4 37.1 63.2 51.8 43 10^th collapse (kg) 12.4 9.6 7.7 14.2 16.6 24.5 40.4 38.6 28.9 % Resilience 73 58 68 72 63 66 64 75 67

Examples 10-25 relate to a method of coextruding a polymeric hardener and a binder material in a single extrusion step to produce a polymeric reinforcement sheet.

Example 10

Two WELEX extruders with WELEX coextrusion modules were used in this example. Use sheet dies with a maximum gap of 40 mils. A ^2-1 / ₄ inch WELEX extruder was used to extrude the PETG core material with temperature profiles of 325°F, 350°F, 375°F and 400°F. The mold temperature was maintained between 390°F-410°F. And evaluate the temperature distribution at 325°F, 375°F, 410°F, and 420°F. PETG in the form of reground chips was used as feed to the extruder. The second extruder was a 1 inch WELEX extruder using Tone pellets. The second extruder was maintained at a temperature profile of 165°F, 230°F and 255°F. PETG was added to the center of the coextrusion module, and Tone was added to the two outer regions. The resulting product was a 33 mil thick sheet, and the resulting product was extruded onto a chill roll pack of 3 chill rolls and wound. The extrusion rate of PETG was kept at 72#/hr, and the extrusion rate of Tone was changed to obtain products with PETG/Tone ratios of 70/30, 80/20 and 90/10. The ratio of 70/30 is derived from the extrusion rate of PETG of 72#/hr and the extrusion rate of Tone of 30#/hr, while the ratio of 90/10 is derived from the extrusion rate of PETG of 72#/hr and the extrusion rate of 7.8#/hr Tone extrusion rate. Tone is formed on both sides of PETG. The sheet samples were placed on a temperature changing melting point block apparatus, and the surface tackiness of the sample sheets was measured by touching them at different temperatures. All samples were measured to have good tack properties at 60-100°C (140-212°F), implying a Tone on the surface. Samples will not be tacky at these temperatures if there is no Tone on the surface. A sheet sample was removed and placed between a piece of leather and the lining material, which was then placed in a mold with a bondline temperature of 70°C (150°F) and the material compressed. PETG/Tone material forms an excellent bond to leather and lining.

Surprisingly the low melting point resin did not dissolve in the high melting point resin and the adhesive remained intact and formed a separate coating on the PETG.

31-33 mil sheet samples were cut into circles and molded into dome-shaped blocks and tested for stiffness and resiliency by the Satra dome test. Table II presents the data obtained.

Table II - Stiffness and resilience of Example 10

Wt.(g/m²) 1035 Thickness (mils) 31-33 1^st collapse (kg) 15.3 10^th collapse (kg) 14.5 % Resilience 95

Example 11

Three extruders were used in this experiment. Two of them are Crompton Davis standard ^1-1 / ₄ -inch extruders and the other is a ^2-1 / _2- inch extruder. The larger extruder fed PETG at a constant rate, while two smaller extruders were used to feed Tone. The material was fed into a manifold sheet mold with the center receiving the PETG melt and the two outer layers receiving the Tone.

The equipment used is as follows:

Extruder: A ^2-1 / ₂ inch Davis standard extruder with a 30/I L/D single stage barrier screw. Five heating and cooling zones. Two ^1-1 / ₄ inch Davis standard extruders with 24/I L/D barrier type single stage screws. None of the extruders had gear pumps or static mixers. Above the 2- ^1/2 _inch extruder is a gravity feeder. Two ^1-1 / ₄ -inch extruders feed the sides of the die, while a ^2-1 / ₂ -inch extruder feeds the center of the die. All extruders had throat cooling and the throats were cooled to 50°F;

Mold: Three-layer branched tube flexible lip mold with separate heating on the outer tube and the center of the mold and on the lip. The die was a 12 inch wide EDI unit with a coextrusion module for ABA coextrusion. The filter changer on all machines has a 20/100/20 mesh filter set;

Rolls: two casting rolls are parallel to each other on a 30-inch horizontal plane, and have cooling devices on both rolls;

Thickness monitor: β-type gauge (gauge);

coiling section;

Cutting table with paper cutter for slicing;

Cooling unit: for rolls and extruders.

(Note: Thickness is controlled by the die lip and not by the rolls. Use the take-up unit to adjust the thickness during start-up until equilibrium is reached, then bypass the take-up section and send directly to the cutting table, cut about 3 feet long material).

Feed the undried PETG into _the 2 ^1/2 inch extruder. Undried Tone _{was added to the feed hopper and fed into each 1 1/4} ^inch extruder and PETG regrind was added to the ₂ ^1/2 extruders, started at 10 rpm. The extruder was maintained at temperatures of 325°F, 375°F, 400°F, 410°F and 420°F. Filter changers, fixtures and other piping maintained at 410°F. The output is 46#/hr. The feed throat was maintained at 50°F. The mold was maintained at 400°F. The lip heater was maintained at 100% and an air knife was also used. There were no significant score lines in the extrudate or PETG sheet.

The Tone extruder was set at 150°F, 230°F, and 250°F and the die was at 250°F. The coextruder was set at 18/11/11 rpms (PETG/Tone A/Tone C) to achieve a throughput of 154#/hr. The roll temperature was set at 45°F. Die spacing was set at 50 mils. The roll temperature was then raised to 55°F. This produced a 10 ^1/2 _inch wide sheet with the Tone coated portion approximately 7 ^1/2 _inches wide. The pressure in the PETG extruder was 2065 psi, the pressure in the Tone A extruder was 574 psi, and the pressure in the Tone C extruder was 387 psi. The roll speed was set at 7.5 fpm. The melt temperature was set at 397°F. Air knives are placed at the die exit and help cool the sheet before it is transferred onto the rolls. The process is capable of producing sheets with a thickness of 53-55 mils and a weight of about 1700 g/ ^m2 , sheets with a thickness of 51-56 mils and a weight of about 1611 g/ ^m2 , and sheets with a thickness of 45-48 mil and weighs about 1500 g/ ^m2 . All three materials were tested on fusing blocks and found to have good adhesion at 70-90°C (158-194°F).

There is a pressure differential between the two Tone extruders because of the long run time from the pipe to the die.

The following examples illustrate the different formulations evaluated and the measurements made on the final sheets produced.

Example 12

Samples of this example were prepared according to Example 11, but the extrusion rate was reduced to 16/10/10 rpm, producing a sheet having a thickness of 40 mils and a weight of about 1300 g/ ^m2 . Extrusion pressure was 1896 psi for PETG and 539 psi and 341 psi for Tone A and Tone C extruders, respectively. The temperature of all melt channels was set at 400°F, the mold temperature was set at 400°F and the roll speed was set at 7.5 fpm. A sheet having a thickness of 11 inches was obtained. Two types of wafers were obtained: one was 42-45 mil thick and weighed 1306 g/m ² ; the other was 40 mil thick and weighed 1273 g/m ² .

Example 13

Samples of this example were prepared according to Example 12, but the extrusion rate was reduced to 14/9/9 rpm, producing a sheet having a thickness of 35 mils and a weight of about 1000 g/ ^m2 . A thickness of 36-38 mils yields a weight of 1131 g/ ^m2 . The samples of this example produced a very good bond on the frit block and were tested sandwiched between two sheets of liner. The extrusion pressure on the PETG extruder was 1678 psi, Tone A was 499 psi, and Tone C was 313 psi.

Example 14

Samples of this example were prepared according to Example 13, but the extrusion rate was reduced to 12/8/8 rpm, producing a 30 mil thick sheet. Extrusion pressure was 1643 psi for PETG and 472 psi and 279 psi for Tone A and Tone C extruders, respectively. The melt temperature was set at 396°F. The roll speed was set at 7.5 fpm. The mode gap was set at 30 mils. A sheet having a thickness of 32 mils and a weight of 964 g/ ^m2 was obtained. Sheets with a thickness of 25-28 mils and a weight of 762 g/ ^m2 were also produced.

Example 15

Samples of this example were prepared according to Example 14, but the extrusion rate was reduced to 10/7/7 rpm, resulting in a sheet thickness of 23-25 mils. This example produced a very good bond when tested on a frit block. The extrusion pressure was 1314 psi for the PETG extruder, and 432 psi and 243 psi for the Tone A and Tone C extruders, respectively. The melt temperature was set at 396°F and the roll speed was set at 7.5 fpm.

Example 16

Samples of this example were prepared according to Example 15, but the extrusion rate was reduced to 8/6/6 rpm, resulting in a sheet thickness of 20 mils. Additionally, the extrusion rate was set at 9/6/6 rpm to give a sheet thickness of 17-20 mils. This example produced a very good bond when tested on a frit block. Sheets with a thickness of 16-22 mils had a weight of 508 g/ ^m2 . Table III and Table IV below give the results of the dome test for Examples 11-16 above.

The spherical top test result of table III embodiment 11-16

Material PETG/Tone 90/10 90/10 90/10 90/10 90/10 Thickness (mils) 32 40 17 41-42 49-50 Thickness (mm) 0.81 1.01 0.43 1.04-1.07 1.24-1.27 Weight (kg/m²) 964 1273 523 1297 1592 1^st collapse (kg) 10.1 20.4 3.2 20.0 43.1 10^th collapse (kg) 10.0 16.2 2.3 16.3 25.8 % Resilience 99 79 72 82 60 molding time 7 7 6 6 9

The spherical top test result of table IV embodiment 11-16

Material PETG/Tone 90/10 90/10 90/10 90/10 90/10 Thickness (mils) 34-37 46-50 47-51 36-38 36-39 Thickness (mm) 0.86-0.94 1.17-1.27 1.19-1.29 0.91-0.96 0.91-0.99 Weight (kg/m²) 1089 1561 1541 1152 1164 1^st collapse (kg) 12.0 31.6 35.5 16.1 17.0 10^th collapse (kg) 11.6 24.2 25.6 15.1 15.1 % Resilience 997 77 72 94 89 molding time 7 7 9 7 7

Example 17

Samples for this example were prepared according to Example 16. The extrusion rate of the extruder was kept at 9/7/7 rpm, but the die temperature was increased to 450°F and the PETG extruder temperature profile was set at 325°F, 425°F, 450°F, 450°F and 450°F °F. The extrusion pressure was 1394 psi for the PETG extruder and 440 psi and 250 psi for the Tone A and Tone C extruders respectively. The Tone extruder is maintained at the previous temperature profile. This embodiment reduces die score lines from Tone. In addition, this embodiment will not mix Tone into PETG. Additionally, the use of Tone in this example resulted in good viscosity, no roll sticking occurred and the material had good cohesive properties.

Example 18

The samples of this example were prepared according to Example 17, but at the higher temperature the edges of the sheet made of PETG became very soft and the extrusion rate was set at 14/9/9 rpm to give a 35 mil thick Sheet. This embodiment does not produce die score lines.

Example 19

Samples for this example were prepared according to Example 18, but using polyethylene terephthalate (PET) (pre-dried) instead of PETG. The temperature profile on the extruder (previously used for (PETG)) was increased to 325°F, 425°F, 450°F, 450°F, and 450°F, and the die temperature was set at 450°F. The extruder extrusion rate was set at 14/9/9 rpm. The temperature profile of the Tone extruder was set at 175°F, 350°F, and 350°F, and the temperature of the melt tube was set at 400°F. This example produced sheets having thicknesses of 16-22 mils and 22-25 mils, respectively. In this example a non-uniform coating was produced from Tone and there were no die score lines.

Example 20

Samples of this example were prepared according to Example 19, but the PET extruder temperature was increased to 500°F and the die temperature was increased to 500°F. Extrusion rates were set at 24/12/12 rpm, extrusion pressure for PET was 193 psi, and pressures for Tone A and Tone C extruders were 591 psi and 354 psi, respectively. The melt temperature was 300°F. The fluidity is not good, but there are no scratch lines in the tone coating.

Example 21

Samples of this example were prepared according to Example 20, except that the temperature of the die and coextrusion block was raised to 550°F. The PET extruder temperature profile was set at 450°F, 500°F, 500°F, 500°F, and 500°F. The PET melt line temperature was set at 550°F. The temperature profile of the Tone extruder was set at 175°F, 350°F, and 350°F, and the temperature of the pipe was set at 300°F. The extrusion rate of the extruder was set at 14/9/9 rpm. The temperature of the tone exiting the die lip was between 300°F and 550°F and showed no die score lines.

Example 22

A sample of this example was prepared according to Example 21, but the extruder flow rate was increased to 24/15/15 rpm, resulting in a total output of 97#/hr. Then, reduce the speed to 24/12/12 rpms and place the resulting sheet on casting rolls. The extrusion pressure for the PET extruder was 144 psi, and for the Tone A and Tone C extruders were 596 psi and 340 psi, respectively. The roll speed was maintained at 7.5 fpm. This results in a good surface appearance and a Tone coating with very good adhesion. The thickness and weight of the sheet were measured to be about 29/31 mil and 1000 g/m ² , respectively. Very high temperatures do not harm Tone flow and eliminate die score lines. The sheet looked very good and had a width of 105/8 inches with the Tone coated portion being 91/8 inches. The weight of the material at a thickness of 35/36 mils is approximately 1200 g/m ² . With the roll temperature set at 55°F, no sticking occurred. The coated part is flexible. In the case that the Tone percentage is about 20%, the total output is about 112#/hr. The thickness of the resulting sheet was measured to be 34-36 mils and its weight was 1118 g/ ^m2 . Table V below shows the dome test results for Example 22.

Table V Ball Top Test Results of Samples Molded at 180°C for 2 Minutes

PET/TONE 80/20 Thickness (mils) 33-34 Thickness (mm) 0.84-0.86 Weight (kg/m²) 1081 1^st collapse (kg) 13.1 10^th collapse (kg) 12.9 % Resilience 98

Example 23

2260乙烯-丙烯酸甲酯聚合物来制造ABA结构。两个粘性外层是EMAC并且芯是GP001。使用由三台挤出机组成的共挤出模块系统。GP001在430°F下使用2英寸的Davis标准挤出机挤出，并且

在450°F下使用1¹/₄英寸Davis标准挤出机挤出。模温为420°F，并且使用22英寸的模具。GP001在挤出前预干燥。挤出物被浇铸到三辊浇铸系统上，挤出物送到中间辊上。调节模具和中间挤出机的速率形成各种片厚。生产出20、25、29、35、45和50密耳厚的片材。下面的表格列出了所生产的片材的球顶试验结果。A层总厚占最终产品总厚度的18％。下面的表VI给出了根据实施例23，在95℃下模塑8分钟制得的5个样品的球顶试验结果。根据实施例23在100℃下模塑7分钟制得的1个样品的球顶试验结果在下面的表VII中给出。Use Eastman GP001 polyester with a softening point of 74°C (165°F) and

2260 ethylene-methyl acrylate polymer to make the ABA structure. The two adhesive outer layers are EMAC and the core is GP001. A co-extrusion module system consisting of three extruders was used. GP001 was extruded at 430°F using a 2-inch Davis standard extruder, and

Extrude at 450°F using a 1 ^1/4 _inch Davis standard extruder. The mold temperature was 420°F and a 22 inch mold was used. GP001 is pre-dried before extrusion. The extrudate is cast onto a three-roll casting system and the extrudate is fed to intermediate rolls. The die and intermediate extruder speeds were adjusted to form various sheet thicknesses. 20, 25, 29, 35, 45 and 50 mil thick sheets were produced. The table below lists the dome test results for the sheets produced. The total thickness of the A layer accounts for 18% of the total thickness of the final product. Table VI below presents the ball top test results for 5 samples molded at 95°C for 8 minutes according to Example 23. The dome test results for one sample molded at 100°C for 7 minutes according to Example 23 are given in Table VII below.

Table VI Ball top test results of samples molded at 95°C for 8 minutes

samples A B C D E Thickness (mils) 19 24-25 27-29 44-48 48-50 Weight (kg/m²) 587 761 874 1436 1529 1^st collapse (kg) 2.2 4.4 6.7 30.0 37.3 10^th collapse (kg) 2.1 4.1 6.4 21.0 21.8 % Resilience 95 93 96 70 58

Table VII Ball top test results of samples molded at 100°C for 7 minutes

samples 35 Thickness (mils) 35-38 Weight (kg/m²) 1140 1^st collapse (kg) 15.1 10^th collapse (kg) 14.3 % Resilience 95

Example 24

The samples of this example were prepared according to Example 23, except that an ABA structure comprising a blend of 55% Tone and 45% GP001 was used as the "A" layer. Table VIII below reports the dome test results. All samples showed good adhesive properties.

Table VIII Ball Top Test Results of Samples Molded at 100°C for 7 Minutes

samples A B C Thickness (mils) 25-26 34-36 45-47 Thickness (mm) 0.63-0.66 0.86-0.91 1.14-1.19 Weight (kg/m²) 820 1116 1427 1^st collapse (kg) 8.9 18 34 10^th collapse (kg) 8.4 15.8 23.6 % Resilience 94 88 69

Example 25

The samples of this example were prepared according to Example 23, except that a blend comprising 55% Tone and 45% EMAC 2260 was used as the "A" layer. Table IX below presents the ball top test data. All samples showed good adhesive properties.

Table IX Ball Top Test Results of Samples Molded at 100°C for 7 Minutes

samples D E F Thickness (mils) 45-47 35-36 25-26 Thickness (mm) 1.14-1.19 0.89-0.91 0.63-0.66 Weight (kg/m²) 1399 1108 770 1^st collapse (kg) 27.3 14.2 5.1 10^th collapse (kg) 20.2 12.6 6.1 % Resilience 74 89 119

In order to disclose the present invention above certain preferred and alternative embodiments of the present invention, those skilled in the art can make modifications to the disclosed embodiments. Accordingly, the appended claims are intended to cover all embodiments of the invention as well as modifications which do not depart from the spirit and scope of the invention.

Claims (7)

1. A sheet-like reinforcing material for footwear, comprising a one-step extrusion composition comprising a low-melting plastic binder resin and a hardened plastic resin; wherein said sheet-like reinforcing material is included in said hardened A layer formed of the low-melting plastic adhesive resin on one or both sides of a plastic resin, and the low-melting plastic adhesive resin is not completely dissolved in the hardened plastic resin, and wherein the low-melting plastic adhesive The melting point of the synthetic resin is lower than 85°C. 2. The reinforcing material of claim 1, wherein said low-melting plastic binding resin is polycaprolactone resin, and said hardening plastic resin is polyethylene terephthalate glycol copolyester. 3. The reinforcing material of claim 2, wherein the volume ratio of polyethylene terephthalate copolyester/polycaprolactone is between about 70/30 and about 95/5. 4. The reinforcing material of claim 2, wherein the low-melting plastic adhesive resin and the hardened plastic resin are co-extruded through a co-extrusion module or a branch pipe sheet die. 5. The reinforcing material of claim 1, wherein said low-melting plastic binding resin is ethylene-methyl acrylate copolymer, and said hardening plastic resin is copolyester. 6. The reinforcing material of claim 1, wherein said low-melting plastic binding resin is a mixture of ethylene-methyl acrylate copolymer and polycaprolactone, and said hardening plastic resin is a copolyester. 7. The reinforcing material of claim 1, wherein said low-melting plastic binder resin is a mixture of ethylene-methyl acrylate copolymer and copolyester, and said hardening plastic resin is copolyester.