JPH11279954A - Synthetic leather having special appearance and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a synthetic leather having suede-like depressed portions and projected portions comprising silver surface layers by reprocessing cells in a porous structure. SOLUTION: This synthetic leather having a special appearance is obtained by successively laminating a layer-like porous structure 2 comprising many cells and a silver surface layer 3 to the upper surface of a base fabric 1, applying a pattern press processing treatment to the obtained multi-layered structure 7 from the side of the silver surface layer 3 to form an uneven surface, shaving off the projected portions 8 of the uneven surface of the obtained multi-layered structure 7a from a surface AA, and subsequently heating the multi-layered structure 7b having the shaved projected portions 8a to restore the cells of the porous structure 2b compressed by the pattern press processing treatment, thus reversing the depressed portions 9a and the projected portions 8a of the uneven surface into projected portions and depressed portions, respectively. Thereby, the produced synthetic leather has the formed surface comprising the projected portions 4 whose surfaces comprise silver surface layers 3 and the suede-like depressed portions 5 in which the porous structure 2 is exposed to the outer air.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel synthetic leather, and more particularly, to a synthetic leather characterized in that the concave portions are suede-like and the convex portions are a grain surface layer, and a method for producing the same.

[0002]

2. Description of the Related Art Synthetic leather is used for clothing, footwear, bags, stationery, artificial flowers, furniture, walls, vehicles, etc. depending on its use. There are brushed leather, flocked leather, gold leather, etc., and their manufacturing methods, structures, properties, and the like are diverse. Conventionally, among these synthetic leathers, those having an appearance and feel similar to natural leather are known, and synthetic leathers having a foamed structure and subjected to various processes such as pressing or printing on a silver surface are also available. Many were known.

[0003] However, a cell having an appearance and a touch similar to that of natural leather has not been manufactured or commercialized by using open cells or foamed cells. This is because it is generally considered difficult to process once formed open cells or foam cells again.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a novel synthetic leather by reworking cells in a porous structure. Also,
Another object of the present invention is to provide a method for producing such a novel synthetic leather.

[0005]

In order to solve the above-mentioned problems, a synthetic leather according to the present invention has a base cloth, a layered porous structure provided on the base cloth, and an entire surface of the porous structure. A plurality of convex portions having a surface provided as a silver surface layer, and portions other than the convex portions on the porous structure are formed by forming concave portions exposing the porous structure. It is.

[0006] Here, the "base cloth" is a base that supports synthetic leather such as cotton, synthetic fiber, and non-woven fabric. Further, the “porous structure” means a portion forming a porous layer such as an open cell structure or a foam cell structure. `` Silver surface layer '' means a layer with a gloss on the surface laminated on the porous structure, not only a glossy surface but also a layer with a matte finish or a printed surface included. Further, the “many convex portions” are not limited to those in which many fine convex portions are separated and scattered from each other, but also include those in which convex portions are connected to each other in a pattern. Any pattern may be used as long as the pattern and the recess are mixed together to form unevenness.

Further, the method for producing a synthetic leather according to the present invention is characterized in that a multilayer structure comprising a layered porous structure composed of a large number of cells and a grain surface layer are sequentially laminated on a base fabric, Forming a concave-convex surface by applying drawing from, shaving off the convex portion of the concave-convex surface, heating the multilayer structure, and restoring the cells of the porous structure compressed by the drawing,
The concave and convex portions of the uneven surface are reversed.

[0008] The term "multilayer structure" as used herein means a multilayer structure comprising a base fabric, a layered porous structure laminated on the base fabric, and a grain surface layer laminated on the porous structure. means.
The term “stretching” means a process of three-dimensionally forming an uneven pattern on the surface of the silver layer, and is synonymous with embossing or drawing. `` Forming an uneven surface '' means, for example, not only those in which a large number of patterns of a specific shape are arranged in a scattered pattern, but also those in which a continuous pattern is arranged in an uneven shape or a ground pattern is arranged in an uneven shape, What is necessary is just to be what was formed in the unevenness | corrugation on the surface of a silver surface layer. The term "shaving off the convex portion of the concave-convex surface" does not mean that the convex portion of the concave-convex surface is completely removed, but means that the convex portion is left and the convex portion is cut off. `` Sharpening '' means shaving the convex part, for example, making the suede-like leather raised by rubbing the back of chrome tanned leather with sandpaper, etc., especially if it can be made suede-like It does not limit the means.

Further, the multilayer structure can be manufactured by laminating a urethane resin on the surface of a wet base.

The term "wet base" as used herein refers to a base made of a polymer, such as a base having an open cell structure formed by applying a urethane resin to a base cloth and then eluted with a solvent DMF in water. It means a base having an open cell structure formed by applying a solvent and then extracting the solvent.

Further, the multi-layer structure may be a foam base obtained by laminating a sheet having a foam layer and a grain surface layer on a base fabric and foaming the foam layer by heating.

Preferably, the drawing is carried out by heating the multilayer structure at an ambient temperature of 80 to 230 ° C. and then drawing it cold.

Here, the "ambient temperature" is the temperature in the furnace when the multilayer structure is pressed.

The heating time at an ambient temperature of 80 ° C. to 230 ° C. is 10 minutes (at 80 ° C.) to 30 seconds (at 230 ° C.), furthermore, 110 to 190 ° C. for 5 minutes to 37 seconds, and furthermore The temperature is preferably from 140 to 150 ° C. for 60 to 40 seconds.

[0015]

According to the present invention, the surface of synthetic leather is formed by a large number of projections having a silver surface layer and suede-like depressions exposing a porous structure. A synthetic leather having a novel appearance can be provided. As a result, it becomes possible to provide synthetic leather having an appearance, texture, and feel similar to natural leather, so that synthetic leather that is similar in appearance and feel to luxury leather such as reptiles, lizards, snakes, and alligators can be provided. Manufacturing can also be realized.

Further, the method for producing a synthetic leather according to the present invention comprises:
After the multi-layered structure is subjected to the pressing, the convex portion of the uneven surface is scraped off to expose the porous structure and heated, thereby restoring the cells of the porous structure compressed by the pressing, and the uneven surface is formed. Since the concave portions and the convex portions are reversed, it is possible to produce a novel synthetic leather in which the above-described silver surface layer is a convex portion and the concave portion is a suede-like.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the synthetic leather according to the present invention will be described below with reference to FIGS. FIG.
Is a cross-sectional view of a synthetic leather according to an embodiment of the present invention, FIG.
Is a plan view thereof. As shown in FIGS. 1 and 2, the synthetic leather of the present embodiment includes a base cloth 1, a layered porous structure 2 provided on the base cloth 1, and the entire surface of the porous structure 2. The surface provided is composed of a number of convex portions 4 having a silver surface layer 3, and a portion other than the convex portions 4 on the porous structure 2 forms a concave portion 5 exposing the porous structure 2. It is characterized by the following.

Next, the method for producing synthetic leather according to the present invention will be described by using a wet base and a foam base.

A method for producing synthetic leather using a wet base will be described with reference to FIGS. FIG. 3 is an explanatory view showing a method of manufacturing a synthetic leather according to the present invention using a wet base, and FIG. 4 is a manufacturing process diagram using a wet base.

A polyester base urethane, a polyether type urethane, a polycarbonate type urethane, or the like is applied to the base cloth 1 as a wet base polymer, and the solvent DMF is eluted in water to form a wet base 6. One to three layers of urethane resin are laminated thereon using a release paper as a liner. At that time, in each laminating step, a film to be a silver surface layer 3 by volatilizing a solvent contained therein is laminated on a wet base 6, and the same day or After aging for two days, the release paper is peeled off to form the multilayer structure 7.

Next, drawing is performed using the multilayer structure 7. At this time, if a heat roll is used, the cells of the porous structure 2 are broken and the resilience is poor.
, The multilayer structure 7 is heated and pressed at a cold squeezing roll temperature of 10 to 50 ° C. Ambient temperature is 80-2
30 ° C., even 110-190 ° C., and even 14
The temperature is preferably from 0 to 150 ° C. The heating time is preferably about 10 minutes at 80 ° C. and about 30 seconds at 230 ° C. according to the ambient temperature. Atmospheric temperature 110
The heating time is preferably from 5 minutes to 37 seconds at a temperature of ~ 190 ° C, and from 60 seconds to 40 seconds at an ambient temperature of 140 to 150 ° C. At this ambient temperature, the cells of the porous structure 2a are only compressed and not broken. Thereafter, the protruding portion 8 of the multilayered structure 7a which has been squeezed is scraped off to the AA surface with sandpaper or a slicer such that the cell of the porous structure 2a is exposed and the protruding portion 8 and the concave portion 9 remain. As a result, a multilayer structure 7b having the convex portions 8a and the concave portions 9a is obtained. Thereafter, processing such as printing or lamination of a metal foil may be performed according to the purpose.

Next, the process proceeds to the step of restoring the cells of the compressed porous structure 2b of the multilayer structure 7b. The restoration is performed by heating in a furnace having an atmosphere temperature equal to or higher than the amount of heat applied at the time of drawing or higher than the softening point of the urethane resin used (heat source is electric heat, gas, or the like). This step can also be performed by fir-releasing with a fir machine that can be heated with gas, hot water, or the like. Due to the restoration of the cells of the porous structure 2b, the convex portions 8a become the concave portions 5, and the concave portions 9a become the convex portions 4, and the convex portions and the concave portions are reversed. As a result, a synthetic leather whose surface is formed by the convex portions 4 whose surfaces are a silver surface layer and the concave portions 5 in which the porous structure 2 is exposed and becomes suede-like is obtained. Thereafter, depending on the purpose, the silver surface layer 3 on the convex portion 4 may be subjected to various processes, that is, processes such as printing, surface treatment, and lamination.

Example 1 for producing a wet-based synthetic leather
Shown in

Example 1 A twill-woven raised cloth using tetron / rayon yarn was used as a base cloth, and a polyester-based urethane resin (Dainippon Ink Crisbon 8116) 100 was placed thereon.
Parts, DMF 70 parts, cell adjustment additive (Dainippon Ink SD11
Or SD-7B or Nippon Paper KC Frock W300) 12
850 g / m ² (dry weight 80 g / m ² , viscosity of 3000 cps by BM type viscometer) with 5 parts by weight of a pigment (Dainichi Seika BS1000 series) and 5 parts by weight of DM in water
F was extracted and made wet base through the drying process.

Next, a one-pack polyester type urethane resin (Seiko Kasei U2300) 100 was used as a silver surface layer on release paper.
80 g / m ² (dry weight 12.4 g / m ² , viscosity of 300 with a BM type viscometer)
0 cps) and dried at 80 ° C. ambient temperature for 60 seconds. Next, one-pack polyester urethane resin
100 g / m ² (dry weight: 18.9 g / m ² , viscosity: 3,000 cps using a BM viscometer) were applied by mixing 00 parts, 35 parts of DMF, 35 parts of MEK, and 30 parts of a pigment, and in a drying furnace at an ambient temperature of 130 ° C. After drying for 60 seconds, the laminate was thermally laminated with the above wet base. After aging for 24 hours, the release paper was peeled off.

Next, drawing was performed. The squeezing condition is as follows. The multilayer structure is heated for 60 seconds in a furnace at an atmospheric temperature of 140 ° C. using electric heating, and pressed by a squeezing roll through cooling water for 3 k
g / cm ² at a speed of 4.5 m / min. After that, the convex portion was scraped off with a 150M sandpaper.
By scraping, the cell layer was exposed and became suede-like. Next, 4.5 m in a furnace having an atmosphere temperature of 150 ° C.
The cells were restored to the original state by passing the cells at a speed of / min. As a result, the convex portion and the concave portion were reversed, the concave portion was suede-like, and the convex portion became a grain surface layer. This semi-finished product was subjected to a surface treatment to obtain a final product.

Next, a method for producing synthetic leather using a foam base will be described with reference to FIG. FIG. 5 is a manufacturing process diagram using a foam base.

A foamed layer and a film having a silver surface which is a non-foamed layer, for example, a vinyl chloride resin, are bonded to the base fabric by a topping and / or paste method using a calender. This is passed through a foaming process to produce a foamed base. The number of the foaming agent in the foamed layer is made larger than the usual number in consideration of reheating by reheating. Then, it is squeezed by squeezing in the same manner as in the production of synthetic leather using a wet base. Also in this case, the surface of the silver layer, which is a non-foamed layer, is heated and squeezed with a cold squeezing roll. Thereafter, the silver surface of the convex portion is scraped or cut with sandpaper or a slicer until the cell having the foamed structure is exposed. Depending on the purpose, various processes, for example, processes such as printing and lamination of mylar may be performed. Next, the compressed cells having the foamed structure are restored to the original state. As the means, heat is applied to the extent that the residual foaming agent is partially decomposed. However, over a long period of time, harmful effects such as squeezing and melting of the cells having an exposed foamed structure are not preferred. Thereafter, post-processing (printing, surface treatment, etc.) may be performed according to the purpose.

Example 2 of a production example of synthetic foam-based leather
Shown in

Example 2 Using a rayon yarn and a plain woven cloth as a base cloth, an undercoating paste (Nissin Chemical Industrial Vinyl Blanc 381) was applied to adhere to a vinyl chloride layer. Foamed layer (film thickness 30/100 mm) and non-foamed layer (film thickness 12/100 mm) on the base fabric subjected to the undercoating treatment
Was topped with a calendar machine. Foam layer is 100 parts of vinyl chloride resin (Shin Daiichi PVC ZEST-1000Z), DOP
(Kyowa Hakko DOP) 60 parts, Ba-Zn (Akishima Chemical No.6565) 2.5 parts as a stabilizer, filler (Nitto Powdered SS-80) 4
0 parts, 6 parts of foaming agent (Otsuka Chemical AZH), non-foamed layer, vinyl chloride resin (Shin Daiichi PVC ZEST-1000) 100
Part, DOP (Kyowa Hakko DOP) 80 parts, Ba as stabilizer
-2.5 parts of Zn (Asahi Denka AC-186 or AP-548) and 10 parts of filler (Nitto Powdered SS-80) were used. Foaming was carried out by passing the topped fabric in an oven at 230 ° C. for 60 seconds to produce a foamed base.

Next, squeezing was performed using a foam base.
Heating is performed with a heat amount (at an ambient temperature of 150 ° C. for 40 seconds) at which the surface of the vinyl chloride layer is slightly softened by electric heating,
It was squeezed with a cold squeezing roll passing cooling water at a rate of 4 kg / cm ^{2 at} a speed of 4 m / min. Next, the foamed cell layer was scraped off with a 120M sandpaper until the foamed cell layer was exposed to give a suede-like appearance. Thereafter, a heating step was performed to restore the cell. The heating was performed by electric heating at a surface temperature of the vinyl chloride layer of 180 to 200 ° C. for 40 seconds. At this point, the cell was restored, but the suede surface was melted by heating and the suede feeling was somewhat impaired. Thereafter, printing and surface treatment were performed to obtain a final product.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a synthetic leather according to an embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is an explanatory view showing a method for producing a synthetic leather according to the present invention using a wet base.

FIG. 4 is a manufacturing process diagram using a wet base.

FIG. 5 is a manufacturing process diagram using a foam base.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base cloth 2 Layered porous structure 3 Silver surface layer 4 Finished part of completed synthetic leather 5 Concave part of completed synthetic leather 6 Wet base 7 Multilayer structure 8 Stretched convex part 9 Stretched concave part

Claims (5)

[Claims] 1. A base fabric comprising: a base fabric; a layered porous structure provided on the base fabric; and a large number of convex portions having a surface provided over the entire surface of the porous structure and having a silver surface layer. Synthetic leather characterized in that a portion other than the convex portion on the porous structure forms a concave portion exposing the porous structure. 2. A multi-layered structure in which a layered porous structure composed of a large number of cells and a grain surface layer are sequentially laminated on a base fabric, is subjected to squeezing from the grain surface layer side to form an uneven surface. Forming, shaving off the convex portion of the uneven surface, and then heating the multilayer structure,
A method for producing synthetic leather, comprising restoring the cells having the porous structure compressed by the drawing process, and inverting the concave portions and the convex portions of the uneven surface. 3. The method for producing synthetic leather according to claim 2, wherein the multilayer structure is produced by laminating a urethane resin on a surface of a wet base. 4. The multi-layer structure is a foam base obtained by laminating a sheet having a foam layer and a grain surface layer on a base cloth, and foaming the foam layer by heating. 3. The method for producing a synthetic leather according to 2. 5. The method according to claim 1, wherein the multilayer structure is heated to an ambient temperature of 80 to 23.
The method for producing synthetic leather according to claim 2, wherein the drawing is performed by cold drawing after heating at 0 ° C.