JPH0120273B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a leather-like sheet material that has excellent feel and appearance and good scratch resistance.

BACKGROUND ART Conventionally, sheet materials in which a polymer coating layer is provided on a fibrous base material such as a woven fabric, a knitted fabric, or a non-woven fabric coated with a polymer have been used as a substitute for leather. However, since the conventional sheet materials have a thick polymer coating layer, the texture of the leather is rubbery and has a strong rebound feeling, and the appearance is flat with no depth. On the other hand, some products have thinner polymer coating layers in order to eliminate these drawbacks, but they have poor durability and scratch resistance, and they also have problems when the unevenness of the substrate comes directly to the surface or when the coating is stretched. A satisfactory result has not yet been obtained, such as uneven stretching of the layer.

An object of the present invention is to provide a sheet-like material that has a full texture, feels like natural leather, feels good in the hand, has a deep appearance, and has good durability and scratch resistance. be. That is, the present invention has the following configuration.

That is, the leather-like sheet material of the present invention mainly includes a surface layer formed by mixing the tips of fluff fibers of 0.5 denier or less and a non-porous elastomer, and a surface layer that exists adjacent to the surface layer and mainly consists of the fluff. The present invention is a leather-like sheet-like material characterized in that it has an intermediate layer consisting of the base portions of fibers and substantially free of the elastomer on at least one side of the base layer.

An example of the leather-like sheet of the present invention is shown in FIG.

In FIG. 1, numeral 1 is a surface layer formed by mixing the tips of fluffy fibers and a non-porous elastomer. Having a surface layer formed by mixing the tips of fluff fibers and a non-porous elastomer means that the sheet surface is not covered with a single layer of elastomer, but a mixed layer of fluff fibers and elastomer is exposed. It means there is. For this reason, it is resistant to impact abrasions and scratches, and scratches are less noticeable.

2 is an intermediate layer consisting of the root portion of fluff fibers.

The intermediate layer consisting of the roots of the fluff fibers is a layer in which the roots of the fluff fibers are left unattached, and the density of the binding points (interlacing, bonding points, etc.) between the fibers is lower than that of the layers on both sides. This refers to the middle class.
In other words, if the layers on both sides are removed, the constituent fibers will be separated into individual filaments. 3 indicates the base layer. The reason why the sheet material of the present invention is flexible is that when stress is transmitted between the base layer and the surface layer, the intermediate layer acts as a buffer and absorbs the stress or delays the transmission. This is thought to be because the wood and surface layer can move independently.

In addition, in the present invention, the above-mentioned intermediate layer does not contain an elastomer, but within the range where the above-mentioned constituent fibers are separated into individual filaments and can exhibit a buffer band effect, There is no problem even if some elastomer is included.

FIG. 2 shows an example of the surface of the leather-like sheet of the present invention. The fibers are discernible under a microscope, but to the naked eye they appear silvery.

An example of a preferred cross section of the material sheet used in the present invention is shown in FIG. 3, and an example of the surface is shown in FIG. 4 is a fluff fiber, and only the fluff fiber is visible in FIG.

The fluff fibers referred to in the present invention are 0.5 denier or less,
It is preferable to have a length of 0.3 to 10 mm and a density of 100,000 lines/cm ² or more. If it is thicker than 0.5 denier, the rigidity is too high and the deformation on the base material side is directly transmitted to the surface layer side, which not only damages the flexibility of the sheet and the form of wrinkles on the surface, but also causes unevenness of fluff fibers to appear on the surface. , it is difficult to form a dense and supple leather-like surface because single fibers on the surface can be identified. Fluff fiber preferably less than 0.5 denier
Only by setting the denier to 0.2 denier or less can a sheet material having a surface layer with good smoothness, a thin thickness, and a good fit in the hand be obtained. Also, the length of the fluff is
If the length is shorter than 0.3 mm, the elastomer will easily penetrate to the root of the fluff, so the surface layer and base will become integrated.
The creases and flexibility of natural leather are lost. 10mm
If it is longer, the fluff is likely to be disturbed when forming the surface layer, and when the sheet-like product is pulled, uneven stretching due to the direction of the fluff tends to appear as unevenness on the surface. In other words, in order to eliminate these defects, the length of the fluff should be between 0.3 mm and 10 mm.
It is desirable to be in the range of mm. More preferable results are obtained when the thickness is in the range of 0.5 to 5 mm.

In addition, there are approximately 100,000 fluff fibers/fluff fibers on the base surface.
It is preferable to have a fluff density of cm ² or more.

If the fluff density is lower than 100,000 strands/cm ² , the surface of the substrate cannot be completely covered with fluff, resulting in uneven fluff, making the composite layer non-uniform and failing to provide a good appearance. In order to obtain a sheet-like material with a full texture, a feel like natural leather, and a deep appearance, the fluff density should be about 100,000 strands/cm ² or more, preferably about 200,000 strands/cm ² or more. is preferred.

The elastomer used for the surface layer is a synthetic resin or natural polymer resin such as polyamide, polyester, polyvinyl chloride, polyvinyl acetate, polyacrylonitrile, polyurethane, or a mixture of these resins. Furthermore, if necessary, plasticizers, fillers, stabilizers, pigments, dyes, crosslinking agents, etc. may be added. Polyurethane resins or polyurethane resins to which other resins and additives are added are particularly preferably used to obtain composite layers that have a soft texture and feel and have good bending resistance. Furthermore, resins such as two-component polyurethane which have a cross-linked structure and have good adhesion to fluff fibers are particularly useful for improving the scratch resistance and heat resistance of the surface layer.

The material sheet is a nonwoven fabric, a woven fabric, a knitted fabric, etc. using ultrafine fiber-forming fibers such as sea-island fibers, fine denier fiber bundles, peelable and splittable fibers, or a combination of these fibers with normal fineness fibers. . If necessary, a solution and/or dispersion of an elastomer or the like may be applied and solidified.
This material sheet has been subjected to treatments such as flocking, pile cutting, splitting, division, raising, buffing, etc. on at least one side, and has a fluff layer mainly consisting of ultrafine fibers of 0.5 denier or less, preferably 0.2 denier or less. is necessary.

Methods for forming a surface layer in which fluff fibers and elastomer are mixed on the outermost layer of the fluff layer include reverse roll coating, gravure coating, knife coating, spraying, etc. with a solution or dispersion of the elastomer onto the fluff layer of the base material. Directly apply an amount that permeates only the surface layer of the fluff layer, overlap it with a release sheet or roll surface, pressurize, heat as necessary, proceed with drying and crosslinking reaction, and release after the elastomer loses its fluidity. This method involves peeling off the sheet or roll surface.

The sheet material made in this way is dyed, embossed,
Treatments such as applying a finishing agent and rubbing may also be performed.

Embodiments of the present invention are shown below, but the present invention is not limited thereto. Unless otherwise indicated, percentages and parts are by weight.

Example 1 A 3-denier, 51-mm piece of polymer interlayer array fiber in a form in which one filament contains 52 ultrafine fibers with a binding component of 30 parts of polystyrene and an ultrafine fiber component of 70 parts of polyethylene terephthalate was used. A web was formed through a card and a cross wrapper, and then needle punched to create a nonwoven fabric. The basis weight of this nonwoven fabric is 480g/
m ² and apparent density was 0.21 g/cm ³ .

This nonwoven fabric was impregnated with a 15% aqueous solution of polyvinyl alcohol, dried, and then soaked in trichlorethylene and thoroughly washed to extract and remove polystyrene. The dried nonwoven fabric was impregnated with the following polyurethane solution. Softening point of 190 obtained by chain-extending a prepolymer of polycaprolactone and P,P' diphenylmethane diisocyanate with methane bisaniline.
After impregnation with a 10% DMF solution of polyurethane at 80°C, the sample was coagulated in water, thoroughly washed in hot water at 80°C, and dried. The unsliced side of the base material sliced to half the thickness of the second half of drying is passed through the napping machine 5 times to create ultra-fine fibers, and then buffed at a slow speed with coarse 100 mesh emery paper to raise the nap. Then, the binder adhering to the surface fibers was removed, and then finishing buffing was performed using fine 200 mesh emery paper. The resulting material sheet had a thickness of 0.8 mm;
Fineness 0.05 denier ~ 0.1 denier, length 0.3 mm ~ 4
It had a fluffy layer in which ultrafine fibers of mm in diameter were densely grown at a density of about 830,000 fibers/cm ² . A 20% solution of two-component urethane was applied to the fluffed surface of this material sheet using a 180 mesh gravure roll and dried to remove the solvent. Furthermore, coating and drying were repeated three times under the same conditions to provide about 12 g/m ² of polyurethane. As a result, a sheet was obtained that had a surface layer formed by mixing the two-component urethane resin and the tips of the fluff fibers, and an intermediate layer consisting mainly of the root portions of the fluffs. Next, a release paper was superimposed on the coated surface, and hot pressing was performed using a press roll set at 140° C., and after aging, the release paper was peeled off. After that, the cross section and surface of the product, which was dyed and coated with an embossing finishing agent, are shown in Figures 1 and 2. This material is a leather-like sheet material that feels comfortable in the hand and has a deep appearance similar to natural leather, and has good durability and scratch resistance.It is also suitable for processing and sewing as a material for clothing. It was excellent.

Comparative Example The substrate after slicing in Example 1 was only buffed using 250 mesh emery paper. The surface of the material sheet obtained was substantially fluff-free and had good smoothness. This material sheet was subjected to the same treatment as in Example 1 to obtain a sheet-like product. The obtained sheet-like material had many defects compared to that obtained in Example 1, such as having a harder texture, bending at an acute angle when folded, and being prone to cracking when stretched.

Example 2 The base material finished with 200 mesh emery paper in Example 1 was dyed at a high temperature of 130° C. using a disperse dye using a jet dyeing machine. The resulting material sheet had better fluff separation than the sheet before dyeing and had a polyurethane feel. After lightly brushing to smooth out the fluff, a composite layer of fluff fibers and two-component urethane was formed on the fluffed surface of this base material in the same manner as in Example 1. As a result, a sheet was obtained that had a surface layer formed by mixing the tips of the fluff fibers and polyurethane, and an intermediate layer consisting of the base of the fluff. The material that was then embossed and coated with a finishing agent had good drapability, a deep color, and a leather-like sheet with good scratch resistance, making it suitable as a material for clothing.

Example 3 The fluffed surface of the material sheet that was dyed at high temperature using a jet dyeing machine in Example 2 and lightly brushed was coated with 20 g of a 30% solution of saturated thermoplastic polyester resin (melting point = 130°C) on a siliconized stainless steel support. /m ² , dry to remove the solvent, heat the stainless steel support to 140°C, melt the polyester resin, overlap it and pressurize it to insert the fibers in the fluff surface layer and the polyester resin. After assembling and cooling, the stainless steel support was peeled off. Thereafter, the embossed and finished product had a luster similar to that of natural leather, and was a leather-like sheet material with good durability and scratch resistance.

Example 4 150 of polyethylene terephthalate as warp
Using denier, 48 filament false twisted yarn,
No. 20 is a 3.8 denier, 51 mm piece of polymer mutual array fiber in a form in which one filament contains 36 ultrafine fibers, with the binding component being 20 parts polystyrene and the ultrafine fiber component being 80 parts polyethylene terephthalate as the weft. It was used as a double-spun yarn to make a 5-ply satin fabric. This was introduced into boiling water for shrinkage treatment, dried, and then thoroughly washed with trichlorethylene to extract and remove polystyrene.
After that, it was dyed with a disperse dye using a jet dyeing machine and dried. When this was passed through a napping machine 13 times for the napping process, approximately 350,000 ultrafine fibers/cm ² were produced with a thickness of 0.57mm, a fineness of 0.08 to 0.12 denier, and a length of 0.5 to 3mm.
A raised fabric was obtained having a fluff layer generated at a density of . The napped side of this napped fabric was subjected to the same treatment as was suitable for the material sheet finished with 200 mesh emery paper in Example 1, except for dyeing. The resulting product had a supple feel, was resistant to scratches, and had particularly good drapability, making it useful for women's dresses and coats.

[Brief explanation of drawings]

FIGS. 1 and 2 are micrographs of the cross section and surface of the leather-like sheet material of the present invention. 1 is a surface layer formed by mixing the tips of fluff fibers and a non-porous elastomer, 2 is an intermediate layer consisting of the roots of fluff fibers, and 3 is a base layer. FIGS. 3 and 4 are micrographs of the cross section and surface of an example of a material sheet used in the present invention. 4 indicates fluff fibers.

Claims (1)

[Claims] 1 A surface layer formed by mixing a non-porous elastomer with the tips of fluff fibers having a diameter of 0.5 denier or less, and a base layer of the fluff fibers that exists adjacent to the surface layer and consists essentially of the elastomer. 1. A leather-like sheet-like material having an intermediate layer not present on at least one side of a base layer.