JP2608916B2 - Leather-like sheet and method for producing the same - Google Patents

Description

The present invention relates to a leather-like sheet having a sufficiently deep uneven surface pattern.

[Conventional technology]

Conventionally, as a method of forming a polyurethane-based polymer coating film having a unique mountain-shaped sufficiently deep uneven surface structure,
A polyurethane polymer solution is applied to a substrate such as a film, a nonwoven fabric, or a woven fabric, immersed in a coagulation bath, taken out while the coagulation of the polymer is not completed, and in a coagulation bath having a swelling effect on the polymer. It is possible to advance coagulation with
No. 583, also apply a polymer solution such as polyurethane on the surface of the fibrous base material, coagulate in a non-solvent of the polymer, when producing a sheet having a surface coating layer,
While the coagulation of the polymer is largely complete but still retains some fluidity, the polymer layer is embossed to provide a densified surface layer that is still moisture permeable. Japanese Patent Publication No. 50-26604 discloses that a high leather-like sheet can be obtained.
Japanese Patent Application Laid-Open No. 63-42979 proposes a method in which a synthetic resin layer is provided on a base of about 15%, and a wet and heat rubbing process is performed to give a rubbing.

[Problems to be solved by the invention]

In the production of conventional leather-like sheets, embossing patterning of the surface is performed at a temperature higher than a temperature sufficient to soften the polymer on the porous or non-porous surface layer of the polymer applied to the surface of the base layer. Embossing shaping with pressure.
For this reason, it is difficult to engrave an embossing roll having a deep uneven pattern or an embossing roll having a complicated pattern with deep unevenness, and also to maintain and manage the embossing roll so as not to damage the embossing roll. In addition, when a deep uneven pattern is to be clearly formed, not only a very high temperature and pressure are required but also special embossing is required to prevent the mold from returning. Furthermore, the texture of the embossed product is hardened, and the moisture permeability is significantly reduced. Also, artificially sculpted patterns become uniform and monotonous, making them unattractive from a product design perspective.

Therefore, based on the prior art, when trying to produce a sheet-like material having a surface layer having a sufficiently deep uneven surface wrinkle surface structure, when coagulated in a coagulation bath of a non-solvent of the polymer, during the coagulation is not completed In the method of taking out and coagulating in the coagulation bath of the polymer swelling agent, continuously changing the coagulation bath and selecting the bath composition of the coagulation bath of the swelling agent, the timing of moving the coagulation bath,
There are many manufacturing difficulties such as setting control of coagulation conditions and treatment of the swelling agent held in the sheet after coagulation, and further disadvantages such as reduced porosity of the porous surface layer and reduced moisture permeability. is there. On the other hand, in the method in which embossing is performed in the middle of solidification, selection of the time of solidification for embossing, removal of polymer debris, dirt, and the like that have entered concave portions of the embossing roll are frequent, complicated, and long. There are drawbacks such as difficulty in continuous production over time. Furthermore, even if it is rubbed while applying wet heat, a sufficiently deep uneven wrinkled structure cannot be obtained.

The present invention is a surface layer having a complex wrinkle structure having a sufficiently deep unevenness, having no artificial monotonous monotony, having a high moisture permeability, a soft feel, and a control of manufacturing conditions. An object of the present invention is to provide an easy method for producing a leather-like sheet.

[Means for solving the problem]

According to the present invention, a fibrous sheet having at least 10% area shrinkage or a fibrous sheet containing a polymer is used as a base layer, and a surface layer of a polymer mainly composed of an elastic polymer is provided on one surface of the base layer. And a leather-like sheet characterized in that the surface layer has deep uneven wrinkles without uniform monotony due to shrinkage of the substrate.

The present invention also provides a porous polymer layer or a non-porous polymer layer of a polymer mainly composed of an elastic polymer on one surface of a fiber sheet having at least 10% area shrinkage or a fiber sheet containing a polymer. Is formed, and then the fiber sheet is shrunk in the relaxing step or the preparation step in the dyeing step and / or the dyeing step, and deep uneven wrinkles are formed on the surface polymer layer without uniform monotony. This is a method for producing a leather-like sheet.

At least 10 constituting the substrate of the leather-like sheet of the present invention
% Is a fiber sheet made of fibers that exhibit shrinkage by heat treatment (dry heat or wet heat), chemical treatment, or a combination thereof. Fibers are fibers that exhibit shrinkage under spinning conditions (eg, spinning conditions in a high-speed spinning method), drawing conditions, denaturation of a fiber-forming polymer (copolymerization, addition of additives), and the like. For example, polyethylene terephthalate, copolymerization Polyester such as polyethylene terephthalate, polybutylene terephthalate, polyamide such as 6-nylon, 66-nylon, 610-nylon, 11-nylon, polyvinyl chloride, copolymerized polyvinyl chloride, polyethylene, polypropylene, copolymerized polyolefin, polyacrylonitrile or Weight selected from acrylonitrile copolymer, etc. To remove one component constituting a fiber from a single component fiber obtained by spinning a coalesced fiber or a multicomponent fiber obtained by spinning at least two kinds of polymers, or to separate and split a multicomponent fiber into components. Fibers that change the fiber form and exhibit shrinkage, such as polyester / polyolefin, polyester / polystyrene or copolymerized polystyrene, polyamide / polyolefin, polyurethane, polyolefin or copolymerized polyolefin, polyurethane / polystyrene or copolymerized polyolefin, polyester Elastomer /
Multi-component fibers such as polyolefins or copolymerized polyolefins. A fiber web is prepared by selecting one or two or more types of shrinkage-expressing fibers and blending sufficient shrinkage-expressing fibers and non-shrinkable fibers to shrink the fiber sheet alone or the fiber sheet by at least 10%. The above fiber web is laminated on one or both sides of a fiber entangled nonwoven fabric or a woven fabric obtained by a fiber entanglement treatment by needle punching and / or high pressure water jet treatment, and the fiber entanglement treatment is performed to entangle the fiber with the woven fabric. It is a laminated nonwoven fabric or a fiber woven knitted fabric in which a nonwoven fabric is integrated. The fiber sheet is shrunk by at least 10% in area by performing dry heat treatment or wet heat treatment, or preliminarily subjecting the fiber sheet to a chemical treatment and then heat treatment. Preferably, shrinkage is developed in the range of 17% to 60% in area. If the shrinkage is small, a sufficiently deep uneven wrinkle is not formed or the desired uneven wrinkle is formed without being able to withstand the stress of the surface coating polymer layer. On the other hand, if the expression of shrinkage is too large, not only the state where the deep uneven wrinkles are dense and the pattern does not exhibit a pattern form, but also the hardness of the surface layer is felt. Further, another method of expressing shrinkage of a fiber sheet is to remove one component constituting the multi-component fiber by using a chemical treatment or a combination of a chemical treatment and a heat treatment on a fiber sheet made using the multi-component fiber, or by using a multi-component range. Is separated and divided into fine fiber components, whereby the tension of at least one component constituting the multicomponent fiber is released and contracted. The fiber sheet may contain a polymer mainly composed of an elastic polymer as long as the shrinkage action is not impaired. Examples of the elastic polymer include a synthetic elastomeric polymer such as a polyurethane elastomer, a polyacrylate, a butadiene-acrylonitrile copolymer, a styrene-butadiene copolymer, a butadiene-acrylonitrile-styrene copolymer, and a polyester elastomer. And a natural rubber, polyvinyl chloride, a vinyl chloride copolymer, a polymer composition in which a polyallylonitrile, an acrylonitrile copolymer, and the like are blended.

The surface layer of the leather-like sheet of the present invention is a porous polymer layer or a non-porous polymer layer formed of a polymer mainly composed of an elastic polymer. That is, a solution or dispersion of a polymer mainly composed of an elastic polymer, and, if necessary, an additive selected from a coloring agent, a thickener, a lubricant, a flame retardant, a foaming agent, a water repellent, a crosslinking agent, and the like. Is applied to one surface of a fiber sheet. As a coating method, a conventional coating method such as a conventional roll coating method, a curtain flow coating method, a spray method, and a liquid surface contact method is used. The polymer liquid applied to the fiber sheet surface solidifies in the non-solvent of the polymer,
The polymer is solidified by a method such as solidification by removing the solvent or dispersant by heat. Alternatively, a polymer solution or dispersion is coated on a release support, and the polymer is coagulated by coagulation in a non-solvent of the polymer or coagulation by removing the solvent or dispersant by heat. A sheet comprising a fiber sheet and a surface polymer layer can be obtained by, for example, bonding a porous polymer film or a non-porous polymer film of a polymer obtained by solidifying to a fiber sheet.

The elastic polymer constituting the surface layer is a polyurethane elastomer obtained by reacting a polymer glycol, an organic diisocyanate, and a low molecular compound having two active hydrogen atoms,
Vinyl chloride polymer containing plasticizer, plasticized polyamide,
It is a mixed composition of a polyurethane elastomer and another polymer or a copolymerized polyurethane elastomer.

The leather-like sheet having a surface layer of the present invention capable of forming uneven wrinkles due to shrinkage of a substrate is a fiber such as a nonwoven fabric, a fabric obtained by laminating and integrating a knitted fabric and a nonwoven fabric, a fibrous knitted fabric, and a fibrous woolen fabric. A sheet comprising at least 10% area shrinkage made of shrinkable fibers or shrinkable fibers and non-shrinkable fibers sufficient for the fiber sheet to exhibit at least 10% area shrinkage by shrinkage treatment. Using a fiber sheet having a polymer sheet, or impregnating the fiber sheet with a solution or dispersion of a polymer mainly composed of an elastic polymer, and coagulating the polymer in a non-solvent or a liquid that disrupts dispersion, Using a fiber sheet containing a polymer by removing a solvent or a dispersant, a porous sheet obtained by transfer molding an elastic polymer film formed on a release support on one surface of the fiber sheet. Coalescing layer or A leather sheet with silver having a non-porous polymer layer. A solution or dispersion of a polymer mainly composed of an elastic polymer is applied to one surface of the fiber sheet, and solidified in a non-solvent of the polymer or in a liquid that disrupts dispersion, or the solvent or dispersant is removed by a drying method. To obtain a silvered leather-like sheet having a porous polymer layer or a non-porous polymer layer. The conditions such as heat treatment applied in the process of producing the silvered leather-like sheet are preferably performed under conditions where the fiber sheet shrinks less than 5%. When the leather-like sheet is produced under the condition that the fiber sheet shrinks by 5% or more, not only the desired deep uneven wrinkles are not formed in the post-treatment, but also undesirable irregular large wavy undulations are formed. In addition, a sheet having a uniform thickness cannot be obtained.

Next, a polymer solution or a dispersion containing a colorant is applied to the surface of the polymer layer, if necessary, to form a colored layer on the leather-like sheet with silver. Apply the gloss adjusting polymer composition solution or dispersion. After performing a surface finishing treatment such as applying an easily dyeable polymer solution or dispersion, the silvered leather-like sheet is treated with a relaxor in warm water or in a polymer swelling agent or in warm water containing a swelling agent. Shrink the fiber sheet by at least 10% area. Alternatively, the fiber sheet is shrunk simultaneously with the dyeing in a dyeing solution containing a dye, which is a preparation step for dyeing. In addition, for the fiber sheet, a multicomponent fiber that can be divided into ultrafine fibers by a hot water treatment in a relaxation process and a dyeing process, or a multicomponent fiber that can be shrunk together with the divided ultrafine fibers or ultrafine fibers, is used for shrinking and / or ultrafine fibers. It is also preferable to carry out.

In the present invention, the leather-like sheet in which the fiber sheet is shrunk and the surface polymer layer is formed with uneven wrinkles may be subjected to treatment of the uneven wrinkle convex surface as necessary.

That is, to treat the convex surface of the uneven wrinkle, a mirror surface,
A metal roll or metal plate finished to a smooth surface such as a matte surface or a leather-like pattern surface is used. Preferably, it is a metal roll or a metal plate that can be heated, but more preferably, it is heated to 50 ° C. or higher, so that the head of the projection does not soften or melt and flow, and then the state of the treated portion, for example, gloss Metal rolls, metal endless belts, plastic endless belts, and metal plates that can be processed by a heating-cooling method that can be cooled until the shaping state does not change. Then, the convex surface of the surface polymer layer is pressed at a temperature and / or pressure at which the polymer can be deformed and processed to give a gloss to the head of the convex portion, to smooth the surface, or to provide a pattern. I do. In addition, as a special surface finishing treatment, the convex surface of the polymer layer having uneven wrinkles is pressed against a heated smooth surface or a patterned surface, and pressed from the fiber sheet surface with a projection having a desired shape. An object of the present invention is to provide a leather-like sheet having a surface in which a smooth portion having no partially uneven wrinkles and a portion having deep uneven wrinkles are mixed.

The surface state of the leather-like sheet obtained here will be described with reference to the drawings. FIG. 1 is a schematic view showing a state of uneven wrinkles formed on a polymer layer after the shrinkage treatment of the present invention, wherein 1 is a wrinkle concave portion, and 2 is a wrinkle convex portion. FIG. 2 is a schematic view showing a state in which the head of the convex portion is smoothed by hot pressing with a smooth metal roll on the surface of the uneven wrinkle formed in the polymer layer after the shrinkage treatment of the present invention. Wrinkle concave part, wrinkle convex part,
Reference numeral 3 denotes a portion where the head of the convex portion is smoothed. FIG. 3 shows a smooth portion where the surface of the polymer layer of the present invention is brought into contact with a metal roll having a smooth surface and pressed from the back surface of the sheet-like material with a projection-like material to perform shrinkage treatment, thereby forming no deep uneven wrinkles on the polymer layer. FIG. 1 is a schematic diagram showing a surface state including a surface in which a portion having wrinkles with deep irregularities is formed, wherein 1 is a concave portion of a wrinkle, 2 is a convex portion of a wrinkle, and 4 is a smooth surface pressed and deformed to a smooth surface. Plane.

The convex portion of the polymer layer having a deep uneven wrinkle obtained in the present invention is further provided with a gloss adjustment to enhance the surface heterogeneity, application of a polymer containing a coloring agent, softening treatment, or fiber. A leather-like sheet product is obtained by performing a finishing treatment such as finishing the sheet surface into a fiber-napped surface or finishing a smoothened silver surface.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to specific examples. In the examples, parts and% relate to weight unless otherwise specified.

Example 1. High-shrinkage polyethylene terephthalate fiber having a shrinkage rate of 51% in hot water at 70 ° C obtained by high-speed spinning and non-shrinkable polyethylene terephthalate fiber having a shrinkage rate of about 3% in hot water at 70 ° C Was mixed at a predetermined ratio to prepare a cross wrap web, and entanglement treatment was performed alternately from both sides with a # 40 needle using a needle punch to obtain a nonwoven fabric having a basis weight of about 130 g / m ² .
Then applying a liquid amount to be 15 g / m ² as a polyurethane weight on a release paper a SakuTsuta polycarbonate-based polyurethane solution using a mixed diol obtained by mixing polycarbonate diol and polyoxyethylene diol in a proportion of 80 to 20, dry after, the solvent solution mainly composed of polyoxytetramethylene based two-ethyl acetate polyurethane coating a liquid amount to be 20 g / m ² as a polyurethane amount, after removing the majority of the solvent, the one surface of the nonwoven fabric Laminate and place in a room at about 30 ° C for about 24
It was left for a long time to cure. Thereafter, the release paper was peeled off, and leather-like sheets 1 to 4 having leather grain on the surface were obtained.

Next, the leather-like sheet was simultaneously dyed and shrunk at 130 ° C. using a disperse dye and a metal complex dye in a high-pressure winch. After dyeing, zoping, washing and drying were performed to obtain a dyed leather-like sheet. Table 1 shows the surface condition of the leather-like sheet.

The surface states of the leather-like sheets 2 to 4 were as shown in the schematic diagram of FIG. A polyurethane convex portion is pressed against a heating portion of an embossing device in which the leather-like sheets 2 to 4 are stretched between a heating drum and a cooling drum, and the heating portion temperature of the endless mirror metal belt is 160 ° C. and the cooling portion temperature is 70 ° C. After bonding and peeling off from the metal belt in the cooling section, As shown, the head (3) of the convex portion is smooth and glossy, and the concave portion (1) and the low convex portion (2) not subjected to mirror finishing are less glossy and have a two-color appearance. It was a leather-like sheet with a certain uneven pattern.

In addition, when the convex portion of the leather-like sheet was pressed against the heating portion of the embossing device, it was pressed and adhered from the back surface with a press roll having projections, and peeled off from the metal belt at the cooling portion, as shown in the schematic diagram of FIG. As described above, a part of the convex portion became a smooth glossy surface (4), and the leather-like sheet had a two-colored uneven pattern.

〔The invention's effect〕

The present invention resides in a method for producing a silver-coated leather-like sheet having a surface layer formed with wrinkles having deep irregularities which is difficult to artificially produce, and has a shape that cannot be expressed by heating embossing.
A deep wrinkle-like pattern can be obtained without causing a decrease in texture hardening, bending resistance, moisture permeability and the like as a leather-like sheet.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a surface state of a leather-like sheet in which a deep uneven wrinkle pattern is expressed on the surface of the present invention, and FIG. It is a figure showing the state where it was smoothed. FIG. 3 is a schematic view showing another surface state of the leather-like sheet of the present invention in which a wrinkle-like pattern with deep unevenness is developed on the surface.

Claims (2)

(57) [Claims] 1. A fiber sheet having at least 10% area shrinkage or a fiber sheet containing a polymer is used as a base layer, and a surface layer of a polymer mainly composed of an elastic polymer is provided on one surface of the base layer. A leather-like sheet, wherein the surface layer has deep uneven wrinkles without uniform monotony due to shrinkage of the substrate. 2. A porous polymer layer or a non-porous polymer layer of a polymer mainly composed of an elastic polymer, on one surface of a fiber sheet having at least 10% area shrinkage or a fiber sheet containing a polymer. Is formed, and then the fiber sheet is shrunk in the relaxing step or the preparation step in the dyeing step and / or the dyeing step, and deep uneven wrinkles are formed on the surface polymer layer without uniform monotony. Manufacturing method of leather-like sheet.