JP3441253B2 - Artificial leather with a black grain surface layer with little stuffiness - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention suppresses a rise in the temperature of the inside and the back of artificial leather due to infrared rays by reflecting infrared rays on the front surface, thereby reducing stuffiness and flexibility. The present invention relates to artificial leather with a grain surface layer having a suitable elasticity and excellent form stability, and is particularly suitable for uses such as shoes, gloves, and clothing. [0002] Conventionally, artificial leather has been known for its flexibility, luxury,
Due to its easy-care properties, it is used in a wide range of applications such as sports shoes, clothing, gloves and the like. In addition, demands for diversification and functionality of products are increasing year by year, and unprecedented sensitivity and functionality are required. Among them, black or a color close to black is a color used in most applications, and particularly occupies a considerable weight in sports shoes and gloves. As the black pigment used for coloring the artificial leather with a blackish grain surface layer, carbon black has been mainly used so far in view of price, easiness of handling, and durability. But,
Conventional black-based artificial leather with carbon black using carbon black, because the surface absorbs infrared rays, when used as shoes or gloves, the temperature on the back surface increases during use, promoting sweating from the human body, Due to internal temperature rise and sweating,
It was the cause of my feet and hands coming off. In order to suppress the temperature rise, no countermeasure has been taken in the past. [0003] According to an aspect of the present invention comprises 2% or more black pigment that reflects infrared weight of the resin, 30
The resin layer composed mainly of polyurethane having a thickness of 100μm
Polycarbonate containing carbon black as upper layer and lower layer
The present invention relates to an artificial leather with a black grain surface layer , wherein a resin layer mainly composed of urethane is laminated. [0004] The artificial leather with a grain surface layer of the present invention is, for example,
It can be obtained by combining the following steps. That is, a step of producing an ultrafine fiber or a porous fiber-generating fiber that can be transformed into an ultrafine fiber bundle or a porous fiber, a step of producing an entangled nonwoven fabric made of the fiber, a step of temporarily fixing the nonwoven fabric, if necessary, A step of impregnating the synthetic nonwoven fabric with the elastic polymer liquid and wet-coagulating it, a step of transforming the fibers into ultrafine fiber bundles or porous fibers, and a step of laminating a resin containing a black pigment that reflects infrared rays on at least one surface. The above steps may be performed before the above steps, or the above steps may be performed after the above steps. In the present invention, a fiber obtained by removing a sea component from a fiber having a sea-island structure in a fiber cross section in a direction perpendicular to a fiber axis is an ultrafine fiber bundle, and a fiber obtained by removing an island component is also referred to as a fiber. It is called porous fiber. The fibers before the removal of the sea component are referred to as ultrafine fiber generating fibers, and the fibers before the removal of the island components are referred to as porous fiber generating fibers. The polymer constituting the island component of the microfiber-generating fiber of the present invention includes, for example, nylons represented by nylon 6, nylon 66, nylon 610 and nylon 12, other spinnable polyamides, Polyethylene terephthalate or a copolymer based on the same, polybutylene terephthalate or a copolymer based on the same, a spinnable polyester such as an aliphatic polyester or a copolymer thereof, polyethylene, polypropylene,
At least one polymer selected from melt-spinnable polymers such as polyolefins such as polybutylene, and the like. In addition, as a polymer constituting the sea component, a polymer having a small affinity with the island component is different from the island component in solubility or decomposability in a solvent or a decomposer.
And a polymer having a melt viscosity smaller than the melt viscosity of the island component polymer under spinning conditions or a polymer having a low surface tension, such as polyethylene, polypropylene, polystyrene, ethylene propylene copolymer, ethylene vinyl acetate. At least one polymer selected from polymers such as copolymers, styrene-ethylene copolymers, and styrene-acrylic copolymers can be used. As the polymer constituting the sea component and the island component of the porous fiber-generating fiber, the above-mentioned island component-forming polymer and sea component-forming polymer can be used, respectively, and the melt viscosity and surface tension of the sea component polymer and the island component polymer can be used. The relationship is the same as the relationship between the sea component polymer and the island component polymer. [0006] Additives such as a coloring agent and a deterioration inhibitor can be added to the polymer, if necessary. However, in the present invention, the properties are not affected by the balance with the surface color (for example, The addition of carbon black at 1 to 20% by weight (typically based on the polymer) further improves the quality of the product. The ratio of the ultrafine fiber component in the ultrafine fiber generating fiber or the ratio of the porous fiber component in the porous fiber generating fiber is preferably 40 to 80% by weight in view of spinning stability and economy. The microfine fiber-generating fiber and the porous fiber-generating fiber can be drawn to a fineness of about 2 to 10 by a conventionally known method through processing steps such as stretching, crimping, heat setting, cutting, and opening.
Denier fiber. [0008] The fineness of single fibers of the ultrafine fibers constituting the ultrafine fiber generating fibers is preferably 0.1 denier or less. If the single fiber fineness is 0.1 denier or more, the fibers are too thick and a soft texture cannot be obtained. However, it is possible to mix regular fibers within a range that does not impair the texture, and it is also possible to mix ultrafine fiber-generating fibers having different average fineness of the ultrafine fibers. The fibers constituting the artificial leather of the present invention, as described above, may be an ultrafine fiber bundle, or may be a porous fiber, preferably an ultrafine fiber bundle, in the case of an ultrafine fiber bundle In particular, the artificial leather has excellent flexibility. [0009] The ultrafine fiber-generating fiber or the porous fiber-generating fiber is defibrated with a card and forms a random web or a cross-wrap web through a webber. The obtained fiber web is laminated to a desired weight and thickness. . Subsequently, needle punching or water entanglement is performed by a known method to obtain an entangled nonwoven fabric. At this time, the above different fibers may be mixed. The number and conditions of the needle punches vary depending on the shape of the needle used and the thickness of the web, but are generally 200 to 2
It is set in the range of 500 punches / cm ² . If the needle punching conditions are too strong, the fiber cutting will increase rather than the fiber entanglement effect, resulting in a decrease in physical properties such as tear strength. If the needle punching conditions are too weak, physical properties such as peeling strength are reduced. This fiber-entangled non-woven fabric may be added with a step of temporarily fixing the non-woven fabric, if necessary, by gluing with a sizing agent such as polyvinyl alcohol or melting the sea component of the ultrafine fiber-generating fiber. Product properties,
The appearance can be improved. Next, the fiber entangled nonwoven fabric is impregnated with an elastic polymer and solidified. The elastic polymer impregnated into the fiber-entangled nonwoven fabric is, for example, at least one polymer selected from polyesterdiol, polyetherdiol, polycarbonatediol, etc. having an average molecular weight of 500 to 3000.
Diol and aromatic, alicyclic and aliphatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, isophorodiisocyanate and hexamethylene diisocyanate At least one selected from compounds
Species of diisocyanate compounds, ethylene glycol,
It is a polyurethane obtained by reacting at least one low-molecular compound having two or more active hydrogen atoms, such as ethylenediamine and butylene glycol, at a predetermined molar ratio. Polyurethane may be used as a polymer composition to which an elastic polymer such as synthetic rubber or polyester elastomer is added, if necessary. Next, a polymer liquid obtained by dissolving a polymer mainly composed of polyurethane in a solvent or dispersing in a dispersant is impregnated into a fiber-entangled nonwoven fabric, treated with a non-solvent of the polymer, and wet-coagulated. It is a fibrous substrate. If necessary, additives such as a coloring agent, a coagulation controlling agent, and an antioxidant are added to the polymer solution.In the present invention, carbon black is used in a range that does not affect the physical properties in consideration of the surface color. When a black pigment represented by is added, the quality of the product is further improved. In this case, a preferable addition amount of carbon black is
Due to the balance between blackness and physical properties, 0.1 to 5
% By weight. The amount of the polyurethane or polyurethane composition occupying the fibrous substrate is preferably in the range of 30 to 60% by weight as a solid content. When the ratio is out of this range, the balance between the fiber and the elastic polymer is deteriorated, and the product loses its stiffness and the swelling feeling cannot be obtained. The fibrous substrate impregnated with the polymer and coagulated is a non-solvent for the ultrafine or porous fibers and the polymer,
In addition, the ultrafine fiber-generating fiber is converted into an ultrafine fiber bundle or the porous fiber-generating fiber is treated as a porous fiber by treating with a solvent or a decomposing agent of the sea component of the ultrafine fiber-generating fiber or the island component of the porous fiber-generating fiber. This step may be performed prior to the polyurethane impregnation and coagulation steps described above. Further, when a paste such as polyvinyl alcohol is used in the temporary fixing step, the paste is removed by treating with a solvent (for example, water in the case of polyvinyl alcohol). Of course, this step may be performed later. Next, a resin containing a black pigment that reflects infrared rays is laminated on at least one surface of the substrate. The term “black pigment that reflects infrared light” as used in the present invention refers to a pigment obtained by kneading 2% by weight of the pigment with polyvinyl chloride in polyvinyl chloride and measuring it in a film having a thickness of 100 μm.
nm infrared reflectance (hereinafter referred to as infrared reflectance) is 7
It is a black pigment showing 0% or more. As the black pigment that reflects infrared rays, for example, perylene black (trade name: Paliogen Black: manufactured by BASF) is used. Examples of the resin to be laminated include polyester polyurethane, polyether polyurethane, polycarbonate polyurethane, and a mixture thereof.
A known resin such as a modified polyurethane resin such as silicon-modified polyurethane is used, and can be selected according to the application. If necessary, additives such as antioxidants and other coloring agents (pigments and dyes: need not be black, but may be red, dark blue, green, etc.) do not significantly impair the object of the present invention. You may add in the range. 100% of resin
The modulus can be selected according to the application.
From the viewpoint of surface feel, the range of 30 to 100 kg / cm ² is preferable. In the present invention, the ratio of the black pigment to the resin weight and the thickness of the resin layer to be laminated are selected as follows.
When the thickness is smaller than μm, it is difficult to conceal the color of the base layer, and in order to increase the concealment, the pigment ratio must be increased.
Increasing the pigment ratio leads to a decrease in physical properties and an increase in production cost. Preferably it is in the range of 30 to 100 μm. The thickness of the resin layer referred to herein is an average thickness. Further, the addition amount is required to be 2% or more, preferably 4 to 20% with respect to the resin weight in order to secure the infrared reflection effect. In terms of concealability and production cost, a more preferable embodiment in the present invention is to form a two-layer resin layer, use an infrared reflective pigment for the upper layer, and use ordinary carbon black for the lower layer (the layer closer to the base layer). It has a two-layer structure. The laminating method includes a coating method using a knife coat or a gravure coat, a method of applying a resin on a release paper, bonding the resin to a substrate, drying the resin, and then peeling the release paper.
A conventionally known method such as a method in which a molten resin is applied on a substrate and solidified by cooling is used. Also, prior to lamination, coloring, relaxing treatment to improve the texture, etc.
It is possible to pretreat the substrate. EXAMPLES The practice of the present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The parts and percentages in the examples relate to weight unless otherwise specified. Reference Example 1, Example 1, Comparative Example 1 2.5 parts of 10 denier mixed spun fiber comprising 50 parts of 6 nylon containing carbon black and 50 parts of polyethylene was used.
The fiber was stretched twice, crimped, and cut into a fiber length of 51 mm to obtain a staple. Next, a web is produced with a cross wrap webber, and alternately from both sides of the web, a total of 400 punches / c.
carried out of the needle punching m ^2, a basis weight of 500g / m
Fiber entangled nonwoven fabric No. ² was prepared. This non-woven fabric is made of polyethylene propylene glycol having an average molecular weight of 2,000,
Impregnated with a 16% dimethylformamide solution of polyurethane polymerized from 4,4'-diphenylmethane diisocyanate and ethylene glycol, coagulated, washed with water, and then dissolved and removed with polyethylene in toluene to a thickness of 1.3.
mm black sheet-like substrate was obtained. Of this sheet-like substrate,
The weight ratio of fiber to polyurethane was about 60:40. Next, a resin was applied to the release paper according to the formulation described in Table 2, and after bonding to the sheet-like substrate, drying was performed, the release paper was peeled off, and the resin layer was laminated on the sheet-like substrate. A leather-like sheet was obtained. Each of these sheets had moderate elasticity and flexibility, and was very similar to natural leather in appearance, texture and physical properties. [0020] From these sheets, cut a circular sample having a diameter of 10 cm, placed in the top tree fat layer, Part 1
Infrared rays were irradiated from above by 2.5 cm (5 inches) with an infrared lamp, and the temperature of the back surface of the sample was measured by a surface thermometer. Table 1 shows the relationship between the irradiation time and the temperature rise at this time. [ Table 1] As is clear from Table 1, Reference Example 1 and
Leather-like sheet of Example 1 is compared with Comparative Example 1, the temperature increase becomes very low. Furthermore Reference Example 1, to prepare a men's shoe with a leather-like sheet of Example 1 and Comparative Example 1 as each carapace, in the sunny day of July, in one of the legs Reference Example 1 or
Wear shoes with a leather-like sheet of Example 1, to wear shoes with a leather-like sheet of Comparative Example 1 on the other foot, as a result of the wear test by 4 people, in any of the wearer, The shoes using the leather-like sheet of Reference Example 1 and Example 1 showed little stuffiness, while the shoes using the leather-like sheet of Comparative Example 1 showed great stuffiness. [ Table 2] NY-333: Polycarbonate polyurethane resin (Dai Nippon Ink) 25% solids, 100% modulus = 65 kg
/ cm ² Paliogen Black L0084: Infrared reflective pigment (manufactured by BASF) Pigment content 1
00% Infrared reflectance 85% Dilac Black L1770S: carbon black pigment (manufactured by Dainippon Ink) Pigment content 20% Infrared reflectance 5% The artificial leather with black silver of the present invention turns black. Nevertheless, the temperature rise due to infrared rays was extremely low, which was equivalent to that of artificial leather with a white silver surface. Furthermore, it has moderate elasticity and flexibility, and is very similar to natural leather in texture, appearance and performance.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) D06N 3/14

Claims (1)

(57) [Claim 1] A resin layer mainly composed of polyurethane and having a thickness of 30 to 100 μm , containing 2% or more of a black pigment that reflects infrared rays with respect to the weight of the resin. The upper layer and the lower layer
Polyurethane-based resin containing bon black
Artificial leather with a black grain surface layer, characterized in that layers are laminated.