JPWO2015059924A1 - Synthetic leather and method for producing the same - Google Patents

Abstract

Provided is a synthetic leather having excellent wear resistance that is optimal for industrial materials such as vehicle interior materials and interior materials, in particular, seat seats, and having no problem of whitening. On one surface of the synthetic leather fibrous base material, a skin layer made of polyurethane resin and a surface treatment layer containing polyurethane resin and a silicone compound are sequentially laminated, and the silicone compound is a solid silicone resin A synthetic leather comprising a compound and a silicone compound of low flowability liquid.

Description

  The present invention relates to a synthetic leather and a method for producing the same. Specifically, the present invention relates to synthetic leather suitable for industrial materials such as vehicle interior materials and interior materials.

  Synthetic leather is used in various fields such as clothing, bags, shoes, and industrial materials as a substitute for natural leather, or as a leather material with better durability than natural leather. Synthetic leather is generally formed by laminating a skin layer made of polyurethane resin on a fibrous base material (for example, non-woven fabric, woven fabric, knitted fabric, etc.).

  Synthetic leather used for industrial materials such as vehicle interior materials and interior materials is required to have excellent durability, particularly wear resistance. Various efforts have been made to meet these requirements.

  For example, Patent Document 1 discloses a method in which a skin layer is formed of a silicone-modified polycarbonate polyurethane resin as a method for improving wear resistance by lowering the coefficient of friction of a polyurethane resin layer that becomes a surface of a synthetic leather. ing. Patent Document 2 discloses a method for applying a finishing agent containing an aqueous polyurethane resin, a crosslinking agent, a silicone compound and a filler to the surface of leather.

  However, in the method using a silicone-modified polycarbonate polyurethane resin for the skin layer as in Patent Document 1, silicone does not exist on the surface of the synthetic leather. Therefore, there is a problem that the abrasion resistance of the synthetic leather is not sufficient.

  The silicone oil added to the polyurethane resin layer disclosed in Patent Document 2 is generally a relatively low molecular weight and liquid silicone oil. Such silicone oil imparts high wear resistance to the synthetic leather, but has a problem that the surface of the synthetic leather is whitened. This whitening phenomenon is different from the whitening that occurs when the surface is worn away, and the silicone oil oozes out of the polyurethane resin layer when it is repeatedly worn and then appears white. it is conceivable that. Even when it is possible to prevent the surface from being scraped off when it is repeatedly worn on the seating surface of the vehicle or interior, there is a problem that whitening occurs due to the seepage of silicone oil.

  In order to solve the above-mentioned problems, the present applicant sequentially laminates a skin layer made of a polyurethane resin and a surface treatment layer containing a polyurethane resin and a solid silicone compound on one surface of the fibrous base material. Japanese Patent Application No. 2013-177001, which has not been disclosed on the priority date of the present application, proposes to make synthetic leather. However, when only a solid silicone compound is used for the surface treatment layer, the whitening is eliminated, but the wear resistance is not yet sufficient.

Japanese Unexamined Patent Publication No. 09-031862 Japanese Unexamined Patent Publication No. 2007-314919

  It is an object of the present invention to provide a synthetic leather having excellent wear resistance that is optimal for industrial materials such as vehicle interior materials and interior materials, in particular, seat seats, and having no whitening problem. .

  The synthetic leather according to the embodiment of the present invention is formed by sequentially laminating a skin layer made of a polyurethane resin and a surface treatment layer containing a polyurethane resin and a silicone compound on one surface of a fibrous base material, The silicone compound comprises a solid silicone compound and a low fluidity liquid silicone compound.

  The synthetic leather manufacturing method according to the embodiment of the present invention includes a step of applying a skin layer resin liquid on a releasable substrate to form a skin layer made of a polyurethane resin, and a skin layer and a fibrous material. A step of laminating the base material, a step of peeling the releasable base material, and a surface treatment layer resin solution containing a polyurethane resin, a solid silicone compound and a low fluidity liquid silicone compound on the skin layer And a step of forming a surface treatment layer.

  ADVANTAGE OF THE INVENTION According to this invention, it can be set as the synthetic leather which has the outstanding abrasion resistance optimal for industrial materials, such as a vehicle interior material and interior material, and does not have the problem of whitening.

  The synthetic leather in this embodiment is formed by sequentially laminating a skin layer made of a polyurethane resin and a surface treatment layer containing a polyurethane resin and a silicone compound on one surface of a fibrous base material. The compound is composed of a solid silicone compound and a low fluid liquid silicone compound.

  Examples of the fibrous base material used in the present embodiment include fabrics such as woven fabrics, knitted fabrics, and nonwoven fabrics, and natural leather (including floor leather). In addition, the cloth is coated or impregnated with a known solvent-free, solvent-based or water-based polymer compound such as polyurethane resin or a copolymer thereof as a main component, and solidified by dry coagulation or wet coagulation. Can also be used. In the fabric, the material of the fiber is not particularly limited, and examples thereof include natural fiber, regenerated fiber, semi-synthetic fiber, and synthetic fiber, and two or more of these may be combined. Among these, from the viewpoint of strength, the fiber material is preferably a synthetic fiber, and more preferably a polyester fiber.

  The fibrous base material may be colored with a dye or a pigment. The dye and pigment used for coloring are not particularly limited.

  The synthetic leather of this embodiment has a skin layer made of polyurethane resin as a first resin layer on one side of such a fibrous base material, and a solid silicone compound and a low resin layer as a second resin layer. A surface treatment layer made of a polyurethane resin containing a fluid liquid silicone compound is laminated.

  The polyurethane resin used for forming the skin layer is not particularly limited, and examples thereof include a polyether polyurethane resin, a polyester polyurethane resin, and a polycarbonate polyurethane resin. These can be used alone or in combination of two or more. Of these, polycarbonate polyurethane resins are preferred from the viewpoints of wear resistance and light fastness. In addition, the form of the polyurethane resin can be used regardless of whether it is a solventless system, a hot melt system, a solvent system or an aqueous system, and further, regardless of whether it is a one-component type or a two-component curable type. It can be selected appropriately.

  For the polyurethane resin, if necessary, known additives such as urethanization catalyst, cross-linking agent, heat stabilizer, light stabilizer, thermoplastic resin, thermosetting resin, dye, pigment, moisture permeability improver, Water repellent, oil repellent, hollow foam, water absorbent, moisture absorbent, deodorant, antifoam, antifungal agent, antiseptic, pigment dispersant, antiblocking agent, hydrolysis inhibitor, leveling agent, etc. 1 type (s) or 2 or more types can be contained.

  The thickness of the skin layer is preferably 5 to 100 μm, and more preferably 20 to 50 μm. When the thickness of the skin layer is 5 μm or more, it becomes easy to form a uniform resin layer, preventing the skin layer from being partially lost, and sufficient wear resistance can be obtained. When the thickness is 100 μm or less, it is possible to prevent the texture from becoming coarse and hard.

  The above-described skin layer is laminated on one surface of the fibrous base material. When laminating the skin layer, it may be via an adhesive layer or directly. By interposing an adhesive layer between the fibrous base material and the skin layer, an excess of polyurethane resin constituting the skin layer to the fibrous base material may occur when the skin layer is directly laminated on the fibrous base material. It is possible to suppress the penetration and the formation of uneven holes in the skin layer. Therefore, it can have a natural leather-like feel and texture.

  The synthetic leather of the present embodiment has a solid silicone compound and a low fluidity liquid silicone as the second resin layer on the surface of the skin layer made of polyurethane resin laminated on one side of the fibrous base material. A surface treatment layer made of a polyurethane resin containing a compound is laminated. Thereby, the abrasion resistance of synthetic leather improves. The surface treatment layer is a generic term for a resin layer as an outermost layer that is formed on the surface of the skin layer and protects the skin layer, and is composed of at least one resin layer, but two or more layers having the same or different composition It can also be constituted by a resin layer.

  The polyurethane resin used for forming the surface treatment layer is not particularly limited, and examples thereof include a polyether-based polyurethane resin, a polyester-based polyurethane resin, and a polycarbonate-based polyurethane resin. Or it can be used in combination of two or more. Of these, polycarbonate-based polyurethane resins are preferred from the viewpoint of wear resistance and light fastness. Further, the form of the polyurethane resin can be used regardless of whether it is a solventless system, a hot melt system, a solvent system or an aqueous system, and further, regardless of whether it is a one-component type or a two-component curable type. You can choose.

  The surface treatment layer contains a solid silicone compound and a low fluidity liquid silicone compound. More specifically, a solid silicone compound present in a dispersed state as solid particles in the surface treatment layer and a low fluidity liquid silicone compound that is liquid but difficult to deform in the surface treatment layer are blended. To do. Thereby, when an external pressure is applied to the synthetic leather, the silicone compound does not ooze out on the surface of the synthetic leather, and the small particles of the silicone compound dispersed in the surface treatment layer are less likely to be deformed. Therefore, the film forming property is good, the wear resistance is sufficient, and whitening due to the silicone compound leaching is suppressed.

  In the present specification, “solid” refers to a state having no fluidity at room temperature. “Room temperature” refers to a range of 25 to 35 ° C. The term “low-fluidity liquid” means that the fluidity is low at room temperature but low in fluidity. Specifically, it is a liquid with high viscosity such as a slurry or chickenpox at room temperature. Say something. Furthermore, among the silicone-based compounds that have fluidity at room temperature, those having a relatively large number average molecular weight as described later have a high molecular weight, so even if they have fluidity, their fluidity is not high. Therefore, it corresponds to a silicone compound of a low fluidity liquid. In addition, as to whether or not it has fluidity at room temperature, for example, when using a silicone compound aqueous dispersion as in the examples described later, properties in a dry residue obtained by evaporating water as a solvent from the aqueous dispersion Can be evaluated.

  The blending ratio (mass ratio) of the solid silicone compound and the low fluid liquid silicone compound is such that the low fluid liquid silicone compound is 0.3 to 4.0 with respect to the solid silicone compound 1. A range is preferable. By being in this range, film formability is good, excellent wear resistance can be exhibited, and whitening can be made difficult to occur. Furthermore, 0.5 to 2.5 is preferable.

  Examples of the silicone compound used in the present embodiment include dimethyl silicone (that is, polydimethylsiloxane), a modified product of dimethyl silicone, and a silicone / acrylic copolymer. Of these, dimethyl silicone is preferable from the viewpoint of versatility.

  Among the silicone compounds, the number average molecular weight of the solid silicone compound is preferably 400,000 to 700,000. That is, the solid silicone compound is preferably a silicone compound having a number average molecular weight of 400,000 to 700,000 that does not flow at room temperature. When the number average molecular weight is 400,000 or more, whitening can be made difficult to occur, and when the number average molecular weight is 700,000 or less, sufficient wear resistance can be exhibited. The number average molecular weight of the solid silicone compound is more preferably 550,000 to 700,000. In this specification, the number average molecular weight is a polyethylene glycol equivalent number average molecular weight (Mn) measured by a gel permeation chromatography (GPC) method.

  Further, the number average molecular weight of the low fluidity silicone compound is preferably 200,000 to 500,000. That is, the low fluidity liquid silicone compound is preferably a silicone compound having a fluidity at room temperature and a number average molecular weight of 200,000 to 500,000. When the number average molecular weight is 200,000 or more, whitening can be made difficult to occur, and when the number average molecular weight is 500,000 or less, a good tactile feel of the synthetic leather can be maintained. The number average molecular weight of the silicone compound of the low fluidity liquid is more preferably 250,000 to 450,000.

  In a preferred embodiment, as the silicone compound used for the surface treatment layer, the solid silicone compound is dimethyl silicone having a number average molecular weight of 550,000 to 700,000, and the low fluid liquid silicone compound is a number average molecular weight of 200,000 to 500,000 (more preferably 250,000-450,000) dimethyl silicone may be used.

  It is preferable that content (solid content) of the silicone type compound in a surface treatment layer is 5-33 mass% with respect to solid content of the polyurethane resin of a surface treatment layer, More preferably, it is 10-24 mass%, Furthermore, 14 to 33 mass% may be sufficient and 18 to 24 mass% may be sufficient. When the content of the silicone compound is 5% by mass or more, sufficient wear resistance can be exhibited. When the content of the silicone compound is 33% by mass or less, it is possible to maintain a good feel of the synthetic leather and to prevent whitening.

  The content (solid content) of the solid silicone compound in the surface treatment layer is preferably 9 to 18% by mass, and 12 to 15% by mass with respect to the solid content of the polyurethane resin in the surface treatment layer. More preferred. When the content of the solid silicone compound is 9% by mass or more, sufficient wear resistance can be exhibited. When the content of the solid silicone compound is 18% by mass or less, the film formability is good and sufficient wear resistance can be exhibited.

  It is preferable that content (solid content) of the silicone compound of the low fluidity liquid in a surface treatment layer is 5-18 mass% with respect to solid content of the polyurethane resin of a surface treatment layer, More preferably, it is 5-15. It is mass%, More preferably, it is 6-10 mass%. When the content of the silicone compound of the low fluidity liquid is 5% by mass or more, sufficient wear resistance can be exhibited. When the content of the silicone compound of the low fluidity liquid is 18% by mass or less, whitening can be hardly caused. Here, for the sake of convenience, the solid content of the low-fluidity liquid silicone compound is obtained by removing the low-fluidity liquid silicone compound (in the case of the examples described later, an aqueous silicone compound aqueous dispersion) at 130 ° C. This is based on the mass of the dry residue obtained by drying for 4 hours.

  The polyurethane resin of the surface treatment layer, if necessary, other than the above-mentioned silicone compounds, urethanization catalyst, silane coupling agent, filling, as long as the effects of the present invention are not impaired and the properties of the polyurethane resin are not impaired. Agent, thixotropic agent, tackifier, wax, heat stabilizer, light resistance stabilizer, fluorescent brightener, foaming agent, thermoplastic resin, thermosetting resin, dye, pigment, flame retardant, conductivity enhancer, charging Inhibitor, moisture permeability improver, water repellent, oil repellent, hollow foam, crystal water-containing compound, water absorbent, moisture absorbent, deodorant, foam stabilizer, antifoam, antifungal agent, antiseptic, antibacterial One kind of optional components such as algae, pigment dispersant, inert gas, anti-blocking agent, anti-hydrolysis agent, matting agent, feel improver, slip improver, cross-linking agent, thickener and leveling agent Or in combination of two or more .

  The thickness of the surface treatment layer is preferably 3 to 30 μm, and more preferably 5 to 15 μm. When the thickness is 3 μm or more, a uniform resin layer can be easily formed, and the surface treatment layer is prevented from being partially lost, and sufficient wear resistance is obtained. When the thickness is 30 μm or less, it is possible to avoid the possibility that the texture becomes coarse or whitening occurs.

  Next, the manufacturing method of the synthetic leather which concerns on this embodiment is demonstrated.

The manufacturing method according to the present embodiment includes the following steps.
(1) A step of applying a skin layer resin liquid on a releasable substrate to form a skin layer made of a polyurethane resin,
(2) A step of bonding the skin layer and the fibrous base material,
(3) a step of peeling the releasable substrate, and
(4) A step of applying a surface treatment layer resin liquid containing a polyurethane resin, a solid silicone compound and a low fluidity liquid silicone compound on the skin layer to form a surface treatment layer.

  As a method for applying the skin layer resin solution on the releasable substrate, various conventionally known methods can be employed, and the method is not particularly limited. For example, the method using apparatuses, such as a reverse roll coater, a spray coater, a roll coater, a knife coater, or a comma coater, can be mentioned. Among these, application with a reverse roll coater, knife coater, or comma coater is preferable in that a uniform thin film layer can be formed.

  The releasable base material used in the present embodiment is not particularly limited as long as it is a base material having releasability with respect to the polyurethane resin or a base material subjected to a release treatment. For example, release paper, release treated cloth, water repellent treated cloth, olefin sheet or film made of polyethylene resin or polypropylene resin, fluororesin sheet or film, plastic film with release paper, and the like can be mentioned. The releasable base material may have a concavo-convex pattern, and by using such a releasable base material, design properties can be imparted to the surface of the synthetic leather.

  What is necessary is just to set suitably the application | coating thickness of the resin liquid for skin layers according to the thickness of the said skin layer. The coating thickness is preferably 20 to 250 μm, and more preferably 100 to 200 μm. By setting the coating thickness within this range, a skin layer having a thickness of preferably 5 to 100 μm, more preferably 20 to 50 μm is obtained.

  After apply | coating the resin liquid for skin layers to a mold release base material, it heat-processes as needed. The heat treatment is performed to evaporate the solvent in the skin layer resin liquid and dry the resin. Further, when a cross-linking agent that causes a cross-linking reaction by heat treatment or when using a two-component curable resin, the reaction is promoted to form a film having sufficient strength.

  It is preferable that the heat processing temperature is 50-150 degreeC, More preferably, it is 60-130 degreeC. When the heat treatment temperature is 50 ° C. or higher, the heat treatment can be performed in a short time, the increase in process load can be suppressed, and the resin can be sufficiently crosslinked to improve the wear resistance. When the heat treatment temperature is 150 ° C. or lower, the texture of the synthetic leather is prevented from becoming coarse and hard. The heat treatment time is preferably 2 to 20 minutes, more preferably 2 to 10 minutes. When the heat treatment time is 2 minutes or longer, the resin is sufficiently cross-linked and the wear resistance can be improved. When the heat treatment time is 20 minutes or less, the processing speed is not slowed down, and the increase in process load is suppressed.

  Next, the skin layer and the fibrous base material are bonded together. It may be through an adhesive layer or may be laminated directly. Through the adhesive layer, excessive penetration of the polyurethane resin constituting the skin layer into the fibrous base material, which may occur when the skin layer is directly laminated on the fibrous base material, or unevenness in the skin layer As a result, natural leather-like feel and texture can be provided.

  A polyurethane resin is preferably used as the adhesive. Resins similar to those used for the skin layer can be used.

  The method for applying the adhesive may be any of various known methods and is not particularly limited. Examples thereof include a method using a device such as a reverse roll coater, a spray coater, a roll coater, a gravure coater, a kiss roll coater, a knife coater, or a comma coater.

  Next, the releasable substrate is peeled from the skin layer. By peeling, a laminate of the skin layer and the fibrous base material is obtained.

  Thereafter, a surface treatment layer is formed on the skin layer. As a method of applying the surface treatment layer resin liquid to the skin layer in order to form the surface treatment layer, various conventionally known methods can be employed and are not particularly limited. Examples thereof include a method using a device such as a reverse roll coater, a spray coater, a roll coater, a gravure coater, a kiss roll coater, a knife coater, or a comma coater. Especially, the application | coating by a reverse roll coater, a knife coater, or a comma coater is preferable at the point that formation of a uniform thin film layer is possible. What is necessary is just to set the application | coating thickness of a resin composition suitably according to the thickness of the said surface treatment layer.

  Next, heat treatment is performed as necessary. The heat treatment is performed to evaporate the solvent in the resin liquid for the surface treatment layer and dry the resin. Further, when a cross-linking agent that causes a cross-linking reaction by heat treatment or when using a two-component curable resin, the reaction is promoted to form a film having sufficient strength.

  It is preferable that the heat processing temperature is 50-150 degreeC, More preferably, it is 60-120 degreeC. When the heat treatment temperature is 50 ° C. or higher, the heat treatment can be performed in a short time, the increase in process load can be suppressed, and the resin can be sufficiently crosslinked to improve the wear resistance. When the heat treatment temperature is 150 ° C. or lower, the texture of the synthetic leather is prevented from becoming coarse and hard. The heat treatment time is preferably 2 to 20 minutes, more preferably 2 to 10 minutes. When the heat treatment time is 2 minutes or longer, the resin is sufficiently cross-linked and the wear resistance can be improved. When the heat treatment time is 20 minutes or less, the processing speed is not slowed down and the process load is prevented from increasing.

  Thus, the synthetic leather according to this embodiment is obtained. However, the method for producing the synthetic leather according to the present embodiment is not limited to the above method.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example. “Parts” in the examples are based on mass. Moreover, the following methods evaluated the obtained synthetic leather.

[Evaluation item]
[Whitening resistance]
This test was carried out by a robot equipped with a buttocks model that reproduces human movement (vertical movement, forward / backward movement, and twisting movement) on the seat.
Specifically, a test piece is placed on the buttock model under the conditions of temperature 20 ± 2 ° C. and humidity 65 ± 5% RH, the load is 77 kg weight (754.6 N), and the buttock model moves up and down (50 mm). Further, the wear and tear was repeated 250,000 times in this order by the back and forth motion (30 mm) and the twist motion (15 degrees). The test piece after abrasion was visually confirmed and judged according to the following criteria.
○: No change is observed on the surface Δ: Some whitening phenomenon is observed but not noticeable ×: Clear whitening phenomenon is observed

[Abrasion resistance]
A test piece with a width of 70 mm and a length of 300 mm was taken from each of the vertical and horizontal directions, and a urethane foam with a width of 70 mm, a length of 300 mm, and a thickness of 10 mm was attached to the back surface, and a flat surface wear tester It fixed to T-TYPE (made by Daiei Kagaku Seiki Seisakusho Co., Ltd.). A test piece was worn by applying a load of 9.8 N to a friction element covered with cotton cloth (cotton canvas). The frictional wear was 20,000 times of reciprocating wear at a speed of 60 reciprocations / minute between 140 mm on the surface of the test piece. At that time, the cotton canvas was replaced every 2500 reciprocations of wear, and a total of 20000 reciprocations were worn. The test piece after abrasion was observed and judged according to the following criteria.
5: No cracks, shavings and tears in the skin layer 4: Some cracks occurred in the skin layer 3: Cracks occurred in the skin layer 2: Cracks in the skin layer and shavings or tears occurred 1: Skin layer Is missing and the fibrous base material is visible

[Example 1]
(Formation of the skin layer)
To 100 parts by mass of a polycarbonate-based polyurethane resin (trade name “Chrisbon NY-328”, manufactured by DIC Corporation), 40 parts by mass of dimethylformamide is added, and the viscosity is adjusted to about 2000 mPa · s to obtain a polyurethane resin solution for the skin layer. Produced. The polyurethane resin solution was coated on a release paper with a comma coater so as to have a coating thickness of 200 μm, and then dried at 130 ° C. for 2 minutes to obtain a skin layer made of polyurethane resin.

(Formation of laminate)
50 parts by mass of dimethylformamide is added to 100 parts by mass of a polycarbonate-based polyurethane adhesive (trade name “Chrisbon TA-205”, manufactured by DIC Corporation), and the viscosity is adjusted to about 4500 mPa · s to obtain a resin solution for an adhesive layer. Produced. The resin solution was coated on the above-mentioned skin layer with a comma coater so as to have a coating thickness of 200 μm, and then dried at 100 ° C. for 1 minute.
The surface of the adhesive layer and the tricot knitted fabric are combined and press-bonded under 39.2 kPa for 1 minute, and then the release substrate is peeled off to obtain a laminate having a skin layer made of polyurethane resin having a thickness of 40 μm. It was.

(Formation of surface treatment layer)
The surface treatment layer polyurethane resin solution prepared according to the following prescription 1 is coated on the surface of the above skin layer with a river scooter, and then dried at 130 ° C. for 2 minutes to form a surface treatment layer having a thickness of 15 μm. The synthetic leather which concerns on an Example was obtained. In addition, the viscosity of the polyurethane resin liquid for the surface treatment layer was 3200 mPa · s (B-type viscometer, rotor: No. 4, 60 rpm, 23 ° C.).

Formula 1 (Polyurethane resin solution for surface treatment layer)
Water-based polycarbonate-based polyurethane resin (UC-02, manufactured by LANXESS Corporation, solid content 20% by mass): 100 parts by mass Isocyanate-based crosslinking agent (AQUADERM XL-50, manufactured by LANXESS Co., Ltd., solid content 40% by mass): 3 parts by mass Silicone compound aqueous dispersion 1 (dimethylsilicone (number average molecular weight 560,000, solid), solid content 60% by mass): 4 parts by mass Silicone compound aqueous dispersion 2 (dimethylsilicone (number average molecular weight 400,000, low fluidity) Liquid), solid content (content of dry residue) 30% by mass): 4 parts by mass Leveling agent (nonionic surfactant, AQUADERM Fluid H, manufactured by LANXESS, solid content 100% by mass): 1 part by mass

  As a result of evaluating the obtained synthetic leather, both the whitening resistance and the wear resistance were evaluated well.

In other examples and comparative examples, synthetic leather was produced in the same manner as in Example 1 except that the polyurethane resin composition for the surface treatment layer was produced according to Table 1. Details of the silicone-based compound aqueous dispersion 3 in Table 1 are as follows.
Silicone compound aqueous dispersion 3: dimethyl silicone (number average molecular weight 300,000, low fluidity liquid), solid content (content of dry residue) 30% by mass

  The evaluation of the synthetic leather produced by Examples and Comparative Examples was made by the method described above, and the results are shown in Table 1. As shown in Table 1, the synthetic leather of Comparative Example 1 containing only a solid silicone compound was inferior in abrasion resistance although it was excellent in whitening resistance. The synthetic leather of Comparative Example 2 containing only the low fluidity liquid silicone compound was inferior in whitening resistance although it was excellent in abrasion resistance. On the other hand, the synthetic leather of Examples 1 to 5 in which a solid silicone compound and a low fluidity liquid silicone compound were blended had excellent wear resistance and could suppress the whitening phenomenon. It was a thing.

Claims (4)

  On one surface of the fibrous base material, a skin layer composed of a polyurethane resin and a surface treatment layer containing a polyurethane resin and a silicone compound are sequentially laminated, and the silicone compound is a solid silicone compound and A synthetic leather comprising a low fluidity liquid silicone compound.   The compounding ratio of the solid silicone compound and the low fluid liquid silicone compound is 0.3 to 4.4 by mass ratio of the solid silicone compound 1 to the solid silicone compound 1. The synthetic leather according to claim 1, which is in the range of 0.   The synthetic leather according to claim 1 or 2, wherein the silicone compound of the low fluidity liquid is a silicone compound having a fluidity at room temperature and a number average molecular weight of 200,000 to 500,000. Applying a skin layer resin liquid on a releasable substrate to form a skin layer made of polyurethane resin;
Bonding the skin layer and the fibrous base material;
Removing the releasable substrate;
Applying a surface treatment layer resin liquid containing a polyurethane resin, a solid silicone compound and a low fluidity liquid silicone compound on the skin layer to form a surface treatment layer;
A method for producing synthetic leather, comprising: