Synthetic leather

Abstract

The present invention provides a synthetic leather capable of suppressing the generation of wrinkles. The synthetic leather is a resin layer (20) laminated on a fabric (10), wherein the fabric (10) is a tricot warp knitted fabric with hairiness (12) knitted using front yarns, middle yarns and back yarns, wherein the tricot warp knitted fabric has a warp pile knitted structure knitted using the front yarns, a warp plain knitted structure or a warp pile knitted structure knitted using the middle yarns, and an inserted structure or a warp pile knitted structure knitted using the back yarns, and the hairiness (12) is formed by raising the sinking arc surface of the tricot warp knitted fabric.

Description

Technical Field

[0001] The present invention relates to a synthetic leather in which a resin layer is laminated on a fabric. Background Art

[0002] Synthetic leather used as interior materials such as automobile interior materials and seat covers requires processability and dimensional stability. Therefore, non-woven fabrics and fabrics with excellent processability and dimensional stability are suitable as the fabrics used as the base material of synthetic leather. However, since non-woven fabrics and fabrics have excellent dimensional stability and poor elasticity, when used for products with complex three-dimensional shapes, there are problems such as poor shape tracking and poor appearance. Therefore, in order to improve shape tracking, synthetic leather using knitted fabrics as the base material has attracted much attention.

[0003] For example, there is a synthetic leather (referring to patent document 1) having a polyurethane resin layer laminated on the surface of tricot warp knitted fabric (Japanese: knitting ground). In the synthetic leather of patent document 1, by using tricot warp knitted fabric for base material, the fixed load elongation is improved, and the followability of the product shape is good, and the appearance is good.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2010-111989 Summary of the invention

[0007] Problems to be solved by the invention

[0008] In the case of sewing synthetic leather into a complex three-dimensional shape for automobile interior use, "gathering sewing" is implemented in which one synthetic leather is shrunk while being sewn while putting together synthetic leathers of different lengths. In the gathering sewing, the greater the reduction rate of the synthetic leather to be gathered from the original size to the size after gathering (hereinafter referred to as "gathering rate"), the more rounded the three-dimensional shape it is processed into, but the phenomenon that the synthetic leather on the shrinking side is easily deformed and wrinkled occurs, which is the so-called gathering wrinkles. Therefore, the following characteristics are required for synthetic leather used for automobile interior use: it can be sewn into a three-dimensional shape by gathering sewing with a large gathering rate, and it is not easy to generate gathering wrinkles.

[0009] However, due to the gathering of folds (Japanese: いせ The reason for wrinkles is that the deformation is accompanied by shrinkage, so it is difficult to suppress the occurrence of wrinkles simply by increasing the elongation. The synthetic leather of Patent Document 1 achieves high shape-following properties by increasing the elongation, but does not take into account the gathering of wrinkles.

[0010] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a synthetic leather capable of suppressing the generation of gathering wrinkles.

[0011] Means for solving problems

[0012] The characteristic structure of the synthetic leather of the present invention for solving the above-mentioned problems is as follows:

[0013] It is a synthetic leather with a resin layer laminated on fabric.

[0014] The above-mentioned fabric is a tricot warp knitted fabric with hairiness woven by front yarn, middle yarn and back yarn.

[0015] The tricot warp knitted fabric comprises: a warp pile knitted structure knitted with the front yarn, a warp plain knitted structure or a warp pile knitted structure knitted with the intermediate yarn, and an insertion structure or a warp pile knitted structure knitted with the back yarn.

[0016] The hairiness is formed by raising the sinker loop surface of the tricot knitted fabric.

[0017] According to the synthetic leather of this structure, the fabric is a tricot warp knitted fabric with hairiness woven by front yarn, middle yarn and back yarn, the tricot warp knitted fabric has a warp pile knitted structure woven by front yarn, a warp plain knitted structure or a warp pile knitted structure woven by middle yarn, and an insert structure or a warp pile knitted structure woven by back yarn, and the hairiness is formed by raising the sinking arc surface of the tricot warp knitted fabric, thereby the fabric has a moderate thickness and can absorb the deformation generated when the synthetic leather shrinks due to the gathering sewing by compressing and deforming in the thickness direction. As a result, the generation of gathering wrinkles in the synthetic leather can be suppressed.

[0018] In the synthetic leather of the present invention,

[0019] The thickness of the cloth is preferably 0.9 to 3.0 mm.

[0020] According to the synthetic leather of this structure, by making the cloth have the above-mentioned appropriate thickness, the deformation accompanying the gathering sewing is absorbed by the cloth, so the generation of gathering wrinkles can be suppressed. In addition, according to the synthetic leather of this structure, the texture of the synthetic leather is soft and good.

[0021] In the synthetic leather of the present invention,

[0022] The warp pile knitted structure knitted with the front yarn is preferably knitted in a manner that the number of needle back inlay yarns is 3 or more.

[0023] In the synthetic leather according to this configuration, the warp pile knitting structure knitted with the front yarn is knitted in such a way that the back-bar laying is three or more needles, so that the fiber ends of the front yarn fluff become longer, and thus the fabric has an appropriate thickness for absorbing the deformation associated with gathering sewing.

[0024] In the synthetic leather of the present invention,

[0025] The inserted structure knitted with the above-mentioned back yarn is preferably knitted in such a way that the back-bar laying is three or more needles.

[0026] In the synthetic leather according to this configuration, the inserted structure knitted with the back yarn is knitted in such a way that the back-bar laying is three or more needles, so that the fabric does not form loops based on the back yarn, and thus is lightweight. Also, due to the overlap of the sinker loops of the back yarn, the base fabric becomes thicker, and thus has an appropriate thickness for absorbing the deformation associated with gathering sewing.

[0027] In the synthetic leather of the present invention,

[0028] The plain knitting structure knitted with the above-mentioned middle yarn is preferably knitted in such a way that it becomes a closed loop.

[0029] In the synthetic leather according to this configuration, the plain knitting structure knitted with the middle yarn is knitted in such a way that it becomes a closed loop. Thus, since it is a plain knitting structure, the fabric becomes lightweight, and since it is a closed loop, the fabric is less likely to curl. In addition, since the plain knitting structure is a closed loop and the fabric is less likely to curl, the workability during the manufacture of the synthetic leather becomes good.

[0030] In the synthetic leather of the present invention,

[0031] The above-mentioned tricot warp knitted fabric preferably has the above-mentioned fiber ends of 650,000 to 8.5 million and 200,000 to 600,000 dtex (total decitex) per 25.4 mm × 25.4 mm.

[0032] Here, the total decitex refers to the sum of the decitex numbers of all the fiber ends per unit area. In the synthetic leather according to this configuration, by making the tricot warp knitted fabric have the above-mentioned appropriate number of roots and total decitex of fiber ends, the fiber ends are less likely to be flattened in the thickness direction during the lamination of the resin layer, and thus the fabric has an appropriate thickness for absorbing the deformation associated with gathering sewing.

[0033] In the synthetic leather of the present invention,

[0034] The fineness of the above-mentioned front yarn is preferably 44 to 250 dtex.

[0035] According to the synthetic leather of this configuration, since the fineness of the front yarn is within the above-mentioned appropriate range, the hairiness is less likely to be crushed in the thickness direction when the resin layer is stacked, so the fabric has an appropriate thickness to absorb the deformation associated with the gathering sewing.

[0036] In the synthetic leather of the present invention,

[0037] The fineness of the intermediate yarn and the rear yarn is preferably 30 to 220 dtex, respectively.

[0038] According to the synthetic leather of this configuration, by setting the fineness of the intermediate yarn and the back yarn to be within the above-mentioned appropriate range, the base fabric of the tricot fabric becomes thicker, so that the fabric has an appropriate thickness for absorbing the strain associated with the gathering sewing.

[0039] In the synthetic leather of the present invention,

[0040] The single yarn fineness of the front yarn is preferably 0.3 to 5.5 dtex.

[0041] According to the synthetic leather of this structure, by making the single yarn fineness of the front yarn in the above-mentioned appropriate range, the adhesion with the resin layer becomes good. In addition, when the resin layer is stacked, the hairiness is not easily flattened in the thickness direction, so the cloth has a more appropriate thickness.

[0042] In the synthetic leather of the present invention,

[0043] The single yarn fineness of the intermediate yarn and the rear yarn is preferably 0.3 to 5.5 dtex, respectively.

[0044] According to the synthetic leather of this configuration, since the single yarn fineness of the intermediate yarn and the back yarn are respectively within the above-mentioned appropriate ranges, the base knitted fabric of the tricot fabric becomes thicker, and thus the fabric has a more appropriate thickness.

[0045] In the synthetic leather of the present invention,

[0046] The sum of the 5% circular modulus in the course direction of the tricot knitted fabric and in the wale direction of the tricot knitted fabric is preferably 23 to 45 N / 25.4 mm.

[0047] According to the synthetic leather of this configuration, by making the sum of the course direction and the wale direction of the tricot fabric with a 5% circular modulus within the above-mentioned appropriate range, the synthetic leather has appropriate softness and the generation of gathering wrinkles can be further suppressed.

[0048] In the synthetic leather of the present invention,

[0049] The 5% circular modulus is preferably 9 to 30 N / 25.4 mm in the course direction of the tricot knitted fabric, and is preferably 10 to 22 N / 25.4 mm in the wale direction of the tricot knitted fabric.

[0050] According to the synthetic leather of this configuration, by setting the 5% circular modulus in the course direction of the tricot knit fabric and the wale direction of the tricot knit fabric to be within the above-mentioned appropriate ranges, gathering wrinkles are less likely to occur.

[0051] In the synthetic leather of the present invention,

[0052] The resin layer is laminated on the sinker arc side of the tricot fabric.

[0053] The thickness of the resin layer is preferably 100 to 280 μm.

[0054] Effects of the Invention

[0055] According to the synthetic leather of this structure, by laminating the resin layer on the sinker arc side of the tricot warp knitted fabric, the hairiness contacts the resin layer, so that the deformation of the resin layer accompanying the gathering sewing is absorbed by the compression deformation of the hairiness in the thickness direction, and the generation of gathering wrinkles can be suppressed. In addition, by setting the thickness of the resin layer to 100 to 280 μm, the deformation of the resin layer itself due to the gathering sewing can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 This is a cross-sectional image of the synthetic leather of the present invention.

[0057] Figure 2 This is a cross-sectional image of a fabric used for the synthetic leather of the present invention.

[0058] Figure 3 This is an image of the needle-knitted curved surface of the fabric used for the synthetic leather of the present invention.

[0059] Figure 4 This is a cross-sectional image of the vicinity of the resin layer of synthetic leather.

[0060] Figure 5 This is a diagram showing the knitting structure of tricot fabric used for the synthetic leathers of Examples and Comparative Examples.

[0061] Figure 6 This is a structural diagram of the knitting structure of the tricot fabric used for the synthetic leather of the example.

[0062] Description of Reference Numerals

[0063] 1: Synthetic leather

[0064] 10: Fabric (tricot warp knitting fabric)

[0065] 12: Fiber fuzz

[0066] 20: Resin layer Detailed implementation manner

[0067] Hereinafter, the synthetic leather of the present invention will be described. However, the present invention is not intended to be limited to the following configurations.

[0068] 〔Synthetic leather〕

[0069] Figure 1 It is a cross-sectional image of the synthetic leather 1 of the present invention. The synthetic leather 1 has a fabric 10 and a resin layer 20 laminated on the fabric 10. As described in the above problems, if the synthetic leather 1 is gathered and sewn into a complex three-dimensional shape, the greater the gathering rate, the easier it is to generate gathering wrinkles. The inventor thought of giving the synthetic leather 1 the property of being less likely to generate gathering wrinkles by studying the knitting structure (combination of knitting structures) of the fabric 10 that is the base fabric of the synthetic leather 1. As a result of in-depth research, it was found that by using a tricot warp knitting fabric with a specific structure for the fabric 10, the deformation generated when the synthetic leather 1 shrinks due to gathering sewing is absorbed by the compression deformation of the fabric 10 in the thickness direction, suppressing the generation of gathering wrinkles.

[0070] <Fabric>

[0071] Figure 2 It is a cross-sectional image of the fabric 10 used in the synthetic leather 1 of the present invention. Figure 3 It is an image of the stitch loop surface of the fabric 10. The fabric 10 is a tricot warp knitting fabric woven with a front yarn, an intermediate yarn, and a rear yarn, and has a base knitting fabric 11 and fiber fuzz 12. As the tricot warp knitting fabric used for the fabric 10, a warp knitting machine having one or more guide bars (Japanese: 筬) as the front guide bar, the middle guide bar, and the rear guide bar can be used for weaving. Here, the front guide bar, the middle guide bar, and the rear guide bar refer to the names given in order from the sinker loop surface S side of the woven fabric being woven toward the stitch loop surface N side among the plurality of guide bars arranged in the warp knitting machine. The yarns supplied from the front guide bar, the middle guide bar, and the rear guide bar to form the tricot warp knitting fabric are respectively called the front yarn, the intermediate yarn, and the rear yarn.

[0072] The thickness of the fabric 10 is preferably 0.9 to 3.0 mm, more preferably 1.0 to 1.8 mm. If the thickness of the fabric 10 is 0.9 to 3.0 mm, then in the thickness direction, the fabric 10 absorbs the deformation generated when the synthetic leather 1 shrinks due to gathering and sewing, thereby being able to suppress the generation of gathering wrinkles. In addition, the texture of the synthetic leather 1 becomes soft and good. When the thickness of the fabric 10 is less than 0.9 mm, it may not be possible to sufficiently suppress the generation of gathering wrinkles. When the thickness of the fabric 10 exceeds 3.0 mm, the texture of the synthetic leather 1 may be damaged.

[0073] The bottom fabric 11 is formed by a knitting structure knitted with the back yarn and a knitting structure knitted with the middle yarn.

[0074] The knitting structure knitted with the back yarn is an inserting structure or a warp plush knitting structure, and preferably an inserting structure. By making the knitting structure knitted with the back yarn the above-mentioned knitting structure, thus, through the overlapping of the sinker loops of the knitting structure knitted with the back yarn and the knitting structure knitted with the middle yarn, as shown in the image of Figure 3 , a high ridge (Japanese: 畝) is formed on the bottom fabric 11, and the fabric 10 has an appropriate thickness capable of absorbing the deformation associated with gathering and sewing. At this time, it is preferable that the back yarn is knitted in such a way that the back pad of the needle is 3 needles or more. If the back pad of the needle of the back yarn is 3 needles or more, the sinker loops formed by 3 or more back yarns overlap on one needle loop, and the bottom fabric 11 can be made thicker. In addition, if the knitting structure knitted with the back yarn is an inserting structure, no loops based on the back yarn are formed, so the fabric 10 becomes a lightweight fabric.

[0075] The knitting structure knitted with the middle yarn is a plain warp knitting structure or a warp plush knitting structure. By making the knitting structure knitted with the middle yarn the above-mentioned knitting structure, the fabric 10 is less likely to curl, and the workability during the manufacture of the synthetic leather 1 becomes good. In particular, when the knitting structure knitted with the back yarn is an inserting structure, the knitting structure knitted with the middle yarn is preferably a plain warp knitting structure. If the knitting structure knitted with the middle yarn is a plain warp knitting structure, the back yarn can be appropriately inserted to knit the inserting structure, and the back pad of the needle of the middle yarn itself becomes 1 needle, and a lightweight fabric 10 can be obtained. At this time, the plain warp knitting structure is preferably knitted through closed loops. If the plain warp knitting structure is a closed loop, the elongation of the fabric 10 in the wale direction of the tricot warp knitted fabric is suppressed, and it becomes less likely to curl.

[0076] The hairiness 12 is formed by raising the knitted structure knitted with the front yarn or the middle yarn by applying a raising treatment to the sinker camber S of the fabric 10. The knitted structure knitted with the front yarn is a warp pile knitted structure, and is particularly preferably a warp pile knitted structure knitted with more than 3 needles of the needle back padding. In the case where the hairiness 12 is formed by raising the front yarn, the knitted structure knitted with the front yarn is a warp pile knitted structure, so that the hairiness 12 becomes longer, and the fabric 10 has a moderate thickness. In addition, by making the needle back padding with more than 3 needles, the hairiness 12 formed with the front yarn becomes longer. The raising treatment applied to the sinker camber S is a half-cut raising treatment or a full-cut raising treatment, wherein the half-cut raising treatment is preferred. In the case of applying the full-cut raising treatment, in order not to reduce the strength of the fabric 10, it is necessary to apply the raising treatment to such an extent that the middle yarn and the back yarn are not raised.

[0077] The fabric 10 preferably has 65,000 to 850,000 hairiness 12 per 25.4 mm×25.4 mm and 200,000 to 600,000 dtex (total decimal points), and more preferably has 80,000 to 450,000 hairiness 12 per 25.4 mm×25.4 mm and 270,000 to 480,000 dtex (total decimal points). By having 65,000 to 850,000 hairiness 12 per 25.4 mm×25.4 mm and 200,000 to 600,000 dtex (total decimal points), the hairiness 12 is less likely to be crushed in the thickness direction when the resin layer 20 is laminated, so that the fabric 10 has an appropriate thickness that can absorb the deformation associated with the gathering sewing. When the number of hairiness 12 or the total decimal points is less than the lower limit, the hairiness 12 is crushed when the resin layer 20 is laminated, and the fabric 10 may become thin. When the number or total decibel of the hairy fibers 12 exceeds the upper limit, the mobility of the hairy fibers 12 decreases, and the deformation associated with the gathering sewing may not be absorbed in the fabric. For the number T of the hairy fibers 12 per 25.4 mm×25.4 mm, for example, when the raising treatment is a full-cut raising treatment, the front comb is one, and the needle removal arrangement of the front comb is "a" in "b" out, the number of filaments of the front yarn is f (roots), the coil row density of the tricot warp knitted fabric is d1 (coil row / 25.4 mm), and the coil wale density of the tricot warp knitted fabric is d2 (coil wale / 25.4 mm), the following formula (1) can be used:

[0078] T=f×d1×d2×2×{a / (a+b)}···(1)

[0079] Calculated. It should be noted that, when a plurality of guide bars are set as front bars, T is calculated for each front bar using the above formula (1), and these are summed up, thereby being able to calculate the number of hairiness 12 per 25.4 mm×25.4 mm. The total decitex is the sum of the decitex numbers of all hairiness 12 per unit area. Regarding the total decitex Dt of the hairiness 12 per 25.4 mm×25.4 mm, when the fineness of the yarn constituting the hairiness 12, such as the front yarn, is set to Df (dtex), the coil row density of the tricot warp knitted fabric is set to d1 (coil row / 25.4 mm), the coil longitudinal row density of the tricot warp knitted fabric is set to d2 (coil longitudinal row / 25.4 mm), and the fuzziness is set to R (%), it can be calculated by the following formula (2):

[0080] Dt=(Df×d1×d2×R) / 100···(2)

[0081] Figure it out.

[0082] The form of the front yarn, the intermediate yarn and the back yarn is not particularly limited, and they may be any of filament yarns or spun yarns. When using filament yarns, they may be twisted as needed, or the yarns may be given curling and bulkiness by applying false twisting, fluid disturbance (Taslan processing, interlacing processing, etc.). In particular, for the intermediate yarn and the back yarn, in order to make the fabric 10 have an appropriate thickness by forming the base knitted fabric 11 thicker, it is preferable to use yarns that have been given bulkiness.

[0083] For the fabric 10, by making the fineness of the front yarn, the intermediate yarn and the back yarn in an appropriate relationship, an appropriate thickness and knitting property can be obtained. For example, when the fineness of the front yarn is set to Df (dtex), the fineness of the intermediate yarn is set to Dm (dtex), and the fineness of the back yarn is set to Db (dtex), the following formula (3) is used:

[0084] Dr=Df / (Dm+Db)···(3)

[0085] The calculated fineness ratio Dr is preferably 0.5 to 2.5. When the fineness ratio Dr is 0.5 or more, the fabric 10 has an appropriate thickness, and when the fineness ratio Dr is 2.5 or less, the knitting property of the fabric 10 is good.

[0086] The fineness of the front yarn is preferably 44 to 250 dtex, more preferably 110 to 168 dtex. If the fineness of the front yarn is 44 to 250 dtex, the hairiness 12 is not easily crushed in the thickness direction when the resin layer 20 is stacked, so that the fabric 10 has an appropriate thickness that can absorb the deformation associated with the gathering sewing. When the fineness of the front yarn is less than 44 dtex, the hairiness 12 is crushed when the resin layer 20 is stacked, and the fabric 10 may become thinner. When the fineness of the front yarn exceeds 250 dtex, the mobility of the hairiness 12 becomes small, and the deformation associated with the gathering sewing may not be absorbed in the fabric 10.

[0087] The fineness of the intermediate yarn and the back yarn is preferably 30 to 220 dtex, more preferably 56 to 110 dtex. If the fineness of the intermediate yarn and the back yarn is 30 to 220 dtex, the base knitted fabric 11 becomes thicker, so that the fabric 10 has an appropriate thickness that can absorb the deformation associated with the gathering sewing, and the synthetic leather 1 has an appropriate strength. In the case where the fineness of the intermediate yarn and the back yarn is less than 30 dtex, the fabric 10 becomes thinner and is prone to gathering wrinkles, and the strength of the synthetic leather 1 is deteriorated. In the case where the fineness of the intermediate yarn and the back yarn exceeds 220 dtex, the elongation of the synthetic leather 1 is deteriorated and gathering wrinkles are easily generated.

[0088] The raw materials of the fibers (single fibers) constituting the front yarn, the middle yarn and the back yarn are not particularly limited, and examples thereof include natural fibers, regenerated fibers, semi-synthetic fibers, synthetic fibers, and the like. Among them, from the viewpoints of mechanical strength, heat resistance, and light resistance, synthetic fibers are preferred, and polyester fibers are more preferred. In addition, composite fibers composed of a combination of fibers of two or more raw materials may also be used. In addition, fibers imparted with functionality, such as flame retardancy, conductivity, deodorization, and the like, which are previously known functional fibers, may be used. For example, in the case of requiring high flame retardant properties, fibers imparted with flame retardancy may be used. The shape of the fiber is not particularly limited, and may be any of long fibers and short fibers. In addition, the cross-sectional shape of the fiber is not particularly limited, and may be a conventional circular shape, or may be a flat, elliptical, triangular, hollow, Y-shaped, T-shaped, U-shaped, and other special shapes.

[0089] The single yarn fineness of the front yarn is preferably 0.3 to 5.5 dtex, and more preferably 1.0 to 4.0 dtex. If the single yarn fineness of the front yarn is 0.3 to 5.5 dtex, the adhesion to the resin layer 20 is good. In addition, since the hairiness 12 is not easily crushed in the thickness direction when the resin layer 20 is stacked, the fabric 10 has an appropriate thickness that can absorb the deformation associated with the gathering sewing. In the case where the single yarn fineness of the front yarn is less than 0.3 dtex, the hairiness 12 is crushed when the resin layer 20 is stacked, and the fabric 10 may become thinner. In the case where the single yarn fineness of the front yarn exceeds 5.5 dtex, good adhesion to the resin layer 20 may not be obtained.

[0090] The single yarn fineness of the intermediate yarn and the back yarn is preferably 0.3 to 5.5 dtex, more preferably 1.0 to 4.0 dtex. If the single yarn fineness of the intermediate yarn and the back yarn is 0.3 to 5.5 dtex, the durability and texture of the synthetic leather 1 are good. In addition, by making the base knitted fabric 11 thicker, the fabric 10 has an appropriate thickness that can absorb the deformation associated with the gathering sewing. When the single yarn fineness of the intermediate yarn and the back yarn is less than 0.3 dtex, sufficient durability may not be obtained. When the single yarn fineness of the intermediate yarn and the back yarn exceeds 5.5 dtex, the texture may become hard.

[0091] <Resin layer>

[0092] Figure 4 2 is a cross-sectional image of the resin layer 20 of the synthetic leather 1. The resin layer 20 may be the same resin layer as that used in conventional synthetic leathers, and the type and layer structure of the resin are not particularly limited. As the resin constituting the resin layer 20, for example, polyurethane resin, vinyl chloride resin, etc. may be used. As the layer structure of the resin layer 20, for example, Figure 4In the cross-sectional image of , the resin layer 20 has a skin layer 21 including a resin sheet, and an adhesive layer 22 that bonds the skin layer 21 to the fabric 10. The thickness of the resin layer 20 is preferably 100 to 280 μm. It should be noted that, as the synthetic leather 1 as a whole, the thickness is preferably 1000 to 3280 μm by making the fabric 10 and the resin layer 20 have the above-mentioned preferred thicknesses respectively. If the thickness of the resin layer 20 is 100 to 280 μm, the deformation generated in the resin layer 20 becomes small when the synthetic leather 1 shrinks due to the gathering and sewing, so the deformation is easily absorbed in the fabric 10. In the case where the thickness of the resin layer 20 is less than 100 μm, the strength of the synthetic leather 1 may be deteriorated. In the case where the thickness of the resin layer 20 exceeds 280 μm, the deformation generated in the resin layer 20 becomes large when the synthetic leather 1 shrinks due to the gathering and sewing, so the deformation may not be absorbed in the fabric 10. The resin layer 20 is preferably laminated on the side of the sunken loop surface S of the fabric 10. As for the sunken loop surface S of the fabric 10, due to the influence of the ridges formed in the base knitted fabric 11, ridges W are also formed in the hairiness 12 (see Figure 1 Therefore, by laminating the resin layer 20 on the side of the sinking arc surface S, the fabric 10 and the resin layer 20 are bonded at the ridges W, and grooves G are formed between the ridges W (see Figure 1 ) As for the groove G, the yarns constituting the cloth 10 are easy to move, so even if a large deformation occurs due to the gathering sewing, the deformation can be absorbed in the cloth 10.

[0093] 〔5% circular modulus〕

[0094] The synthetic leather 1 of the present invention has the property of absorbing the deformation accompanying the gathering sewing by the compression deformation in the thickness direction of the fabric 10, and can further suppress the generation of gathering wrinkles by having appropriate softness. As an index of such softness, the synthetic leather 1 of the present invention preferably has a sum of the 5% circular modulus measured in the course direction of the tricot fabric and the 5% circular modulus measured in the wale direction of the tricot fabric of 23 to 45 N / 25.4 mm. By making the sum of the 5% circular modulus measured in the course direction and the 5% circular modulus measured in the wale direction within the above range, the synthetic leather 1 has appropriate softness and is less likely to generate gathering wrinkles. In addition, when the sum of the 5% circular modulus measured in the course direction and the 5% circular modulus measured in the wale direction is within the above range, the 5% circular modulus measured in the course direction is preferably 9 to 30 N / 25.4 mm, and the 5% circular modulus measured in the wale direction is preferably 10 to 22 N / 25.4 mm. When the 5% circular modulus measured in the course direction and the 5% circular modulus measured in the wale direction are respectively within the above ranges, gathering wrinkles are less likely to occur.

[0095] The determination of 5% circular modulus is carried out according to the following steps. First, two test pieces with a diameter of 300 mm are taken from synthetic leather 1. Under an atmosphere of room temperature 20±2°C and humidity 65±5% RH, the two test pieces are respectively oriented in the horizontal row direction and the vertical row direction of the coil, and are mounted on the clamp of a tensile testing machine Autograph AG-100A (manufactured by Shimadzu Corporation) with a clamping width of 25.4 mm without looseness. For the test piece, the test piece is stretched at a moving speed of the clamp of 200 mm / min, and the load (N / 25.4 mm) when the test piece is elongated by 5% is measured.

[0096] [Example]

[0097] The synthetic leathers of the present invention (Examples 1 to 6) were prepared and the formation of gathering wrinkles during gathering sewing was evaluated. In addition, for comparison, synthetic leathers outside the scope of the present invention (Comparative Examples 1 to 5) were prepared and similarly evaluated.

[0098] [Gather the folds]

[0099] From the synthetic leather, a test piece with a width of 50 mm and a length of 100 mm was taken from the course direction and the wale direction of the tricot fabric, and the test piece was sewn together in such a way that the length of the test piece was shortened to 97 mm. After sewing together, the test piece was visually checked for the presence of gathering wrinkles, and the evaluation was performed according to the following criteria.

[0100] ++: No wrinkles were generated.

[0101] +: Although wrinkles were slightly generated, it was not a problem in practical use.

[0102] -: Wrinkles are generated.

[0103] <Example 1>

[0104] A tricot machine (HKS3M: manufactured by MAYER Co., Ltd., Japan) with three guide bars was used. On the front guide bar, a 168 dtex / 48 f PET2H processed yarn was guided as the front yarn in a full-drawn manner to form a Figure 5 The warp pile knitting structure (3 needles and needle back pad yarn) shown in (a) is formed by guiding the 84dtex / 24f PET crimping yarn as the intermediate yarn in the middle combing bar in a full warp drawing manner. Figure 5 The closed loop warp plain weave shown in (b) is guided as the back yarn on the back comb bar by full warp drawing to form a PET curled yarn of 84dtex / 36f. Figure 5The inserted structure (3 needles and needle backing yarn) shown in (c) is used to knit a tricot warp knitted fabric. The obtained tricot warp knitted fabric is subjected to a half-cut raising treatment on the sinker loop surface to form hairiness by raising the front yarn, and is pre-set at 190°C for 1 minute, dyed and dried at 130°C, and post-set at 150°C for 1 minute.

[0105] 40 parts by mass of dimethylformamide were added to 100 parts by mass of a polycarbonate polyurethane resin (CRISVONNY-328: manufactured by DIC Corporation) to adjust the viscosity to about 2000 mPa·s to prepare a polyurethane resin liquid. The polyurethane resin liquid was applied to release paper to a coating thickness of 200 μm, and then dried at 130° C. for 2 minutes to obtain a polyurethane resin sheet serving as a skin layer.

[0106] 50 parts by mass of dimethylformamide were added to 100 parts by mass of a polycarbonate polyurethane adhesive (CRISVON TA-205: manufactured by DIC Corporation), and the adhesive resin solution having a viscosity adjusted to about 4500 mPa·s was applied to the polyurethane resin sheet formed above in a coating thickness of 200 μm, and then dried at 100°C for 1 minute to obtain an adhesive layer. The obtained adhesive layer was combined with the sinker arc surface of the tricot knitted fabric and bonded to the polyurethane resin sheet at 39.2 N / cm 2 The synthetic leather of Example 1 was obtained by pressing and crimping for 1 minute under the conditions. The thickness of the fabric in the synthetic leather of Example 1 was 1.35 mm, the thickness of the resin layer was 260 μm, and the thickness of the synthetic leather as a whole was 1610 μm. The 5% circular modulus of the synthetic leather of Example 1 was 10.30 N / 25.4 mm in the row direction, 15.32 N / 25.4 mm in the wale direction, and the sum of the row direction and the wale direction was 25.62 N / 25.4 mm.

[0107] <Example 2>

[0108] The intermediate yarn was changed to 84 dtex / 36f PET1H processed yarn, and the back yarn was changed to 84 dtex / 36f PET1H processed yarn. Except for this, the synthetic leather of Example 2 was obtained by the same conditions and steps as Example 1. The thickness of the fabric in the synthetic leather of Example 2 was 1.35 mm, the thickness of the resin layer was 220 μm, and the thickness of the synthetic leather as a whole was 1570 μm. The 5% circular modulus of the synthetic leather of Example 2 was 19.29 N / 25.4 mm in the row direction, 20.55 N / 25.4 mm in the wale direction, and the sum of the row direction and the wale direction was 39.84 N / 25.4 mm.

[0109] <Example 3>

[0110] The front yarn was changed to 110 dtex / 36f PET2H processed yarn. Except for this, the synthetic leather of Example 3 was obtained by the same conditions and steps as Example 1. The thickness of the fabric in the synthetic leather of Example 3 was 1.15 mm, the thickness of the resin layer was 130 μm, and the thickness of the synthetic leather as a whole was 1280 μm. The 5% circular modulus of the synthetic leather of Example 3 was 22.29 N / 25.4 mm in the row direction, 19.32 N / 25.4 mm in the wale direction, and the sum of the row direction and the wale direction was 41.61 N / 25.4 mm.

[0111] <Example 4>

[0112] The intermediate yarn was changed to 84 dtex / 36f PET2H processed yarn, and the back yarn was changed to 84 dtex / 36f PET2H processed yarn. The synthetic leather of Example 4 was obtained by the same conditions and steps as Example 1 except for the above. The thickness of the fabric in the synthetic leather of Example 4 was 1.24 mm, the thickness of the resin layer was 190 μm, and the thickness of the synthetic leather as a whole was 1430 μm. The 5% circular modulus of the synthetic leather of Example 4 was 17.98 N / 25.4 mm in the row direction, 17.94 N / 25.4 mm in the wale direction, and the sum of the row direction and the wale direction was 35.92 N / 25.4 mm.

[0113] <Example 5>

[0114] The front yarn was changed to 168dtex / 144f PET2H textured yarn, and the weaving structure based on the front yarn was changed to Figure 6 (a) shows a warp pile knitted structure (4 needles and needle back pad yarn). Otherwise, the synthetic leather of Example 5 was obtained by the same conditions and steps as Example 1. The thickness of the fabric in the synthetic leather of Example 5 was 1.52 mm, the thickness of the resin layer was 110 μm, and the thickness of the synthetic leather as a whole was 1630 μm. The 5% circular modulus of the synthetic leather of Example 5 was 28.32 N / 25.4 mm in the horizontal row direction, 13.54 N / 25.4 mm in the vertical row direction, and the sum of the horizontal row direction and the vertical row direction was 41.86 N / 25.4 mm.

[0115] <Example 6>

[0116] The front yarn was changed to 168dtex / 144f PET2H processed yarn, the back yarn was changed to 44dtex / 12f PET curling yarn, and the weaving structure based on the back yarn was changed to Figure 6(b) Warp pile knitted structure (2 needles and needle back pad yarn) shown. Except for this, the synthetic leather of Example 6 was obtained by the same conditions and steps as Example 1. The thickness of the fabric in the synthetic leather of Example 6 was 1.45 mm, the thickness of the resin layer was 200 μm, and the thickness of the synthetic leather as a whole was 1650 μm. The 5% circular modulus of the synthetic leather of Example 6 was 13.32 N / 25.4 mm in the horizontal row direction, 11.34 N / 25.4 mm in the vertical row direction, and the sum of the horizontal row direction and the vertical row direction was 24.66 N / 25.4 mm.

[0117] <Comparative Example 1>

[0118] The woven tricot fabric was not subjected to a raising treatment. Except for this, the synthetic leather of Comparative Example 1 was obtained by the same conditions and steps as Example 2. The thickness of the fabric in the synthetic leather of Comparative Example 1 was 0.93 mm, the thickness of the resin layer was 220 μm, and the thickness of the synthetic leather as a whole was 1150 μm. The 5% circular modulus of the synthetic leather of Comparative Example 1 was 26.32 N / 25.4 mm in the row direction, 19.32 N / 25.4 mm in the wale direction, and the sum of the row direction and the wale direction was 45.64 N / 25.4 mm.

[0119] <Comparative Example 2>

[0120] Change the weave structure based on the intermediate yarn to Figure 5 (d) The chain structure shown in the figure does not apply a raising treatment to the woven tricot warp knitted fabric. Otherwise, the synthetic leather of Comparative Example 2 was obtained by the same conditions and steps as in Example 1. The thickness of the fabric in the synthetic leather of Comparative Example 2 was 1.02 mm, the thickness of the resin layer was 190 μm, and the thickness of the synthetic leather as a whole was 1210 μm. The 5% circular modulus of the synthetic leather of Comparative Example 2 was 28.34 N / 25.4 mm in the horizontal row direction, 20.30 N / 25.4 mm in the vertical row direction, and the sum of the horizontal row direction and the vertical row direction was 48.64 N / 25.4 mm.

[0121] <Comparative Example 3>

[0122] Change the weave based on the back yarn to Figure 5(e) The closed loop warp plain knitted structure shown. Otherwise, the synthetic leather of Comparative Example 3 was obtained by the same conditions and steps as Example 1. The thickness of the fabric in the synthetic leather of Comparative Example 3 was 1.08 mm, the thickness of the resin layer was 180 μm, and the thickness of the synthetic leather as a whole was 1260 μm. The 5% circular modulus of the synthetic leather of Comparative Example 3 was 36.43 N / 25.4 mm in the row direction, 16.12 N / 25.4 mm in the wale direction, and the sum of the row direction and the wale direction was 52.55 N / 25.4 mm.

[0123] <Comparative Example 4>

[0124] The front yarn was changed to 84dtex / 24f PET crimp yarn, and the weaving structure based on the front yarn was changed to Figure 5 (b) shows a closed loop plain knitted structure, the intermediate yarn is changed to 168dtex / 48f PET crimping yarn, and the knitted structure based on the intermediate yarn is changed to Figure 5 (f) shows a warp pile knitted structure (4 needles and needle back pad yarn). In addition, by applying a half-cut raising treatment to the sinker arc surface of the tricot warp knitted fabric, hairiness that raises the intermediate yarn is formed. Otherwise, the synthetic leather of Comparative Example 4 is obtained by the same conditions and steps as Example 1. The thickness of the fabric in the synthetic leather of Comparative Example 4 is 1.17 mm, the thickness of the resin layer is 130 μm, and the thickness of the synthetic leather as a whole is 1300 μm. The 5% circular modulus of the synthetic leather of Comparative Example 4 is 32.73 N / 25.4 mm in the horizontal row direction of the coil, 17.21 N / 25.4 mm in the vertical row direction of the coil, and the sum of the horizontal row direction and the vertical row direction of the coil is 49.94 N / 25.4 mm.

[0125] <Comparative Example 5>

[0126] Change the weave based on the front yarn to Figure 5 The closed loop warp plain knitting structure shown in (b) is changed to the knitting structure based on the intermediate yarn Figure 5 (d) The chain structure shown. Otherwise, the synthetic leather of Comparative Example 5 was obtained according to the same conditions and procedures as in Example 1. The thickness of the fabric in the synthetic leather of Comparative Example 5 was 0.89 mm, the thickness of the resin layer was 180 μm, and the thickness of the synthetic leather as a whole was 1070 μm. The 5% circular modulus of the synthetic leather of Comparative Example 5 was 24.12 N / 25.4 mm in the row direction, 28.43 N / 25.4 mm in the longitudinal direction, and the sum of the row direction and longitudinal direction was 52.55 N / 25.4 mm.

[0127] The details and evaluation results of the synthetic leathers of Examples 1 to 6 are shown in Table 1 below, and the details and evaluation results of the synthetic leathers of Comparative Examples 1 to 5 are shown in Table 2 below.

[0128]

[0129] [Table 2]

[0130]

[0131] The synthetic leathers of Examples 1, 2, and 4 to 6 did not produce gathering wrinkles. The synthetic leather of Example 3 slightly produced gathering wrinkles, but the degree of wrinkles was suppressed to a small extent. In the synthetic leathers of Examples 1 to 4 and 6, the number of needle back padding yarns of the warp velvet knitted structure woven with the front yarn was 3 needles, and in the synthetic leather of Example 5, the number of needle back padding yarns was 4 needles. It can be considered that in order to suppress the occurrence of gathering wrinkles, it is preferred that the number of needle back padding yarns of the warp velvet knitted structure woven with the front yarn is 3 or more. In addition, in the synthetic leathers of Examples 1 to 5, the knitted structure woven with the back yarn is an insertion structure, and in the synthetic leather of Example 6, the knitted structure woven with the back yarn is a warp velvet knitted structure. It can be considered that in order to suppress the occurrence of gathering wrinkles, the knitted structure woven with the back yarn is preferably an insertion structure or a warp velvet knitted structure.

[0132] On the other hand, the synthetic leathers of Comparative Examples 1 to 5 all had gathered wrinkles. The combination of the knitting structure of the tricot warp knitted fabric was the same as that of Examples 1 to 4, but the synthetic leather of Comparative Example 1 without hairiness and the synthetic leathers of Comparative Examples 3 and 4 with hairiness but different knitting structure of the tricot warp knitted fabric from that of Examples 1 to 4 also had gathered wrinkles. Therefore, it can be considered that in order to suppress the generation of gathered wrinkles, it is necessary to make the fabric have an appropriate thickness by the combination of the knitting composition of the tricot warp knitted fabric and the formation of hairiness that causes the sinker camber to be raised.

[0133] In the synthetic leathers of Examples 1 to 6 in which the occurrence of gathering wrinkles was suppressed, the sum of the 5% circular modulus measured in the course direction and the 5% circular modulus measured in the wale direction was 24.66 to 41.86 N / 25.4 mm. On the other hand, in the synthetic leathers of Comparative Examples 1 to 5 in which gathering wrinkles were generated, the sum of the 5% circular modulus measured in the course direction and the 5% circular modulus measured in the wale direction was 45.64 to 52.55 N / 25.4 mm. It can be considered that in order to suppress the occurrence of gathering wrinkles, the sum of the 5% circular modulus of the synthetic leather in the course direction and the wale direction is preferably within the range of 23 to 45 N / 25.4 mm.

[0134] Industrial Applicability

[0135] The synthetic leather of the present invention can be used as an automobile interior material or an interior material, and is particularly suitable for use in curved chair seats, steering wheels, shoes, bags, and the like.

Claims

1. A synthetic leather, characterized in that: A resin layer is laminated on the fabric. The fabric is a tricot warp knitted fabric with hairiness woven by front yarn, middle yarn and back yarn. The tricot fabric comprises: a warp pile knitted structure knitted with the front yarn, a warp plain knitted structure knitted with the intermediate yarn, and an insert structure knitted with the back yarn. The hairiness is formed by raising the sinker loop surface of the tricot warp knitted fabric.

2. The synthetic leather according to claim 1, wherein The thickness of the cloth is 0.9 mm to 3.0 mm.

3. The synthetic leather according to claim 1 or 2, wherein: The warp pile knitted structure knitted with the front yarn is knitted in a manner that the number of needle backing yarns is 3 or more.

4. The synthetic leather according to claim 1 or 2, wherein: The inserted structure knitted with the back yarn is knitted in a manner that the number of needle back inlay yarns is three or more.

5. The synthetic leather according to claim 4, wherein The warp knit structure knitted using the intermediate yarn is knitted to form a closed loop.

6. The synthetic leather according to claim 1 or 2, wherein: The tricot knitted fabric has the hairiness of 65,000 to 850,000 yarns per 25.4 mm×25.4 mm and a total decimal point of 200,000 to 600,000 dtex.

7. The synthetic leather according to claim 1 or 2, wherein: The fineness of the front yarn is 44 dtex to 250 dtex.

8. The synthetic leather according to claim 1 or 2, wherein: The fineness of the intermediate yarn and the rear yarn is 30 dtex to 220 dtex respectively.

9. The synthetic leather according to claim 1 or 2, wherein: The single yarn fineness of the front yarn is 0.3dtex to 5.5dtex.

10. The synthetic leather according to claim 1 or 2, wherein: The single yarn fineness of the intermediate yarn and the rear yarn is 0.3 dtex to 5.5 dtex respectively.

11. The synthetic leather according to claim 1 or 2, wherein: The sum of the 5% circular modulus in the course direction of the tricot warp knitted fabric and the wale direction of the tricot warp knitted fabric is 23N / 25.4mm-45N / 25.4mm.

12. The synthetic leather according to claim 11, wherein The 5% circular modulus is 9N / 25.4mm-30N / 25.4mm in the course direction of the tricot warp knitted fabric, and is 10N / 25.4mm-22N / 25.4mm in the wale direction of the tricot warp knitted fabric.

13. The synthetic leather according to claim 1 or 2, wherein: The resin layer is stacked on the sinker arc surface side of the tricot warp knitted fabric, and the thickness of the resin layer is 100 μm to 280 μm.

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