Skin material and method for manufacturing the same

Abstract

To provide a skin material which is less likely to generate wrinkles by heating molding.SOLUTION: A skin material includes a fabric such that constituent fibers are fixed to each other by a core-shell type resin binder. The resin of a shell part and the resin of a core part constituting the core-shell type resin binder are different kinds of resins. A skin material which is less likely to generate wrinkles by heating molding can be provided by adopting the fabric such that the constituent fibers are fixed to each other by the core-shell type resin binder.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a skin material that is less likely to wrinkle during thermoforming and a method for manufacturing the same.

Background Art

[0002] Conventionally, as a skin material constituting interior materials, vehicle insulator materials, etc., for example, as described in Japanese Patent Application Laid-Open No. 2012-102437 (Patent Document 1), a skin material including a fabric in which constituent fibers are fixed by a binder has been used. In addition, in the examples of Patent Document 1, it is described that a core-shell type acrylic resin in which both the resin of the shell portion and the resin of the core portion are acrylic resins is adopted as the binder. And it is described that the skin material prepared in this way was excellent in followability without being recognized for the generation of wrinkles due to thermoforming even when thermoforming was performed at a temperature lower than 200°C.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to provide a skin material that is less likely to wrinkle during thermoforming, the applicant of the present application examined the skin material according to the prior art as described in the examples of Patent Document 1. Specifically, a skin material including a fabric in which constituent fibers are fixed by a core-shell type resin binder was examined. However, when the skin material according to the prior art is subjected to thermoforming using a mold having irregularities, or when it is subjected to thermoforming under higher temperature conditions than those described above, i.e., under severe thermoforming conditions, wrinkles may occur on the surface of the skin material after thermoforming. It was considered that the cause of this was that the skin material, which was warmed and softened during the thermoforming, unintentionally changed its shape and generated fine wrinkles in the mold. Therefore, an object of the present invention is to provide a skin material that is less likely to develop wrinkles during thermoforming.

Means for Solving the Problems

[0005] The present invention is “(Claim 1) A skin material comprising a fabric in which constituent fibers are fixed to each other by a core-shell type resin binder, wherein the resin of the shell portion and the resin of the core portion are different types of resins, Skin material. (Claim 2) The skin material according to claim 1, wherein the constituent fibers are also fixed to each other by a thermosetting resin. Skin material according to claim 1. (Claim 3) A method for manufacturing a skin material, comprising: (Step 1) A step of preparing a fabric, (Step 2) A step of preparing a core-shell type resin binder in which the resin of the shell portion and the resin of the core portion are composed of different types of resins, (Step 3) A step of preparing a binder liquid in which the core-shell type resin binder is dispersed in a dispersion medium, (Step 4) A step of applying the binder liquid to the fabric, (Step 5) A step of removing the dispersion medium by supplying the fabric to which the binder liquid has been applied to a heating device, (Step 6) A step of allowing to cool or cooling after supplying to the heating device. Comprising A method for manufacturing a skin material comprising a fabric in which constituent fibers are fixed to each other by the core-shell type resin binder.” It is.

Effects of the Invention

[0006] The surface material according to the present invention includes a fabric in which constituent fibers are fixed by a core-shell type resin binder, and the resin of the shell part (hereinafter sometimes referred to as resin S) and the resin of the core part (hereinafter sometimes referred to as resin C) constituting the core-shell type resin binder are different types of resins. In the present invention, the fact that resin S and resin C are different types of resins means that the chemical structures of the main chain parts connected by a certain chemical structure of resin S and the main chain parts connected by a certain chemical structure of resin C are different.

[0007] As a specific example, in the core-shell type resin binder used in the examples described later, when resin S is a polyester resin and resin C is an acrylic styrene resin, · Resin S is a resin having a main chain part connected by a chemical structure (-OCORCOO-), · Resin C is a resin having a main chain part connected by a chemical structure (-CH2CHCOO-) and a chemical structure (-CH2CHC6H5-), Also, · Resin S does not have a main chain part connected by a chemical structure (-CH2CHCOO-) and a chemical structure (-CH2CHC6H5-), · Since resin C does not have a main chain part connected by a chemical structure (-OCORCOO-), The resin of the shell part and the resin of the core part are different types of resins. In the above chemical structure, R means an alkyl bond composed of carbon and hydrogen or a saturated or unsaturated cycloalkyl bond, and for example, R can be C6H4.

[0008] On the other hand, in the core-shell type acrylic resin described in Patent Document 1, both resin S and resin C are acrylic resins, · Since both Resin S and Resin C are resins having a main chain portion connected by a chemical structure (-CHCOOCH3-) and a chemical structure (-CCH3COOCH3-), The resin of the shell portion and the resin of the core portion are of the same type.

[0009] The applicant of the present application has found that by adopting a fabric in which constituent fibers are fixed by the core-shell type resin binder according to the present invention, it is possible to provide a skin material that is less likely to wrinkle by heat molding.

[0010] The reason why this effect is exhibited has not been fully clarified, but the applicant of the present application believes that the following effects are exhibited.

[0011] When the skin material is subjected to heat molding under severe conditions, in order to prevent wrinkles from occurring and heat-mold the skin material, it is desirable that the skin material has appropriate rigidity even during heat molding. When Resin S and Resin C that constitute the core-shell type resin binder provided in the skin material are of the same type of resin, it is considered that the behavior of physical property changes (for example, ease of deformation, etc.) of Resin S and Resin C that occur during the heat molding of the skin material is similar. Therefore, when the skin material is subjected to the heat molding process, the presence of Resin S and Resin C with similar physical property change behaviors causes the core-shell type resin binder to easily cause rapid physical property changes (for example, ease of deformation, etc.). As a result, the skin material in which the constituent fibers are fixed by the core-shell type resin binder becomes rapidly soft and its rigidity is likely to decrease unintentionally during heat molding. From the above, it is considered that an unintended shape change is likely to occur during heating, and particularly when subjected to heat molding under severe conditions, wrinkles are likely to occur.

[0012] On the other hand, when the resin S and the resin C that constitute the core-shell type resin binder provided in the skin material are different types of resins, it is considered that the behaviors of the physical property changes (for example, ease of deformation, etc.) of the resin S and the resin C that occur during the heat molding of the skin material are greatly different. Therefore, when the skin material is subjected to the heat molding process, the presence of the resin S and the resin C with greatly different behaviors of physical property changes causes the core-shell type resin binder to cause stepwise physical property changes (for example, ease of deformation, etc.), so it is difficult to cause rapid physical property changes. As a result, the skin material in which the constituent fibers are fixed to each other by the core-shell type resin binder becomes gently soft during heat molding and is unlikely to have its rigidity decreased unintentionally.

[0013] From the above, since the occurrence of unintended shape changes during heating is prevented, it is considered that wrinkles are unlikely to occur even when subjected to heat molding under particularly severe conditions.

[0014] Further, in another aspect of the present invention, the constituent fibers of the fabric provided in the skin material are also fixed by a thermosetting resin. By having such a configuration, it is a skin material having a further function that fluffing is unlikely to occur even when heat molded. For example, when the skin material is subjected to heat molding using a mold, the surface portion of the skin material comes into contact with the mold, and it becomes easy for the fixing between the constituent fibers fixed by the core-shell type resin binder to come off. As a result, fluffing was likely to occur on the surface of the heat-molded skin material. On the other hand, in another aspect of the present invention, the constituent fibers are also fixed by a thermosetting resin. Therefore, for example, when the skin material is subjected to heat molding using a mold, even if the surface portion of the skin material comes into contact with the mold, the constituent fibers are fixed to each other by the thermosetting resin, so it is difficult for the fixing between the constituent fibers to come off. As a result, the occurrence of fluffing on the surface of the heat-molded skin material is prevented.

[0015] And, by the method for manufacturing a skin material according to the present invention, a skin material having the configuration according to claim 1 can be provided. Note that, by adopting a binder liquid containing a core-shell type resin binder and a thermosetting resin, a skin material having the configuration according to claim 2 can be provided.

Embodiments for Carrying Out the Invention

[0016] In the present invention, various configurations such as the following configurations can be appropriately selected. Note that, unless otherwise specified, all the various measurements described in the present invention are carried out under atmospheric pressure. Further, unless otherwise specified, all the various measurements described in the present invention are carried out under the temperature condition of 25°C. And, unless otherwise specified, all the various measurement results described in the present invention are measured up to a value one digit smaller than the required value, and the required value is calculated by rounding off the obtained value. As a specific example, when the value up to the first decimal place is the required value, the value up to the second decimal place is obtained by measurement, and the value up to the first decimal place is calculated by rounding off the obtained value of the second decimal place, and this value is taken as the required value.

[0017] The skin material according to the present invention includes a fabric. The fabric referred to in the present invention is, for example, a fiber sheet such as a non-woven fabric, a woven fabric, or a knitted fabric. Since the skin material according to the present invention includes a fabric (particularly, a non-woven fabric), it has characteristics such as excellent followability to a mold and is easily deformed into a desired three-dimensional shape. Therefore, it is possible to provide a skin material that is less likely to develop wrinkles by heat molding.

[0018] The constituent fibers of the fabric can be made of known resins such as polyolefin resins (e.g., polyethylene, polypropylene, polyolefin resins with a structure in which a part of hydrocarbons is substituted with a cyano group or a halogen such as fluorine or chlorine), polymethylpentene, styrene resins, polyvinyl alcohol resins, polyether resins (e.g., polyether ether ketone, polyacetal, modified polyphenylene ether, aromatic polyether ketone, etc.), polyester resins (e.g., polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polycarbonate, polyarylate, wholly aromatic polyester resin, etc.), polyimide resins, polyamideimide resins, polyamide resins (e.g., aromatic polyamide resins, aromatic polyetheramide resins, nylon resins, etc.), resins having a nitrile group (e.g., polyacrylonitrile, etc.), urethane resins, epoxy resins, polysulfone resins (e.g., polysulfone, polyether sulfone, etc.), fluorine resins (e.g., polytetrafluoroethylene, polyvinylidene fluoride, etc.), cellulose resins, polybenzimidazole resins, acrylic resins (e.g., polyacrylonitrile-based resins copolymerized with acrylic acid esters or methacrylic acid esters, modacrylic resins copolymerized with acrylonitrile and vinyl chloride or vinylidene chloride, etc.). In particular, since it is easy to provide a skin material having excellent touch and suitable for use as an interior material or a vehicle insulator material, the constituent fibers preferably contain a polyester resin.

[0019] Note that these resins may be composed of either linear polymers or branched polymers, and the resins may be block copolymers or random copolymers. Also, the three-dimensional structure or the presence or absence of crystallinity of the resins is not particularly limited. Furthermore, a mixture of multi-component resins may be used. Also, the constituent fibers may be original fibers such as fibers prepared by kneading pigments or dyed fibers.

[0020] In addition, when flame retardancy is required for the surface material, it is preferable that the constituent fibers of the fabric contain a flame-retardant resin. Examples of such flame-retardant resins include modacrylic resin, vinylidene resin, polyvinyl chloride resin, polyvinylidene fluoride resin, novoloid resin, polyvinyl chloride resin, polyester resin copolymerized with a phosphorus compound, acrylic resin copolymerized with a halogen-containing monomer, aramid resin, and resin kneaded with a halogen-based, phosphorus-based, or metal compound-based flame retardant.

[0021] The constituent fibers of the fabric can be obtained by known methods such as, for example, the melt spinning method, dry spinning method, wet spinning method, direct spinning method (melt blowing method, spunbond method, electrospinning method, etc.), a method of extracting fine fibers by removing one or more resin components from composite fibers, and a method of obtaining fibers by beating and dividing fibers.

[0022] In addition to circular and elliptical fibers, the constituent fibers of the fabric may include fibers with a deformed cross-section. The fibers with a deformed cross-section may have a fiber cross-section such as a hollow shape, a polygonal shape such as a triangular shape, an alphabetic character type shape such as a Y shape, an irregular shape, a multi-leaf shape, a symbol type shape such as an asterisk shape, or a shape in which a plurality of these shapes are combined.

[0023] When the fabric contains heat-fusible fibers as constituent fibers, it is preferable to impart strength and shape stability to the fabric by heat-fusing the fibers together. Such heat-fusible fibers may be fully fused type heat-fusible fibers or partially fused type heat-fusible fibers.

[0024] When the fabric contains crimpable fibers, it is preferable because it can provide interior and exterior materials with increased stretchability and prevention of wrinkles on the surface, which are rich in design. As such crimpable fibers, for example, crimpable fibers in which the crimp of latent crimpable fibers is expressed or fibers with crimp can be used.

[0025] The fineness of the constituent fibers of the fabric is appropriately adjusted, but it is preferably 10 dtex or less, more preferably 5 dtex or less, and still more preferably 2.2 dtex or less, so as to provide a skin material that is less likely to wrinkle due to heat forming. On the other hand, the lower limit value can be appropriately adjusted, but 0.1 dtex is realistic.

[0026] Also, the fiber length of the constituent fibers of the fabric is appropriately adjusted, but it is preferably 20 mm or more, more preferably 25 mm or more, and still more preferably 30 mm or more, so as to have characteristics such as excellent followability to the mold and being easily deformed into a desired three-dimensional shape, and to provide a skin material that is less likely to wrinkle due to heat forming. On the other hand, when the fiber length exceeds 110 mm, fiber lumps tend to be formed during the preparation of the fabric (especially non-woven fabric), and wrinkles are likely to occur due to heat forming. Therefore, the fiber length is preferably 110 mm or less, and more preferably 60 mm or less. The "fiber length" refers to the value measured in accordance with JIS L1015 (2010), 8.4.1 c) direct method (method C).

[0027] When the fabric is a non-woven fabric, the non-woven fabric can be prepared by, for example, a dry method in which the above-mentioned fibers are supplied to a carding device or an air-laying device to entangle the fibers to prepare a web, a wet method in which the fibers are dispersed in a solvent and the fibers are entangled in a sheet form to prepare a web, or a method of spinning the fibers using a direct spinning method (melt blowing method, spunbond method, electrospinning method, a method of discharging a spinning dope and a gas stream in parallel to spin the fibers (for example, the method disclosed in JP-A-2009-287138)) and collecting the same to prepare a web.

[0028] Then, a nonwoven fabric can be prepared by entangling and / or integrating the prepared web. Examples of methods for entangling and / or integrating the constituent fibers include, for example, a method of entangling by needles or water flow, and a method of integrating the constituent fibers of the web by subjecting them to heat treatment to melt or soften a part of the constituent fibers and bonding them. The method of heat treatment can be appropriately selected. For example, a method of heating or heating and pressing by rolls, a method of heating by supplying to a heating machine such as an oven dryer, a far-infrared heater, a dry heat dryer, a hot air dryer, or a method of heating by irradiating infrared rays under no pressure can be used.

[0029] Various configurations of the fabric, such as the basis weight and thickness, should not be particularly limited and can be adjusted as appropriate.

[0030] The basis weight can be, for example, 10 to 200 g / m 2 and can be 30 to 150 g / m 2 and can be 35 to 120 g / m 2 In the present invention, the basis weight refers to the mass per 1 m 2 on the surface (main surface) having the largest area of the fabric.

[0031] Also, the thickness can be 0.5 to 3 mm, can be 0.7 to 2.5 mm, and can be 0.8 to 1.9 mm. In the present invention, the "thickness" means the arithmetic mean value of the length values between both main surfaces of the fabric under a load of 100 g / 5 cm 2 measured at randomly selected 10 points.

[0032] In the skin material according to the present invention, the constituent fibers of the fabric are fixed by a core-shell type resin binder. Here, "the constituent fibers are fixed by a core-shell type resin binder" means (Aspect 1) An aspect in which an aggregate formed by the aggregation of a core-shell type resin binder covers a plurality of constituent fibers, and the plurality of constituent fibers are tied together by the aggregate, or (Aspect 2) A mode in which constituent fibers of a fabric are adhered to each other by a core-shell type resin binder that has solidified after melting or softened. It can be.

[0033] Whether or not the constituent fibers of the fabric included in the skin material are fixed by a core-shell type resin binder can be confirmed by the following method.

[0034] (Aspect 1: Method for confirming whether constituent fibers are tied together by aggregates of a core-shell type resin binder) (Step 1) Collect a fabric (for example, a non-woven fabric) to be measured from the skin material. (Step 2) Prepare a staining solution (for example, Kayastain Q (manufactured by Nippon Kayaku Co., Ltd.)) that can stain the shell portion of the core-shell type resin binder. (Step 3) Collect aggregates of binder particles that tie together the constituent fibers from the skin material. (Step 4) After staining the aggregates of binder particles with the staining solution, cut the aggregates and photograph the cross-section of the cut aggregates with an optical microscope at 200 times magnification to obtain an optical micrograph. If the aspect of the cross-section cannot be confirmed even when using an optical microscope at 200 times magnification, it is possible to photograph with an optical microscope at a higher magnification to obtain an optical micrograph. (Step 5) Visually check the obtained optical micrograph. If the binder particles constituting the aggregates have a central portion (core portion) made of resin and a surrounding portion (shell portion) made of resin covering the central portion, it is determined that the fabric from which the sample was collected has constituent fibers fixed by a core-shell type resin binder.

[0035] On the other hand, if there are no aggregates of binder particles that fix the constituent fibers of the fabric to each other, or if the binder particles constituting the aggregates do not have a core portion and a shell portion, it is determined that the fabric from which the sample was collected does not have constituent fibers fixed to each other by a core-shell type resin binder.

[0036] (Aspect 2: Method for confirming whether constituent fibers are adhered by a core-shell type resin binder that solidifies after melting or softening) (Step 1) Collect a fabric (e.g., non-woven fabric) to be measured from the skin material. (Step 2) Prepare a stainable staining solution (e.g., Kayastain Q (manufactured by Nippon Kayaku Co., Ltd.)) for the shell portion of the core-shell type resin binder. (Step 3) Stain the binder component that adheres the constituent fibers contained in the fabric using the staining solution. (Step 4) Cut the stained fabric in the thickness direction, and photograph the cross-section of the cut fabric with an optical microscope at 200 times magnification to obtain an optical microscope photograph. If the aspect of the cross-section cannot be confirmed even using an optical microscope at 200 times magnification, it is possible to obtain an optical microscope photograph by photographing with an optical microscope at a higher magnification. (Step 5) Visually check the obtained optical microscope photograph. When the binder component has a central portion (core portion) made of resin and a surrounding portion (shell portion) made of resin covering the central portion, and the constituent fibers of the fabric are adhered by the shell portion, it is determined that the fabric from which the sample was collected has constituent fibers adhered by a core-shell type resin binder.

[0037] On the other hand, when there is no binder component that adheres the constituent fibers of the fabric, or when the constituent fibers of the fabric are adhered by the binder component but the binder component does not have a core portion and a shell portion, it is determined that the fabric from which the sample was collected does not have constituent fibers adhered by a core-shell type resin binder.

[0038] Furthermore, the core-shell type resin binder according to the present invention is characterized in that the resin S of the shell portion and the resin C of the core portion are different types of resins. In the present invention, the fact that the resin S and the resin C are different types of resins means that the chemical structure of the main chain portion connected by a certain chemical structure possessed by the resin S is different from the chemical structure of the main chain portion connected by a certain chemical structure possessed by the resin C.

[0039] Incidentally, whether the resin S and the resin C that constitute the core-shell type resin binder are different types of resins can be confirmed by the following method.

[0040] (Method for confirming whether the resin S and the resin C are different types of resins) (Step 1) In the measurement result of (the method for confirming whether the constituent fibers are fixed by the core-shell type resin binder) described above, prepare a fabric that is determined to have the constituent fibers fixed by the core-shell type resin binder. (Step 2) Collect the core-shell type resin binder from the fabric. The collection method can be appropriately selected, and methods such as cutting out the core-shell type resin binder from the fabric, and extracting the core-shell type resin binder using a solvent that can dissolve only the resin S and / or the resin C without dissolving the constituent fibers of the fabric can be adopted. (Step 3) Obtain the resin S and the resin C from the core-shell type resin binder collected from the fabric, such as the cut core-shell type resin binder or the core-shell type resin binder dissolved in the solvent, by the same method. Subject the obtained resin S and resin C to various known analytical apparatuses and various analytical methods such as IR, DSC, NMR, MS, Raman spectroscopy, elemental analysis, and combustion test. As a result of subjecting to various analytical apparatuses and various analytical methods, if the chemical structures of the main chain portions connected by a certain chemical structure of the resin S and the main chain portions connected by a certain chemical structure of the resin C are different, it is determined that the resin S and the resin C are different types of resins. On the other hand, if the chemical structures of the main chain portions connected by a certain chemical structure of the resin S and the resin C are the same, it is determined that the resin S and the resin C are the same type of resins.

[0041] Incidentally, if the manufacturing process of the skin material is known and the resin S and the resin C are known for the core-shell type resin binder to be included in the fabric, it is possible to determine whether the resin S and the resin C are different types of resins based on the chemical structures of the resin S and the resin C.

[0042] The types of the above-mentioned resin S and resin C are appropriately selected. For example, polyolefin resins (such as modified polyolefins), ethylene-vinyl alcohol copolymers, ethylene-acrylate copolymers such as ethylene-ethyl acrylate copolymers, various rubbers and their derivatives (styrene-butadiene rubber (SBR), fluorine-based resins such as fluororubbers, urethane rubber, ethylene-propylene-diene rubber (EPDM), etc.), cellulose derivatives (such as carboxymethyl cellulose (CMC), hydroxyethyl cellulose, hydroxypropyl cellulose, etc.), polyvinyl alcohol (PVA), polyvinyl butyral (PVB), polyvinyl pyrrolidone (PVP), polyurethane, epoxy resin, polyvinylidene fluoride (PVdF), vinylidene fluoride-hexafluoropropylene copolymer (PVdF-HFP), acrylic resins (such as vinyl versatic acid copolymer acrylic resins), etc. can be used.

[0043] In addition, the resin S and / or resin C may contain additives such as flame retardants, fragrances, pigments, antibacterial agents, antifungal agents, photocatalyst particles, etc.

[0044] Also, the relationship between the melting point and / or glass transition temperature of the resin in the core part and the resin in the shell part constituting the core-shell type resin binder can be appropriately selected so that it is easy to prepare a skin material that is less likely to develop wrinkles by heat molding. The resin in the shell part may have a lower melting point and / or glass transition temperature than the resin in the core part, or the resin in the shell part may have a higher melting point and / or glass transition temperature than the resin in the core part.

[0045] As specific combinations of the resin S and the resin C constituting the core-shell type resin binder according to the present invention, for example, the following combinations can be mentioned. (Example 1) A combination in which resin S is a polyester-based resin and resin C is an acrylic styrene-based resin. · Resin S is a resin having a main chain part connected by a chemical structure (-OCORCOO-), · Resin C is a resin having a main chain portion connected by a chemical structure (-CH2CHCOO-) and a chemical structure (-CH2CHC6H5-), Also, · Resin S does not have a main chain portion connected by a chemical structure (-CH2CHCOO-) and a chemical structure (-CH2CHC6H5-), · Resin C does not have a main chain portion connected by a chemical structure (-OCORCOO-).

[0046] (Example 2) A combination where resin S is an acrylic resin and resin C is a silicone resin. · Resin S is a resin having a main chain portion connected by a chemical structure (-CH2CHCOO-), · Resin C is a resin having a main chain portion connected by a chemical structure (-SiO-), Also, · Resin S does not have a main chain portion connected by a chemical structure (-SiO-), · Resin C does not have a main chain portion connected by a chemical structure (-CH2CHCOO-).

[0047] (Example 3) A combination where resin S is a polyester resin and resin C is an acrylic resin. · Resin S is a resin having a main chain portion connected by a chemical structure (-OCORCOO-), · Resin C is a resin having a main chain portion connected by a chemical structure (-CH2CHCOO-), Also, · Resin S does not have a main chain portion connected by a chemical structure (-CH2CHCOO-), · Resin C does not have a main chain portion connected by a chemical structure (-OCORCOO-).

[0048] (Example 4) A combination where resin S is an acrylonitrile resin and resin C is an acrylic resin. · Resin S is a resin having a main chain portion connected by a chemical structure (-CHCN-). · Resin C is a resin having a main chain portion connected by a chemical structure (-CH2CHCOO-), Also, · Resin S does not have a main chain portion connected by a chemical structure (-CH2CHCOO-), · Resin C does not have a main chain portion connected by a chemical structure (-CHCN-).

[0049] The basis weight of the core-shell type resin binder contained in the fabric is appropriately selected so as to provide a skin material that satisfies the configuration of the present invention. Specifically, it can be 0.1 to 100 g / m 2 and can be 0.5 to 50 g / m 2 and can be 0.7 to 30 g / m 2 and can be.

[0050] Also, so that the skin material has a further function that fuzzing hardly occurs even when heat-formed, it is preferable that the constituent fibers of the fabric included in the skin material are fixed not only by the core-shell type resin binder but also by a thermosetting resin. The type of thermosetting resin can be appropriately selected. For example, epoxy resin, oligoester acrylate, xylene resin, guanamine resin, diallyl phthalate resin, DFK resin, thermosetting resin prepolymer, vinyl ester resin, phenol resin, unsaturated polyester resin, furan resin, polyimide resin, poly(p-hydroxybenzoic acid) resin, polyurethane resin, maleic acid resin, melamine resin, urea resin, etc. can be used. Further, a thermosetting resin such as a polymer containing an oxazoline group, a methylol group, an isocyanate group, an epoxy group, a silanol group, a hydrazide group, an acetoacetyl group, etc. can be adopted. In particular, when the constituent fibers of the fabric included in the skin material are also fixed by melamine resin, it is a preferable skin material excellent in water resistance, weather resistance, and chemical resistance in addition to hardly generating fuzzing.

[0051] As used herein, "the constituent fibers are fixed by a thermosetting resin" means a state in which the constituent fibers of the fabric are adhered to each other by a heated and cured thermosetting resin.

[0052] Whether or not the constituent fibers of the fabric included in the skin material are fixed by a thermosetting resin can be confirmed by, in addition to reading the core-shell type resin binder as a thermosetting resin in the above-described (Aspect 2: Confirmation method of whether or not the constituent fibers are adhered by a core-shell type resin binder solidified after melting or softening), replacing (Step 2) with the following (Step 2') and (Step 5) with the following (Step 5').

[0053] (Step 2') Prepare a staining solution capable of staining the thermosetting resin (for example, Kayastain Q (manufactured by Nippon Kayaku Co., Ltd.)).

[0054] (Step 5') Visually check the obtained optical micrograph. When the constituent fibers of the fabric are adhered to each other by a thermosetting resin, it is determined that the fabric from which the sample was taken has constituent fibers adhered by a thermosetting resin.

[0055] The mass percentage of the thermosetting resin in the sum of the masses of the core-shell type resin binder and the thermosetting resin contained in the fabric included in the skin material (hereinafter referred to as the mass percentage of the thermosetting resin) is appropriately adjusted so that the skin material is less likely to generate fluff. For example, the mass percentage of the thermosetting resin is preferably 0.1% by mass or more, more preferably 1% by mass or more, still more preferably 3% by mass or more, still more preferably 5% by mass or more, still more preferably 10% by mass or more, still more preferably 20% by mass or more, and most preferably 30% by mass or more. The upper limit value is appropriately adjusted so that it is easy to prepare a skin material that is less likely to generate wrinkles by heat molding, but is preferably 90% by mass.

[0056] A fabric in which constituent fibers are fixed by a core-shell type resin binder, or a fabric in which constituent fibers are fixed by a core-shell type resin binder and a thermosetting resin can be used alone as a skin material. However, a support (for example, a separately prepared fabric, a porous or non-porous film, a foam, etc.) may be laminated on the fabric, and / or a skin material may be provided with a print or a resin layer, etc. on the entire main surface or a part of the main surface of the fabric.

[0057] Various configurations of the skin material, such as basis weight and thickness, should not be particularly limited and can be adjusted as appropriate. For example, the basis weight can be 10 to 200 g / m 2 and can be 30 to 150 g / m 2 and can be 45 to 120 g / m 2 Also, the thickness can be 0.5 to 3.0 mm, can be 0.7 to 2.5 mm, and can be 0.8 to 1.9 mm.

[0058] Next, a method for manufacturing the skin material of the present invention will be described. Note that the description will be omitted for the same items and configurations as those described for the above skin material. The manufacturing method of the skin material according to the present invention can be appropriately selected. As an example, (Step 1) A step of preparing a fabric, (Step 2) A step of preparing a core-shell type resin binder in which the resin in the shell portion and the resin in the core portion are made of different types of resins, (Step 3) A step of preparing a binder liquid in which the core-shell type resin binder is dispersed in a dispersion medium, (Step 4) A step of applying the binder liquid to the fabric, (Step 5) A step of removing the dispersion medium by supplying the fabric to which the binder liquid has been applied to a heating device, (Step 6) A step of allowing to cool or cooling after being supplied to the heating device, is provided, A method for manufacturing a skin material including a fabric in which constituent fibers are fixed by the core-shell type resin binder can be mentioned.

[0059] (Step 3) will be described.

[0060] The type of dispersion medium can be appropriately selected. However, in order to preferably apply the binder liquid to the fabric, it is preferable to adopt a dispersion medium in which the core-shell type resin binder is insoluble and dispersible. Further, the binder liquid may contain additives such as a flame retardant, a fragrance, a pigment, an antibacterial agent, an antifungal agent, photocatalyst particles, an emulsifier, a dispersant, a surfactant, and a thickener.

[0061] Alternatively, the binder liquid may contain a resin other than the core-shell type resin binder. Since the fabric contains a thermosetting resin, it is possible to prevent the skin material from sticking to the mold during heat molding and improve the releasability. That is, it is possible to suppress the fluffing due to the deterioration of the releasability caused by the sticking of the core-shell type resin binder. When the binder liquid contains a thermosetting resin, the dispersion medium may be one that can dissolve the thermosetting resin or one that can disperse the thermosetting resin. Further, since the fabric contains a thermosetting resin, it is possible to provide a skin material having excellent trimming properties.

[0062] (Step 4) will be described.

[0063] The method of applying the binder liquid to the fabric can be appropriately selected. For example, a method of spraying or coating the binder liquid as it is or in a foamed state on one main surface of the fabric using a spray or an impregnating roll, or a method of immersing the fabric in the binder liquid can be adopted.

[0064] (Step 5) will be described.

[0065] The type of heating device can be appropriately selected. For example, an oven dryer, an infrared heater, a dry heat dryer, a hot air dryer, etc. can be adopted. The lower limit of the heating temperature is adjusted so that the dispersion medium can be volatilized.

[0066] In addition, when the binder liquid applied to the fabric contains a thermosetting resin, by curing the thermosetting resin through heating with a heating device, the constituent fibers of the fabric can be adhered and fixed to each other by the cured thermosetting resin. Therefore, when the binder liquid applied to the fabric contains a thermosetting resin, the lower limit of the heating temperature is the temperature at which the solvent or dispersion medium constituting the binder liquid can volatilize, and is adjusted to be the temperature at which the thermosetting resin cures.

[0067] Also, the upper limit of the heating temperature is selected so that the shape and function of the constituent members of the fabric such as the constituent fibers do not decrease unintentionally. At this time, the resin S of the core-shell type resin binder may be melted or softened to adhere the constituent fibers of the fabric to each other with the resin S.

[0068] The (Step 6) will be described.

[0069] The method of allowing to cool or cooling can be appropriately selected. For example, methods such as allowing to cool at room temperature, cooling by applying room temperature air or cold air, and cooling by exposing to a low temperature space such as placing in a refrigerator can be adopted.

[0070] Using the fabric prepared as described above as the skin material, it can be directly supplied to the molding process to prepare an interior material or a vehicle insulator material. However, it may also include a step of laminating a support on the fabric and / or applying a print or a resin layer etc. to the entire main surface or a part of the main surface of the fabric.

[0071] In addition, according to the use and usage mode, after subjecting it to various secondary processes such as a process of processing by punching etc. so that the skin material prepared as described above becomes the intended shape, and a process of adjusting various physical properties such as thickness and surface smoothness such as a resilient press treatment, it may be supplied to the heating molding process using a mold.

Examples

[0072] Hereinafter, the present invention will be specifically described by way of examples, but these do not limit the scope of the present invention.

[0073] (Preparation of Binder Liquid)

[0074] (Binder Liquid A1) A core-shell type resin binder A (resin S: polyester resin (glass transition temperature: 55 °C), resin C: acrylic styrene resin (glass transition temperature: 0 °C), resin S: resin C = 60% by mass: 40% by mass), and a water dispersion containing a thermosetting resin (melamine resin that cures at at least 135 °C) (solid content concentration of core-shell type resin binder A: 3.50% by mass, solid content concentration of thermosetting resin: 1.19% by mass). Note that the core-shell type resin binder A · Resin S is a resin having a main chain portion connected by a chemical structure (-OCORCOO-), · Resin C is a resin having a main chain portion connected by a chemical structure (-CH2CHCOO-) and a chemical structure (-CH2CHC6H5-), Also, · Resin S does not have a main chain portion connected by a chemical structure (-CH2CHCOO-) and a chemical structure (-CH2CHC6H5-), · Since resin C does not have a main chain portion connected by a chemical structure (-OCORCOO-), the resin in the shell portion and the resin in the core portion are different types of resins.

[0075] (Binder Liquid B) A core-shell type resin binder B (resin S: acrylic resin (glass transition temperature: -50 °C), resin C: acrylic resin (glass transition temperature: 50 °C), resin S: resin C = 32% by mass: 68% by mass, solid content concentration of core-shell type resin binder: 35% by mass), and a water dispersion containing a thermosetting resin (melamine resin that cures at at least 135 °C) (solid content concentration of core-shell type resin binder B: 3.50% by mass, solid content concentration of thermosetting resin: 1.19% by mass). Note that the core-shell type resin binder B · Since both resin S and resin C are resins having a main chain portion connected by a chemical structure (-CHCOOCH3-) and a chemical structure (-CCH3COOCH3-), The resin in the shell portion and the resin in the core portion are of the same type.

[0076] (Binder liquid C) An aqueous dispersion containing a polyester resin binder (glass transition temperature: 15 °C, solid content concentration of the polyester resin binder: 30% by mass) and a thermosetting resin (a melamine resin that cures at at least 135 °C) (solid content concentration of the polyester resin binder: 3.50% by mass, solid content concentration of the thermosetting resin: 1.19% by mass).

[0077] (Binder liquid A2) An aqueous dispersion containing a core-shell type resin binder A and a thermosetting resin (a melamine resin that cures at at least 135 °C) (solid content concentration of the core-shell type resin binder A: 0.91% by mass, solid content concentration of the thermosetting resin: 1.96% by mass).

[0078] (Binder liquid A3) An aqueous dispersion containing a core-shell type resin binder A and a thermosetting resin (a melamine resin that cures at at least 135 °C) (solid content concentration of the core-shell type resin binder A: 1.96% by mass, solid content concentration of the thermosetting resin: 0.91% by mass).

[0079] (Binder liquid D1) An aqueous dispersion containing a core-shell type resin binder A and a thermosetting resin (an oxazoline group-containing polymer that cures at at least 135 °C) (solid content concentration of the core-shell type resin binder A: 2.84% by mass, solid content concentration of the thermosetting resin: 0.03% by mass).

[0080] (Binder liquid D2) An aqueous dispersion containing a core-shell type resin binder A and a thermosetting resin (an oxazoline group-containing polymer that cures at at least 135 °C) (solid content concentration of the core-shell type resin binder A: 2.73% by mass, solid content concentration of the thermosetting resin: 0.13% by mass).

[0081] (Binder liquid D3) A core-shell type resin binder A and an aqueous dispersion containing a thermosetting resin (an oxazoline group-containing polymer that cures at at least 135 °C) (solid content concentration of the core-shell type resin binder A: 2.80% by mass, solid content concentration of the thermosetting resin: 0.06% by mass).

[0082] (Example 1) Using 100 parts by mass of polypropylene fibers (fineness: 4 dtex, fiber length: 76 mm), fibrillation was carried out by a carding machine to form web A. Then, 25% by mass of rayon fibers (fineness: 1.7 dtex, fiber length: 51 mm) and 75% by mass of polyethylene terephthalate fibers (fineness: 2.2 dtex, fiber length: 51 mm) were mixed and carded to form web B by fibrillation. Thereafter, web A and web B were laminated, and needle punching treatment was performed from the web B side at a needle density of 400 needles / cm 2 to entangle the constituent fibers of both webs with each other. Then, binder liquid A1 was applied in a foamed state to the entire main surface opposite to the main surface on the side where the needle punching treatment was performed. Thereafter, the dispersion medium of binder liquid A1 was removed by drying with a dryer at a temperature of 135 °C, and it was allowed to cool to prepare a nonwoven fabric. The nonwoven fabric thus prepared was used as a skin material.

[0083] (Comparative Example 1) A nonwoven fabric was prepared in the same manner as in Example 1, except that binder liquid B was used instead of binder liquid A1. The nonwoven fabric thus prepared was used as a skin material.

[0084] (Comparative Example 2) A nonwoven fabric was prepared in the same manner as in Example 1, except that binder liquid C was used instead of binder liquid A1. The nonwoven fabric thus prepared was used as a skin material.

[0085] In addition, in all of the nonwoven fabrics prepared in Example 1 and Comparative Examples 1 to 2, aggregates formed by the aggregation of the core-shell type resin binder covered the constituent fibers of the nonwoven fabric, and thus a plurality of constituent fibers were tied and fixed by the aggregates. Furthermore, the constituent fibers were also adhered and fixed by the cured thermosetting resin.

[0086] The various configurations of the skin material (nonwoven fabric) prepared as described above are summarized in Table 1. For configurations not present, a "-" mark was described in the table.

[0087]

Table 1

[0088] For each of the skin materials prepared in Example 1 and Comparative Examples 1 to 2, the presence or absence of wrinkles generated by heat molding was confirmed by the following method, and the evaluation results are summarized in Table 2.

[0089] (Method for confirming the generation of wrinkles by heat molding) (Step 1) A base material formed by laminating a glass sheet, a foamed urethane, a glass sheet, and a polyethylene terephthalate film in this order was prepared. (Step 2) The prepared skin material was laminated on the main surface of the base material on the side where the polyethylene terephthalate film was exposed. (Step 3) With the skin material and the base material laminated, they were sandwiched between a pair of upper and lower molds having unevenness inside, and heat molding was performed by applying heat and pressure for heat pressing (molding temperature: 210 °C). Then, after cooling, a three-dimensionally molded skin material was prepared. (Step 4) The main surface of the bent valley portion in the prepared three-dimensionally molded skin material was visually observed. As a result of visual observation, a skin material in which no wrinkles were observed on the surface of the valley portion was evaluated as "〇". On the other hand, a skin material in which wrinkles were generated on the surface of the valley portion was evaluated as "×". In this confirmation method, a skin material evaluated as "〇" is a skin material that can prevent the generation of wrinkles by heat molding, and a skin material evaluated as "×" is a skin material that is likely to generate wrinkles by heat molding.

[0090]

Table 2

[0091] From the results of comparing Example 1 with Comparative Examples 1 to 2, it was found that the core-shell type resin binder according to the present invention can provide a skin material that is less likely to wrinkle during heat molding because the constituent fibers are fixed to each other.

[0092] (Example 2) 25% by mass of rayon fibers (fineness: 1.7 dtex, fiber length: 51 mm) and 75% by mass of flame-retardant polyester resin fibers (fineness: 1.3 dtex, fiber length: 51 mm) copolymerized with a phosphorus compound were mixed and opened by a carding machine to form web C. A non-woven fabric was prepared in the same manner as in Example 1, except that web C was used instead of web B, and binder liquid A2 was used instead of binder liquid A1 and the coating amount was reduced. The non-woven fabric thus prepared was used as the skin material.

[0093] (Example 3) A non-woven fabric was prepared in the same manner as in Example 2, except that binder liquid A3 was used instead of binder liquid A2. The non-woven fabric thus prepared was used as the skin material.

[0094] (Example 4) A non-woven fabric was prepared in the same manner as in Example 2, except that web C with an increased basis weight was used and the coating amount of binder liquid A2 was increased. The non-woven fabric thus prepared was used as the skin material.

[0095] (Example 5) A non-woven fabric was prepared in the same manner as in Example 4, except that binder liquid A3 was used instead of binder liquid A2. The non-woven fabric thus prepared was used as the skin material.

[0096] In addition, for the nonwoven fabrics prepared in Examples 2 to 5, in each case, aggregates formed by the aggregation of the core-shell type resin binder covered the constituent fibers of the nonwoven fabric, and thus a plurality of constituent fibers were connected and fixed by the aggregates. Furthermore, the constituent fibers were also adhered and fixed by the cured thermosetting resin.

[0097] The various configurations of the skin material (nonwoven fabric) prepared as described above are summarized in Table 3. For configurations not present, a "-" mark was described in the table.

[0098] [Table 3]

[0099] For each of the skin materials prepared in Examples 2 to 5, the presence or absence of wrinkles generated by thermoforming was confirmed by the method described above, and the evaluation results were summarized in Table 4 together with the evaluation results of Example 1.

[0100] Furthermore, by the following method, for each of the skin materials prepared in Examples 1 to 5, the presence or absence of fluff on the main surface after thermoforming was confirmed, and the evaluation results were summarized in Table 4. In addition, the mass percentage (unit: mass%) of the thermosetting resin was also noted in the table.

[0101] (Method for confirming fluff after thermoforming) The main surface of the three-dimensional formed skin material prepared in (Step 4) described above was visually observed to confirm the presence or absence of fluff. A skin material in which the presence of fluff was not recognized was evaluated as "none".

[0102] [Table 4]

[0103] As a result of checking the presence or absence of wrinkles generated by heat molding for the skin materials prepared in Examples 1 to 5, it was found that the core-shell type resin binder according to the present invention can provide a skin material in which wrinkles are less likely to occur due to the fixing of constituent fibers to each other. In addition, the skin materials prepared in Examples 1 to 5 were all prevented from generating fluff.

[0104] (Example 6) A non-woven fabric was prepared in the same manner as in Example 2, except that binder liquid D1 was used instead of binder liquid A2. The non-woven fabric thus prepared was used as the skin material.

[0105] (Example 7) A non-woven fabric was prepared in the same manner as in Example 2, except that binder liquid D2 was used instead of binder liquid A2. The non-woven fabric thus prepared was used as the skin material.

[0106] (Example 8) A non-woven fabric was prepared in the same manner as in Example 4, except that binder liquid D2 was used instead of binder liquid A2. The non-woven fabric thus prepared was used as the skin material.

[0107] (Example 9) A non-woven fabric was prepared in the same manner as in Example 4, except that binder liquid D3 was used instead of binder liquid A2. The non-woven fabric thus prepared was used as the skin material.

[0108] Note that in the non-woven fabrics prepared in Examples 6 to 9, aggregates formed by the aggregation of the core-shell type resin binder covered the constituent fibers of the non-woven fabric, and a plurality of constituent fibers were tied and fixed by the aggregates. Furthermore, the constituent fibers were also adhered and fixed by the cured thermosetting resin.

[0109] The various components of the skin material (non-woven fabric) prepared as described above are summarized in Table 5. For components that are not present, a "-" mark is described in the table.

[0110]

Table 5

[0111] For each of the skin materials prepared in Examples 6 to 9, the evaluation results of the presence or absence of wrinkles due to thermoforming and the presence or absence of fuzz on the main surface were confirmed by the above-described method, and the evaluation results are summarized in Table 6.

[0112]

Table 6

[0113] From the results of confirming the presence or absence of wrinkles due to thermoforming for the skin materials prepared in Examples 6 to 9, it was found that the core-shell type resin binder according to the present invention can provide a skin material in which the constituent fibers are fixed to each other, and thus wrinkles are less likely to occur due to thermoforming. In addition, the skin materials prepared in Examples 6 to 9 were found to prevent the occurrence of fuzz.

Industrial Applicability

[0114] According to the present invention, it is possible to provide a skin material capable of preparing various interior materials and vehicle insulator materials. In particular, it is possible to provide a skin material capable of preparing ceiling materials for vehicles such as automobiles, pillar garnishes, doors, instrument panels, steering wheels, shift levers, console boxes, tonneau covers, luggage floors, luggage sides, floor insulator materials, trunk trim materials, dash insulator materials, etc.

Claims

1. A skin material comprising a fabric in which constituent fibers are fixed by a core-shell type resin binder, wherein the resin of the shell portion and the resin of the core portion are different types of resins. Skin material.

2. The skin material according to claim 1, wherein the constituent fibers are also fixed by a thermosetting resin.

3. A method for manufacturing a skin material, comprising: (Step 1) preparing a fabric; (Step 2) preparing a core-shell type resin binder composed of different types of resins for the shell portion and the core portion; (Step 3) preparing a binder liquid in which the core-shell type resin binder is dispersed in a dispersion medium; (Step 4) applying the binder liquid to the fabric; (Step 5) removing the dispersion medium by supplying the fabric to which the binder liquid has been applied to a heating device; (Step 6) allowing to cool or cooling after supplying to the heating device. A method for manufacturing a skin material, comprising a fabric in which constituent fibers are fixed by the core-shell type resin binder. ​ ​

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