JP6555894B2 - Skin material for vehicle interior - Google Patents

Description

  The present invention relates to a vehicle interior skin material that can be suitably used as, for example, a vehicle instrument panel or a door skin material.

  Conventional skin materials include vinyl chloride leather, synthetic leather, artificial leather, and natural leather with a resin layer on a fibrous base material. Susceptible to outside temperature. Therefore, when exposed to extreme temperatures, the skin material itself becomes excessively hot or cold, and when the skin material comes into contact with the skin, it gives a sudden temperature change to the skin, causing discomfort. To remember. In particular, when it is used in a space such as a vehicle interior material that is affected by the outside air temperature, it becomes a significant problem.

  In order to solve such a problem, the inventors have sequentially laminated a porous heat insulating layer, a colored layer, and a protective layer on a fibrous base material as in Patent Document 1, and contact the surface of the skin material. A skin material is disclosed in which contact cold / warm feeling is reduced by providing irregularities with an area ratio of 65% or less.

Japanese Patent No. 5496389

  In the configuration disclosed in Patent Document 1, although it is possible to improve the feeling of contact cooling / heating, in applications where elongation characteristics are required when molding a skin material, such as an instrument panel or a door of a vehicle, It turns out that there is a problem. That is, in these applications, a forming process by thermoforming such as vacuum forming may be performed to give a predetermined three-dimensional shape to the skin material. At that time, the skin material cannot follow the molding surface of the mold having a complicated three-dimensional shape, and the surface of the processed material may have wrinkles or distortions on the surface of the processed product. .

  The present invention has been made in view of the above points, and provides a vehicle interior skin material that can be used in a state in which sticking is good even in applications where elongation characteristics are required during molding processing. The purpose is to do.

  A skin material for vehicle interior according to the present invention includes a porous heat insulating layer and a colored layer laminated on the porous heat insulating layer, and the skin material is stretched at 50% under a condition of 150 ° C. It is the skin material for vehicle interiors whose tensile strength which is the tensile force per unit width is 0.20-12.00 N / cm.

  According to the present invention, for vehicle interiors that can be used in a state in which sticking is good, such as an instrument panel or a door of a vehicle, even in applications where elongation characteristics are required at the time of molding of the skin material. A skin material can be provided.

It is a cross-sectional schematic diagram of the skin material for vehicle interior which concerns on one Embodiment. It is a cross-sectional schematic diagram of the skin material for vehicle interior which concerns on other embodiment.

  The skin material according to the present embodiment is a skin material suitable for vehicle interior panels or doors for vehicle interiors, particularly for vehicle interior panels that are molded and used, and at least a porous heat insulating layer. A skin material obtained by sequentially laminating a colored layer, wherein the skin material has a tensile strength at 50% elongation under a condition of 150 ° C. of 0.20 to 12.00 N / cm.

  It is essential that the skin material of this embodiment has a tensile strength at 50% elongation of 150 ° C. at 0.20 to 12.00 N / cm, and the tensile strength is 0.20 to 6.00 N / cm. And more preferably 0.30 to 3.50 N / cm. By having such elongation characteristics, the skin material follows the mold with a complicated three-dimensional shape when the skin material is molded by thermoforming such as vacuum forming when it is placed on the instrument panel or door. Since it is easy to suppress, and it can suppress that the wrinkles and distortion of a skin material remain on the surface of a processed product, it can be set as a skin material with good sticking.

  The tensile strength is a tensile force per unit width (1 cm) when the skin material is stretched 50% under a condition of 150 ° C., and is measured as follows.

  As an apparatus used for the measurement, a tensile tester (“Shimadzu Autograph AG-IS” manufactured by Shimadzu Corporation) capable of measuring while adjusting the temperature of the test piece of the skin material to 150 ° C. is used. The skin material is cut into a width of 30 mm and a length of 150 mm to obtain a test piece, the grip interval of the tensile tester is adjusted to 100 mm, and the test piece is fixed. Under a measurement environment of 150 ° C., the grip width is 30 mm, the tensile speed is 100 mm / A tensile test is performed at min. The tensile force (N / cm) at 50% elongation is calculated by taking the tensile force (N) when the grip interval is 150 mm as a measured value and dividing by the width of the test piece (0.3 cm).

  FIG. 1 schematically shows a cross-sectional structure of a skin material 1 according to an embodiment. The skin material 1 includes a porous heat insulating layer 2 and a colored layer 3 laminated on the porous heat insulating layer 2. In the illustrated example, a protective layer 4 is laminated on the colored layer 3, and unevenness (that is, a bumpy pattern) is provided on the front surface 5 of the skin material 1. However, it is an aspect which does not have a base material like FIG.

  FIG. 2 schematically shows a cross-sectional structure of a skin material 1A according to another embodiment. In this skin material 1A, a base material 6 is laminated on the back surface of the porous heat insulating layer 2 (the surface opposite to the colored layer 3). That is, in the skin material 1A, the porous heat insulating layer 2 and the colored layer 3 are sequentially laminated on one surface of the substrate 6. In the illustrated example, the protective layer 4 is laminated on the colored layer 3, and the unevenness is provided on the front surface 5 of the skin material 1 </ b> A.

  The porous heat insulating layer in the present embodiment is a heat insulating layer having a large number of closed holes (that is, closed holes that do not penetrate). By being porous, it becomes difficult for heat to be transmitted, the skin material is not easily affected by the outside air temperature, and a skin material with a low feeling of contact cooling / heating can be obtained.

  It is preferable that the softening temperature of a porous heat insulation layer is 110-250 degreeC, More preferably, it is 130-220 degreeC, More preferably, it is 130-180 degreeC. Since the porous heat insulation layer has such a softening temperature, it is easy to set the tensile strength at 50% elongation under the condition of 150 ° C. within the above range, and to form a complicated three-dimensional shape when molding the skin material. Followability can be improved. In addition, since the softening temperature of the porous heat insulating layer is 110 ° C. or higher, it is possible to prevent clogging of clogging holes even when exposed to high temperatures during molding processing. The effect of maintaining the feeling of cold contact temperature even after molding can be enhanced, and deformation of the appearance can be suppressed. When the softening temperature is 250 ° C. or less, the texture and bending resistance of the obtained skin material can be improved.

  The softening temperature of the porous heat insulating layer is measured by a method based on JIS K7196. In the examples described later, a thermomechanical analyzer (model EXSTAR TMA-SS6100, manufactured by Hitachi High-Tech Science Co., Ltd.) is used as a testing machine, and an indenter having a needle-in probe shape and a needle tip diameter of 1.0 mm is used. did.

  The shape of the closed hole in the porous heat insulating layer is not particularly limited and may be an indefinite shape, but it is true from the viewpoint that the shape change due to the expansion and contraction of the closed hole is difficult due to the high temperature treatment during the molding of the skin material. It is preferably spherical. Moreover, the magnitude | size of an obstruction | occlusion hole is not specifically limited, For example, it is preferable that the long diameter of an obstruction | occlusion hole is the range of 10-200 micrometers, More preferably, it is the range of 15-100 micrometers. When the major axis is 10 μm or more, the effect of the contact cold / warm feeling can be enhanced. Moreover, when the major axis is 200 μm or less, it is possible to ensure the stability of the shape of the closed hole of the porous heat insulating layer by the high temperature treatment during the molding process.

  The closed pore area ratio of the porous heat insulating layer, that is, the proportion of the closed holes in the vertical cross section of the porous heat insulating layer is not particularly limited, and is preferably, for example, 75 to 95%, more preferably 80 to 90%. It is. When the obstruction hole area ratio is 75% or more, the effect of the contact cold / warm feeling can be enhanced. When the blocking hole area ratio is 95% or less, it is possible to prevent the durability, in particular, the wear resistance, the bending resistance, the tensile strength, and the tear strength from being impaired.

  As a method for calculating the area ratio of the closed hole, the area ratio of the closed hole part to the area occupied by the entire porous heat insulating layer of the vertical section is obtained by observing the vertical section of the layer with an electron microscope, a microscope, etc. It is.

  The means for forming a large number of closed holes in the porous heat insulating layer is not particularly limited, and a known method can be adopted. Examples thereof include physical foaming by mechanical stirring, chemical foaming by adding a foaming agent, and formation of closed pores by adding hollow fine particles. Alternatively, the pores may be formed by coating the surface of the layer with a nonporous layer after the formation of the pores by wet coating of polyurethane resin. Preferably, from the viewpoint of easy adjustment of the shape and size of the closed hole and the area ratio of the closed hole, the closed hole is formed by adding hollow fine particles. That is, in one embodiment, the porous heat insulating layer is formed by blending hollow fine particles with a resin that is a matrix (that is, a base material or a main agent), and contains a large number of hollow fine particles in the porous heat insulating layer. It is preferable that a large number of closed holes are formed by the hollow fine particles.

  The hollow fine particles refer to spherical shapes in which minute voids inside are covered with coatings (called outer shells, outer walls, etc.) made of various materials. In particular, it is preferable that no volume expansion occurs even when heat treatment is performed. By using such hollow fine particles, it is possible to minimize the volume fluctuation of the porous heat insulating layer at the time of manufacture, reduce the variation in quality, and the resin around the hollow fine particles is stretched and thinned. Can be prevented, and the appearance, texture, and wear resistance can be made good.

  As the hollow fine particles, various particles satisfying the above conditions can be used. Examples thereof include organic hollow fine particles having an outer shell made of a thermosetting resin such as a phenol resin, an epoxy resin or a urea resin, or a thermoplastic resin such as an acrylic resin or a vinyl chloride resin. Alternatively, inorganic hollow fine particles having an outer shell made of glass, shirasu, silica, alumina, carbon or the like can also be mentioned. Moreover, what coat | covered the surface of organic hollow fine particles with inorganic fine powders, such as a calcium carbonate, a talc, or a titanium oxide, can also be used. Among these, from the viewpoint of heat resistance, wear resistance, and strength, organic hollow fine particles having an outer shell made of a thermoplastic resin, or organic hollow fine particles whose surface is coated with an inorganic fine powder are preferable.

  Here, the hollow fine particles having an outer shell made of a thermoplastic resin that is preferably used are typically those obtained by previously foaming a microcapsule type foaming agent. The microcapsule-type foaming agent itself encloses a volatile foaming agent such as a low-boiling point hydrocarbon in an outer shell made of a thermoplastic resin that can be softened and expanded by heat treatment. In addition, it can be used as an already foamed material obtained by foaming in advance.

  The glass transition point (Tg) of the thermoplastic resin forming the outer shell is preferably 50 to 150 ° C., more preferably 60 to 90 ° C. from the viewpoint of heat resistance. When the glass transition point of the thermoplastic resin is 50 ° C. or higher, the hollow fine particles are prevented from being crushed during the molding process of the skin material, and the effect of improving the feeling of contact cooling / warming can be maintained. In addition, when the glass transition point is 150 ° C. or lower, the outer shell of the hollow fine particles at the time of molding of the skin material is appropriately deformed, thereby enabling pattern transfer following the fine shape of the mold. Become.

  Moreover, it is preferable that the softening temperature of the thermoplastic resin which forms an outer shell is 110-250 degreeC, More preferably, it is 130-220 degreeC. By satisfying this, even when exposed to high temperatures during molding of the skin material, excessive deformation of the outer shell of the hollow fine particles is suppressed, and as a result, the clogged pores of the porous heat insulating layer are less likely to be crushed. The holding effect can be enhanced.

  Here, the glass transition point and the softening temperature of the thermoplastic resin forming the outer shell are measured as follows. The glass transition point was measured by a method based on JIS K7121, and in the examples described later, a high-sensitivity differential scanning calorimeter (model EXSTAR-DSC6200, manufactured by Hitachi High-Tech Science Co., Ltd.) was used as a tester. As the softening temperature, a thermomechanical analyzer (model TMA2940, manufactured by TA instruments) is used as a tester, and 250 μg of hollow fine particles (in the case of thermal expansion, those in an already foamed state) are 7 mm in diameter and depth. Place in a 1 mm aluminum cup and continuously apply the vertical displacement of the applied indenter when heated from 80 ° C to 300 ° C at a heating rate of 5 ° C / min with a force of 0.1 N applied from above. The temperature at which the maximum displacement was measured was defined as the softening temperature of the outer shell of the hollow fine particles.

  In the present embodiment, such hollow fine particles can be used singly or in combination of two or more.

  Resins used as the main agent in the porous heat insulating layer, that is, the resin serving as a matrix include, for example, polyurethane resins, polyamino acid resins, vinyl chloride resins, SBR resins, NBR resins, acrylic resins, polyester resins, and copolymers thereof. Well-known synthetic resins can be mentioned, and these can be used alone or in combination of two or more. Among these, it is preferable to select a polyurethane resin or a copolymer thereof, or a mixed resin containing polyurethane resin as a main component (collectively referred to as a polyurethane resin) from the viewpoint of wear resistance, texture, and the like. A polyurethane resin is more preferable. The type of resin is not particularly limited, such as a solventless system, a solvent system, and an aqueous system.

  The glass transition point (Tg) of the matrix is preferably −100 to 50 ° C., more preferably −70 to −10 ° C. When the glass transition point is −100 ° C. or higher, the heat resistance is improved, and even when exposed to a high temperature during molding of the skin material, the clogging of the closed hole can be prevented, so that the effect of maintaining a cold feeling of contact is enhanced. And deterioration of appearance can be suppressed. When the glass transition point is 50 ° C. or lower, it is possible to obtain a skin material having a soft texture and excellent bending resistance. Here, the matrix is a portion of the porous heat insulating layer excluding the hollow fine particles, and is composed of the main agent and additives such as a crosslinking agent and a leveling agent as optional components.

  The softening temperature of the matrix is preferably 110 to 250 ° C, more preferably 130 to 220 ° C. By satisfy | filling this, it is easy to set the softening temperature of a porous heat insulation layer in the range of 110-250 degreeC.

  Here, the glass transition point and softening temperature of the matrix are measured as follows. The glass transition point was measured by a method based on JIS K7121, and in the examples described later, a high-sensitivity differential scanning calorimeter (model EXSTAR-DSC6200, manufactured by Hitachi High-Tech Science Co., Ltd.) was used as a tester. The softening temperature is measured by a method according to JIS K7196. In the examples described later, a thermomechanical analyzer (model EXSTAR TMA-SS6100, manufactured by Hitachi High-Tech Science Co., Ltd.) is used as a tester, and the indenter has a needle shape. An input probe having a needle tip diameter of 1.0 mm was used.

  For the porous heat insulating layer, additives such as a crosslinking agent, a leveling agent, a pigment, and a matting agent can be used.

  The thickness of a porous heat insulation layer is not specifically limited, For example, it is preferable that it is 20-300 micrometers, More preferably, it is 50-200 micrometers, More preferably, it is 100-200 micrometers. When the thickness is 20 μm or more, it is possible to transfer the pattern following the fine shape of the mold during the molding of the skin material, and to enhance the effect of improving the feeling of contact cold / warm. Moreover, the fall of a texture can be suppressed because thickness is 300 micrometers or less. The thickness of the porous heat insulating layer is preferably larger than the thickness of the colored layer and larger than the total thickness of the colored layer and the protective layer.

  The porous heat-insulating layer preferably has a tensile strength at 50% elongation at 150 ° C. of 0.10 to 6.00 N / cm, more preferably 0.20 to 3.00 N / cm. It may be 20 to 1.00 cm / N. When the tensile strength of the porous heat insulating layer is 0.10 N / cm or more, the mold transfer effect by molding can be enhanced while keeping the thickness of the porous heat insulating layer uniform even during the molding process. When the tensile strength is 6.00 N / cm or less, the formability along the mold can be improved by extending the skin material during the molding process.

  The tensile strength of the porous heat insulating layer is a tensile force per unit width at 50% elongation under 150 ° C., and is measured as follows. A film of a porous heat insulation layer having a thickness corresponding to the thickness of the skin material is prepared, and the film is cut into a width of 30 mm and a length of 150 mm to obtain a test piece. Using a tensile tester (Shimadzu Autograph AG-IS, manufactured by Shimadzu Corporation) that can be measured while adjusting the temperature to 150 ° C, the gripping interval is adjusted to 100 mm, and the test piece is fixed, and the measurement environment at 150 ° C Below, a tensile test is performed at a grip width of 30 mm and a tensile speed of 100 mm / min. The tensile force (N / cm) at 50% elongation is calculated by taking the tensile force (N) when the grip interval is 150 mm as a measured value and dividing by the width of the test piece (0.3 cm).

  The colored layer in the present embodiment is a layer for concealing the porous heat insulating layer and coloring it in a desired color.

  As resin which comprises a colored layer, resin similar to the main ingredient of a porous heat insulation layer can be used. Among these, from the viewpoints of versatility, wear resistance, texture, etc., polyurethane resins and their copolymers, or mixtures containing polyurethane resins as a main component (collectively referred to as polyurethane resins) are preferred, and polycarbonate polyurethanes. More preferred is a resin. The type of resin is not particularly limited, such as a solventless system, a solvent system, or an aqueous system.

  An inorganic pigment and an organic pigment are added to the colored layer as a colorant. The addition amount of the pigment is not particularly limited, and for example, it is preferably 1 to 20% by mass, more preferably 5 to 15% by mass in terms of solid content. When the addition amount is 1% by mass or more, even when the thickness of the colored layer becomes thin due to elongation by molding, the concealability can be ensured and the design can be maintained. Moreover, by being 20 mass% or less, friction fastness is not impaired.

  In addition to the pigment, a known additive such as a filler, a smoothing agent, a cross-linking agent, a matting agent, and a leveling agent can be used for the colored layer, if necessary. Especially, it is preferable to use a filler from a viewpoint that the elongation characteristic of the film obtained is improved. Examples of the filler include silica, alumina, resin beads such as urethane resin and acrylic resin.

  The thickness of a colored layer is not specifically limited, For example, 1-100 micrometers is preferable, More preferably, it is 5-40 micrometers. When the thickness is 1 μm or more, the wear resistance can be improved, and the concealability of the porous heat insulating layer and the sufficient colorability as a design are enhanced even if the thickness is reduced by elongation in the molding process. be able to. When the thickness is 100 μm or less, the effect of improving the feeling of contact cold / warm can be enhanced.

  The colored layer preferably has a tensile strength at 50% elongation under the condition of 150 ° C. of 0.10 to 6.00 N / cm, more preferably 0.20 to 3.00 N / cm, and 0.20. It may be ˜1.00 cm / N. When the tensile strength of the colored layer is 0.10 N / cm or more, the mold transfer effect by molding can be enhanced while keeping the thickness of the colored layer uniform even during the molding process. When the tensile strength is 6.00 N / cm or less, the formability along the mold can be improved by extending the skin material during the molding process.

  The tensile strength of the colored layer is a tensile force per unit width at 50% elongation under the condition of 150 ° C., and is measured as follows. A single colored layer film having a thickness corresponding to the thickness of the skin material is prepared, and the film is cut into a width of 30 mm and a length of 150 mm to obtain a test piece. Using a tensile tester (Shimadzu Autograph AG-IS, manufactured by Shimadzu Corporation) that can be measured while adjusting the temperature to 150 ° C, the gripping interval is adjusted to 100 mm, and the test piece is fixed, and the measurement environment at 150 ° C Below, a tensile test is performed at a grip width of 30 mm and a tensile speed of 100 mm / min. The tensile force (N / cm) at 50% elongation is calculated by taking the tensile force (N) when the grip interval is 150 mm as a measured value and dividing by the width of the test piece (0.3 cm).

  In the skin material according to this embodiment, a base material may be laminated on the back surface (the surface opposite to the colored layer) of the porous heat insulating layer as long as the elongation characteristics are not impaired. Examples of the substrate include a fibrous substrate and a foamed sheet.

  Examples of the fibrous base material include fabrics such as woven fabrics, knitted fabrics and nonwoven fabrics, and natural leather. As the fabric, a known solvent-based or water-based polymer compound, for example, a polyurethane resin or a copolymer thereof coated or impregnated and dry-coagulated or wet-coagulated can be used. The kind of fiber is not particularly limited, and known fibers such as natural fibers, regenerated fibers, semi-synthetic fibers, and synthetic fibers can be used, and two or more of these fibers may be used in combination. Among these, synthetic fibers, particularly polyester fibers are preferable from the viewpoint of strength and workability. The fibrous base material may be colored with a dye or a pigment.

  Examples of the foam sheet include foam sheets made of polypropylene resin, polyethylene resin, and polyurethane resin. Preferably, from the viewpoint of moldability, a foamed sheet made of polypropylene resin or polyethylene resin is preferable.

  The thickness of the base material is not particularly limited, and is preferably in the range of 0.2 to 20 mm, for example, more preferably in the range of 0.2 to 10 mm, and still more preferably in the range of 0.5 to 2 mm. . When the thickness is 0.2 mm or more, the effect of improving the feeling of contact cooling / warminess can be enhanced due to being hardly affected by the outside air temperature, and the merchantability can be enhanced as a voluminous texture. When the thickness is 20 mm or less, it is easy to obtain a uniform finish (good appearance) by suppressing the lifting of the uneven shape during the molding process.

The specific gravity of the substrate is not particularly limited, for example, is preferably 0.005~0.1g / cm ^3, more preferably from 0.01 to 0.05 g / cm ^3. When the specific gravity is 0.005 g / cm ³ or more, it is less affected by the outside air temperature and can improve the effect of improving the feeling of contact cooling / warming, and the breaking strength, tearing strength and texture may be impaired. Can be prevented. In addition, when the specific gravity is 0.1 g / cm ³ or less, it is possible to prevent a feeling of heat when touching in a high temperature environment or damage to the texture.

  The base material preferably has a tensile strength at 50% elongation under the condition of 150 ° C. of 0.10 to 11.80 N / cm, more preferably 0.20 to 5.00 N / cm. When the tensile strength of the substrate is 0.10 N / cm or more, the mold transfer effect by molding can be enhanced while keeping the thickness of the substrate uniform even during the molding process. When the tensile strength is 11.80 N / cm or less, the formability along the mold can be improved by extending the skin material during the molding process.

  The tensile strength of the substrate is a tensile force per unit width at 50% elongation under 150 ° C., and is measured as follows. A tensile tester (Shimadzu Corporation) that can measure while adjusting the temperature to 150 ° C by cutting a base material having a thickness corresponding to the layer thickness when it is made into a skin material into a test piece by cutting it to a width of 30 mm and a length of 150 mm. Using “Shimadzu Autograph AG-IS”), adjusting the grip interval to 100 mm, fixing the test piece, and performing a tensile test at a grip width of 30 mm and a pulling speed of 100 mm / min in a measurement environment at 150 ° C. . The tensile force (N / cm) at 50% elongation is calculated by taking the tensile force (N) when the grip interval is 150 mm as a measured value and dividing by the width of the test piece (0.3 cm).

  The skin material according to the present embodiment may be further provided with a protective layer on the colored layer from the viewpoint of wear resistance.

  As resin which comprises a protective layer, resin similar to a porous heat insulation layer can be used. Among these, from the viewpoint of wear resistance, texture and the like, a polyurethane resin, a copolymer thereof, or a mixture containing polyurethane resin as a main component (collectively referred to as a polyurethane resin) is preferable, and a polycarbonate polyurethane resin is more preferable. preferable. The type of resin is not particularly limited, such as a solventless system, a solvent system, and an aqueous system.

  The thickness of a protective layer is not specifically limited, For example, it is preferable that it is 1-50 micrometers, More preferably, it is 5-20 micrometers. Abrasion resistance can be improved because thickness is 1 micrometer or more. When the thickness is 50 μm or less, it is possible to suppress a decrease in the effect of improving the contact cold / warm feeling.

  The total thickness of the colored layer and the protective layer is not particularly limited, but is preferably 2 to 150 μm, more preferably 10 to 60 μm, and further preferably 20 to 50 μm from the viewpoint of the feeling of contact cooling / heating. There may be. When the total thickness is 2 μm or more, the wear resistance can be improved. Moreover, the fall of the improvement effect of a contact cold / warm feeling can be suppressed because the sum total of thickness is 150 micrometers or less.

  The skin material according to the present embodiment preferably has irregularities on its front surface. Moreover, it is preferable that the contact area ratio in the front surface of a skin material is 65% or less by an unevenness | corrugation. Here, the front surface of the skin material is a design surface that appears on the front side (vehicle interior side) when the skin material is used as a skin material for an instrument panel, a door, etc. It is a possible surface.

  The contact area ratio on the front surface is a value obtained by simply calculating the ratio of the area where the skin adheres to the front surface of the skin material when a person touches the skin material by a method described later. Generally, based on the fact that the skin is considered to be in close contact with the deep part from the top of the convex part to 50 μm when the uneven surface is touched, the contact area ratio on the front surface of the skin material is calculated by the following method.

  On the front surface of the skin material, a rectangular area of 2.5 mm in length and 2.0 mm in width is randomly extracted, and the depth at every XY coordinate of 10 μm is measured using a laser microscope. The ratio of the number of XY coordinates indicating the depth from the top of the highest convex portion existing in the region (that is, the highest point in the region) to 50 μm with respect to the total number of XY coordinates on the front surface of the skin material The contact area ratio. Extraction of the region is performed at 10 random locations, and the average value of the contact area ratios calculated at these 10 locations is defined as the contact area ratio on the front surface of the skin material.

  When the contact area ratio on the front surface of the skin material calculated in this way is 65% or less, even when exposed to an extreme temperature, it is not easily affected. There is little rapid heat transfer. Therefore, it is possible to provide a skin material that is less susceptible to temperature change and has a low feeling of contact cooling / heating. The contact area ratio is preferably 40% or less. On the other hand, the contact area ratio is preferably 5% or more from the viewpoint of design. More preferably, the contact area ratio is 10% or more, and more preferably 20% or more. In one embodiment, the contact area percentage may be 30-50%.

  In addition, an unevenness | corrugation can be formed in the front surface of a skin material by providing a recessed part, providing a convex part, providing a recessed part and a convex part in combination. Examples of the method for forming irregularities include a method of applying a resin to a releasable substrate having an irregular pattern and a method by embossing.

  Lamination of each layer of skin material is performed by the following method, for example. (A) After applying the resin liquid for forming the colored layer to the releasable substrate, dry-solidifying to form the colored layer, and then applying the resin liquid for forming the porous heat insulating layer on the colored layer Then, it is dry-solidified to form a colored layer and a porous heat insulating layer on the releasable substrate. As another method, (B) after applying the resin liquid for forming the porous heat insulating layer to the releasable substrate, the porous heat insulating layer is formed by dry solidification, and then on the porous heat insulating layer, After applying the resin liquid for forming the colored layer, it is dry-solidified to form a porous heat insulating layer and a colored layer on the releasable substrate.

  Moreover, when laminating | stacking base materials, such as a fibrous base material and a foam sheet, as mentioned above on the back surface of a porous heat insulation layer, it is performed with the following method, for example. (C) After applying the resin liquid for forming the porous heat insulating layer on one side of the base material and then dry-solidifying it, the porous heat insulating layer is laminated on the base material, and then the resin liquid for forming the colored layer is porous heat insulating After coating on the layer, it is dry-solidified to form a colored layer on the porous heat insulating layer. As another method, (D) a resin layer forming a colored layer is applied to a releasable substrate, and then dry-solidified to form a colored layer, and then a porous heat insulating layer is formed on the colored layer. After applying the resin liquid, while having adhesiveness, the porous heat insulating layer is formed between the base material and the colored layer by pressure-bonding it to one side of the base material. As another method, (E) a colored liquid layer is formed by applying a resin liquid for forming a colored layer to a releasable substrate, followed by dry solidification, and then forming a porous heat insulating layer on the colored layer. After applying the resin liquid, it is dry-solidified to form a colored layer and a porous heat insulating layer on the releasable substrate. Next, the porous heat insulation layer and the colored layer are laminated via the adhesive layer by bonding the porous heat insulation layer and the substrate with an adhesive.

  When providing a protective layer, the lamination | stacking is performed by the following method, for example. After laminating the (base material) porous insulating layer and the colored layer by the methods (A) to (E) above, a resin solution for forming a protective layer is applied on the colored layer and then dry-solidified to protect it. Form a layer. Here, a resin liquid for forming a protective layer on a colored layer after the formation of the colored layer and before the embossing when the unevenness is imparted to the front surface of the skin material by the embossing. May be applied and dried to solidify to form a protective layer, and then an uneven pattern may be formed on the front side by embossing. In addition, when unevenness is imparted by a releasable substrate having a concavo-convex pattern, a colored liquid layer is first formed on a releasable substrate by first applying a resin liquid for forming a protective layer and dry-solidifying to form a protective layer. A colored layer may be formed by applying a resin solution for forming a film. Alternatively, the protective layer may be formed by applying a resin solution for forming a protective layer on the colored layer and then solidifying and drying the colored layer using a releasable base material having an uneven pattern. .

  In addition, the coating method of each resin liquid includes well-known methods, such as knife coating, roll coating, gravure coating, or spray coating.

  The layer that becomes the outermost surface of the skin material according to the present embodiment (specifically, the protective layer when a protective layer is provided, and the colored layer when a protective layer is not provided) is not porous, that is It is preferably porous. This is because if the outermost surface layer is nonporous, it is advantageous in terms of wear resistance.

  The skin material targeted by the present embodiment is a porous heat insulating layer and a colored layer as essential constituent members, but if necessary, one layer or two or more layers are provided between each layer. You may have.

  The use of the skin material according to the present embodiment includes vehicle interior materials such as automobile interior materials, particularly instrument panel skins and door lining materials that are subjected to molding by thermoforming such as vacuum forming. Can be suitably used.

[Example 1]
[Formulation 1 (for colored layer)]
Main agent: water-based polycarbonate-based polyurethane resin (manufactured by Bayer Co., Ltd., Bihydrol UH2952, solid content 40% by mass): 90 parts by mass Filler-containing main agent: silica-based water-based polycarbonate-based polyurethane resin (manufactured by LANXESS Co., Ltd., HYDRHOLAC UD-2, solid 25 parts by mass): 10 parts by mass Crosslinking agent: Isocyanate-based crosslinking agent (manufactured by Bayer Co., Ltd., Bihijoule 3100, solid content 100% by mass): 1 part by mass Pigment: Carbon black black pigment (manufactured by LANXESS Co., Ltd., EUDERM Black) BN, solid content 25% by mass): 20 parts by mass Water: 20 parts by mass Leveling agent: Silicone leveling agent (manufactured by LANXESS, AQUADERM Fluid H, solid content 100% by mass): 1 part by mass Preparation method: viscosity The , 000cps (B type viscometer, rotor: No4,12rpm, 23 ℃) was prepared. The tensile strength at the time of 50% elongation at 150 ° C. of the film (thickness = 30 μm) prepared with the prepared coating material was 0.32 N / cm.

[Formulation 2 (for porous heat insulating layer)]
Main agent: Water-based polycarbonate-based polyurethane resin (manufactured by Bayer Co., Ltd., Bihydrol UH2952, solid content 40% by mass): 100 parts by mass Hollow fine particles: Microfoamed microcapsules (manufactured by Matsumoto Yushi Seiyaku Co., Ltd., Matsumoto Microsphere FN-100S (by heat treatment) Used in an already foamed state), average particle size 50 μm, solid content 100% by mass, powder, outer shell: acrylonitrile-based polymer (softening temperature: 150 ° C., Tg: 70 ° C.), inclusion: isopentane, already foamed product) : 2.5 parts by mass Crosslinking agent: Isocyanate-based crosslinking agent (manufactured by Bayer Co., Ltd., Bihijoule 3100, solid content 100% by mass): 1 part by mass Leveling agent: Silicone-based leveling agent (manufactured by LANXESS, AQUADERM Fluid H, solid Min 100% by weight): 1 part by weight water 20 parts by mass Preparation method: The viscosity 5,000 cps (B-type viscometer, rotor: No4,12rpm, 23 ℃) was prepared. The tensile strength at the time of 50% elongation at 150 ° C. of a film (thickness = 150 μm) prepared with the prepared coating material was 0.31 N / cm. The softening temperature of the film produced with the prepared paint was 150 ° C. Moreover, the softening temperature (namely, the softening temperature of a matrix) of the film produced by the formulation which remove | excluded hollow microparticles from the formulation 2 was 175 degreeC, and Tg was -60 degreeC.

[Formulation 3 (for protective layer)]
Main agent: water-based polycarbonate-based polyurethane resin (BAYDERM Finish 61UD solid content 35% by mass): 90 parts by mass Filler-containing main agent: silica-based water-based polycarbonate-based polyurethane resin (HYDRHOLAC UD-2, solid content 25% by mass): 10 parts by mass Cross-linking Agent: Isocyanate-based crosslinking agent (AQUADERM XL-50, solid content 50 mass%): 1 mass part Leveling agent: Silicone-based leveling agent (AQUADERM Fluid H, solid content 100 mass%): 1 mass part Water: 20 mass parts Raw material Are all manufactured by LANXESS, except for water.
Preparation method: The viscosity was adjusted to 200 cps (B-type viscometer, rotor: No. 1, 12 rpm, 23 ° C.).

  The polyurethane resin composition for the colored layer prepared according to the above-mentioned prescription 1 is applied to release paper having a grainy uneven pattern (AR-96M, manufactured by Asahi Roll Co., Ltd.) with an average coating thickness of 100 μm using a comma coater. Thus, it apply | coated to the sheet form, and it processed for 3 minutes at 100 degreeC with the dryer, and formed the colored layer. Next, the polyurethane resin composition for a porous heat insulation layer prepared according to the above-mentioned prescription 2 is applied to the surface of the colored layer formed on the release paper with a comma coater so as to have an average coating thickness of 300 μm. And it processed for 3 minutes at 100 degreeC with the dryer, and formed the porous heat insulation layer. The thickness of the layer was 30 μm for the colored layer and 150 μm for the porous heat insulating layer. The size (major axis) of the closed hole in the porous heat insulating layer was 50 μm, and the closed hole area ratio was 90%.

  The resulting laminate of the colored layer and the porous heat insulating layer was preliminarily dried by heat treatment at 100 ° C. for 1 minute, and then aged at 40 ° C. for 12 hours, and then the release paper was peeled off. Subsequently, the polyurethane resin composition for the protective layer prepared according to the above-mentioned prescription 3 was applied to the surface of the colored layer after the release paper was peeled off, using a reverse coater so as to have an average thickness of 50 μm, and then dried. A protective layer having a thickness of 10 μm was formed by processing at 100 ° C. for 3 minutes using a machine, and the skin material of Example 1 was obtained.

[Examples 2-6, 9-16 and Comparative Examples 1-2]
The skin materials of Examples 2 to 6, 9 to 16 and Comparative Examples 1 to 2 were produced in the same manner as Example 1 except that the prescriptions of the colored layer and the porous heat insulating layer were as shown in Table 1. The raw materials in Table 1 are as follows.
Main agent: BAYDERM Bottom DLV (manufactured by LANXESS Corporation, water-based polycarbonate polyurethane resin, solid content 40% by mass)
Main agent: BAYDERM 51UD (manufactured by LANXESS, water-based ether-based polyurethane resin, solid content 35% by mass)
Main agent: LCC Binder UB-1770 (manufactured by DIC Corporation, water-based polycarbonate polyurethane resin, solid content 30% by mass)
Hollow fine particles: F-30 already foamed product (Matsumoto Yushi Seiyaku Co., Ltd., Matsumoto Microsphere F-30 (used in a foamed state by heat treatment), average particle size 50 μm, solid content 100% by mass, outer shell: Vinyl chloride-acrylonitrile polymer (softening temperature: 100 ° C., Tg: 20 ° C., inclusion: isopentane)
Hollow fine particles: F-48 pre-foamed product (Matsumoto Yushi Seiyaku Co., Ltd., Matsumoto Microsphere F-48 (used in a pre-foamed state by heat treatment), average particle size 50 μm, solid content 100% by mass, outer shell: Acrylonitrile polymer (softening temperature: 120 ° C, Tg: 50 ° C), inclusion: isopentane)
Hollow fine particles: F-2800D pre-foamed product (Matsumoto Yushi Seiyaku Co., Ltd., Matsumoto Microsphere F-2800D (used in a pre-foamed state by heat treatment), average particle size 50 μm, solid content 100% by mass, outer shell: Acrylonitrile polymer (softening temperature: 245 ° C., Tg: 150 ° C., inclusion: isopentane)
Hollow fine particles: F-2860D pre-foamed product (Matsumoto Yushi Seiyaku Co., Ltd., Matsumoto Microsphere F-2860D (used in a pre-foamed state by heat treatment), average particle size 50 μm, solid content 100% by mass, outer shell: Acrylonitrile polymer (softening temperature: 260 ° C, Tg: 170 ° C), inclusion: isopentane)

[Examples 7 to 8]
It is the aspect which laminated | stacked the base material on the back surface (surface opposite to a colored layer) of a porous heat insulation layer. In Example 1, dimethylformamide was added to polycarbonate-based polyurethane resin (manufactured by DIC Corporation, Crisbon TA-205) on the surface of the porous heat insulating layer formed on the release paper, and the viscosity was 5000 cps (B-type viscometer, rotor: No. 4, 12 rpm, 23 ° C.) The adhesive prepared using a knife coater was applied to an average coating thickness of 200 μm, and then pre-dried by heat treatment at 100 ° C. for 1 minute. The release paper was peeled off after being pressed with the substrate A or B for 1 minute at 39.2 N / cm ² . Subsequently, the polyurethane resin composition for the protective layer prepared according to the above-mentioned prescription 3 was applied to the surface of the colored layer after the release paper was peeled off, using a reverse coater so as to have an average thickness of 50 μm, and then dried. It processed at 100 degreeC with the machine for 3 minutes, the 10-micrometer-thick protective layer was formed, and the skin material of Examples 7-8 was obtained.

The base materials A and B are as follows.
-Base material A: Spunlace nonwoven fabric made of polyester (LMW-9003, manufactured by Vilene Co., Ltd., thickness 1.0 mm, specific gravity 0.040 g / cm ³ , tensile strength at 50% elongation at 150 ° C. 2.40 N / cm)
Base material B: Polypropylene foam sheet (25020-AP17, manufactured by Toray Industries, Inc., thickness 20 mm, specific gravity 0.040 g / cm ³ , tensile strength at 50% elongation at 150 ° C. 0.40 N / cm)

  About each skin material produced above, while measuring the tensile strength at the time of 50% elongation at 150 ° C. and the contact area ratio of the front surface, measurement of contact cooling feeling (Qmax) before and after molding, sensory evaluation of contact cooling feeling The sensory evaluation of the contact temperature feeling was performed, and the moldability was further evaluated. The results are shown in Table 2. Each measurement / evaluation method is as follows. In addition, it shows below also about each measuring method of the thickness of each resin layer of a skin material, the magnitude | size of the obstruction | occlusion hole of a porous heat insulation layer, and an obstruction | occlusion hole area ratio.

[Thickness of resin layer]
The vertical cross section of the skin material was observed with a microscope (manufactured by Keyence Corporation, Digital HF microscope VH-8000), the thicknesses at arbitrary 10 locations were measured, and the average value thereof was calculated.

[Size of blocking hole]
A vertical section of the skin material was observed with a microscope (manufactured by Keyence Corporation, Digital HF microscope VH-8000), and the maximum value was defined as the size of the blocking hole.

[Blockage area ratio]
A vertical cross section of the skin material is observed with a microscope (manufactured by Keyence Corporation, Digital HF microscope VH-8000), an image of the porous heat insulating layer is read into a personal computer, and the closed hole is painted white, and then the closed hole Then, the area ratio of the closed hole was calculated by binarizing the color of the part that was not so to white and black and counting the white dot part by integration.

[Contact area ratio]
Using a VK-8500 (manufactured by Keyence Corporation) as a laser microscope, the contact area ratio of the front surface of the skin material was calculated by the above method.

[Contact cold feeling (Qmax)]
Qmax was measured using a precise rapid thermophysical property measuring device (KES-F-M7 Thermolab II type, manufactured by Kato Tech Co., Ltd.). The measurement was performed on both a skin material before molding processing (before molding) described later and a skin material after molding processing (after molding). The used apparatus is provided with a sample stage on which a skin material as a sample is attached, and a detector. A copper thin plate is attached to one surface of the detector, and a temperature sensor is attached to the back surface of the copper thin plate. A heater is attached to the sample stage and the detector, and the temperature can be set independently by a control device. A skin material is affixed to the sample table, the sample table is set to 20 ° C by the control device, and the temperature of the copper thin plate of the detector is set to 30 ° C. Next, in the atmosphere of 20 ° C. × 60 RH, the front surface of the skin material on the sample table is brought into contact with the copper thin plate of the detector, and at the same time, the sensor output from the temperature sensor is recorded. At this time, the copper thin plate is deprived of heat by the sample stage through the skin material, and the temperature decreases. The maximum heat absorption rate (Qmax) at this time was measured. The larger the value of Qmax, the greater the feeling of cooling when touched by a person.

[Sensory evaluation of cool contact feeling]
The test piece was allowed to stand at 0 ° C. for 30 minutes, and then, when the subject brought the palm into contact with the front surface of the skin material, the cooling feeling felt by the subject was determined according to the following criteria. The evaluation was performed on both a skin material before molding processing (before molding) described later and a skin material after molding processing (after molding). In addition, the sensory evaluation by the subject calculated the average of the evaluation by 10 subjects.
6… No sudden temperature change is felt at all 5… Slight temperature change is felt slightly, but there is no discomfort 4… Slight temperature change is felt slightly, but there is no discomfort 3… Rapid temperature change 2… Slight discomfort 2… Severe sudden temperature changes are felt and uncomfortable 1… Sudden temperature changes are strongly felt and there is considerable discomfort

[Sensory evaluation of contact temperature]
The test piece was allowed to stand at 70 ° C. for 30 minutes, and then the contact temperature feeling felt by the subject when the subject brought the palm into contact with the front surface of the skin material was determined according to the following criteria. The evaluation was performed on both a skin material before molding processing (before molding) described later and a skin material after molding processing (after molding).
6… No sudden temperature change is felt at all 5… Slight temperature change is felt slightly, but there is no discomfort 4… Slight temperature change is felt slightly, but there is no discomfort 3… Rapid temperature change 2… Slight discomfort 2… Severe sudden temperature changes are felt and uncomfortable 1… Sudden temperature changes are strongly felt and there is considerable discomfort

[Molding processability (suitability for vacuum forming)]
The skin material was vacuum-formed using a simple vacuum forming machine (made by Formech International Limited, trade name “Compac Mini”). That is, the skin material was heated with a far-infrared heating device from both the front and back surfaces until the surface temperature reached about 150 ° C. The heated skin material was set in a mold heated to 80 ° C., and the pressure was reduced with a vacuum pump to an air pressure of 0.01 mPa or less so that the skin material adhered to the mold. After 10 seconds, the skin material was removed from the molding die to obtain a vacuum molded product. The test subject evaluated the external appearance of the obtained molded article according to the following criteria.
○… No wrinkles on the surface of the molded product, good quality △… Slightly wrinkled on the surface of the molded product ×… Many wrinkles on the surface of the molded product

  As shown in Table 2, in Comparative Examples 1 and 2, the effect of improving the feeling of contact cold / warm was obtained, but the skin material could not follow the three-dimensional shape of the molding surface at the time of molding, and the surface of the molded product Many wrinkles were generated. On the other hand, when it was Examples 1-16, generation | occurrence | production of the wrinkle on the surface of a molded article was suppressed and the skin material which can be used in the state with favorable sticking was obtained. In particular, Examples 1 to 10, 13 and 14 were excellent in molding processability while exhibiting an excellent holding effect of the feeling of contact cold / warmness after the molding process. In Example 16, since the glass transition point of the outer shell of the hollow fine particles is high, fine irregularities due to the hollow fine particles are generated on the surface of the molded product. Therefore, the quality is slightly inferior to that of Example 1.

DESCRIPTION OF SYMBOLS 1,1A ... Skin material 2 ... Porous heat insulation layer 3 ... Colored layer 4 ... Protective layer 5 ... Front surface of skin material 6 ... Base material

Claims (3)

A skin material for vehicle interior comprising a porous heat insulating layer and a colored layer laminated on the porous heat insulating layer,
The tensile strength, which is the tensile force per unit width at 50% elongation of the skin material under 150 ° C. condition, is 0.20 to 12.00 N / cm.
Skin material for vehicle interior. The front surface of the skin material has irregularities with a contact area ratio of 65% or less,
The porous heat insulating layer is formed by blending hollow fine particles with the resin that forms the matrix, the glass transition point of the resin forming the outer shell of the hollow fine particles is 50 to 150 ° C., and the softening temperature of the porous heat insulating layer is The skin material for vehicle interior according to claim 1, wherein the temperature is 110 to 250 ° C.   The skin material for vehicle interior according to claim 1 or 2, which is a skin material for an instrument panel or a door of a vehicle.

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