JP6357367B2 - Skin material and its manufacturing method - Google Patents

Description

  The present invention relates to a skin material in which natural leather is bonded to a resin foam and a method for producing the same.

  Conventionally, as a skin material for seats and interior materials for automobiles, railways, aircraft, furniture, etc., there is a skin material in which natural leather is bonded to polyurethane foam.

  As a method of bonding polyurethane foam and natural leather, polyurethane foam and natural leather are laminated with a non-woven hot-melt adhesive sandwiched between them, and the hot-melt adhesive is melted under pressure and heating to form natural leather and polyurethane foam. There exists what adhere | attaches a body (patent document 1).

  As another bonding method, an adhesive layer is formed by applying a powdered hot melt adhesive on one side of a polyurethane foam, and then laminating natural leather on the adhesive layer and pressing it with a hot platen. There is one that melts a hot-melt adhesive and bonds natural leather and polyurethane foam (Patent Document 2).

  However, in the method using a non-woven hot melt adhesive or a powder hot melt adhesive, when the natural leather and the polyurethane foam are bonded, heating from the polyurethane foam side improves the touch of the skin material. If the thickness of the polyurethane foam is 10 mm or more, sufficient heat cannot be transferred to the hot melt adhesive between the polyurethane foam and the natural leather due to the heat insulating effect of the polyurethane foam, and the polyurethane foam and the natural leather can be securely bonded. Disappear. Moreover, when heating temperature is raised in order to improve adhesiveness, the problem which a polyurethane foam heat-degenerates generate | occur | produces. Furthermore, when a backing base fabric made of nylon tricot or the like is bonded in advance to the back surface of the polyurethane foam in order to improve the sewing work of the skin material, there arises a problem that the backing base fabric shrinks due to heat.

  In addition, in order to ensure the adhesion between natural leather and polyurethane foam by hot melt adhesive, when heat is easily transferred to the hot melt adhesive by heating from the natural leather side, the heat is directly applied to the natural leather. The natural wrinkles (fine irregularities) on the leather's original surface are stretched by heat to become a flat surface, and the natural leather's original design is impaired, or the natural leather shrinks due to heat, A good skin material cannot be obtained.

In addition, natural leather retains moisture because of natural materials, and there is a problem that the moisture in the natural leather evaporates due to heating, thereby impairing hot melt adhesiveness.
Furthermore, in the method using a non-woven hot-melt adhesive, a continuous fiber structure remains at least between the natural leather and the polyurethane foam, so that the flexibility and flexibility of the skin material are impaired and become hard. There is.
If the heating temperature is lowered in order to prevent the above-mentioned problems caused by heating, the adhesiveness of the hot melt adhesive is lowered and the adhesion between natural leather and polyurethane foam is caused.

JP 2006-110960 A JP-A-3-247446

  This invention is made | formed in view of the said point, Comprising: Adhesion with natural leather and a resin foam is strong, and it aims at provision of the manufacturing method of the skin material which has the texture of favorable natural leather.

The invention according to claim 1 is a natural leather which is laminated and adhered to the surface of the resin foam with a resin foam and a moisture-curable hot melt adhesive applied in a molten state on the surface of the resin foam. A skin material comprising water-containing natural leather having natural wrinkles on its surface .

The invention of claim 2 is characterized in that, in claim 1, the moisture curable hot melt adhesive is a solventless urethane-based reactive hot-melt resin .

  The invention of claim 3 is characterized in that, in claim 1 or 2, the resin foam is a soft slab polyurethane foam.

  A fourth aspect of the invention is characterized in that, in any one of the first to third aspects, the resin foam is provided with a back base fabric on a surface that is not bonded to the natural leather.

The invention of claim 5 applies a moisture-curing hot melt adhesive melted by heating to the surface of one side of the resin foam, and sandwiches the hot melt adhesive in a molten state on the surface of the resin foam. Laminated water-containing natural leather having the natural texture of natural leather on the surface, and the resin foam and the laminated body of natural leather are laminated and then compressed without heating to cure the hot melt adhesive. In this way, a skin material in which the natural leather and the resin foam are bonded is obtained.

The invention of claim 6 is characterized in that, in claim 5, the moisture-curable hot melt adhesive is a solventless urethane-based reactive hot-melt resin .

  A seventh aspect of the invention is characterized in that, in the fifth or sixth aspect, a back base fabric is provided in advance on the surface of the resin foam that is not bonded to the natural leather.

  The invention of claim 8 is characterized in that, in any one of claims 5 to 7, the resin foam is a soft slab polyurethane foam.

According to the invention of claim 1, since the hot melt adhesive in a molten state is applied to the surface of the resin foam, the resin can be obtained without heating for melting the hot melt adhesive after laminating the natural leather. Adhesion between foam and natural leather is good, and the surface of natural leather is not stretched by heating, and the original design of natural leather is not impaired. It is done. Furthermore, since heating after laminating natural leather is unnecessary, there is no fear of heat deterioration or deformation of the resin foam due to heating, and a skin material of good quality can be obtained.
According to the invention of claim 1, since the hot melt adhesive is made of a moisture curable hot melt adhesive, the moisture curable hot melt adhesive is cured by moisture evaporated from natural leather, and the resin foam Good adhesion of natural leather.

According to the invention of claim 2, the moisture curable hot melt adhesive is a solvent-free urethane-based reactive heat-melting resin, which is preferable in order to pass the VOC standard for vehicle use.

  According to the invention of claim 3, since the resin foam is made of a soft slab polyurethane foam, the surface of the resin foam is exposed with the cut portions of the cell skeleton of the soft slab polyurethane foam being uneven, A hot melt adhesive in a molten state is engaged with the cell skeleton, so that the resin foam and the natural leather are more reliably bonded.

  According to the invention of claim 4, the back base fabric provided on the surface of the resin foam that is not bonded to the natural leather has no fear of thermal deterioration such as shrinkage because the resin foam is not heated. Good quality can be maintained, and the sewing work of the skin material can be made good by the back base fabric.

According to the invention of claim 5, the resin foam and the natural leather can be satisfactorily bonded without heating to melt the hot melt adhesive after lamination of the natural leather, and the natural leather is heated by heating. The surface texture of the skin is not elongated, and the natural leather original design is not impaired. Furthermore, since heating after laminating natural leather is unnecessary, there is no fear of heat deterioration or deformation of the resin foam due to heating, and a skin material of good quality can be obtained.
According to the invention of claim 5, since the hot melt adhesive is made of a moisture curable hot melt adhesive, the moisture curable hot melt adhesive is cured by moisture evaporated from natural leather, and the resin foam Good adhesion of natural leather.

According to the sixth aspect of the present invention, the moisture curable hot melt adhesive is a solventless urethane-based reactive hot-melt resin, which is preferable in order to pass the VOC standard for vehicle use.

  According to the seventh aspect of the present invention, the back base fabric provided on the surface of the resin foam that is not bonded to the natural leather is free from heat deterioration such as shrinkage because the resin foam is not heated. Good quality can be maintained, and the sewing work of the obtained skin material can be made good by the back base fabric.

  According to the invention of claim 8, since the resin foam is made of a soft slab polyurethane foam, the surface of the resin foam is exposed with the cut portions of the cell skeleton of the soft slab polyurethane foam being uneven, A hot melt adhesive in a molten state is engaged with the cell skeleton, so that the resin foam and the natural leather are more reliably bonded.

It is sectional drawing of the skin material which concerns on 1st Embodiment of this invention. It is sectional drawing which shows application | coating of the hot-melt-adhesive agent of a molten state. It is sectional drawing which shows lamination | stacking of natural leather. It is sectional drawing which shows compression. It is sectional drawing of the skin material which concerns on 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described.
A skin material 10 of the first embodiment shown in FIG. 1 is suitable as a skin material for seats and interior materials of automobiles, railways, aircrafts, furniture, etc., and includes a resin foam 11 and the resin foam 11. And a natural leather 31 laminated and adhered to the surface of the resin foam 11 with a hot melt adhesive 21 applied in a molten state on the surface of the resin foam 11.

  The resin foam 11 is not particularly limited, and examples thereof include a soft polyurethane foam, a polyethylene foam, and a polypropylene foam. In particular, a soft slab polyurethane foam obtained by cutting a block-like soft polyurethane foam produced by slab foaming continuously foamed at normal temperature and normal pressure into a sheet shape is suitable as the resin foam 11. In the soft slab polyurethane foam, since the cut part of the cell skeleton is exposed as irregularities on the cut surface, the hot melt adhesive 21 engages with the surface of the soft slab polyurethane foam and the resin foam 11 And the adhesive strength of the natural leather 31 is increased.

In addition, since the skin material 10 is not heated to a high temperature when the skin material 10 is manufactured, a polyethylene foam having a low melting point can be used as the resin foam 11.
Although the thickness of the said resin foam 11 is suitably set according to the use of the said skin material 10, 2-20 mm is mentioned as an example.

  In the resin foam 11, the back base fabric 15 is bonded in advance to the surface not bonded to the natural leather 31 with a frame laminate or an emulsion adhesive. The back base fabric 15 suppresses the elongation of the skin material 11 when the skin material 11 is sewn, makes the back surface of the skin material 11 slip well, and facilitates the cloth feed on the sewing machine base. Or the thing which has the effect | action which protects a back surface at the time of use of the said skin material 11, and consists of a cloth material (knitted fabric, woven fabric), a nonwoven fabric, etc. is mentioned.

  The hot melt adhesive 21 applied in a molten state to the surface to which the natural leather 31 is bonded in the resin foam 11 is a normal one made of a thermoplastic plastic such as vinyl acetate resin, or melted by heating. And moisture-curing type that is reactively cured by moisture. In particular, the moisture-curing hot melt adhesive is accelerated not only by moisture in the air but also by using moisture naturally contained in the natural leather 31, so that the moisture contained in the natural leather 31 Since the adhesiveness is not impaired and the adhesiveness can be improved on the contrary, it is preferable as the hot melt adhesive 21. As the moisture curable hot melt adhesive, there are urethane type, polyester type, acrylic type and the like, and urethane type moisture curable adhesive is preferable from the viewpoint of easy handling and availability. Specifically, it is a urethane-based reactive hot melt adhesive, and a solvent-free reactive hot-melt resin that does not contain a diluent such as an organic solvent is preferable in order to pass the VOC standard for vehicle use. This adhesive is mainly composed of an isocyanate group-terminated urethane polymer, and a polyol component such as polyester polyol or polyether polyol is generally used. However, other polyols may be used. Any urethane compound having an isocyanate group as a reactive group may be used. The heat melting temperature is 70 ° C to 200 ° C, preferably 80 ° C to 160 ° C.

  The natural leather 31 is determined according to the use of the skin material 10 such as cowhide, pig leather, kangaroo, ostrich, crocodile and other reptiles. In particular, natural leather made of cowhide is preferable because of its excellent durability. The thickness of the natural leather is 0.5 to 3 mm.

  A method for manufacturing the skin material 10 will be described. The skin material 10 is manufactured by a hot melt adhesive coating process, a natural leather laminating process, and a compression curing process.

  In the hot melt adhesive application step, the hot melt adhesive 21 melted by heating is applied to one surface of the resin foam 11 by an application device. The resin foam 11 is formed into a sheet with a predetermined thickness in advance, and when the back base fabric 15 is bonded to the lower surface (back surface), the resin foam 11 on the side opposite to the back base fabric 15 The hot melt adhesive 21 is applied to the surface.

  FIG. 2 shows a case where a roll coater is used as the coating device. The roll coater 40 includes a feed roll 41, a supply roll 42, an application roll 43, and a hot melt adhesive storage tank 44.

The feed roll 41 is disposed below the resin foam 11 and rotates in one direction while being in contact with the back base fabric 15 on the lower surface of the resin foam 11. Send in the direction.
The supply roll 42 and the coating roll 43 are arranged above the resin foam 11 with their rotation axes parallel to each other and with a gap between their outer peripheral surfaces. The supply roll 42 rotates in the direction opposite to the feeding direction of the resin foam 11 without the outer peripheral surface being in contact with the upper surface of the resin foam 11. On the other hand, the application roll 43 rotates in the feeding direction of the resin foam 11 with a predetermined amount of distance (clearance) between the outer peripheral surface and the upper surface of the resin foam 11. The supply roll 42 and the application roll 43 are configured such that the outer peripheral surfaces can be heated.

  The hot-melt adhesive reservoir 44 is disposed such that the lower discharge portion 45 is positioned between the supply roll 42 and the coating roll 43, and the hot-melt adhesive 21 accommodated therein is used as a heater or the like. It heats with this heating means and stores in a molten state.

  The molten hot melt adhesive 21 stored in the hot melt adhesive storage tank 44 is supplied from the discharge unit 45 in a state where the resin foam 11 is fed in one direction by the feed roll 41. Supplied between the supply roll 42 and the coating roll 43. The molten hot melt adhesive 21 supplied between the supply roll 42 and the application roll 43 is supplied to the upper surface of the resin foam 11 by the rotation of the supply roll 42 and the application roll 43. The molten hot melt adhesive 21 supplied to the upper surface of the resin foam 11 is applied to the upper surface of the resin foam 11 in contact with the lower end of the outer peripheral surface of the rotating application roll 43.

  The application amount of the hot melt adhesive 21 to the resin foam 11 is the melt viscosity of the hot melt adhesive 21 depending on the heating temperature of the hot melt adhesive storage tank 44, the supply roll 42 and the application roll 43. Adjustment may be made by adjusting the rotation speed of the supply roll 42 and the coating roll 43, the distance (clearance) between the outer peripheral surface of the coating roll 43 and the top surface of the resin foam 11, and the feed speed of the resin foam 11. it can.

  In the natural leather laminating step, as shown in FIG. 3, the natural leather 31 is laminated on the surface of the resin foam 11 with the hot melt adhesive 21 in a molten state interposed therebetween. In the embodiment shown in FIG. 3, the resin foam 11 to which the hot melt adhesive 21 in the molten state is applied is placed on the upper surface of the lower mold 51 of the press device, and then the hot melt adhesive 21 in the molten state. On top of this, the natural leather 31 is laminated with its back side facing down. Reference numeral 52 denotes an upper die of the press device.

  In the compression curing step, as shown in FIG. 4, the laminated body 10A in which the natural leather 31 is laminated on the upper surface of the resin foam 11 with the hot melt adhesive 21 in a molten state interposed therebetween is compressed, and the hot melt The adhesive 21 is cured to form the skin material 10 in which the natural leather 31 and the resin foam 11 are bonded. The compression is performed at a temperature lower than the melting point of the hot melt adhesive 21. For example, it is performed at room temperature. In addition, normal temperature means the range of 20 ± 15 degreeC prescribed | regulated by Japanese Industrial Standard. Further, the degree of compression is not particularly limited, and for example, the compression is performed so as to be 40 to 80% of the total thickness.

  The hot melt adhesive 21 is naturally cooled and cured during the compression, and bonds the natural leather 31 and the resin foam 11. When the hot melt adhesive 21 is a moisture curable hot melt adhesive, the cooling proceeds by natural cooling, moisture in the air, and moisture naturally released from the natural leather 31, and the natural leather 31 and the Adhesion of the resin foam 11 becomes strong.

  In the compression step, high-temperature heating for melting the hot melt adhesive 21 is not performed, so that the surface of the natural leather 31 is not stretched or the original design of the natural leather 31 is not impaired. A skin material 10 having a good texture can be obtained. Further, the back base fabric 15 is not deteriorated by heat, and the skin material 10 of good quality can be obtained.

FIG. 5 shows a skin material 60 of the second embodiment. The skin material 60 of 2nd Embodiment does not have the said back base fabric 15 in the skin material 10 of 1st Embodiment, and another structure consists of the structure similar to the skin material 10 of 1st Embodiment. Reference numeral 61 is a resin foam, 71 is a hot melt adhesive, and 81 is natural leather.
The manufacturing method of the skin material 60 of 2nd Embodiment is the manufacturing method of the skin material 10 of the said 1st Embodiment, except that the back base fabric 15 is not adhere | attached on the lower surface of the said resin foam 11, It is the same as that of the manufacturing method of the skin material 10 of 1st Embodiment.

Examples 1 to 3 (with moisture-curing hot melt adhesive and backing fabric)
Density 30 kg / m ³ , hardness (JIS K6400-2: 2012) 50N, number of cells (JIS K6400-1: 2004) 42/25 mm, product number: EL-68WS, polyether-based soft slab manufactured by INOAC Corporation The polyurethane foam was used as a resin foam with a size of 250 × 400 mm × thickness 10 mm, and 15 denier of nylon tricot was bonded to the back surface with an acrylic emulsion adhesive as a backing base fabric.

  As the hot-melt adhesive, urethane-based moisture-curable adhesive, polyurethane-based hot-melt moisture-curable resin manufactured by Hitachi Chemical Polymer Co., Ltd., Hibon, melt coating temperature: 150 ° C., and 150 ° C. by the roll coater 40 In a heated and melted state, the resin foam was applied and adhered to the surface opposite to the back base fabric. The temperature of the hot melt adhesive stored in the hot melt adhesive storage tank 44, the temperature of the supply roll 42 and the application roll 43 are both 80 ° C., the rotational speed of the supply roll 42 and the application roll 43, and The value of the clearance was fixed, and the feed rate of the resin foam was changed at 4 to 6 m / min to obtain the adhesion amounts (application amounts) of Examples 1 to 3 shown in Table 1.

  Next, the resin foam is placed on the lower mold with the hot melt adhesive facing upward, and natural leather (cowhide) is laminated on the resin foam with the hot melt adhesive on the surface of the resin foam sandwiched. The upper mold was lowered and compressed to form the skin materials of Examples 1 to 3 shown in Table 1. The compression was performed at room temperature for 40 seconds, and the compression amount was set to 60%.

・Reference Example 4 (with normal hot melt adhesive and backing fabric)
As the hot melt adhesive, a vinyl acetate hot melt adhesive manufactured by Aika Kogyo Co., Ltd., product name: A-QNJ is used, the resin foam and the back base fabric are the same as in Examples 1 to 3, and the hot melt adhesive reservoir The temperature of the hot melt adhesive stored in 44 and the temperature of the supply roll 42 and the application roll 43 are set to 95 ° C., the rotational speed of the supply roll 42 and the application roll 43 and the clearance value are fixed, and the resin foam The body feed rate was adjusted to the adhesion amount (application amount) of Reference Example 4 in Table 1. Otherwise, the skin material of Reference Example 4 shown in Table 1 was formed in the same manner as in Examples 1 to 3.

・ Comparative example 1 (with non-woven type hot melt adhesive, backing fabric)
As a web-like hot melt adhesive (nonwoven fabric type hot melt adhesive), a spunbond nonwoven fabric, basis weight: 25 g / m ² , melting point: 115 ° C., product number: Dynac LNS1225, manufactured by Kureha Tech Co., Ltd. The back base fabric is the same as in Examples 1 to 3, and the resin foam is placed on the lower mold so that the back base fabric is on the lower side, and the hot melt adhesive is placed on the upper surface of the resin foam And the natural leather (cowhide) was laminated | stacked on both sides of the hot-melt-adhesive, the press upper mold | type was dropped and heat-compressed, and the skin material of the comparative example 1 shown in Table 1 was formed. The press lower mold was set at room temperature, the upper mold was set at 190 ° C. for 40 seconds, and the compression amount was set to 50%.

Examples 5 to 7 (moisture curable hot melt adhesive, no backing fabric)
Density 30kg / m ³ , hardness (JIS K6400-2: 2012) 70N, number of cells (JIS K6400-1: 2004) 25 / 25mm, product number: WF-18, polyether-based soft slab manufactured by Inoac Corporation The polyurethane foam was used as a resin foam with a size of 250 × 400 mm × thickness 10 mm, and no backing base fabric was provided. The same hot melt adhesive as in Examples 1 to 3 was used, and in the same manner as in Examples 1 to 3, the hot melt adhesive in a molten state was formed on one side surface of the resin foam. Adhesion (application) was performed at the indicated adhesion amount.

  Next, the resin foam is placed on the lower mold with the hot melt adhesive facing upward, and natural leather (cowhide) is laminated on the resin foam with the hot melt adhesive on the surface of the resin foam sandwiched. The upper mold was lowered and compressed to form skin materials of Examples 5 to 7 shown in Table 2. The compression was performed at room temperature for 40 seconds, and the compression amount was set to 50%.

Reference Example 8 (Normal type hot melt adhesive, no backing fabric)
As a hot melt adhesive, a vinyl acetate hot melt adhesive manufactured by Aika Kogyo Co., Ltd., product name: A-QNJ was used, and the resin foam was the same as in Examples 5 to 7, and stored in the hot melt adhesive storage tank 44. The temperature of the hot melt adhesive and the temperature of the supply roll 42 and the application roll 43 are set to 130 ° C., the rotational speed of the supply roll 42 and the application roll 43 and the clearance value are fixed, and the resin foam feed speed Was set to 5 m / min to obtain the adhesion amount (coating amount) of Reference Example 8 in Table 2. Otherwise, the skin material of Reference Example 8 shown in Table 2 was formed in the same manner as in Examples 5-7.

Comparative Example 2 (Non-woven fabric hot melt adhesive, no backing fabric)
As the web-like hot melt adhesive, a spunbond nonwoven fabric, basis weight: 25 g / m ² , melting point: 115 ° C., product number: Dynac LNS1225, manufactured by Kureha Tech Co., Ltd., and the resin foam is the same as in Examples 5-7 The resin foam is placed on the lower mold of the press, hot melt adhesive is placed on the surface of the resin foam, natural leather (cowhide) is laminated with the hot melt adhesive sandwiched, and the press The mold was lowered and heat-compressed to form a skin material of Comparative Example 2 shown in Table 2. The lower press mold was at room temperature, the upper mold was performed at 190 for 40 seconds, and the compression amount was set to 50%.

The peel strength, hardness, appearance, shrinkage, and heat resistant adhesive strength were measured for the skin materials of each Example, each Reference Example, and each Comparative Example. The measurement results are shown in Tables 1 and 2.

The peel strength (unit: N / 25 mm) was measured based on JIS K 6854-2 (adhesive-peeling peel strength test method, second part: 180 degree peel). The number of tests n is 3. The skin material was cut into 250 mm × 400 mm, and the direction of 400 mm was vertical and the direction of 250 mm was horizontal. "*" Written together with the measured numerical value indicates that the peel strength is broken due to high adhesive strength.
The hardness (unit N) was measured based on a push-pull gauge (FS probe). The larger the value, the harder. The measurement of hardness is centered on a push-pull shaft with a hemispherical contact part with a diameter of 10 mm, and a push-pull gauge (manufactured by SUNEX Co., Ltd., FS100) that vertically positions a sample with a hollow disk with a diameter of 50 cm is used. Then, the contact portion was pushed down to the sample side to read the numerical value.
As for the appearance, it was visually observed whether or not wrinkles were reduced on the surface of natural leather or unsightly avatars (irregularities) were generated. In the observation result of “wrinkle reduction”, “x” indicates that a clear reduction of the wrinkle was observed, and “◯” indicates that no wrinkle reduction was observed. “Δ” in the observation result of “Avatar” indicates that an unsightly avatar (unevenness) was partially seen, and “◯” indicates that an unsightly avatar (unevenness) was not observed.

  For shrinkage (mm), the amount of shrinkage of the actually molded sample was measured. In both Examples and Comparative Examples, raw leather before molding cut into a predetermined shape is prepared as a standard, and after the adhesive is melt-coated, the amount of shrinkage of the raw leather laminated with resin foam after being pressed at room temperature Was measured. The size of the standard skin material was cut into 250 mm × 400 mm, the direction of 400 mm was vertical, and the direction of 250 mm was horizontal. “◯” in the measurement results indicates that the shrinkage is less than 3 mm within the range that can be used as a laminated skin material in both the vertical direction and the horizontal direction, and “×” indicates the standard raw material leather On the other hand, it shows that the shrinkage difference generated in the laminated skin material is shrinkage exceeding 3 mm.

  For the heat-resistant adhesive strength, a test piece for peeling test, 25 mm in width and 175 mm in length was prepared, peeled leaving 75 mm, a 10 g weight was attached to the end of the peeled skin material, and the peeled test piece The heat resistant adhesive strength was measured by hanging one end as an upper end and leaving it in a constant temperature bath at 140 ° C. for 24 hours. Those that passed the test were rated as “◯”, and the peeled distance was less than 5 mm, and the weight remained unloaded. Those that failed the test were marked with “x”. At the end of the test, the test piece was peeled off and the weight was dropped.

As shown in Tables 1 and 2, the skin material of each example in which a hot melt adhesive was melted and adhered to the resin foam side had high peel strength between the natural leather and the resin foam, and the hardness was soft. Is suitable for use as a skin material for seats and interior materials of automobiles, railways, aircraft, furniture, and the like. In Examples 1 to 3 and Reference Example 4 having the backing fabric, the backing fabric was not deteriorated by heat and had good quality. Furthermore, when a moisture-curing adhesive was used, the peel strength (heat-resistant adhesive strength) was high and durable in a high temperature environment.
On the other hand, each comparative example using a non-woven fabric as a hot melt adhesive and heat-pressed after laminating natural leather has low peel strength between the natural leather and the resin foam, the hardness is hard, and the wrinkles on the natural leather surface are reduced. In addition, unsightly avatars are generated, the texture of natural leather is impaired, and the shrinkage is large, making it unsuitable as a skin material for seats and interior materials of automobiles, railways, aircraft, furniture, and the like.

10, 60 Surface material 10A Laminate 11, 61 Resin foam 15 Back base fabric 21, 71 Hot melt adhesive 31, 81 Natural leather 40 Roll coater 41 Feed roll 42 Supply roll 43 Application roll 44 Hot melt adhesive storage tank

Claims (8)

A natural wrinkle inherent to natural leather that is laminated and bonded to the surface of the resin foam with a resin foam and a moisture curable hot melt adhesive applied in a molten state on the surface of the resin foam on the surface A skin material comprising natural water-containing leather. The skin material according to claim 1, wherein the moisture-curable hot melt adhesive is a solventless urethane-based reactive hot-melt resin .   The skin material according to claim 1 or 2, wherein the resin foam is a soft slab polyurethane foam.   The skin material according to any one of claims 1 to 3, wherein a back base fabric is provided on a surface of the resin foam that is not bonded to the natural leather. Apply a moisture-curing hot melt adhesive melted by heating to the surface of one side of the resin foam,
Laminating natural leather containing natural leather on its surface on the surface of the resin foam with the hot melt adhesive in a molten state sandwiched,
After laminating the resin foam and the laminated body of natural leather , by compressing without heating and curing the hot melt adhesive, a skin material in which the natural leather and the resin foam are bonded is obtained. A method for producing a skin material characterized by the above. The method for producing a skin material according to claim 5, wherein the moisture-curable hot-melt adhesive is a solventless urethane-based reactive hot-melt resin .   The method for producing a skin material according to claim 5 or 6, wherein a back base fabric is provided in advance on a surface of the resin foam that is not bonded to the natural leather.   The said resin foam is a soft slab polyurethane foam, The manufacturing method of the skin material as described in any one of Claim 5 to 7 characterized by the above-mentioned.

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