JPH0353109B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a laminate in which a face material is laminated and integrated on one or both sides of a flexible polyurethane foam by hot pressing, and particularly to a method for suitably manufacturing a laminate having an uneven shape. Traditionally, two- or three-layer laminates have been used as vehicle interior materials by fusing and integrating thermoplastic resin films, leather, woven fabrics, non-woven fabrics, etc. on one or both sides of a soft polyurethane foam to give an uneven pattern. , used as furniture materials, wall materials, floor materials, etc.
Currently, such laminates are mainly manufactured by high-frequency welding, but this method requires very high-cost special forms, expensive welding machines, and the surface material is chlorinated. It has the disadvantage of being limited to vinyl, etc. In addition to the high-frequency welding method, a method has been proposed in which a special foamable hardening resin is applied to the foam surface and then heat-pressed to form the shape. In addition to requiring a complicated process of applying the material, there are restrictions such as the need to perform the coating process and the shaping process in succession. In view of the above circumstances, the present inventors used a cost-effective heat press method to easily and reliably form an uneven pattern on a soft polyurethane foam and a face material without requiring any special form or process. As a result of conducting various studies on methods for laminating and integrating the soft polyurethane foam, we found that the soft polyurethane foam and the face material were heat-pressed using a mold having an uneven shape, and the face material was laminated and integrated on one or both sides of the soft polyurethane foam. In the method, a soft polyurethane foam with an air permeability of 40 cm ³ /cm ² /second or more in a Frazier type tester based on the cotton fabric test method of JIS-L1004-1972 is used, and the above surface material is laminated. A thermoplastic resin composition is applied to the surface of the soft polyurethane foam at a concentration of 40 to 150 per laminated surface.
Coat the soft polyurethane foam in advance so that it penetrates 1 mm or more into the interior of the soft polyurethane foam at a coating weight of g/ ^m2 , and heat-press at a temperature 10°C or more higher than the softening point of the thermoplastic resin composition. , 10 to 70 degrees Celsius lower than the melting temperature of the surface material, and -40 degrees Celsius, the temperature at which soft polyurethane foam can be hot-pressed.
The present invention was made based on the finding that the above object can be achieved by setting the temperature in the range of ~+50°C. That is, in the present application, a thermoplastic resin composition is coated on a soft polyurethane foam in advance, and the soft polyurethane foam and a face material are hot-pressed using, for example, a mold having uneven parts, thereby forming a molten thermoplastic resin composition. The material penetrates into the foam, greatly improving the thermoformability of the mold, especially the pressed foam part (welder part) by the convex part, and in this case, this also goes hand in hand with the high thermoformability of the polyurethane foam. Even immediately after the mold is removed at high temperature, the molded shape is prevented from collapsing due to the restoring force of the foam, and a clear weld line can be obtained. Also,
In this application, we used a soft polyurethane foam whose air permeability was 40 or more in terms of passing air volume (cm ³ /cm ² /sec) using a Frazier type tester based on the cotton fabric testing method of JIS-L1004-1972. When applying a thermoplastic resin composition, the composition penetrates into the inside of the foam, improving adhesive strength, and reducing the amount of the thermoplastic resin composition applied to the soft polyurethane foam by one lamination side (single side).
By applying the thermoplastic resin composition to a surface of 40 to 150 g/m ² and permeating the foam surface by 1 mm or more, a clear weld line can be formed easily and reliably, and at a low cost. It is possible to obtain reliable heat fusion properties advantageously and without hardening the foam. Furthermore, in the present application, the heat press temperature is set to be 10°C or more higher than the softening point of the thermoplastic resin composition, 10 to 70°C lower than the melting temperature of the surface material, and -40°C lower than the hot pressable temperature of the flexible polyurethane foam.
The temperature should be in the range of ℃ to +50℃, and the interrelationship between the heat press temperature and the softening point of the thermoplastic resin composition, the melting temperature of the surface material, and the hot pressable temperature of the flexible polyurethane foam is as follows. By regulating the above, a clear weld line can be obtained by shaping and forming at a low temperature and in a short time, and it also avoids the melting of the face material due to heat, which is the biggest problem in integral heat pressing of polyurethane foam and face material.
Can prevent expansion and contraction. The present invention will be explained in more detail below. In the present invention, an ether-based flexible polyurethane foam or an ester-based flexible polyurethane foam is used as the flexible polyurethane foam. In this case, the flexible polyurethane foam is
The air permeability of this type of foam is 40 or more, preferably 80 or more in terms of air passing rate (cm ³ /cm ² /sec) using a Frazier type tester based on the cotton fabric testing method of JIS-L1004-1972. By using a foam, when applying a thermoplastic resin composition, the composition can easily penetrate not only onto the surface of the foam, but also into the inside of the foam, further improving adhesive strength. In addition, in order to improve thermal adhesion, foam raw materials are foamed by adding vinyl chloride resin, plasticizers, etc. as thermal adhesion improving ingredients, and soft polyurethane foam is made of vinyl chloride resin paste or vinylidene chloride resin lattice. It is also possible to use a material impregnated with a heat fusion improver such as . As the soft polyurethane foam, a normal polyurethane foam with a cell membrane can be used, but a reticulated foam without a cell membrane can be particularly preferably used, and by using this reticulated foam, a thermoplastic resin composition can be formed. easily penetrates into the foam, further improving adhesive strength. Furthermore, as the flexible polyurethane foam, one having an apparent density of 0.014 to 0.05 is preferably used. In addition, as a soft polyurethane foam, heat pressable temperature (20 mm thick urethane foam is compressed to 4 mm and held for 120 seconds, and after releasing the press
The minimum pressing temperature at which the foam thickness is 4.5 mm or less after a certain period of time is referred to as the heat-pressable temperature of the foam is preferably 200°C or less, particularly 180°C or less, and thereby, It becomes possible to perform heat pressing at a lower temperature. In addition, in order to improve the heat resistance of the laminate and to perform heat pressing at a lower temperature, the thermoplastic resin composition has a softening point of 60 to 180°C, especially
It is preferable that the temperature is 80 to 150°C, and for example, hot melt adhesives such as polyamide resin and polyester resin can be used.
etc. Further, when carrying out the present invention, the coating amount of the thermoplastic resin composition on the flexible polyurethane foam is 1
40 to 150 g/ ^m2 per laminated surface (single side),
If the coating amount is less than 40 g/m ² , sufficient thermal adhesion will not be obtained, causing problems in forming clear weld lines, and if it is used in excess of 150 g/m ² , it will be disadvantageous in terms of cost. , and the foam becomes stiffer. Furthermore, the thermoplastic resin composition must penetrate 1 mm or more, especially 2 mm or more, into the interior of the polyurethane foam surface, thereby ensuring reliable thermal fusion properties and ensuring clarity of the weld line. I can do it. In addition, in this case, the thickness of the non-permeable part of the thermoplastic resin composition of the polyurethane foam is
It is preferably 30 mm or less, especially 20 mm or less,
This reliably prevents inconveniences such as the welded portion lifting up after hot press molding. The thermoplastic resin composition may be applied to the entire surface of the urethane foam, or may be applied only to the portion that will be fused to the face material. The thermoplastic resin composition is preferably uniformly coated using a roll coater method, spray method, curtain flow coater method, or spot coated using a gravure coater method. When can you increase your penetration level? In addition, the thermoplastic resin composition may be solidified by adhering the face material before solidifying after application, or may be solidified without adhering the face material. Furthermore, in the present invention, immediately after coating the thermoplastic resin composition, while maintaining adhesive properties, thermoplastic resins such as vinyl chloride resin powder, vinylidene chloride resin powder, acrylic resin powder, vinyl chloride-vinyl acetate copolymer, etc. The powder can also be spread on the thermoplastic resin composition and fixed thereon, thereby further improving the heat fusion properties. Further, in the present invention, a thin film of a thermoplastic resin may be laminated onto the thermoplastic resin composition instead of the thermoplastic resin powder, or in addition to being sprayed. Furthermore, in the present invention, a thermoplastic resin composition can be applied to the surface of the face material that comes into contact with the urethane foam in order to further improve the heat fusion properties. In this case, the thermoplastic resin composition may be applied to the entire surface of the face material that is in contact with the urethane foam, or may be applied only to the portion that is fused to the urethane foam. In addition, as the thermoplastic resin composition, those similar to those mentioned above can be used. Furthermore, while the thermoplastic resin composition coated on the face material maintains its adhesive properties, the vinyl chloride resin powder,
Thermoplastic resin powder such as vinylidene chloride resin powder may be sprinkled and fixed, thereby further improving the heat fusion properties. Note that instead of coating the face material with a thermoplastic resin, a solution type or emulsion type adhesive may be applied, and instead of spraying thermoplastic resin powder, a thermoplastic resin thin film similar to the above may be applied. It can also be laminated. As described above, in the present invention, a thermoplastic resin composition is applied in advance to the surface on which the soft polyurethane foam face material is to be laminated, and the soft polyurethane foam and the face material are hot pressed using a mold having an uneven shape. There are no particular restrictions on the type of surface material, but in the present invention, natural fiber woven fabric or non-woven fabric, soft vinyl chloride resin, polyamide resin, acrylic resin, vinylidene chloride resin, etc. are used as the surface material. Synthetic resin film, leather, woven fabric, or non-woven fabric as the back side material, or the same as the front side material, or self-supporting resin board, hardboard, plywood, wood board, cardboard board, metal plate, synthetic resin board, etc. A plate material having the following properties is preferably used. In this case, it is preferable to use a material with an elongation rate of 50% or more, especially 100% or more in one or both axial directions as the surface material. You can get a body. Note that the surface material having a melting temperature of 160 to 240°C is preferably used. Further, as the surface material, a material whose surface is brushed or flocked may be used. In addition, when using film, leather, woven fabric, or non-woven fabric as the back side material, it is preferable to use a material with an elongation rate of 10% or less, especially 2% or less in one or both axial directions. It is possible to obtain a laminate having excellent properties such as: In the present invention, only the above-mentioned front surface material or both the front surface material and the back surface material are used, and hot pressing is performed from the front surface material side, but in particular, both the front surface material and the back surface material are used. When used, it is possible to obtain a laminate having a sandwich structure that can be suitably used as an interior material for automobiles. In this way, when manufacturing a laminate with a sandwich structure, the amount of the thermoplastic resin composition applied to the back side material side is greater than the amount applied to the front side material side. It is possible to improve the fusion properties between the material and the soft polyurethane foam. In the present invention, it is preferable to heat press so that the thickness of the welded portion is 20% or less of the original thickness of the polyurethane foam, thereby making it possible to obtain a clear welded line. Further, in the present invention, the hot press temperature is set to be 10°C or more higher than the softening point of the thermoplastic resin composition, preferably 20°C or more higher than the melting temperature of the surface material.
-70°C, preferably 20 to 50°C lower, and -40°C, which is the temperature at which flexible polyurethane foam can be hot-pressed
The temperature is in the range of ~+50°C, preferably -20~+30°C. That is, if the heat press temperature is too lower than the softening temperature of the thermoplastic resin, the thermoplastic resin will not be softened by the heat press, and therefore the thermoplastic resin will not act as an adhesive or an auxiliary agent for forming uneven shapes by hot press. , it is not possible to perform good shaping by hot pressing, but by increasing the hot pressing temperature by 10°C or more higher than the softening temperature of the thermoplastic resin,
Such inconvenience can be prevented. In addition, if the heat press temperature is too high compared to the melting temperature of the facing material, the appearance of the facing material will be damaged by thermal damage, and in severe cases, the facing material will melt and tear.
The product value will be completely lost. On the other hand, if the heat press temperature is too low compared to the melting temperature of the face material, the face material will not soften and the sharp stamping die created by the uneven blade will not stick to the face material during heat pressing, resulting in a clear weld line. I can't. On the other hand, the heat press temperature is 10 to 70℃ higher than the melting temperature of the face material.
If it is made lower, the above-mentioned problem will not occur. Furthermore, in the present application, since the thermoplastic resin acts as an auxiliary agent for forming the uneven shape, the heat press temperature can be lowered compared to the normal uneven heat press that does not use a thermoplastic resin. If the temperature is too low compared to the heat press temperature, the form will hardly be shaped by heat, and the uneven shape will be formed only by the auxiliary effect of the thermoplastic resin, making it impossible to obtain a clear weld line. In addition, when the press mold is raised immediately after hot press molding, the uneven shape may collapse. On the other hand, if the heat press temperature is too high compared to the heat pressable temperature of the foam, there will be no problem in obtaining clear weld lines or uneven shapes, but the polyurethane foam will deteriorate due to heat.
Its strength may decrease or it may become more prone to weakening due to repeated compression during use. On the other hand, by setting the heat press temperature to a temperature in the range of -40℃ to +50℃ of the heat press temperature of polyurethane foam,
There is something that can solve the above problem. The heat pressing may be performed continuously using a shaping roll or a shaping conveyor, or may be performed in batches using a heat press machine. Furthermore, in the present invention, after the hot press mold is removed and before the thermoplastic resin composition is cured, it is possible to further press the thermoplastic resin composition using a mold having a temperature lower than the softening point of the thermoplastic resin composition. This can reliably prevent the welder pattern from losing its shape. As described above, according to the method for manufacturing a laminate according to the present invention, a laminate having clear weld lines can be obtained easily, reliably, and inexpensively. Furthermore, according to the method of the present invention, molding can be carried out at a lower temperature and in a shorter time than when the urethane foam and the face material are integrated by the conventional heat press method, thereby making it possible to form the urethane foam and the fabric etc. It is possible to prevent melting, expansion and contraction of fabrics, etc. due to heat, which is the biggest problem in integral heat presses. Further, according to the present invention, after coating the thermoplastic resin,
It is possible to shape and mold immediately on the same line, or it is possible to laminate face materials when applying thermoplastic resin to create a two- or three-layer laminate product, which can be shaped and molded at any time. It has various advantages, such as being able to do the same thing (only a shaping device is required). EXAMPLES The present invention will be specifically explained below with reference to Examples. [Examples 1 to 5] Using the soft polyurethane foam, front side material, back side material, thermoplastic resin composition, and hot press conditions shown in Table 1, the first press was carried out using the apparatus shown in FIGS. The laminates of Examples 1 to 5 shown in the table were manufactured, the thickness of the welded part (t ₁ ) and the thickness of the non-weldered part (t ₂ ) of the laminate were measured, and the original thickness of the foam ( t ₀ ). The results are shown in Table 2. Note that in Table 2, the level difference refers to the difference in thickness between the welded portion and the non-welded portion, and is related to the float and the hardness of the foam. The larger the float and step, the clearer the weld line. Description of the Apparatus FIG. 1 shows an apparatus for manufacturing the laminate of this example. In this apparatus, hot melt coating applicators 2 and 3 are first applied to the front and back surfaces of a flexible polyurethane foam 1 that moves in the direction of the arrow.
Immediately after, the front side material 6 and the back side material 7 are respectively laminated on the front and back surfaces of the form 1 using pressure rolls 4 and 5, and then the movement of the form is stopped, A laminate is produced by hot pressing using a hot press device 8. This heat press device 8 performs heat pressing using a flat press table 8a and a mold plate 8b having an uneven shape. be. Also,
In the figure, a is 5mm, b is 20mm, c is 70mm, d is 50mm,
e and f are each 5 mm. In addition, in Example 4, EVA was applied only to the surface.
was coated, and only the surface material was laminated.

【table】

[Table] From the results in Table 2, it was confirmed that a laminate with clear weld lines could be obtained according to the method of the present invention. That is, in Examples 1 to 3 of the three-layer structure using ordinary flexible polyurethane foam, 6
~10 mm, and in Example 4 with a two-layer structure, a laminate with a step of 3 mm or more was obtained, and especially in Example 5 with a three-layer structure using a net-like foam without a cell membrane, a step with a step of 15 mm or more was obtained. A laminate was obtained.

[Brief explanation of drawings]

FIG. 1 is a partially cross-sectional schematic diagram showing the apparatus used for manufacturing the laminate of the example, and FIG. 2 is a back view showing a template of the hot press apparatus of the same apparatus. 1... Soft polyurethane foam, 6... Front side material, 7... Back side material, 8... Heat press device.

Claims (1)

[Claims] 1. A method in which a soft polyurethane foam and a face material are heat-pressed using a mold having an uneven shape to laminate and integrate the face material on one or both sides of the soft polyurethane foam, wherein the soft polyurethane foam has air permeability. The amount of air passing through a Frazier type tester based on the JIS-L1004-1972 cotton fabric testing method is 40cm ³ /cm ² /second or more, and the surface of the soft polyurethane foam on which the above surface material is to be laminated is made of thermoplastic material. 40 to 150 g/m ² of resin composition per laminated surface
The coating is applied in advance so that it penetrates 1 mm or more into the inside of the soft polyurethane foam surface with a coating amount of 10 to 70℃ lower than the melting temperature of polyurethane foam, and -40℃ to +50℃ lower than the hot pressable temperature of soft polyurethane foam.
A method for manufacturing a laminate, characterized in that the temperature is in the range of °C. 2. The manufacturing method according to claim 1, in which a mesh-like flexible polyurethane foam without a cell membrane is used. 3 Temperature at which a soft polyurethane foam can be hot-pressed (a 20 mm thick soft polyurethane foam is compressed to 4 mm and held for 120 seconds, after releasing the press 24
3. The manufacturing method according to claim 1 or 2, using a material having a minimum pressing temperature of 200° C. or less for a foam thickness of 4.5 mm or less. 4 Softening point as a thermoplastic resin composition is 60 to 180
Claim 1 using a temperature range of ℃
The manufacturing method according to any one of items 1 to 3. 5. The manufacturing method according to any one of claims 1 to 4, wherein the non-permeable portion of the thermoplastic resin composition of the flexible polyurethane foam has a thickness of 30 mm or less. 6. Use natural fiber woven or non-woven fabric or synthetic resin film, leather, woven fabric, or non-woven fabric as the surface material, heat press from the surface material side, and laminate the surface material on one side of the soft polyurethane foam. Claims 1 to 5
The manufacturing method described in any of the paragraphs. 7 A woven fabric or non-woven fabric made of natural fibers or a synthetic resin film, leather, woven fabric or non-woven fabric is used as the front side material, and a woven fabric or non-woven fabric made of natural fiber, a synthetic resin film, leather, etc. is used as the back side material.
Any one of claims 1 to 6, in which a woven fabric, a non-woven fabric, or a self-supporting plate material is used, and the face material is laminated on both sides of the soft polyurethane foam by hot pressing from the front side material side. Manufacturing method described. 8. The manufacturing method according to claim 6 or 7, wherein the surface material has an elongation rate of at least 50% or more in one axial direction. 9 As a surface material, the elongation rate is 50 in both axial directions.
% or more of the manufacturing method according to claim 8. 10. The manufacturing method according to any one of claims 6 to 9, using a surface material having a melting temperature of 160 to 240°C. 11. The manufacturing method according to any one of claims 6 to 10, using a material whose surface is brushed or flocked. 12 As a back side material, the elongation rate is in both axial directions.
The manufacturing method according to claim 7, using 10% or less of film, leather, woven fabric or non-woven fabric. 13. The manufacturing method according to any one of claims 1 to 12, wherein the thickness of the flexible polyurethane foam in the welded portion of the laminate is 20% or less of the thickness of the original flexible polyurethane foam. 14 After removing the hot press mold, the thermoplastic resin composition is further pressed by a mold having a temperature lower than the softening point of the thermoplastic resin composition before it hardens. The manufacturing method according to any one of Clause 13.