JP2015155146A - Laminate production method, laminate and cushion material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate which is excellent in bond strength between a cushion layer and a substrate layer of the laminate and can suppress separation between the cushion layer and the substrate layer.

SOLUTION: A method of producing a laminate is composed of a cushion layer laminated integrally on a substrate layer and includes (1) a step of supplying a liquid raw material for polyurethane foam onto a substrate layer composed of a foam particle molding which is formed with polyolefin resin foam particles having through hole and fused mutually, includes cavities communicating with the outside and has a total porosity (A) of 10 vol.% or higher and (2) a step of foaming the liquid raw material for polyurethane foam to form a cushion layer of the polyurethane foam on the substrate layer and solidifying part of the polyurethane foam within cavities positioned on the surface side of the substrate layer so as to laminate the substrate layer integrally with the cushion layer.

COPYRIGHT: (C)2015,JPO&INPIT

Description

  The present invention relates to a laminate manufacturing method, a laminate, and a cushion material.

  For example, as described in Patent Document 1, conventionally, a laminate formed by laminating a plurality of layers made of different materials has been used for, for example, a seat used in an automobile, etc. A laminate in which a cushion layer made of a material having cushioning properties and a base material layer made of a lightweight material having higher strength and rigidity than the cushion layer is known. As a material constituting the cushion layer, for example, a soft polyurethane foam or the like is used, and the cushioning layer is configured so that the seating comfort when the passenger is seated, the feeling of holding the waist, and the like are good.

  On the other hand, as a material constituting the base material layer, for example, a material formed using a styrene resin, an ethylene resin, a propylene resin, or the like is used, and the strength and rigidity of the cushion layer are supplemented. It is possible to reduce the weight of itself. Thus, it becomes possible to obtain the laminated body which has a composite characteristic by laminating | stacking the cushion layer and base material layer which consist of a different raw material.

  As a method for forming such a laminate, a method using a molding die is known. As described in Patent Document 1, for example, in a molding space formed in a molding die, a member constituting a base layer formed in advance is arranged, and the molding space in which the member is arranged The cushion layer can be directly molded (laminated) on the surface of the base material layer by filling the cushion layer material (such as a liquid material for polyurethane foam) into the cushion layer.

  Furthermore, in Patent Document 1, a cushion layer and a base in a laminate in which a cushion layer made of urethane foam and a base material layer made of a resin having poor adhesion to urethane foam such as a propylene-based resin foam are laminated. Studies have also been made to suppress separation between the material layers. Specifically, in Patent Document 1, when forming the foreign material layer, the contact area with the foreign material layer on the surface of the molded body is heated at a temperature of 80% or more of the softening temperature of the molded body, thereby making contact. There has been proposed a method for manufacturing a laminate in which expandable resin particles forming a region are softened and expanded to form irregularities in a contact region, and a different material layer is formed so as to enter the concave portion of the irregularity.

  However, even in the laminated body manufactured by the manufacturing method of Patent Document 1, the adhesive strength between the layers constituting the laminated body is not always sufficient, and it is difficult to reliably suppress peeling between the layers. For example, if separation occurs between the cushion layer and the base material layer of a laminate used for a seat of an automobile or the like, the passenger's sitting comfort and hold feeling are reduced, or the rubbing sound between the layers due to separation is generated. There are problems, such as occurring.

  The present invention has been made in view of the circumstances as described above, and has excellent bonding strength between a cushion layer and a base material layer of a laminate, and can prevent peeling between the cushion layer and the base material layer. It is an object to provide a body and a manufacturing method thereof. Furthermore, it is an object to provide a cushion material using this laminate.

In order to solve the above-described problems, the laminate manufacturing method of the present invention is a laminate manufacturing method in which a cushion layer is laminated and integrated on a base material layer, and includes the following steps:
(1) Foamed particle molded body which is formed by fusing polyolefin-based resin expanded particles having through-holes, has voids communicating with the outside, and has a total porosity (A) of 10% by volume or more. Supplying a liquid polyurethane foam raw material onto the base material layer; and (2) foaming the liquid polyurethane foam raw material to form a polyurethane foam cushion layer on the base material layer. The method further comprises a step of solidifying a part of the polyurethane foam in the space on the surface side of the base material layer and laminating and integrating the base material layer and the cushion layer.

  In this method for producing a laminate, the bending fracture strength of the base material layer before supplying the liquid polyurethane foam raw material in the step (1) is preferably 0.1 Mpa or more.

  In this method for producing a laminate, the substrate layer before supplying the liquid polyurethane foam raw material in the step (1) has a porosity (B) of the surface layer portion of 20% by volume or more and an overall porosity. The ratio (A / B) of the porosity (B) of the surface layer part to (A) is more preferably 0.6 to 1.2.

  The laminate of the present invention is formed by fusing polyolefin resin particles having through-holes, and a cushion layer made of polyurethane foam is formed on a base material layer made of a foamed particle molded body having voids communicating with the outside. It is a laminated body that is laminated and integrated, and is characterized in that a part of the polyurethane foam enters and solidifies at least in the gap located on the surface side of the base material layer.

  The cushion material of the present invention is characterized by including the laminate.

  The cushion material is preferably for a vehicle seat.

  According to the method for manufacturing a laminate of the present invention, it is possible to obtain a laminate that is excellent in the bonding strength between the cushion layer and the base material layer of the laminate and in which peeling between the cushion layer and the base material layer is suppressed. Moreover, since the peeling of the cushion layer and the base material layer is suppressed, the laminate of the present invention can be used as a material (cushion material) for a seat such as an automobile.

It is the schematic diagram which illustrated one form of the cylindrical polyolefin resin particle.

The method for producing a laminate of the present invention is a method for producing a laminate in which a cushion layer is laminated and integrated with a base material layer,
The following steps:
(1) Foamed particle molding in which polyolefin resin foamed particles having through-holes are fused and formed, have voids communicating with the outside, and have a total porosity (A) of 10% by volume or more A step of supplying a liquid polyurethane foam raw material on the body base layer; and (2) foaming the liquid polyurethane foam raw material to form a polyurethane foam cushion layer on the base material layer. And a step of solidifying a part of the polyurethane foam in the space on the surface side of the base material layer and laminating and integrating the base material layer and the cushion layer.

  Hereinafter, each step will be described.

  In the step (1), the polyolefin resin expanded particles having through holes are formed by fusing with each other, and have voids communicating with the outside, and the total void ratio (A) is 10% by volume or more. A liquid polyurethane foam raw material is supplied onto the base material layer made of the expanded particle molded body.

  The base material layer is formed of a foamed molded article having voids communicating with the outside, in which polyolefin resin foamed particles having through holes are fused to each other.

  For example, Patent Document 2 (Japanese Patent Laid-Open No. 08-108441, Patent No. 2805286), Patent Document 3 (Japanese Patent Laid-Open No. 07-137063, Patent No. 2) are used as foamed molded articles made of polyolefin resin expanded particles forming the base material layer. 3377575), Patent Document 4 (Japanese Patent Laid-Open No. 2012-126816) and the like, and can be produced by a conventionally known method proposed by the present applicant.

  Specifically, for example, first, a polyolefin-based resin as a base resin is melt-kneaded with an extruder, and then extruded into a cylindrical strand shape. Cylindrical polyolefin resin particles having through holes can be produced by a method such as cooling after cutting. At this time, in order to select the one having a slit similar to the cross-sectional shape of the desired polyolefin-based resin particle at the molten resin outlet of the extruder die or to maintain the cylindrical shape, the cylindrical strand inside the slit What provided the pressure adjustment hole for maintaining the pressure of a hole part to a normal pressure or more can be used.

  Examples of polyolefin resins include ethylene-propylene block copolymers, ethylene-propylene random copolymers, propylene-butene random copolymers, ethylene-propylene-butene terpolymers, polypropylene resins such as homopolypropylene, low density polyethylene, medium density polyethylene, Polyethylene resins such as high-density polyethylene, linear low-density polyethylene, ultra-low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, and ionomer resin in which the molecules of the ethylene-methacrylic acid copolymer are crosslinked with metal ions. Or one or more of polybutene, polypentene, and the like. Among these, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, ultra-low-density polyethylene, polypropylene, polybutene, and ethylene-propylene are good in terms of recoverability after compression of the foamed molded article. Preferred are copolymers, propylene-butene copolymers, ethylene-butene-propylene terpolymers and the like.

  The polyolefin resin may be used in an uncrosslinked state, but may be used after being crosslinked with peroxide or radiation. However, non-crosslinked ones are preferable in terms of the number of production steps and recyclability.

  Next, the polyolefin resin particles are dispersed in a dispersion medium in the presence of a foaming agent in a closed container, and heated to a temperature equal to or higher than the softening temperature of the polyolefin resin particles to impregnate the resin particles with the foaming agent. Thereafter, the container is once opened, and the polyolefin resin particles and the dispersion medium are simultaneously placed in a lower pressure atmosphere than the container (usually under atmospheric pressure) while maintaining the container pressure at a pressure higher than the vapor pressure of the blowing agent. The polyolefin resin foam particles having through-holes can be obtained by releasing the resin foam into the polyolefin resin particles.

  As the foaming agent used for obtaining polyolefin resin particles, propane, isobutane, butane, isopentane, pentane, cyclopentane, hexane, cyclobutane, cyclohexane, chlorofluoromethane, trifluoromethane, 1, 2, 2, 2 are usually used. -Volatile organic blowing agents such as tetrafluoroethane, 1-chloro-1,1-difluoroethane, 1,1-difluoroethane, 1-chloro-1,2,2,2-tetrafluoroethane, nitrogen, carbon dioxide, Inorganic gas-based foaming agents such as argon and air can be mentioned. Among them, an inorganic gas-based foaming agent that does not destroy the ozone layer and is inexpensive is preferable, and nitrogen, air, and carbon dioxide are particularly preferable. Moreover, it can also be used in the mixed system of 2 or more types of the said foaming agent, and when the foaming magnification improvement effect is considered, the mixed foaming agent of a carbon dioxide and butane can be used.

  The dispersion medium used for obtaining the polyolefin resin expanded particles may be any dispersion medium that does not dissolve the resin particles. Examples of such a dispersion medium include water, ethylene glycol, glycerin, methanol, ethanol, and the like. But usually water is used.

  In addition, when the polyolefin resin particles are dispersed in a dispersion medium and heated to the foaming temperature, an anti-fusing agent can be used to prevent the resin particles from fusing with each other.

  Furthermore, the polyolefin resin particles may be colored by adding a coloring pigment or dye such as black, gray, or brown.

  The polyolefin resin expanded particles having through-holes are, for example, cylindrical, and (a) the outer peripheral shape and the hollow portion are both circular, and (b) both the outer peripheral shape and the hollow portion. (C) the outer peripheral shape is circular and the hollow portion is polygonal, (d) the outer peripheral shape is polygonal and the hollow portion is circular, (e) the above (a ) To (d) are joined to each other on the outer periphery thereof.

  Moreover, the external shape of the cylindrical polyolefin resin expanded particles, the dimensions of the hollow portion, and the like can be designed as appropriate. For example, taking a case where the cylindrical polyolefin-based resin expanded particles having through-holes have a circular outer shape and a hollow portion, the cylindrical polyolefin is illustrated as illustrated in the schematic diagram of FIG. The outer diameter D of the resin particles 1 is preferably 2 to 6 mm, the inner diameter d (the diameter of the hollow portion P) is preferably 1 to 5 mm, and the length L is preferably 2 to 6 mm. When the dimension of the cylindrical polyolefin resin particles is within this range, the bonding strength between the cushion layer and the base material layer of the laminate can be further increased as described later. Furthermore, in this case, it is more preferable that L / D = 0.8 to 1.2, and the inner diameter d is 1.5 mm or more, whereby the bonding strength between the cushion layer and the base material layer can be further increased. .

  And, for example, a polyolefin resin having a through hole is prepared by filling the mold with polyolefin resin foamed particles having a through hole manufactured by such a method, and heating the mold to a predetermined temperature to mold in the mold. A foamed particle molded body in which the foamed particles are fused to each other can be obtained. The molding conditions can be appropriately set in consideration of the use of the laminate. This foamed particle molded body constitutes the base material layer of the laminate of the present invention.

  This foamed particle molded body (base material layer) has a void communicating with the outside. The voids in the foamed particle molded body (base material layer) include voids due to through holes in the tubular polyolefin resin foam particles and voids due to gaps formed between a plurality of fused polyolefin resin foam particles. It is out.

  And the whole porosity (A) of a foaming particle molded object (base material layer) is 10 volume% or more. If the total porosity (A) is less than 10% by volume, it is difficult to ensure the bonding strength between the cushion layer and the base material layer. On the other hand, if the total porosity (A) exceeds 40% by volume, the mechanical strength of the foamed particle molded body itself may be insufficient. From such a viewpoint, it is preferable that the whole porosity (A) of a foamed particle molded object is 12 to 35 volume%, More preferably, it is 15 to 30 volume%.

  Further, the porosity (B) of the surface layer portion of this foamed particle molded body (base material layer) (the porosity of the region from the surface to 3 mm in the thickness direction) is preferably 20% by volume or more. In the present invention, the surface side of the base material layer refers to a surface on which a cushion layer made of polyurethane foam is laminated as a laminate.

  And the ratio (A / B) of the porosity (B) of the surface layer part to the total porosity (A) is preferably 0.6 to 1.2, more preferably 0.8 to 1.2, and 0.9 to 1.2. More preferably. When the ratio (A / B) of the porosity (B) of the surface layer portion to the overall porosity (A) is within this range, the cushion of the laminate is not reduced as described later without reducing the mechanical strength of the laminate. The bonding strength between the layer and the base material layer can be further increased.

Further, the bending fracture strength of the foamed particle molded body (base material layer) is preferably 0.1 MPa or more, and the density is preferably 0.02 to 0.06 g / cm ³ . When the bending fracture strength and density of the foamed particle molded body (base material layer) are within this range, the strength of the laminate can be reliably ensured.

  Next, a liquid polyurethane foam raw material is supplied onto the base material layer of the foamed particle molded body disposed in the mold. At this time, a part of the liquid polyurethane foam raw material may enter at least the gap located on the surface side of the base material layer.

  As the raw material for the liquid polyurethane foam, known materials can be used as appropriate, and polyurethane and various foaming agents can be included. Also, the amount of liquid polyurethane foam raw material to be supplied can be appropriately set.

  In step (2), a liquid polyurethane foam raw material is foamed to form a polyurethane foam cushion layer on the base material layer, and part of the polyurethane foam is solidified in the voids on the surface side of the base material layer. The base material layer and the cushion layer are laminated and integrated.

  At this time, when a part of the polyurethane foam is pushed into the gap of the base material layer by the pressure at the time of foaming the raw material for the polyurethane foam, or when the raw material for the polyurethane foam is supplied onto the base material layer, the base material layer When the polyurethane foam raw material that has entered into the voids foams, a part of the polyurethane foam enters into the voids of the base material layer and solidifies. Furthermore, since the polyolefin resin foam particles having through-holes are fused to each other in the base material layer, polyurethane foam enters the voids formed by the through-holes of the foam particles. It becomes difficult to destroy the structure. Furthermore, since the voids of the foamed particle molded body are formed by complicatedly connecting the through holes of the foamed particles and the gaps between the foamed particles, the base material layer and the polyurethane foam have a high contact area and a complicated shape. Will be in close contact. Therefore, the base material layer and the polyurethane foam cushion layer are laminated and integrated with high bonding strength. In addition, the conditions for foaming the raw material for polyurethane foams can be set as appropriate.

  As described above, the laminate of the present invention is formed of a polyurethane resin on a base material layer formed of a foamed particle molded body having a void that communicates with the outside and is formed by fusing polyolefin-based resin expanded particles having through holes. In the laminated body in which cushion layers made of foam are laminated and integrated, polyurethane foam has entered and solidified into the voids of the base material layer located at least on the surface side. For this reason, it is excellent in the joint strength of the cushion layer of a laminated body, and a base material layer, and peeling with a cushion layer and a base material layer can be suppressed reliably.

  Therefore, the laminate of the present invention can be effectively used as various cushion materials. Specifically, for example, it can be used for various applications where cushioning is desired, such as seats for vehicles such as automobiles, motorcycles, aircraft, trains, sofas, chairs, etc. Generation of a rubbing sound associated with peeling between the cushion layer and the base material layer is also reliably suppressed.

  The manufacturing method of a laminated body of this invention, a laminated body, and a cushion material are not limited to the above form.

  Hereinafter, the manufacturing method of a laminated body of this invention and a laminated body are demonstrated in more detail with an Example.

<1> Foamed particle molded body As a foamed particle molded body constituting the base material layer, it has through holes having a bulk density of 24 kg / m ³ , a true density of 53 kg / m ³ , an average particle weight of 1.5 mg, and an average L / D = 1.0. The substantially cylindrical polyolefin resin expanded particles were molded in-mold and fused (molded bodies 1 to 4). In addition, an in-mold molded product of substantially cylindrical resin foam particles having an apparent density of 24 kg / m ³ , an average particle weight of 2 mg and no through holes was also prepared (molded bodies 5 and 6). The molded body 5 is formed in the shape of a void in which voids are formed between the fused resin foam particles, but since the resin foam particles used do not have through holes, the molded body 5 is compared with the molded bodies 1-4. Thus, the overall porosity is small, and the shape of the void is not complicated. On the other hand, the molded body 6 has no voids formed between the fused resin foam particles.

  The porosity of the foamed particle molded body was adjusted by adjusting the pressure and heating time of the heating steam at the time of in-mold molding.

  And about this foamed particle molded object 1-6, the porosity (B) and the whole porosity (A) of each surface layer part were measured. The porosity is calculated by the following formula.

Porosity (volume%) = [(X−Y) / X] × 100
Here, X is the apparent volume (cm ³ ) of the molded body, and C is the true volume (cm ³ ) of the molded body. The apparent volume X represents the volume calculated from the outer dimensions of the foam molded article, and the true volume Y represents the substantial volume excluding the voids of the foam molded article. The true volume Y can be known by measuring the increased volume when the foamed molding is submerged in a liquid (for example, alcohol).

  In addition, the surface layer part porosity (B) is the porosity of the area | region to 3 mm from the surface to the thickness direction.

  The results are shown in Table 1.

<2> Preparation of Laminate Foamed particle compacts 1 to 4 are placed in a mold as a base layer, and a liquid polyurethane foam raw material (Nisshinbo Chemical Co., Ltd .: Airlight Foam) is supplied thereon. And cushion layers were laminated to produce laminates 1 to 4 of the present invention. Similarly, the polyurethane foam raw material was supplied and foamed using the molded bodies 5 and 6 as the base material layer, and the cushion layers were laminated to produce the laminated bodies 5 and 6.

  The laminates 1 to 6 were cut into a size of 50 mm × 50 mm, and the upper and lower surfaces were bonded to the SUS plate. The adhesive was a medmedine PPK1000 so as not to peel from the SUS surface, and a tensile test was conducted with a universal testing machine (Tensilon) in an environment of 23 ° C. and 50% RH. The tensile speed was 10 mm / min.

  The results are shown in Table 2.

  As shown in Table 2, the laminated bodies 1 to 4 of the present invention are superior to the laminated bodies 5 and 6 in the maximum load (N), and the bonding strength between the base material layer and the cushion layer is good. It was confirmed that there was.

  1 Polyolefin resin foamed particles

JP 2012-171104 A Japanese Patent Laid-Open No. 08-108441 Japanese Unexamined Patent Publication No. 07-137063 JP 2012-126816 JP

Claims (6)

A method for producing a laminate in which a cushion layer is laminated and integrated on a base material layer,
The following steps:
(1) Foamed particles having polyolefin resin foamed particles having through holes fused to each other, having voids communicating with the outside, and an overall porosity (A) of 10% by volume or more A step of supplying a liquid polyurethane foam raw material onto a base material layer comprising a molded body; and (2) forming a cushion layer of polyurethane foam on the base material layer by foaming the liquid polyurethane foam raw material. And a step of solidifying the polyurethane foam in a gap located on the surface side of the base material layer to laminate and integrate the base material layer and the cushion layer. .   The method for producing a laminate according to claim 1, wherein the bending fracture strength of the base material layer before supplying the liquid polyurethane foam raw material in the step (1) is 0.1 MPa or more.   The porosity (B) of the surface layer portion of the base material layer before supplying the liquid polyurethane foam raw material in the step (1) is 20% by volume or more, and the porosity of the surface layer portion with respect to the entire porosity (A) The ratio (A / B) of (B) is 0.6-1.2, The manufacturing method of the laminated body of Claim 1 or 2 characterized by the above-mentioned.   Polyurethane-based resin particles having through-holes are fused to each other, and a cushion layer made of polyurethane foam is laminated and integrated on a base material layer made of a foamed particle molded body having voids communicating with the outside. A laminate, wherein the polyurethane foam enters and solidifies at least in the gaps located on the surface side of the base material layer.   A cushioning material comprising the laminate according to claim 4. The cushioning material according to claim 5, wherein the cushioning material is for a vehicle seat.

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