JP2849936B2 - Manufacturing method of laminated material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Object of the Invention (Industrial Application Field) The present invention relates to a ceiling material of an automobile, a door trim, a rear shell, a seat back, a trunk surrounding member, a floor, a ceiling material of a building, and a wall material. The present invention relates to a method for producing a laminated shape used in various applications such as cosmetic containers and the like.

(Prior art) Conventionally, materials that can withstand temperatures of 100 ° C or more, such as resin felt filled with phenol / aldehyde condensed resin and fibers, foam synthetic resin, polypropylene composite material, and polypropylene cardboard, have been used as interior materials for automobiles. Have been.

Among these materials, resin felt is excellent in rigidity, dimensional stability and shielding properties, but has drawbacks such as poor molding workability, impact resistance and lightness.

Further, a foamed synthetic resin, for example, a foamed polystyrene sheet, is excellent in softness, but has drawbacks in poor moldability and bending resistance, and has a problem in appearance and texture after molding.

Further, the polypropylene composite material is excellent in rigidity, but has a drawback that molding workability, impact resistance and dimensional stability are inferior.

Further, polypropylene corrugated cardboard is excellent in rigidity and light weight, but has poor drawability, and has drawbacks in that the strength is directional due to the use of a corrugated member.

In short, the conventional interior materials have not been able to satisfy all the properties required for the interior materials, that is, rigidity, appropriate flexibility, dimensional stability, moldability, and the like.

On the other hand, a softening temperature of 100 to 130
It is also known to apply or impregnate an aqueous emulsion of a thermoplastic resin at ℃, and then heat and dry to remove moisture to form a nonwoven fabric which can be molded, and further heat and press-mold the resulting nonwoven fabric to produce interior materials for automobiles. I was The interior material manufactured by such a method is excellent in moldability and has an advantage that it can be applied to a place having a complicated shape.However, the fixing of the nonwoven fabric fiber is entangled with the fibers by needle punching,
Since those of emulsion resin by attachment of the fiber, apparent density of the nonwoven fabric which emulsion is coated and impregnated to high 0.08~0.13g / cm ³ and bulk, not sufficient filling effect by emulsion resin, shielding There was a drawback that it was inferior in properties, and the molded product had insufficient rigidity. In order to improve the drawback, attempts have been made at the time of hot press molding, for example, by bonding and melting and bonding polyethylene sheets, but an increase in the number of steps and an increase in the weight of the laminated molded product cannot be avoided.

In addition, polyethylene or ethylene
A backing coating composition containing a thermoplastic resin powder such as vinyl acetate copolymer (but not described using polystyrene particles) has been proposed (Japanese Patent Publication No. 57-34391), and the backing coating composition is used for carpet. If it is, the sticking property of the fibers of the obtained carpet is improved, and the carpet can be given thermoformability. However, the publication discloses that the heat deformation temperature of the thermoplastic resin powder in the backing coating agent is 80 ° C. or less, and that the particle diameter is desirably 100 μm or less.
Carpets to which such a backing coating agent has been applied are not sufficiently satisfactory in terms of heat retention and shielding properties after molding.

Further, the present inventors, as a material having excellent moldability, rigidity and shielding properties, and moderate lightness and heat-resistant mold retention, as a backing agent, expandable styrene resin particles and a resin aqueous emulsion. A laminated material having a structure in which the backing layer is used and sandwiched by a base fabric has been proposed (Japanese Patent Application Laid-Open No. 63-139732). Then, the method for producing the laminated material is such that a resin aqueous emulsion having a solid content of 100 parts by weight and an expandable styrene-based resin particle having a heat deformation temperature of 150 ° C. or more are mixed on a base fabric (A) of 150-150 ° C. or more. A backing coating agent mixed at a ratio of 700 parts by weight is applied, and then a base cloth (B) made of a material having a heat deformation temperature of 150 ° C. or higher is laminated on the coating layer to form a laminate. After compressing the laminate from one or both sides of the body and impregnating a part of the coating agent into the base fabric (B), the base fabric (A) is heated to a temperature equal to or higher than the softening point of the expandable styrene resin particles. ) And (B) are heated at a temperature lower than the thermal deformation temperature of the material, thereby expanding the expandable styrene resin particles and drying the aqueous resin emulsion to form the base fabrics (A) and (B). This is based on a method of forming a laminate having a foam layer between them. However, in this method, since the drying of the emulsion and the foaming of the expandable styrene resin particles are simultaneously performed, the allowable range of the temperature in the drying furnace is narrow, and it is necessary to perform strict temperature control. Is troublesome, and the productivity is poor.

(Problems of the Invention) The present invention is excellent in bending strength, water impermeability, heat resistance, elasticity, mold fidelity, shielding properties and shape retention, and has a laminated material having any properties from flexibility to rigidity. Is intended to provide a method which can be easily manufactured without requiring complicated process control.

That is, the method for producing a laminated material shaped article of the present invention comprises, on a fibrous base cloth (A) made of a material having a heat deformation temperature of 130 ° C. or more, a styrene monomer of 20 to 80% by weight and other An aqueous emulsion of a styrene copolymer having a minimum film-forming temperature of not more than 60 ° C. obtained by emulsion polymerization of 80 to 20% by weight of a vinyl monomer is 100 parts by weight in terms of solid content, and an average particle size is 0.05 to 0.5%. mm of non-expandable styrene-based polymer particles in a solid content of 50 to 700 parts by weight, and then apply a backing coating agent, and then heat deformation temperature of the material of the fibrous base fabric (A) Heating and drying at a lower temperature to obtain a resin-coated base fabric, and then obtaining the resin-coated base fabric at a temperature equal to or higher than the softening temperature of the non-expandable styrene-based polymer particles and the fibrous base fabric (A). This is a method characterized by heating (secondary heating) under conditions where the material does not thermally deform.

The fibrous base fabric (A) made of a material having a heat deformation temperature of 130 ° C. or higher in the present invention is to be a surface layer material of a molded product of a laminated product, and preferably has a cosmetic property. Examples include tufted carpets, woven fabrics, needle punched carpets, nonwoven fabrics such as synthetic leather, nonwoven fabrics made by screen printing, and backings of these base fabrics.

Examples of the material of the fibrous base fabric (A) include natural fibers such as wool and silk, glass fibers, and synthetic resin fibers such as nylon, polyethylene terephthalate, polypropylene, and polyacrylonitrile.

The fibrous base fabric (A) of the present invention has a heat deformation temperature of 20 ° C. lower than the softening temperature of the non-expandable styrene-based polymer particles in the backing agent in order to prevent heat deformation during hot pressing.
A higher one is desirable. In addition, the fibrous base fabric (A)
Has a basis weight of 50 g / m ² or more, and preferably 80 g / m ² or more in order to prevent the aqueous emulsion of the copolymer from seeping into the skin.

The backing coating composition of the present invention is a styrene-based monomer having a minimum film-forming temperature of 60 ° C. or lower, obtained by emulsion polymerization of 20 to 80% by weight of a styrene monomer and 80 to 20% by weight of another vinyl monomer. 100 parts by weight of the aqueous emulsion of the copolymer in terms of solid content, non-expandable styrene polymer particles having a particle size of 0.05 to 0.5 mm in a solid content of 50 to 700 parts by weight, preferably 100 to 100 parts by weight.
It is blended at a ratio of 500 parts by weight.

If the amount of the styrene-based monomer in the styrene-based copolymer is too small (in other words, if the amount of other vinyl monomers is too large), the copolymer aqueous emulsion and the non-foamable styrene-based polymer particles The compatibility becomes poor, and the non-expandable styrene-based polymer particles are easily separated in the coating layer. Conversely, if the amount of the styrene-based monomer is too large (in other words, if the amount of other vinyl monomers is too small), the minimum film-forming temperature of the styrene-based copolymer emulsion tends to exceed 60 ° C, The elasticity of the matrix of the coating layer before the secondary heating (before the compression heating molding) is reduced, and the coating layer becomes brittle.

In addition, the average particle size of the non-expandable styrene-based polymer particles is 0.
If it is less than 05 mm, it will not be able to remain on the surface of the base fabric when it is applied to the fibrous base fabric (A), and will not penetrate into the inside of the base fabric. If the particle size exceeds 0.5 mm, the coating layer before hot press molding (before secondary heating) becomes brittle. The styrene-based polymer particles having an average particle size in the range of 0.05 to 0.5 mm used in the present invention are produced by ordinary suspension polymerization. It is also possible to use particles having a gas content of such a particle system range that is obtained as a raw product and has substantially no foaming property.

If the proportion of the non-foamable styrene-based polymer particles to the styrene-based copolymer aqueous emulsion is too small, the thermoformability of the laminated material obtained by coating and drying is deteriorated, and after secondary heating. In this case, the synthesis and heat-resistant shape-retaining properties of the laminated material-imposed product of the above are reduced, and the shielding property is also deteriorated. vice versa,
If the proportion of the non-expandable styrene-based polymer particles is too large, the coating layer after secondary heating and after shaping becomes brittle.

In addition, the coating agent comprising a mixture of the styrene-based copolymer aqueous emulsion and the styrene-based polymer particles includes a film-forming aid, a drying accelerator, an organic solvent, a dispersant, a wetting agent, a defoaming agent,
A foaming agent, a heat-sensitive agent, a coloring agent, a filler and the like can be blended. The minimum film-forming temperature of the aqueous styrene copolymer emulsion in the present invention is a value of a system containing a plasticizer and a film-forming auxiliary when they are blended.

As the styrene monomer in the present invention, styrene, α-methylstyrene and the like are used.

In addition, other vinyl monomers other than the styrene-based monomer include lower alkyl esters of acrylic acid (1-8 carbon atoms in the alkyl group), lower alkyl esters of methacrylic acid (1-8 carbon atoms in the alkyl group), Butadiene, acrylonitrile, vinyl acetate, vinylidene chloride, acrylic acid,
Methacrylic acid, acrylamide, methacrylamide, hydroxyethyl (meth) acrylate, methylol (meth) acrylamide, diacetone acrylamide, and the like are used. Particularly, from the viewpoint of weather resistance, lower alkyl acrylate and lower alkyl methacrylate are preferred.

Styrene copolymer emulsion in the present invention,
The resin solid content concentration is usually 30 to 60% by weight, and the dispersed particle diameter is usually 0.05 to 1.0 µ.

Examples of the non-expandable styrene polymer particles include polystyrene, styrene / α-methylstyrene copolymer, styrene / α-methylstyrene / acrylonitrile copolymer, and styrene / α-methylstyrene / acrylonitrile / butyl methacrylate. Particles such as a copolymer and a styrene / methyl methacrylate copolymer are exemplified. These non-expandable styrene-based polymer particles are excellent in mixing property with the aqueous emulsion of the styrene-acrylic acid lower alkyl ester copolymer, and the non-expandable styrene-based polymer particles By blending in the above, the heat press molding of the laminate can be facilitated, and the obtained laminated material molded article can be given shape retention and rigidity. The softening temperature of the non-expandable styrene polymer particles is preferably in the range of 100 to 120 ° C.

Next, the method for producing a laminated material shaped article of the present invention will be described in detail. First, the aqueous emulsion of the styrene-based copolymer and the non-foamed A backing coating agent containing a blend of hydrophilic styrene-based polymer particles is applied, and the primary heating is used to produce a fibrous base fabric (A)
A non-expandable styrene-based polymer particle layer is formed on the surface of the substrate, and the styrene-based copolymer emulsion particles are impregnated in the layer of the fibrous base fabric (A). Next, the fibrous base fabric to which the backing coating agent has been applied is heated and dried (primary heating) at a temperature lower than the heat deformation temperature of the base fabric material to obtain a resin-coated base fabric. By heating (secondary heat compression molding) the coated base fabric at a temperature equal to or higher than the softening temperature of the non-expandable styrenic polymer particles and under conditions where the fibers of the base fabric (A) are not thermally deformed. A backing layer on the surface of the base fabric where the polymer and the non-expandable styrenic polymer particles are sufficiently adhered, and a fibrous base fabric in which the copolymer particles are dispersed inside the fiber layer are laminated in a laminate. Manufacture bonded excipients.

The application of the backing coating agent is performed using a spray, a brush, a foam coating machine, a roll, or the like, and the application amount of the backing coating agent is 100 to 1700 g / m ² (solid content), preferably 300 11300 g / m ² . The foam coating method is particularly preferred from the viewpoint of ease of adjustment of coating workability, coating amount and coating thickness.

Drying of the coated backing coating agent can be performed by any method. For example, there are various drying methods using a heating cylinder, an infrared heater, a hot air dryer, a suction dryer, and the like. The method using a machine is common.

As a secondary heating method of the resin-coated base fabric, a two-stage method of heating usually using an infrared heater or the like and subsequently pressing, or a one-stage method of simultaneously performing heating and compression using a heating roll is used. Although the latter one-step method can be used, by connecting to a backing coating heating dryer,
The process from backing coating to heating and compression can be performed all at once in an inline manner, which is advantageous.

(Examples and the like) Hereinafter, examples and comparative examples will be described in detail.

Example 1 80% by weight of polyester fiber and 20 of polypropylene fiber
Needle punch carpet (weight per unit weight 200g)
/ m ² ), the following backing coating agent in solid content of 500g / m ²
The foam was applied so that

The backing coating agent is a styrene (35% by weight) -acrylonitrile (15% by weight) -butyl acrylate (45% by weight) -acrylic acid (3% by weight) -acrylamide (2% by weight) copolymer (minimum film formation) Solid content 50% by weight at 30 ° C)
And the non-expandable polystyrene particles having an average particle size of 0.2 mm were prepared by mixing 300 parts by weight of the latter with 200 parts by weight of the former in terms of solid content.

Next, the needle-punched carpet coated with the backing coating agent was placed on both sides of the coated surface and the opposite surface by 130
The film was heated and dried with hot air of 15 ° C. for 15 minutes to remove water, thereby obtaining a resin-coated cloth. This resin coated cloth has a needle punch carpet thickness of about 2 mm and a backing coating layer of about 0.5 mm
Met.

Next, the resin coated cloth was heated in a far-infrared furnace at 180 ° C. for 60 seconds to sufficiently soften the copolymer resin and polystyrene resin particles of the backing coating agent layer, and then used a cooling press mold. Then, it was pressed at a pressure of 20 kg / cm ² for 1 minute to form a carpet for an automobile floor.

Comparative Example 1 As the backing coating agent, only an aqueous emulsion having a solid content of 50% by weight of the same styrene-acrylonitrile-butyl acrylate-acrylic acid-acrylamide copolymer used in the backing coating agent of Example 1 was used. A carpet for an automobile interior floor was manufactured in the same manner as in Example 1 except for the above.

Comparative Example 2 A non-expandable polystyrene particle having an average particle size of 0.7 mm was used in place of the non-expandable polystyrene particle in the backing coating composition of Example 1, and the other conditions were the same as in Example 1 except that the carpet for an automobile inner floor was used. Was manufactured.

Comparative Example 3 Non-expandable polystyrene particles having an average particle size of 0.03 mm were used in place of the non-expandable polystyrene particles in the backing coating composition of Example 1, and the other conditions were the same as in Example 1 except that the carpet for an automobile inner floor was used. Was manufactured.

Comparative Example 4 A carboxy-modified styrene-butadiene copolymer (manufactured by Nippon Synthetic Rubber Co., glass transition temperature 5 ° C.) and a polyethylene resin (trade name: Petrocene 202, manufactured by Tosoh Corporation) were used as backing coating agents. Then, a backing coating agent was used in which the latter was blended so as to be 200 parts by weight with respect to 100 parts by weight of the former, and the other steps were the same as in Example 1 to produce a carpet for an automobile inner floor.

Comparative Example 5 In place of the non-expandable polystyrene particles in the backing coating composition of Example 1, 300 parts by weight of expandable polystyrene particles having an average particle diameter of 0.2 mm (gas content: 5%) were used. Carpets for car interior floors were manufactured in the same manner as described above.

Comparative Example 6 In place of the non-expandable polystyrene particles in the backing coating composition of Example 1, 300 parts by weight of a vinyl chloride resin powder having an average particle size of 0.2 mm was used. Carpets were manufactured.

Example 2 Instead of the styrene-acrylonitrile-butyl acrylate-acrylic acid-acrylamide copolymer aqueous emulsion in the backing coating composition of Example 1, styrene (64% by weight) -2-ethylhexyl acrylate (30% by weight) Acrylic acid (2% by weight)-diacetone acrylamide (3% by weight)-acrylamide (1% by weight) copolymer (minimum film formation temperature 40 ° C) using a 50% by weight aqueous emulsion of solid content. In the same manner as in Example 1, a carpet for an automobile inner floor was manufactured.

Example 3 Instead of the styrene-acrylonitrile-butyl acrylate-acrylic acid-acrylamide copolymer aqueous emulsion in the backing coating composition of Example 1, styrene (35% by weight) -n-butyl acrylate (45% by weight) −α
-Methylstyrene (20% by weight) copolymer (minimum film forming temperature
A non-foamable polystyrene particle having a gas content of 1% and an average particle size of 0.2 mm is used in place of the polystyrene particle having an average particle size of 0.2 mm. Otherwise, a carpet for a car interior floor was manufactured in the same manner as in Example 1.

Comparative Example 7 Instead of the aqueous emulsion of styrene-acrylonitrile-butyl acrylate-acrylic acid-acrylamide copolymer in the backing coating composition of Example 1, n-butyl acrylate (35% by weight) -methyl methacrylate (63% by weight) %)-Acrylic acid (2% by weight) copolymer (minimum film-forming temperature of 40 ° C.) was used in the same manner as in Example 1 except that an aqueous emulsion having a solid content of 50% by weight was used.

Each of the carpets obtained in Examples 1 to 3 and Comparative Examples 1 to 7 was tested by the following test methods. The results were as shown in Table 1.

Three-point bending strength A test piece (150 mm long, 50 mm wide) is supported at a span of 100 mm, and a deformation load is applied vertically to the test piece at the center point of the sample at a rate of 50 mm / min using an Instron type testing machine. The maximum bending resistance value when loaded was measured.

Non-water permeable According to the water permeability test of JIS A-6910. The head was 250 mm, and the evaluation was made 12 hours later according to the following criteria.

×: Water permeated to the back surface and remained.

Δ: Water bleeding observed on the back side.

：: No water bleeding was observed on the back surface.

Heat resistance Carpet for interior car floor obtained by press molding at 85 ° C
The degree of deformation of the carpet when held for 48 hours was evaluated according to the following criteria.

×: Large deformation Δ: Slight deformation ○: No deformation Elasticity After winding the carpet with a winding diameter of 50 mmφ, the following criteria were evaluated according to each state when returning to the original shape after removing the load.

×: Breaks when wound.

Δ: Rollable without breaking, but poor return.

：: Roll without breaking and return to the original state.

 Mold fidelity The following criteria evaluated.

×: Large return after press molding △: Slight deformation ○: Good Examples 4-5 Comparative Examples 8-9 The same copolymer aqueous emulsion as in Example 1 and the same non-expandable polystyrene particles were used in Table 2
Various kinds of carpets for floors for automobiles were manufactured in the same manner as in Example 1 except for various changes as shown in FIG.

The physical properties of each of the obtained carpets are as shown in Table 2.

(C) Effects of the Invention According to the method of the present invention, a laminated molded article having a good balance in terms of three-point bending strength, water impermeability, heat resistance, elasticity, mold fidelity, shielding properties and shape retention properties. Can be easily manufactured without the need for complicated process control. Further, by selecting the glass transition temperature of the copolymer constituting the styrene-acrylic acid lower alkyl ester copolymer aqueous emulsion to be used, any of the resulting laminated excipients can be any of those having a high flexibility to those having a high rigidity. Properties can be given.

Claims (2)

(57) [Claims] 1. A styrene-based monomer (20 to 80% by weight) and another vinyl monomer (80 to 20% by weight) are emulsified on a fibrous base fabric (A) made of a material having a heat deformation temperature of 130 ° C. or higher. An aqueous emulsion of a styrene copolymer having a minimum film-forming temperature of 60 ° C. or lower obtained by polymerization is 100 parts by weight in terms of solid content, and the average particle size is 0.0
Non-expandable styrenic polymer particles of 5 to 0.5 mm in solid content
A backing coating agent blended in a proportion of 50 to 700 parts by weight is applied, and then heated and dried at a temperature lower than the thermal deformation temperature of the material of the fibrous base fabric (A) to form a resin coated base fabric. age,
Next, the obtained resin-coated base fabric is heated at a temperature equal to or higher than the softening temperature of the non-expandable styrene-based polymer particles and under conditions that the material of the fibrous base fabric (A) is not thermally deformed. Manufacturing method of shaped material. 2. The method according to claim 1, wherein the other vinyl monomer is a lower alkyl acrylate (alkyl group having 1 to 8 carbon atoms) or a lower alkyl methacrylate (alkyl group has 1 to 8 carbon atoms). Item 1. The production method according to Item 1.