JPH0114351B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a carpet with excellent cushioning, and particularly to a carpet that is useful as a floor covering material for automobiles. Traditionally, carpets have been made using rubber latexes such as styrene-butadiene rubber, butadiene-acrylonitrile rubber, vinyl chloride copolymers, styrene-acrylic acid alkyl esters, etc. to prevent the pile threads of the original rug from coming off and to stabilize the shape. Polymers, aqueous resin emulsions such as vinyl acetate/acrylic acid alkyl ester copolymers, vinylidene chloride copolymers, polyvinyl acetate, ethylene/vinyl acetate copolymers (hereinafter, latex and aqueous resin emulsions are referred to as "aqueous resin emulsions") (described as a representative example) has been marked down. As a method for further improving the cushioning properties of carpets backed with this aqueous resin emulsion, we previously proposed a carpet in which a foam sheet was adhered to the back side of this resin emulsion backing material (Utility Application No. 57-170656). , 57-195731
(see issue). However, this method requires a backing layer formation process and a foam sheet bonding process, and
In order to prevent the foam sheet from breaking due to bending, it is necessary to further laminate a non-foam sheet to the foam sheet. The present invention has been made for the purpose of performing the previously proposed manufacturing method for laying materials in fewer steps, and by using a resin aqueous emulsion containing expandable porostyrene resin particles as a backing material. This problem has been solved. That is, in the present invention, the particle size is
An aqueous resin emulsion containing expandable polystyrene particles of 1.5 mm or less is applied, and then the applied surface is heated to foam the expandable polystyrene particles, and the aqueous resin emulsion is dried to form polystyrene foam on the back side of the original rug. The present invention provides a method for manufacturing a laying material having cushioning properties, which is characterized by forming a backing layer in which body particles protrude. In the present invention, any material can be used as the raw material for the carpet, including natural fibers, chemical fibers,
Raw fabrics made from various fibers such as synthetic fibers can be used. In general, raw material for tufted carpet is prepared by erecting piles on a primary base fabric knitted from needle punch carpet or flat yarn obtained from fibers such as wool, nylon, polyacrylonitrile, polyacetate, polypropylene, etc.; A tufted carpet fabric is used, with a needle punch carpet as the primary base fabric and a pile erected thereon. Among these, inexpensive needle punch carpets are preferred for automobile interiors. Next, as a backing material, an aqueous resin emulsion that acts as a binder for pile threads and as an adhesive for polystyrene foam particles has a glass transition point of -65℃~
+150°C aqueous emulsion of resin, such as polyvinyl acetate, vinyl chloride/vinylidene chloride copolymer, styrene/butadiene copolymer rubber, styrene/methyl methacrylate copolymer, styrene/n-butyl acrylate copolymer, Latexes such as ethylene/vinyl acetate copolymer, styrene/n-butyl acrylate/acrylic acid copolymer, vinylidene chloride/acrylonitrile/acrylic acid copolymer, and aqueous emulsions may be used alone or in mixtures. In terms of moldability and flexibility of the laying material, aqueous resin emulsions and latexes with a glass transition point of 20°C or lower are preferred; conversely, to impart moldability to the laying material, aqueous resins with a glass transition point of 80°C or higher are preferred. Emulsions are preferred. Aqueous emulsions with a glass transition point of 80°C or higher include (a). Polyn-propyl methacrylate (Tg81℃), polystyrene (100℃), polyacrylonitrile (100℃), polymethyl methacrylate (105℃), polymethacrylic acid (130℃), polyitaconic acid (130℃), polyacrylamide (153℃)
In addition to aqueous emulsions of homopolymers such as (b). 50 to 100% by weight, preferably 65 to 95% by weight of vinyl monomer, which is the raw material for these polymers, and other vinyl monomers such as 2-ethylhexyl acrylate (Tg - 85°C), acrylic acid n. Butyl (-54℃),
Ethyl acrylate (-22℃), isopropyl acrylate (-5℃), 2-ethylhexyl methacrylate (-5℃), n-propyl acrylate (8℃)
), n-butyl methacrylate (20℃), vinyl acetate (30℃), ethyl methacrylate (65℃), vinyl chloride (79℃), etc. or vinylidene chloride (-18℃), etc.
°C) Aqueous emulsion of a copolymer with 50% by weight or less, preferably 35 to 5% by weight It is the glass transition point of coalescence], (c). Resin aqueous emulsion with Tg +80-155°C 50-97% by weight, preferably 55-95
% by weight and 50 to 3% by weight, preferably 45 to 5% by weight of an aqueous resin emulsion having a Tg of -85°C to less than +80°C. The resin solid content concentration of aqueous emulsion is usually 20~
60% by weight, and the diameter of the dispersed resin particles is
It is 10μ (microns) or less, preferably 0.05 to 1.0μ. Examples of aqueous resin emulsions having a glass transition point of 20°C or lower include (i) 2-ethylhexyl acrylate, n-butyl acrylate, ethyl acrylate, isopropyl acrylate, 2-ethylhexyl methacrylate, n-propyl acrylate; , n-butyl methacrylate, vinylidene chloride, ethylene, butadiene 20-100% by weight (ii) Vinyl acetate, ethyl methacrylate, vinyl chloride, n-propyl methacrylate, styrene, acrylonitrile, methacrylic acid Emulsion polymer containing 80% by weight or less of a monomer selected from methyl, acrylic acid, itaconic acid, acrylamide, and methacrylamide (iii) 0 to 5% by weight of a monomer selected from diacetone acrylamide, maleic anhydride, and diethylene glycol diacrylate can be given. Expandable polystyrene resin particles with a particle size of 1.5 mm or less, preferably 0.2 to 0.8 mm, are blended into this aqueous resin emulsion at a ratio of 10 to 100 parts by weight per 100 parts by weight of the resin in the emulsion. Used as a material. If the particle size exceeds 1.5 mm, the workability of mixing with the emulsion will be poor, and the expandable polystyrene particles will move to the upper part of the emulsion and will be easily separated. In other words, the workability and storage stability of the bucking material are poor. Furthermore, if the particles are large, the coating properties of the backing material will be reduced, and furthermore, after the backing material is applied to the original rug, the expandable polystyrene particles tend to fall off from the original fabric. Such expandable polystyrene particles are produced by emulsifying styrene containing a polymerization initiator and, if necessary, a vinyl monomer such as methyl methacrylate, vinylbenzene, or acrylic acid in water, and heating the mixture to polymerize the vinyl monomer such as styrene. Then, an expanding agent such as butane or heptane is injected into the suspension in which the polymer particles are dispersed, and the volatile expanding agent is impregnated into the polymer particles at a ratio of 3 to 7% by weight. can get. Moreover, when carrying out suspension polymerization of a vinyl monomer such as styrene, it can also be obtained by carrying out the polymerization while supplying the above-mentioned swelling agent to the suspension. This bucking material contains calcium carbonate, aluminum hydroxide, clay, talc, barium sulfate,
Extender pigments such as perlite, pigments and dyes such as red iron, malachite green, and titanium oxide can also be blended. The viscosity of bucking material at 20℃ is 500 to 8000
Centipoise is preferred from the viewpoint of application. The bucking material is applied to the original rug using a spray, brush, foam coater, roll, etc.
Generally, this is done using a roll coater. The amount of bucking material applied is 60 to 1000 g/m ² (solid content),
Preferably it is 80-300g/ ^m2 . Generally, the total weight of the backing material is 30 to 100% by weight (solid weight) of the weight of the original rug. Heat drying of the applied emulsion and foaming of the expandable resin particles can be carried out by any method. For example, heating cylinders, infrared heating machines,
Although a hot air dryer, a suction dryer, etc. can be used, it is preferable to use a hot air dryer. Further, drying can be carried out at 80 to 180°C, but it is preferably carried out with hot air at 100 to 140°C in order to prevent fiber deterioration and to ensure sufficient foaming. This heating causes the expandable polystyrene particles to
It expands by ~50 times and becomes a foam 1 with a particle size of 0.5 to 4.5 mm, which is adhered to the rug material 3 by a membrane 2 formed by the resin emulsion and protrudes from the surface of the membrane 2 (see Figure 1). . Therefore, the laying material 4 of the present invention is a laying material with significantly improved cushioning properties due to the presence of such foam particles 1. In addition, as a resin emulsion, the glass transition point is
When using resin emulsion at 80℃ or higher,
Since the laying material has moldability, the laying material can be shaped into a desired shape by heating to a temperature at which the membrane 2 of the backing layer melts and press-molding the laying material. Hereinafter, the present invention will be explained in more detail with reference to Examples. Manufacturing example of needle punch carpet A fiber mat (400 g/m ² ) randomly stacked with 15 denier polypropylene (melting point 164°C) fibers with a fiber length of approximately 100 mm is punched using a 15-18-32-3RB needle. Needling was performed at a rate of 50 needles per square inch to obtain a needle punch carpet with a thickness of approximately 3 mm. This needle-punched carpet was used as the raw material for the rug used in the Examples and Comparative Examples below. Example 1 On the back side of a needle punch carpet, as backing materials, ``styrene (49% by weight), n-butyl acrylate (49% by weight), and acrylic acid (2% by weight) were applied.
Aqueous emulsion of copolymer (resin particle size 0.1~
0.2 micron, solid content 50% by weight, film forming temperature 20℃)
To 100 parts by weight, 10 parts by weight of expandable polystyrene particles (containing 5.5% butane) with an average particle size of 0.33 mm are blended, and a thickener "Latecol D" (trade name) manufactured by Yuka Verdice Co., Ltd. is blended. The viscosity at 25℃ was adjusted to 3,000 cps, and the emulsion was coated with a licker roller to a concentration of 150 g/m ² (solid content).Then, the emulsion was applied to a needle punch carpet using a nip roll. Impregnated.
Then, the needle punch carpet impregnated with the emulsion is heated with hot air at 130°C for 10 minutes to remove moisture and expand the expandable polystyrene particles, which have a bulk density of about 0.15 g/cm ³ and a particle size of 0.5 to 0.5 g/cm 3 .
A laying material was obtained in which 1.5 mm polystyrene foam particles were adhered to the back side of a needle punch carpet via a resin film. The cushioning properties of this product were evaluated using the following method and were found to be good. Evaluation method: The initial wall thickness when a load of 50 g/cm ² is applied to the laying material is t ₀ , then the wall thickness when a load of 400 g/cm ² is applied for 1 minute is t ₁ , and this load is removed. , when the wall thickness after 1 minute is t ₂ , compression ratio = t ₀ - _{t 1} / t ₀ × 100 compression modulus = t ₂ - t ₁ / t ₀ - _{t 1} × 100 deformation ratio = ( It was calculated as 1-t ₂ /t ₀ )×100, and those with a small deformation rate and a small thickness change rate were considered to have good cushioning properties. Examples 2 to 3, Comparative Example 1 A laying material was obtained in the same manner as in Example 1, except that the blending ratio of the aqueous resin emulsion and expandable polystyrene particles in the backing material was changed as shown in Table 1. did. The performance of the laying materials is shown in the same table. For reference, the cushioning properties of needle felt "Ango Felt" manufactured by Company A, 650 g/m ^2, are shown in the same table.

[Table] Example 4 In Example 1, an aqueous emulsion of styrene (80% by weight)/n-butyl acrylate (20% by weight) copolymer was used as the backing material (resin particle size approx.
A laying material with excellent cushioning properties was obtained in the same manner except that 100 parts by weight of foamable polystyrene particles (100 parts by weight of 0.2 micron, solid content 50%) was used. In addition, this laying material was heated to 120°C to soften the resin film of the backing layer, and then molded using a cooling press mold by applying a pressure of 5 kg/cm ² for 5 minutes.
Manufactured carpet for automobile interior floors.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a laying material obtained by implementing the present invention. In the figure, 1 is a polystyrene foam particle, 2 is a resin film, 3 is a rug material, and 4 is a laying material.

Claims (1)

[Claims] 1. An aqueous resin emulsion containing expandable polystyrene particles with a particle size of 1.5 mm or less is applied to the back side of the original rug, and then the applied surface is heated to cause the expanded polystyrene particles to expand. 1. A method for producing a laying material having cushioning properties, which comprises drying the aqueous resin emulsion to form a backing layer in which polystyrene foam particles protrude on the back side of an original rug. 2 The ratio of expandable polystyrene particles to 100 parts by weight of resin in the resin aqueous emulsion is 10 to 10%.
100 parts by weight of the method for producing a laying material according to claim 1.