JPS63205378A - Adhesive composition for carpet backing - Google Patents

Abstract

PURPOSE:To obtain the title composition which has excellent hot formability, shape retentivity, and fiber-fixing power, and is used in one-step fabrication, by mixing a styrene latex with a styrene/butadiene copolymer latex. CONSTITUTION:A styrene latex (A) is obtained by the copolymerization of 70-100wt.% aromatic vinyl monomer (a) and 30-0wt.% other copolymerizable monomer (b). A styrene/butadiene copolymer latex (B) is obtained by the copolymerization of 10-79wt.% component (a), 0-20wt.% component (b), 10-84wt.% aliphatic conjugated diene (c), 1-40wt.% alkyl ester of an ethylenically unsaturated carboxylic acid (d), and a vinyl cyanide monomer (e). On a dry weight basis, 30-90pts.wt. component A is then mixed with 70-10 pts.wt. component B to give an adhesive composition for carpet backing, which consists of 15-96wt.% component (a), 0.-20wt.% component (b), 2-70wt.% component (c), 0.2-30wt.% component (d), and 1-35wt.% component (e), has a mininum film-forming temperature of 60 deg.C or lower, and forms a continuous phase of the resin components when dried at 90 deg.C or higher.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an adhesive composition for backing carpets used as interior materials for automobiles.

[Conventional technology]

Needle-punched carpets and tufted carpets for automobile interiors are manufactured by coating or impregnating the back surface of the carpet with an adhesive composition mainly composed of styrene-butadiene co-monomer latex or ethylene-vinyl acetate resin emulsion. It is manufactured by a two-step processing method in which it is lined with a thermoplastic resin film such as polyethylene by heat fusion in order to impart thermoformability.

These carpets are cut, molded to match the shape of the car floor by press molding while heated, and then assembled into the car.

On the other hand, unlike the above-mentioned two-stage processing method, a so-called one-stage processing method is disclosed in JP-A-53-52776, in which a carpet that can be continuously molded is obtained by applying an aqueous plastic dispersion to the back surface of the carpet. ing.

[Problem that the invention seeks to solve]

In the conventional two-step processing method, the nonwoven fibers or pile yarns are fixed by full application or impregnation with an adhesive consisting of a styrene-butadiene copolymer latex or an aqueous emulsion of a resin, and then backed with a thermoplastic resin film. This gives the carpet thermoformability, but such a two-step processing method complicates the carpet manufacturing process, and therefore improvements have been desired.

On the other hand, the above-mentioned one-step processing method that imparts thermoformability to the adhesive without backing with a thermoplastic resin film has the ability to maintain thermoformability and its shape (called shape retention). ) is insufficient, and if attempts were made to improve the thermoformability and shape retention, there was a problem that the adhesion of the fibers would decrease and the fibers would unravel.

Therefore, it has been desired to develop a backing adhesive composition for one-stage processing that is excellent in all aspects of thermoformability, shape retention, and fiber adhesion.

[Means for solving problems]

In order to solve these problems, the present inventors conducted extensive research on adhesive compositions for carpet lining for one-stage processing, and found that
Rather than using a known aqueous plastic dispersion or a mixture of the dispersion as a backing adhesive as proposed in the above issue, a mixture of a styrenic latex and a styrene-butadiene co-N latex can be used to achieve a specific minimum film formation rate. A layered footwear layer in which the resin component forms a continuous phase when dried above a certain temperature - When a latex mixture is used as a backing adhesive, thermoformability, shape retention and fiber The present invention was completed based on the discovery that styrene latex (A) and styrene-butadiene copolymer latex CB) exhibit excellent effects in all aspects of adhesion. A mixture having a minimum film-forming temperature of 60°C or lower and adjusted so that the resin component becomes a continuous phase when dried at 90°C or higher is used as the main component. A carpet backing adhesive composition is provided.

By applying the adhesive composition of the present invention to needle-punched carpets or tufted carpets, it is possible to easily obtain automotive carpets having excellent thermoformability, shape retention, and fiber adhesion. can.

Further, unlike the above-mentioned two-stage processing method, the present invention does not require backing with a thermoplastic resin film, and is therefore excellent in terms of simplifying the carpet manufacturing process and improving productivity.

The present invention will be explained in more detail below.

0 Styrenic latex (A) Styrenic latex used in the present invention (8 is obtained by copolymerizing an aromatic vinyl monomer as a main component and other monomers that can be copolymerized with this) Aromatic vinyl monomers include styrene, α-methylstyrene, etc., and other copolymerizable monomers include 1,3-butadiene, acrylonitrile, methyl methacrylate, acrylic acid, fumaric acid, Examples include β-hydroxyethyl acrylate.

The styrenic latex (A) in the present invention preferably comprises 70 to 100M of an aromatic vinyl monomer and 0 to 30% by weight of other monomers copolymerizable therewith.

0 Styrene-butadiene copolymer latex (B) The styrene-butadiene copolymer latex (B) used in the present invention contains aromatic vinyl monomers, aliphatic conjugated diene monomers, and ethylene monomers. It can be obtained by copolymerizing all of the unsaturated carboxylic acid alkyl ester monomers and other monomers copolymerizable with them. Examples of aromatic vinyl monomers include styrene and α-methylstyrene, and examples of aliphatic conjugated diene monomers include 1,3-butadiene and 2-
Methyl-1,3-butadiene, etc., ethylenically unsaturated carboxylic acid alkyl ester monomers include methyl methacrylate, ethyl acrylate, etc., and other monomers that can be copolymerized with these include acrylonitrile, methacrylatetril, acrylic. acid, fumaric acid, methacrylic acid, itaconic acid, β-hydroxyethyl acrylate, and the like.

The styrene-butadiene copolymer latex CB) in the present invention includes 10 to 79 deuteranyl aromatic vinyl monomers, 1 to 40% by weight of aliphatic conjugated diene monomers, and ethylenically unsaturated alkyl carboxylates. It is preferable to inherit 1 to 40 I weight percent of ester monomers and 0 to 20 weight percent of other monomers copolymerizable with these, and 10 to 40 M weight percent of aliphatic conjugated diene monomers. is even better.

0 latex mixture The latex mixture used in the present invention has a solid content of styrene latex (30 to 90 parts) and styrene-butadiene (M), lx-form silatex (B) 1
0 to 70: preferably consists of a styrene latex (A) of 50 to 8 parts and a styrene-butadiene copolymer latex (B) of 20 to 50 parts.
More preferably, it consists of parts by weight.

The latex mixture in the present invention contains 15 to 96 fi amount% of aromatic vinyl monomers and 2% of aliphatic conjugated diene monomers.
~70% by weight, vinyl cyanide monomer 1~35 monomers, ethylenically unsaturated carboxylic acid alkyl ester monomer 0.2~3ON, and other monomers copolymerizable with these 0~ It is preferably 20% by weight, and more preferably 10 to 200 to 20 parts by weight of the aliphatic conjugated diene monomer. Furthermore, it is preferable to use the vinyl cyanide monomer only in either the styrene latex (A) or the styrene-butadiene copolymer latex CB).

The minimum film-forming temperature of the latex mixture of the present invention is 60°C or lower, but if it exceeds 60°C, the adhesion of the fibers will decrease, and if the latex mixture is dried at 90°C or higher, the resin component will form a continuous phase. However, if the resin component does not form a continuous phase, the shape retention property will be poor, which is not preferable.

Styrenic latex (A) of the present invention and styrene-
The butadiene copolymer latex (B) is produced by a known method. That is, a batch addition method, a divided addition method, a continuous addition method, a two-stage overlapping method, a power feed method, etc. can be applied.

The adhesive composition of the present invention can contain antioxidants, fillers, flame retardants, thickeners, surfactants, crosslinkers, and the like.

Carpets to which the adhesive composition of the present invention can be applied include polypropylene, polyester, nylon, acrylic,
These are needle punch carpets and tufted carpets that use fibers such as wool, and are applied to automobile carpets and interior materials that require a heat molding process.

EXAMPLES Below, the present invention will be specifically explained with reference to examples.
The present invention is not limited in any way by these Examples.

Note that all parts and % in the examples mean parts by weight and % by weight unless otherwise specified.

Example-1 (Preparation of copolymer latex and latex mixture) 1.0 parts of sodium dodecylbenzenesulfonate was added to 100 parts of water.
Add 5 parts and dissolve. The monomer mixture shown in Table 1 was added to this, and the mixture was further kept at 1-60°C for emulsion polymerization. Polymerization was stopped when the monomer polymerization conversion rate reached 97%.

Unreacted monomers in the obtained latex were removed under reduced pressure to obtain copolymer latex A-D'i. The obtained copolymer latexes were mixed in the layout shown in Table 2 to form a latex mixture (1).

(41 was obtained. These latex mixtures (++,
The minimum film forming temperature of <:+) was measured and the results are shown in Cloth-2.

The films obtained by drying these latex at 120°C were observed using a total electron microscope.

This confirmed that the resin component formed a continuous phase.

(Preparation of adhesive composition) For each of the obtained latex mixtures (i) and (ii), 1 part of antioxidant (Sumilyzer S; Sumitomo Chemical Co., Ltd.) was added to 100 parts of co-M combined latex (solid content).
), 0.3 part of thickener (Aron A7150; manufactured by Toa Kaisei Kagaku Kogyo ■), and 1 part of surfactant (Emar 2EN;
Kao Soap (manufactured by Kao Soap) is added to achieve a solid content of 47% and a viscosity of 20.
00 cps adhesive compositions (2) and (2) were prepared.

Margin Table 2 below (Test results) Each of the obtained adhesive compositions ■ and ■ was foamed to 3 times the volume using a Hobart mixer, and applied to the back side of a polypropylene needle punch carpet at a coating amount of 150 Pr/rn'. and impregnated the inside. After that, 130℃
For carpet samples obtained by drying for 5 minutes at
Moldability, shape retention, and fiber adhesion were tested based on the following measurement methods.

The results are shown in Table-3.

Aging moldability: Carvette sample '11 was heated in an oven at 30° C. for 5 minutes and pressed with a convex-concave mold to form a mold.

Measure this typed angle and Evaluation was made based on the criteria.

○: Over 80 degrees (good) △F 5 degrees to 80 degrees (inadequate) The mold was left to stand and the angle of the part was measured. This change in angle was evaluated based on the following criteria.

O: Less than 10 degrees (good) △: 10 to 15 degrees (inadequate) ×: More than 15 degrees (woodenness) Rub the back side of the fiber-fixed crab carpet sample with a metal piece to prevent the adhesive from falling off and the fibers from falling off. The degree of pilling was evaluated based on the following criteria.

○: No adhesive falling off, good pilling △: Some adhesive falling off, pilling slightly poor ×: A lot of adhesive falling off (powder falling), pilling poor Comparative example Monomer composition shown in Table-1 The same operations as in Examples were performed to obtain copolymer latexes E and F'i. Latex mixtures (11) to (V) were obtained by performing the same operation as in the example.

The minimum film forming temperature of the obtained latex mixture was measured and the results are shown in Table 2. When the latex mixture a+++~(Vl was observed with an electron microscope in the same manner as in the example, it was found that (11) and (Vl) have a resin component forming a continuous phase and 0φ
It was found that the resin component did not form a continuous phase.

[Effects of the present invention] The adhesive composition obtained by the present invention has excellent moldability, shape retention, and fiber properties necessary for automobile carpets. At the same time, the adhesive composition of the present invention can omit the two-step process of backing with a thermoplastic resin film, simplifying the carpet manufacturing process and increasing productivity. It also has the effect of improvement.

Claims (1)

[Claims] 1. A mixture of a styrene latex (A) and a styrene-butadiene copolymer latex (B), wherein the mixture has a minimum film forming temperature of 60°C or less, and 90°C An adhesive composition for carpet lining, characterized in that a mixture prepared by adjusting the resin component to form a continuous phase when dried is used as a main component. 2. The latex mixture contains 30 to 90 parts by weight of styrenic latex (A) and styrene based on dry weight parts.
2. The carpet lining adhesive composition according to claim 1, comprising 10 to 70 parts by weight of the butadiene copolymer latex (B). 3. The latex mixture contains aromatic vinyl monomers 15-9
6% by weight, 2 to 70% by weight of aliphatic conjugated diene monomer,
Consisting of 1 to 35% by weight of vinyl cyanide monomer, 0.2 to 30% by weight of ethylenically unsaturated carboxylic acid alkyl ester monomer, and 0 to 20% by weight of other monomers copolymerizable with these. , and contains a vinyl cyanide monomer only in either (A) or (B). .