JPH0756016B2 - Adhesive composition having thermoformability - Google Patents

Description

TECHNICAL FIELD The present invention relates to an adhesive composition that imparts thermoformability to a fiber base material or paper by coating or impregnating the fiber base material or paper.

[Conventional technology]

In order to impart thermoformability to a fiber base material, for example, needle punched carpets and tufted carpets for automobile interiors have an adhesive containing styrene-butadiene copolymer latex or ethylene-vinyl acetate resin emulsion as a main component. A two-step processing method has been performed in which after applying or impregnating the agent composition on the back surface of the carpet, a thermoplastic resin film such as polyethylene is lined by heat fusion.

Further, Japanese Patent Application Laid-Open No. 53-52776 discloses a so-called one-step processing method in which a continuously moldable carpet is obtained by applying an aqueous plastic dispersion liquid to the back surface of the carpet.

[Problems to be Solved by the Present Invention]

In the conventional two-step processing method, the non-woven fabric fiber or pile yarn is fixed by applying or impregnating an adhesive consisting of an aqueous emulsion of styrene-butadiene copolymer latex or resin, and further lining the thermoplastic resin film. This gives the carpet thermoformability, but such a two-step processing method complicates the carpet manufacturing process, and therefore improvement thereof has been desired.

On the other hand, in the one-step processing method that imparts thermoformability to the adhesive without backing the thermoplastic resin film, the hard texture (rigidity) required for the product is insufficient, and it is attempted to improve the rigidity. If so, there is a problem that the fixing force of the fiber is reduced.

Therefore, it has been desired to develop an adhesive composition having excellent thermoformability for one-step processing, which is excellent in terms of rigidity and fiber adhesion.

[Means for solving problems]

The present inventors, as a result of intensive studies on an adhesive composition having thermoformability in order to solve such problems,
A synthetic resin emulsion (A) having a specific glass transition point and a synthetic rubber latex (B) having a specific glass transition point are mixed in a specific ratio, and a crosslinking agent and / or a vulcanizing agent are added to the mixture. We have found the fact that by using a compound obtained by compounding in a specific ratio as an adhesive, an excellent effect is exhibited in terms of rigidity and fiber adhesion, and the present invention has been completed.

That is, the present invention, in terms of solid content weight, is a copolymerizable aromatic vinyl-based monomer and acrylic acid, methacrylic acid, itaconic acid, fumaric acid, β-hydroxyethyl acrylate, acrylonitrile, acrylamide copolymerizable. Synthetic resin emulsion (A) having a glass transition point of 80 to 120 ° C., which is obtained by copolymerizing other monomer
Based on 100 parts by weight of a mixture of 50% by weight and 70 to 50% by weight of a styrene-butadiene synthetic rubber latex (B) having a glass transition point of 0 to 50 ° C., a crosslinking agent and / or
Alternatively, the present invention provides an adhesive composition having thermoformability, which comprises 0.1 to 25 parts by weight of a vulcanizing agent (C).

By applying or impregnating a fiber base material or paper with the adhesive composition of the present invention, a fiber base material or impregnated paper having excellent rigidity and excellent fiber fixing force can be easily obtained.

Further, unlike the above-described two-step processing method, the present invention does not require lining of the thermoplastic resin film, and is therefore excellent in terms of simplification of the carpet manufacturing process and improvement of productivity.

Hereinafter, the present invention will be described in more detail.

Synthetic Resin Emulsion (A) The synthetic resin emulsion (A) used in the present invention is
It can be obtained by copolymerizing an aromatic vinyl monomer and another monomer copolymerizable therewith. Examples of the aromatic vinyl-based monomer include styrene and α-methylstyrene. Other copolymerizable monomers include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, β-hydroxyethyl acrylate, acrylonitrile, acrylamide and the like.

The glass transition point of (A) is in the range of 80 to 120 ° C, and when the glass transition point is less than 80 ° C, the rigidity is lowered. On the other hand, if the temperature exceeds 120 ° C, the fixing strength of the fibers will be reduced.

Synthetic Rubber Latex (B) The styrene-butadiene synthetic rubber latex (B) used in the present invention is obtained by copolymerizing styrene and butadiene, and is an unsaturated carboxylic acid copolymerizable with these monomers, Further, those obtained by copolymerizing acrylonitrile and the like are preferable.

The glass transition point of (B) is in the range of 0 to 50 ° C, and when the glass transition point is lower than 0 ° C, the rigidity decreases, and further 50 ° C.
If it exceeds, the fixing strength of the fibers will decrease.

Latex mixture In the latex mixture used in the present invention, the mixing ratio of the synthetic resin emulsion (A) and the synthetic rubber latex (B) is in the range of (A) / (B) = 30-50 / 70-50. Is.

If the usage ratio of (A) is less than 30% by weight, the rigidity will decrease, and
If the content is more than weight%, the fiber's fixing strength is lowered, which is not preferable.

Crosslinking Agent or Vulcanizing Agent (C) Examples of the crosslinking agent or vulcanizing agent used in the present invention include zinc white, compounds having an epoxy group, blocked isocyanate compounds, ethyleneurea compounds, melamine resins, urea resins, sulfur and peroxides. Examples thereof include oxides, and these can be used alone or in combination of two or more.

The crosslinking agent or vulcanizing agent (C) is used in an amount of 0.1 to 25 parts by weight based on 100 parts by weight (solid content) of the latex mixture.

If the cross-linking agent or the vulcanizing agent is less than 0.1 parts by weight, the rigidity will decrease, and if it exceeds 25 parts by weight, the rigidity will not be improved, which is not economically preferable.

The adhesive composition of the present invention may contain an antioxidant, a filler, a film forming aid, a flame retardant, a thickener, a surfactant and the like.

The adhesive composition of the present invention is applied to a fiber base material or impregnated paper such as tufted carpet, needle punched carpet and nonwoven fabric using fibers such as polypropylene, polyester, nylon, acrylic and wool.

When applying or impregnating the adhesive composition of the present invention, the adhesive may be foamed or thickened to be used, and as a processing method thereof, a lick roll, a squeezing roll, a spray gun,
Examples include stealing. Further, in order to completely impregnate the fiber base material or the paper, it is preferable to squeeze the coated or impregnated adhesive composition with a squeezing roll. After applying or impregnating the adhesive composition, the moisture can be removed by heating to obtain a moldable product. Examples of the method for molding the product include a molding method using a pressure roll or a press molding machine after heating.

It should be noted that the application of the adhesive composition of the present invention to the back surface of the carpet does not hinder the backing of the thermoplastic resin film such as polyethylene by heat fusion.

〔Example〕

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

All parts and% in the examples mean parts by weight and% by weight, unless otherwise specified.

Examples 1 to 3 and Comparative Examples 1 to 3 synthetic resin emulsion (A) having a glass transition temperature of 110 ° C.
(Styrene / acrylonitrile / acrylic acid = 77/20 /
3) and synthetic rubber latex with a glass transition temperature of 10 ° C (B)
(Styrene / butadiene / acrylonitrile / acrylic acid = 51/37/10/2) were mixed at a ratio shown in Table 1 to obtain a latex mixture.

An ethylene urea compound as a cross-linking agent (C) was added at a ratio shown in Table 1 to 100 parts (solid content) of each of the obtained latex mixtures, and further 1 part of an antioxidant (Sumilyzer).
S: Sumitomo Chemical Co., Ltd.) and 1 part of a surfactant (Emar 2FN: Kao Co., Ltd.) were added to obtain an adhesive composition.

Each of the obtained adhesive compositions was foamed in a volume of 3 times with a Hobart mixer, coated on the back surface of a polypropylene / polyester needle-punched carpet with a coating amount of 300 g / m ² , and the interior was impregnated. Then, the carpet sample obtained by drying at 130 ° C for 5 minutes was heated at 180 ° C for 5 minutes.
After heating for a minute, press molding was performed to obtain a test piece. The test pieces thus obtained were tested for rigidity and fiber fixing force based on the following measuring methods.

The results are shown in Table-1.

Rigidity: Cut a test piece into 50 mm width and use a 3-point bending jig
Bending was performed at a speed of 50 mm / min, the maximum load (kg) at that time was measured, and evaluation was performed according to the following criteria.

○: more than 3 kg △: 2-3 kg ×: less than 2 kg Fiber fixing force: Rub on the metal piece on the back surface of the carpet sample, and the degree of peeling of the adhesive and pilling of the fiber was evaluated based on the following criteria.

◯: Adhesive did not fall off and pilling was good. Δ: Adhesive fell off a little and pilling was a little poor. X: Adhesive fell off (powder drop) was large and pilling was bad. [Effect of the present invention] The adhesive composition obtained in the present invention can exhibit excellent rigidity and fiber fixing strength at the same time, and the adhesive composition of the present invention is called a lining of a thermoplastic resin film. The step of the two-step processing technique can be omitted, and the carpet manufacturing process can be simplified and the productivity can be improved.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location D06M 17/00 D21H 19/56

Claims (1)

[Claims] 1. A copolymerizable compound selected from aromatic vinyl monomers and acrylic acid, methacrylic acid, itaconic acid, fumaric acid, β-hydroxyethyl acrylate, acrylonitrile, and acrylamide in terms of solid content weight. 30 to 50% by weight of a synthetic resin emulsion (A) having a glass transition point of 80 to 120 ° C., obtained by copolymerizing the monomer of
And 100 parts by weight of a mixture of 70 to 50% by weight of a styrene-butadiene synthetic rubber latex (B) having a glass transition point of 0 to 50 ° C., a crosslinking agent and / or a vulcanizing agent (C) of 0.1 to 25 An adhesive composition having thermoformability, which is characterized by containing parts by weight.