JPH05287251A - Water-dispersed adhesive for flocking - Google Patents

Abstract

PURPOSE:To obtain the subject adhesive with which a polyolefin molding as a base can be directly flocked without priming. CONSTITUTION:This adhesive for flocking a polyolefin molding comprises a (meth)acrylic modified chlorinated polyolefin emulsion obtained by polymerizing a solution comprising a chlorinated polyolefin (of a chlorine content of 5-70wt.%), a mixture of at least one (meth)acrylic monomer in which the above polyolefin is soluble and a (meth)acrylic oligomer in the presence of a catalyst and an emulsion stabilizer in an aqueous medium. Because it is a water-based one, it can be safely used as an adhesive for flocking a polyolefin molding, can be applied thinly because of its high adhesive strength, and can give a bonded surface of good smoothness and a flocked molding of excellent appearance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-dispersion type flocking adhesive for a polyolefin molded article, which is prepared by directly applying the adhesive to a polyolefin molded article without containing toluene or xylene which is harmful to the human body. The present invention relates to a water-dispersion type flocking adhesive that adheres well to a polyolefin molded article when flocking and completely fixes a flocked pile.

[0002]

2. Description of the Related Art The interior of automobiles has become more and more luxurious year by year, and short fibers are used for ABS molded articles by using acrylic emulsion adhesive. Recently, in order to reduce the weight of the car body and reduce the cost, the polyolefin molded products have been used instead of the ABS molded products, but the acrylic emulsion adhesives do not adhere to the polyolefin molded products unlike the ABS molded products. It was necessary to apply a primer to a polyolefin molded product in advance and then bond an acrylic emulsion. Like this
Compared with the flocking of BS molded products, the flocking of polyolefin molded products requires a step of primer treatment, and therefore costs more. Therefore, there has been a strong demand from the industry for an adhesive capable of implanting hair in the same manner as an ABS molded product without a primer treatment. Publications relating to adhesives capable of flocking hair on conventional polyolefin molded articles, particularly polypropylene molded articles without the need for primer treatment, include binder compositions for flocking polyolefin molded articles (JP-A-1-107869) and water-based adhesives. There is JP-A-1-153777 for the agent composition, and JP-A-1-174579 for the water dispersion type adhesive.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The adhesives of the inventions of JP-A No. 1-153777 and JP-A No. 1-153777 contain harmful toluene and xylene in an amount of 15 to 24% by weight based on the total weight, and are harmful to the human body, and also a problem from the viewpoint of global environment conservation There is. Further, the invention of JP-A-1-174579 is an adhesive containing no toluene or other organic solvent,
In the emulsification step, toluene and isopropyl alcohol are concentrated and distilled off, and a large amount of water is distilled off to increase the resin concentration to a required level, which causes a problem that the sled is extremely expensive. The present invention is a primer for a polyolefin molded product.
It is an object of the present invention to provide a water-dispersed adhesive for flocking, which enables flocking as it is without using.

[0004]

It is known that chlorinated polyolefin is dissolved in an aromatic solvent such as toluene and adheres well to a molded polyolefin product, particularly a polypropylene molded product. From the aspect of adhesiveness to polyolefin only, chlorinated polyolefin alone is a good water-dispersible adhesive, but from the aspect of sprayability, adhesiveness of flocked pile and abrasion, it is actually Acrylic emulsion is mixed and used. However, even the relatively latest existing technologies have various drawbacks as described above.

In view of the above, the inventors of the present invention have made extensive studies to solve the above problems and achieve the object of the present invention, and as a result, completed the present invention. That is, the present invention is a type of (meth) acrylic monomer (B) capable of dissolving chlorinated polyolefins (A) and (A) chlorinated in a chlorine content range of 5 to 70% by weight, or (Meth) acrylic modification obtained by polymerizing a solution consisting of a mixture of two or more kinds and (meth) acrylic oligomers (C) in an aqueous medium in the presence of a catalyst and an emulsion stabilizer. The present invention relates to an adhesive for water-dispersed flocking of a polyolefin molded article, which is characterized by comprising a chlorinated polyolefin emulsion.

Chlorinated polyolefins, which act as adhesives to molded polyolefins, are generally significantly less polar than the polarity of the (meth) acrylic polymers, so that the (meth) acrylic produced by aqueous suspension polymerization. Polymer
Because it repels each other, it is difficult to obtain a uniform and safe emulsion. However, if both repulsive components are compatibilized and then emulsion polymerization is performed, the polymerized droplets can be smoothly polymerized without sticking to each other during the entire polymerization.

As a method for compatibilizing, there are methods such as graft polymerization to stabilize the non-compatible components, and addition of a compatibilizing agent to stabilize the system. Compatibilization was achieved by using a method that was simultaneously realized. That is, it is easily compatible with both (meth) acrylic polymer and chlorinated polyolefin (meth).
By selecting an acrylic oligomer (C) and copolymerizing it with a chlorinated polyolefin (A) and a (meth) acrylic monomer (B), the side chain part of the graft polymer is (Meth) acrylic oligomer (C)
Is introduced, and this portion improves the compatibility with chlorinated polyolefin.

The chlorinated content of the chlorinated polyolefins (A) used in the present invention is 5 to 70% by weight, preferably 20 to 40% by weight. If the chlorine content is less than 5% by weight, the compatibility with (meth) acrylic monomers in the low temperature range will be poor, and if the chlorination content exceeds 70% by weight, the adhesion with polyolefins will be reduced. .. As a raw material for chlorinated polyolefin, crystalline polypropylene, amorphous polypropylene, polybutene, low density polyethylene, high density polyethylene, ethylene-propylene copolymer, propylene-1-butene copolymer, ethylene-propylene-diene copolymer , Ethylene-vinyl acetate copolymer and the like. Further, a modified polyolefin resin in which a carboxyl group, a hydroxyl group, an acid anhydride group or the like is introduced into these is also used.

The chlorination of polyolefin is easy by the usual reaction method. For example, polypropylene is dissolved in carbon tetrachloride or chlorohydrocarbon such as chloroform, and a chlorine gas is added in the temperature range of room temperature to 130 ° C., with or without addition of a catalyst or under irradiation of ultraviolet rays, under pressure or normal pressure. It is done by introducing.

Further, the chlorinated polyolefins (A) include
Modified chlorinated polyolefins modified by modifying chlorinated polyolefins with maleic anhydride are also included. This modification is carried out by a known method. For example, chlorinated polyolefins are subjected to solvent substitution to form a toluene solution, maleic anhydride is introduced at a temperature range of 70 to 120 ° C, in the presence or absence of a catalyst, and in the presence of a third component, or in the presence of a catalyst. It is possible to react in the coexistence. By carrying out the present invention using the maleic anhydride-modified chlorinated polyolefins, a more stable adhesive can be obtained.

As the (meth) acrylic monomers (B) used in the present invention, those which easily dissolve the chlorinated polyolefins (A) and the (meth) acrylic oligomers (C) are preferred. To be selected. For example, methyl (meth) acrylate, ethyl (meth) acrylate,
Monofunctional (meth) acrylates such as isobutyl (meth) acrylate, normal butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate -Monomers containing carboxyl groups or acid anhydride groups such as acrylic acid, methacrylic acid, dimethylaminoethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) Acrylate,
Monofunctional (meth) acrylates having a functional group such as acrylamide are the main constituents, and examples of comonomers include styrenes such as styrene, chloromethylstyrene, paramethylstyrene, α-methylstyrene, and maleic anhydride. Acids, acid anhydrides such as itaconic anhydride, Veova
One or more monomers selected from vinyl esters of versatic acid such as 10, Veova 9 (trade name of Ciel Chemical Co., Ltd.) and vinyl esters such as vinyl acetate.
Are used alone or in combination.

Further, the (meth) acrylic oligomers (C) used in the present invention have a typical repeating unit in the molecule as a typical feature, and have at least one double bond in the molecule. Or, it has two or more. Further, of course, what is called a macromer or a macromonomer is included in this, but a normal macromer or a macromonomer (hereinafter referred to as a macromonomer, etc.) is a compound having a double bond at the end of the molecule. As is expected, those having a functional group such as a hydroxyl group or a carboxyl group at both ends of the molecule are also included.
These macromonomers and the like have a molecular weight in the range of several hundreds to 10,000, and the performance of the copolymer obtained as an adhesive varies depending on the type of macromonomer used and the molecular weight. Examples of the (meth) acrylic oligomers (C) include, in addition to macromonomers, caprolactone-modified (meth) acrylate oligomers, terminal hydroxyl group-containing (meth) acrylate oligomers, and oligoester (meth) acrylates. -, Urethane (meth) acrylate, epoxy (meth) acrylate and the like. Among these, those containing a functional group such as a hydroxyl group, a carboxyl group, an acid anhydride group or an amino group are also included.

The chlorinated polyolefins (A) of the present invention,
The copolymerization of the (meth) acrylic monomer (B) and the (meth) acrylic oligomer (C) is carried out by suspension polymerization or emulsion polymerization. At that time, as the dispersant used, gelatin, tragacanth gum, starch, methyl fiber,
Natural polymers such as carboxymethyl cellulose, hydroxypropyl cellulose and hydroxyethyl cellulose or derivatives thereof and polyvinyl alcohol, partially saponified polyvinyl alcohol, vinyl alcohol copolymers , Water-soluble organic polymer compounds such as polyacrylic acid salts, and sparingly water-soluble finely divided inorganic compounds such as barium sulfate, calcium sulfate, barium carbonate, calcium carbonate, magnesium carbonate and calcium phosphate, or mixtures thereof and talc, bentonite Inorganic polymers such as silicic acid, diatomaceous earth, and clay, and metal oxide powders are used. These dispersants have a large dispersing effect when used alone or in combination of two or more. While the dispersant has the effect of preventing coalescence of droplets (oil droplets), the emulsifier has a large ability to reduce surface tension and has a strong penetrating power, so droplets (oil droplets) can be made smaller. It has a function to make it.

As the emulsifier used, a surfactant is used. For example, an aromatic type polyoxyethylene alkyl ether such as polyoxyethylene alkyl ether, polyoxyethylene alkyl ether, etc.
Nonionic surfactants represented by higher alcohols such as ter and fatty acid derivatives such as polyoxyethylene fatty acid esters, sulfuric acid ester salts of polyoxyethylene alkyl (or alkylphenyl) ethers, and dialkyl sulfo amber. Acid ester sodium salt, higher alcohol sulfate ester soda, alkyl sulfonate, alkylbenzene sulfonate, alkyl naphthalene sulfonate, special polyacrylate, gluconate, carboxymethyl cellulose sodium salt, metal soap Such as sulfonic acid or carboxylic acid type anionic surfactants, cationic ammonium surfactants such as alkylammonium chloride, trimethylalkylammonium bromide and alkylpyridinium chloride, alkylglycine, dimethylalkylpentaine, etc. Surfactants.

The amount of the emulsifier added is 0.1 to 50 parts by weight, preferably 0.2 to 45 parts by weight, based on 100 parts by weight of the resin solid content. As the polymerization method, a solution and a dispersant consisting of dissolved chlorinated polyolefins (A), (meth) acrylic monomers (B) and (meth) acrylic oligomers (C) before the initiation of polymerization Further, emulsion (hereinafter referred to as pre-emulsion) homogenized with an aqueous solution in which an emulsifier is dissolved is dropped into a reaction can containing deionized water in advance and agitated and polymerized in a nitrogen atmosphere.

[0016]

[Action]

[How to Use the Adhesive of the Present Invention] The water-dispersible adhesive for flocking of the present invention is used as follows. After degreasing the surface of the polyolefin molded product with isopropyl alcohol, apply an adhesive of about 20 poise to 100-200 μm with an air spray.
To the thickness of 40 to 50KV on nylon pile
The pile can be applied to the adhesive by applying a voltage of. Drying is performed at a temperature of 60 to 80 ° C for 30 minutes to complete the hair transplant. Nylon is often used as a pile type in terms of vivid color and abrasion resistance, but it is not particularly limited, and may be piles such as polyester, acrylic, modacrylic and rayon. In the examples of the present invention, a flocking test was substituted for the test of adhering a cotton cloth to measure the adhesive force. Polyolefin molded products to be flocked are molded products of polyolefin such as polyethylene, polypropylene and ethylene propylene terpolymer, blended with fillers such as glass fiber, calcium carbonate and talc, or polycarbonate. Polyolefin molded products modified with polymers such as polystyrene, acrylonitrile-styrene copolymer, polymethylmethacrylate, polyphenylene oxide, nylon, polyester, ABS, and rubber may be used. When the adhesive agent for flocking of the present invention is used, it has a strong adhesive force and can therefore be applied thinly, the surface of the adhesive agent is smooth, and the appearance after flocking is remarkably excellent.

[0017]

【Example】

[Example 1] 2-ethylhexyl methacrylate 42.7
g, Macromonomer-AW6SEH (manufactured by Toa Gosei Chemical Industry Co., Ltd .: 50%, 2-ethylhexyl methacrylate solution) 26.2 g, chlorinated polypropylene (manufactured by Toyo Kasei Co., Ltd .: Hadren 14-LWP: chlorine content rate) 27%) 24.0
Add g and 200 ml to a 200 ml four-necked flask equipped with a stirrer.
After melting until uniform at ℃, cooled to 50 ℃, methacrylic acid 2.0g, polymerization catalyst (Nippon Yushi Co.
BO: benzoylperoxide paste) (1.4 g),
A homogeneous solution (D) was obtained. On the other hand, in 91.1 g of deionized water, 4.4 g of polyvinyl alcohol (Kuraray Co., Ltd .: Kuraray Poval), 0.6 g of hydroxypropyl cellulose (Nippon Soda Co., Ltd .: HPC-SL), 0.6 g of Neocol P ( Daiichi Kogyo Seiyaku Co., Ltd .: anionic surfactant) 1.2 g, Neugen EA-190 D (Daiichi Kogyo Seiyaku Co., Ltd .: nonionic surfactant) 2.7 g were added to form a uniform and transparent aqueous solution (E). Obtained. Solution (D) in a 500 ml stainless steel container
And (E) were added, and the mixture was stirred at 20,000 rpm for 5 minutes using an emulsifying machine to prepare a pre-emulsion. 35 g of deionized water was placed in a 500 ml four-necked flask equipped with a stirrer, a dropping funnel, a thermometer, and a nitrogen inlet, and after the air in the flask was sufficiently replaced with nitrogen, the water temperature in the flask was adjusted to 63 with an oil bath.
The temperature is raised to ℃, the pre-emulsion in the dropping funnel is added dropwise over 3 hours with stirring, and the reaction is continued for another 3 hours at 63 ℃.
Aged to complete the reaction. The emulsion obtained had a nonvolatile content of 38.8% by weight, and had a viscosity of 5.5 poise (B type viscometer, rotor No. 2, 30 rpm) at 25 ° C. Thickener (Kanebo NSC Co., Ltd .: Yodozol KA)
-109) to adjust the viscosity to 20 poise (B type viscometer, rotor no.
(4, 60 rpm) to increase the viscosity, and apply it to the injection square plate of polypropylene for water-dispersion flocking that does not contain organic solvents such as toluene.
Coater (No160, manufactured by Eto Kikai Shokai, coating thickness: 240 μm)
Apply an adhesive using a cotton cloth (Kanakin No. 3, JIS
After confirming that the entire surface was wet, it was placed in a constant temperature dryer and dried at 80 ° C. for 30 minutes. Two hours after being taken out from the dryer, a 180 degree peel test was conducted using a tensile tester at a pulling speed of 50 mm / min. As a result, a peel strength of 4.4 kg / 4 cm was exhibited.

[Example 2] The same procedure as in Example 1 was repeated except that a chlorinated polypropylene modified with maleic anhydride (hardren 14-ML) was used in place of the chlorinated polypropylene (hardren 14-LWP). It was carried out. The emulsion obtained has a nonvolatile content of 38.6% by weight and a viscosity of 6.0 poise at 25 ° C. (B type viscometer, rotor No. 2, 30 rp).
m) The viscosity is increased to 20 poise (B-type viscometer, rotor No4, 60 rpm) with a thickener (Kanebo NSC Co., Ltd .: Yodozol KA-10) and does not contain organic solvent such as toluene. A water dispersion type flocking adhesive was used. The peel strength measured by the tensile tester was 4.2 Kg / 4 cm.

Example 3 Example 3 was repeated except that a chlorinated propylene-1-butene copolymer was used instead of the chlorinated polypropylene (hardren 14-LWP). The emulsion obtained has a nonvolatile content.
It was 38.5% by weight and the viscosity was 15 poise (B-type viscometer, rotor No. 4, 60 rpm) at 25 ° C. The viscosity is increased to 20 poise (B-type viscometer, rotor No4, 60 rpm) with a thickener (Kanebo NSC Co., Ltd .: Yodozol KA-10) and does not contain organic solvent such as toluene. A water dispersion type flocking adhesive was used. Peel strength by tensile tester is 4.3Kg / 4cm
It was.

Example 4 The procedure of Example 1 was repeated except that only methacrylic acid was used. The obtained nonvolatile content was 38.2% by weight, and the viscosity was 5.8 poise (B
Type viscometer, rotor No. 2, 30 rpm). Thickener (Kanebo NSC Co., Ltd .: Yodozol KA-1)
0) to 20 poise (B type viscometer, rotor No. 4, 60r
pm) to obtain an aqueous dispersion type flocking adhesive containing no organic solvent such as toluene. Peel strength by tensile tester is 6.
It was 1kg / 4cm.

[0020]

[Table 1]

The effects of the present invention are summarized as follows. After the chlorinated polyolefins (A) and the oligomers (C) are dissolved in the (meth) acrylic monomer (B), the solution is polymerized in an aqueous medium. Therefore, the dispersed particles of the chlorinated polyolefin are Since it is much smaller than the chlorinated polyolefin dispersion particles in the existing flocking adhesive that mixes chlorinated polyolefin emulsion and acrylic emulsion, the emulsion particles are less likely to be destroyed by aggregation of the dispersed particles, and stored for a long time. There is almost no change in the physical properties even when the adhesive is used.Since this adhesive does not contain any organic solvent such as toluene or xylene, these organic solvents do not accumulate in the human body when used for spray coating. , Safe work becomes possible. Further, according to the present invention, the production cycle time is greatly shortened as compared with the conventional concentration method, so that a low-cost water-dispersed adhesive agent for flocking can be obtained. Furthermore, since the conventional flocking adhesive is applied thickly, the smoothness of the adhesive application surface is poor, and the finished state of the surface after flocking is not good.However, by using the adhesive of the present invention, Since it has a strong force, it can be applied thinly, the smoothness of the adhesive surface is good, and the appearance after flocking is remarkably beautiful.

Claims (1)

[Claims] 1. An acrylic or methacrylic system [hereinafter abbreviated as (meth) acrylic system] capable of dissolving chlorinated polyolefins (A) and (A) chlorinated in a chlorine content range of 5 to 70% by weight. ] One or a mixture of two or more types of monomers (B) and (meth) acrylic oligomers (C)
(Meth) acrylic modified chlorinated polyolefin obtained by polymerizing a solution consisting of, in the presence of a catalyst or an emulsion stabilizer, in a water medium. Dispersive flocking adhesive.