JPH0721132B2 - Emulsion adhesive composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel emulsion adhesive composition, and more specifically, it has excellent initial adhesiveness and adhesive strength after construction, and after a long period of time after construction. The present invention also relates to an emulsion adhesive composition suitable as an adhesive for polyvinyl chloride flooring that does not cause discoloration of the flooring.

(Prior art) As flooring materials for concrete buildings, polished granite, tufted carpets, polyvinyl chloride flooring materials, etc. are generally used. Among them, polyvinyl chloride flooring materials are used. It is widely used as the mainstream of flooring materials because it is easy to use and the color and design can be freely selected.

As a floor material made of polyvinyl chloride, a hard vinyl asbestos tile made of polyvinyl chloride mixed with a large amount of asbestos powder and a relatively small amount of a plasticizer has been generally used. Due to the above problems, the use of asbestos is restricted, and because of the comfort and the aesthetic appeal when walking, it is composed of a polyvinyl chloride foam layer and a soft polyvinyl chloride layer containing a large amount of plasticizer. The so-called cushion floor has come to be used as a floor material.

For the construction of flooring made of polyvinyl chloride, a conjugated diene rubber latex is usually blended with a hydrocarbon resin emulsion as a tackifier, and further a plasticizer such as broths oil and a filler such as calcium carbonate are added and dispersed if desired. It is carried out by directly adhering to the concrete floor surface using an adhesive agent containing an agent, a defoaming agent, an antiseptic agent, a thickening agent and the like. The required performance for such an adhesive is that it retains sufficient adhesiveness within a certain period of time after being applied to the floor material until it is adhered to the concrete floor surface, that is, it has excellent initial adhesiveness, and after the construction. Also has sufficient adhesive strength. In order to obtain high adhesive strength after construction, for example, as a resin component of the adhesive, an adduct of a hydrocarbon resin copolymerized with a C ₅ fraction and styrenes and an ethylenically unsaturated carboxylic acid or an anhydride thereof is used. Methods (Japanese Patent Publication No. 59-2697) and methods of reducing the amount of plasticizer in the adhesive have been proposed. However, these methods have a drawback that sufficient initial adhesion cannot be obtained. On the other hand, if the amount of plasticizer is increased to improve the initial adhesiveness, not only will sufficient adhesive strength not be obtained after construction, but if such an adhesive is used for soft polyvinyl chloride flooring, the time after construction will be reduced. It has become clear that there is a problem that the discoloration of the flooring material occurs with the progress of the above, and the appearance is seriously damaged. Such a phenomenon is particularly remarkable under the condition that the floor material has a high temperature or receives direct sunlight.

(Problems to be Solved by the Invention) Then, as a result of intensive studies to solve such a drawback of the conventional technique, the inventors of the present invention thermally polymerized a monomer mixture having a specific composition as a resin component of an adhesive. By using the hydrocarbon resin obtained by the above, it is possible to obtain an adhesive composition which is excellent in initial adhesiveness and adhesive force after construction, and does not have a risk of discoloring the floor surface even after a long period of construction. Find out that
The present invention has been completed.

(Means for Solving the Problems) Thus, according to the present invention, (A) a conjugated diene rubber latex is added as a tackifier (B) a cyclopentadiene monomer in an amount of 35 to 80% by weight and a polar vinyl compound in an amount of 5 to 30% by weight. There is provided an emulsion adhesive comprising a hydrocarbon resin obtained by thermally polymerizing a monomer mixture containing 10% by weight and 10 to 50% by weight of a chain conjugated diene.

The conjugated diene rubber latex used in the present invention is a latex of a rubber containing a conjugated diene as a main component, and specifically, natural rubber, synthetic cis-1,4 polyisoprene rubber, styrene-butadiene copolymer rubber, styrene. -The isoprene copolymer rubber, styrene-butadiene block copolymer rubber, styrene-isoprene block copolymer rubber, etc. These may be those directly synthesized by emulsion polymerization or those obtained by phase inversion of rubber obtained by solution polymerization. Among these rubber latex, in terms of performance, the natural rubber latex and the bound styrene content obtained by emulsion polymerization are 20 to 70% by weight,
Preferably 30-60% by weight of styrene-butadiene copolymer rubber latex is used.

On the other hand, the hydrocarbon resin used as a tackifier in the present invention is a cyclopentadiene monomer 35 to 80% by weight, preferably 40 to 75% by weight, a polar vinyl compound 5 to 30% by weight,
It is obtained by thermal polymerizing a monomer mixture containing preferably 10 to 25% by weight and a chain conjugated diene 10 to 50% by weight, preferably 15 to 45% by weight.

At this time, when the content of the cyclopentadiene-based monomer is smaller than the above range, the yield of the resin as a product is remarkably lowered, and the softening point of the resin is remarkably lowered, which is It is not possible to obtain sufficient adhesive strength. On the contrary, if the content of the cyclopentadiene-based monomer is too large,
The softening point of the resin becomes extremely high, and the object of the present invention to obtain an adhesive having excellent initial adhesiveness cannot be achieved.

Also, when the polar vinyl compound is almost not contained,
The initial adhesiveness of the adhesive is not sufficiently improved, and particularly when the rubber latex component of the adhesive is a styrene-butadiene copolymer, not only the initial adhesiveness but also the adhesive strength is deteriorated, which is not preferable. On the other hand, when the polar vinyl compound is excessively abundant, the hue of the resin as a product is deteriorated, which may cause coloration or a by-product of a low molecular weight polymer having an odor, which deteriorates the odor of the resin. Not preferable.

Further, the chain conjugated diene has a remarkable effect in adjusting the molecular weight distribution of the resin and improving the initial adhesiveness with the adhesive without impairing the hue and odor of the resin, but the chain conjugated diene in the monomer mixture is If the diene content is excessively increased, the resin yield will be remarkably lowered, and the softening point will be remarkably lowered, so that sufficient adhesive force cannot be imparted to the adhesive.

In the present invention, other saturated hydrocarbons or unsaturated hydrocarbons can be contained in the monomer mixture in a total amount of up to 25% by weight.

Polymerization is usually performed at 200 to 300 ° C, preferably 240 to 280 ° C.
It takes 5 to 20 hours.

During the polymerization, an inert hydrocarbon solvent such as benzene, toluene and xylene can be optionally used.

The cyclopentadiene-based monomer used in the present invention means cyclopentadiene or a derivative thereof, and examples thereof include cyclopentadiene, dicyclopentadiene and methylcyclopentadiene dimer, and a mixture thereof.

The polar vinyl compound is a lower fatty acid ester of an unsaturated alcohol such as vinyl acetate, vinyl bromopionacetate, allyl acetate, allyl bropionate, acrylic acid, etc.
Examples thereof include unsaturated carboxylic acids such as methacrylic acid, esters of the above unsaturated carboxylic acids and lower alcohols such as methyl alcohol, ethyl alcohol, butyl alcohol, etc. Among them, vinyl acetate, ethyl acrylate and methyl methacrylate are the prizes. Used.

Examples of chain conjugated dienes include 1,3-pentadiene, isoprene, and 1,3-butadiene. The chain conjugated diene need not be particularly highly purified and may be used in the form of a hydrocarbon mixture containing other saturated hydrocarbons or unsaturated hydrocarbons.

The hydrocarbon resin used in the present invention is usually processed into an emulsion and mixed with a conjugated diene rubber latex. The ratio is 100 to 300 parts by weight of the conjugated diene rubber solid content, hydrocarbon resin 20 to 300 parts by weight, preferably 40 to 150 parts by weight.
If the amount is parts by weight and the amount is out of this range, an adhesive having sufficient adhesion performance cannot be obtained.

In the present invention, in addition to the conjugated diene rubber and the hydrocarbon resin, other base polymers and tackifier resins can be used in combination within a range that does not impair the effects of the present invention, and further process oil according to a conventional method. A plasticizer such as, a filler such as calcium carbonate, a dispersant, a defoaming agent, an antiseptic, an antioxidant, a thickener, and the like can be appropriately mixed.

(Effect of the invention) The emulsion composition obtained according to the present invention is
It has the advantages of excellent initial adhesiveness and adhesive strength, low odor, and light hue. Therefore, it is particularly suitable as an adhesive for flooring materials, in which case it does not cause discoloration of the flooring surface even under conditions such as high temperature or exposure to sunlight after construction, which may impair the aesthetics of the floor surface. It also has the advantage of not being.

(Example) Hereinafter, the present invention will be described more specifically with reference to Examples. In addition, parts and% in the examples, comparative examples and reference examples are based on weight unless otherwise specified.

Reference example A pressure-resistant autoclave was charged with a monomer mixture having the composition shown in Table 1, and heat-polymerized at 260 ° C for 4 hours in a nitrogen atmosphere, followed by distillation under reduced pressure at 250 ° C and 5 mmHg to obtain an unreacted monomer. A low boiling point substance including an oily product was distilled off to obtain a hydrocarbon resin. The yield and properties of the resin were measured, and the results are shown in Table 1.

Example 1 The hydrocarbon resins listed in Table 1 were used and the emulsion was adjusted. To prepare emagyon, first add 50 parts of mineral spirits to 100 parts of resin, dissolve by stirring, and then add 9 parts of nonionic surfactant (Nonipol 100, Sanyo Kasei Co., Ltd.). High-speed stirring was performed with a homogenizer. Water was gradually added while continuing stirring to obtain a hydrocarbon resin emulsion (solid content concentration 65%).

Natural rubber latex 10 in this hydrocarbon resin emulsion
0 parts (as rubber content), 50 parts of naphthenic process oil (Futsucor 2050N, manufactured by Fuji Kosan Co., Ltd.) and 400 parts of heavy calcium carbonate were added to obtain an adhesive composition having a solid content concentration of 75%.

The obtained adhesive composition was applied to a cushion floor material with a thickness of 2.3 mm (manufactured by Toyo Reno Liume Co., Ltd., CF.P
1537) on the back side, affixed to the slate plate after 10 minutes and allowed to cure for 24 hours under the conditions of temperature 20 ° C and relative humidity 65%, and then 180 ° C peeling test (pulling speed 300mm / min). It carried out and evaluated the adhesive force.

In addition, the cushion floor material coated with adhesive is
After being left for 60 minutes at a temperature of 65 ° C. and a relative humidity of 60%, it was adhered to a slate plate, and a peeling test was carried out under the same conditions and methods as in the evaluation of the adhesive force to evaluate the initial adhesiveness.

Furthermore, a certain amount of adhesive is applied to the back surface of the floor material, and a carbon arc beam is applied to the surface of the floor material using a weather meter (Gas Tester Co., Ltd., WEL-HC),
Further, an accelerated deterioration test was carried out with the temperature kept at 63 ° C., and the presence or absence of discoloration of the floor material surface was evaluated after 20 hours and 40 hours.

The results are shown in Table 2.

As the resin component of the adhesive used for the evaluation, in addition to the resin obtained in Reference Example, a commercially available hydrocarbon resin, Quinton D-100 (manufactured by Nippon Zeon Co., Ltd., softening point 9
9 ° C., Gardner chromaticity 3) and Hiresin 60 (manufactured by Toho Petroleum Resin Co., Ltd., softening point 65 ° C., Gardner chromaticity 6) were used.

The results are shown in Table 2.

Example 2 As a conjugated diene rubber component, styrene-butadiene copolymer latex (LX-472, bound styrene content 50%,
An adhesive composition was prepared in the same manner as in Example 1 except that a gel content of 40%, manufactured by Nippon Zeon Co., Ltd. was used, and the adhesive strength, the initial adhesiveness, and the presence or absence of discoloration of the floor material surface were evaluated. . The results are shown in Table 3.

From Tables 2 and 3, it can be seen that the examples of the present invention have excellent adhesive strength and initial adhesiveness, and do not discolor the floor material surface even under severe environmental conditions.

On the other hand, when a hydrocarbon resin containing no polar vinyl compound was used (Experiment Nos. 1-6 and 2-6), the initial adhesiveness was significantly reduced, and the rubber latex component of the adhesive had a styrene-butadiene copolymer weight. It can be seen that when the combined latex is used (Experiment No. 2-6), the adhesive force also decreases. On the contrary, when a hydrocarbon resin containing an excessive amount of a polar vinyl compound is used (Experiment Nos. 1-7 and 2-7), it is not possible to prevent discoloration of the floor material surface. In addition, when a hydrocarbon resin having a large content of cyclopentadiene-based monomer was used (Experiment Nos. 1-8 and 2-8), the adhesive strength and the initial adhesive strength were poor, and especially styrene was used as the rubber latex component of the adhesive. It can be seen that when the butadiene copolymer latex is used (Experiment No. 2-8), the initial adhesive strength is significantly reduced. On the contrary, when a hydrocarbon resin having a small cyclopentadiene monomer content and a large chain conjugated diene content is used (Experiment Nos. 1-9 and 2-9), the adhesive strength is significantly reduced. I understand.

Claims (1)

[Claims] 1. A conjugated diene rubber latex (A) 35 to 80% by weight of a (B) cyclopentadiene monomer as a tackifier based on 100 parts by weight of a rubber solid content in the conjugated diene rubber latex. A hydrocarbon resin obtained by thermal polymerization of a monomer mixture containing 5 to 30% by weight of a polar vinyl compound and 10 to 50% by weight of a chain conjugated diene. Emulsion adhesive composition.