JPH05287256A - Adhesive composition - Google Patents

Abstract

PURPOSE:To obtain an elastic adhesive good in workability such as takeout, miscibility and applicability at low temperatures in winter or the like. CONSTITUTION:This composition comprises 100 pts.wt. silicon compound containing epoxy-reactive functional groups and reactive silicon groups in the molecule, 15-40 pts.wt. epoxy resin, 3-20 pts.wt. colloidal light calcium carbonate, 2-8 pts.wt. organic antisagging agent, 2-10 pts.wt. fine hydrophobia silica powder, 25-55 pts.wt. fine calcium carbonate powder, 10-40 pts.wt. fine surface-treated calcium carbonate powder, 0.5-5 pts.wt. organic bentonite, and 0.5-4 pts.wt. organotin catalyst.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an adhesive composition containing an epoxy resin and a silicon compound having a functional group capable of reacting with an epoxy group and a reactive silicon group in the molecule (hereinafter referred to as a modified silicon compound). The present invention relates to an adhesive composition suitable for bonding tiles and the like.

[0002]

2. Description of the Related Art An adhesive that exhibits rubber elasticity after curing can absorb strain when external force is applied, and is therefore suitable for attaching structural materials such as tiles. As such an adhesive, for example, JP-A-61-268720,
It has been proposed to blend an epoxy resin with a rubber-based organic polymer having at least one reactive silicon group in the molecule and a modified silicon compound. According to this formulation, the brittleness of the epoxy resin cured product is improved, whereby a flexible cured product is obtained.

Also, as an adhesive composition which gives a cured product having the same flexibility, a composition in which the above modified silicon compound is mixed with an epoxy resin is known. (Katsuhiko Isayama, Adhesion, 32 (4), 149 (1988)). Conventional such adhesive compositions include ground calcium carbonate, colloidal calcium carbonate, hydrophobic finely divided silica and / or
Alternatively, various fillers such as an organic anti-sagging agent may be blended to prevent sagging when the adhesive is applied. However, in such a conventional adhesive composition, although the sagging at the time of adhering the adhesive itself is prevented, when a structural material such as a tile is attached to an adherend surface extending in the vertical direction, the structural material Immediately shifted downward and was unsuitable as an adhesive for on-site construction.

By including a large amount of filler in such an adhesive composition, it is possible to prevent the displacement of tiles and the like during adhesion. However, when the content of the filler is increased, the viscosity of the adhesive becomes very high, and when it is prepared as a two-component adhesive, it becomes very difficult to mix and apply the adhesive. , There was a problem in workability. Further, when the content of the filler is increased, there is a problem in that the flexibility after curing is lowered, and the advantage of blending the modified silicon compound that imparts flexibility to the cured product is impaired.

[0005]

The inventor of the present invention has found that the above problems can be solved by mixing a specific filler in a specific ratio with respect to the epoxy resin and the modified silicon compound. After completing the invention, a patent application was filed (Japanese Patent Application No. 2-217295). The adhesive composition of the present invention contains epoxy resin 30 to 70 parts by weight, colloidal calcium carbonate 50 to 90 parts by weight, and heavy calcium carbonate 20 to 20 parts by weight with respect to 100 parts by weight of the modified silicon compound.
50 parts by weight, an organic anti-sagging agent 2 to 8 parts by weight, hydrophobic fine powder silica 5 to 15 parts by weight, and an organic tin catalyst 0.5 to 0.3 parts by weight are included, and the flexibility and durability are improved. It is good and excellent in that no deviation occurs when a tile or the like is adhered to the adherend surface extending in the vertical direction.

This adhesive composition can also be used as an adhesive for line construction in order to attach a tile or the like on a flat surface such as a floor. However, when this adhesive composition is used at a low temperature (for example, 5 ° C.) such as in winter, the viscosity is very high, and the adhesive take-out property, mixing property, and
Also, there is a problem that workability such as coating property is significantly deteriorated. An object of the present invention is to provide an adhesive composition that does not impair workability even at low temperatures such as winter.

The adhesive composition of the present invention contains an epoxy resin and a silicon compound having a functional group capable of reacting with an epoxy group and a reactive silicon group in one molecule, and is based on 100 parts by weight of the silicon compound. Epoxy resin 15-40
Parts by weight, colloidal light calcium carbonate 3 to 20 parts by weight,
Organic anti-sagging agent 2-8 parts by weight, hydrophobic fine powder silica 2-1
0 parts by weight, 25 to 55 parts by weight of finely divided calcium carbonate, 10 to 40 parts by weight of surface-treated finely divided calcium carbonate, 0.5 to 5 parts by weight of organic bentonite, and 0.5 to 4 parts by weight of organic tin catalyst. There is. Hereinafter, the present invention will be described in more detail.

Epoxy Resin In the adhesive composition of the present invention, an epoxy resin is blended in the above proportion in order to enhance the strength of the adhesive after curing.
Examples of the epoxy resin used in the present invention include epichlorohydrin-bisphenol A type epoxy resin, epichlorohydrin-bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin and urethane modified epoxy resin, and the like. However, the epoxy resin that is generally used can be widely used. However, from the viewpoint of reactivity upon curing, it is preferable to use an epoxy resin having a plurality of epoxy groups in one molecule.

It goes without saying that a curing agent for curing the epoxy resin may be added to the adhesive composition of the present invention. Examples of such epoxy resin curing agents include polyethylene tetramine, tetraethylene pentamine, diethylaminopropylamine, N-aminoethylpiperazine, isophoronediamine, 2,4.
6-tris (dimethylaminomethyl) phenol and the like can be mentioned. When the adhesive composition of the present invention is configured as a two-component adhesive, the epoxy resin curing agent as described above is contained in the other reagent that is different from one reagent in which the epoxy resin is mixed.

Modified Silicon Compound In the present invention, the modified silicone compound is a silicone compound containing a functional group capable of reacting with an epoxy resin and a reactive silicon group in one molecule as described above. It is added in order to give flexibility to the cured product obtained from the composition.

As the functional group capable of reacting with the epoxy group,
Examples thereof include an amino group, a mercapto group, an epoxy group and a carboxyl group. The reactive silicon group refers to a hydrolyzable group or a group containing a silicon atom to which a hydroxyl group is bonded and which can be crosslinked by a silanol condensation reaction. Typically, a methyldimethoxysilyl group as disclosed in JP-A-61-268720 can be mentioned. The modified silicon compound as described above is specifically, a brand name manufactured by Kanegafuchi Chemical Industry Co., Ltd .: Cyril 5B25 or Cyryl 5
Commercially available as B30.

Calcium Carbonate In the adhesive composition of the present invention, colloidal light calcium carbonate, finely divided calcium carbonate and surface-treated finely divided calcium carbonate are blended in the above-mentioned specific proportions as fillers for calcium carbonate. In the present invention, colloidal light calcium carbonate is light calcium carbonate in a special dispersed state, and has an average particle diameter of 0.1 to 10 μm and 0.2 g.
It has a specific gravity of about / ml. Fine calcium carbonate is obtained by further crushing light calcium carbonate, and has an average particle diameter of 0.07 to 0.15 μm and 0.2
It has a specific gravity of 5 to 0.4 g / ml.

The surface-treated finely powdered calcium carbonate refers to the surface of the above-mentioned colloidal light calcium carbonate coated with a fatty acid salt, a rosin salt or the like. The amount of the colloidal light calcium carbonate blended is set to 3 to 20 parts by weight. When the amount is less than 3 parts by weight, sufficient structural viscosity cannot be obtained and the composition has an elongation property, resulting in poor thread breaking property. As a result, structural materials such as tiles attached to the vertical surface are displaced downward. If it is blended in an amount of more than 20 parts by weight, the structural viscosity becomes too high, and the mixing work as a two-component adhesive becomes difficult, and the trowel coatability at the time of coating becomes poor. For the same reason as in the case of the colloidal light calcium carbonate described above, the amount of finely divided calcium carbonate is set to 25 to 55 parts by weight, and the amount of surface-treated finely divided calcium carbonate is set to 10 to 40 parts by weight.

Organic Sagging Prevention Agent An organic sagging prevention agent is added to enhance thixotropy and prevent sagging of the adhesive. Examples of the organic anti-sagging agent that can be used include vegetable polymerized oil type, hydrogenated castor oil type, and fatty acid amide wax type, but hydrogenated castor oil type is preferable in order to enhance thixotropic properties. The organic anti-sagging agent enhances thixotropy, but if it is contained too much, the cured product becomes brittle, so it is blended in the range of 2 to 8 parts by weight as described above.

Hydrophobic finely divided silica Hydrophobic finely divided silica is added to enhance the strength after curing. Usually, a form having a particle size of about 0.007 μm is used. As the hydrophobic fine silica powder, those whose surface is surface-treated with CH ₃ group, silicon oil, octylsilane or the like are used. If the blending amount of the hydrophobic silica is too large, the cured product will be too hard, so that it is blended in the range of 2 to 10 parts by weight as described above.

Organotin Catalyst In the present invention, an organotin catalyst is blended at a specific ratio as a catalyst for curing the modified silicon compound. As an organotin catalyst that can be used, a butyltin laurate type or a butyltin phthalate type is used. Organotin catalyst content of 0.5 to 4
The reason why the amount is less than 0.5 parts by weight is that if it is less than 0.5 parts by weight, a sufficient effect as a catalyst for the modified silicon does not appear, and an uncured portion remains.
This is because the catalytic effect is not improved and the diluting action appears.

Organic Bentonite In the present invention, the organic bentonite is blended to further enhance thixotropy and impart desired viscosity without impairing workability at low temperature. As the organic bentonite used in the present invention, there is a bentonite clay mineral in which a surfactant is allowed to act by ion exchange. The amount of the organic bentonite compounded is 0.5 to 5 parts by weight.
This is because if it is less than 0.5 parts by weight, the effect of imparting thixotropy is not sufficient, and if it exceeds 5 parts by weight, viscosity and thixotropy become high, and the take-out property at low temperature, the mixing property and the coating property are deteriorated.

[0018]

Description of Embodiments Next, embodiments of the present invention will be described. As Examples 1 to 5 and Comparative Examples 1 to 7, Agent A and Agent B were prepared at the ratios shown in Table 1, respectively. The contents of each compounding agent in Table 1 are as follows.

Cyril 5B25 and Cyril 5B3
0: Modified silicon compound (Kanefuchi Chemical Industry Co., Ltd.)-Epicoat 828XA; Bisphenol A type glycidyl ether (Okaka Shell Epoxy Co., Ltd.)-Tertiary amine; 2,4,6-Tris (dimethylaminomethyl) phenol (ROHM) Made by Andhas, product name:
DMP-30) ・ Organotin catalyst SB-65; dibutyltin dilaurate + dibutyltin oxide (manufactured by Sansha Machine Co., Ltd.)

Colloidal light calcium carbonate; Maruo Calcium Co., trade name; Calfine 200M (average particle size 0.07 μm, oil absorption 28 ml / 100 g, fatty acid surface treatment) Organic anti-sagging agent; castor oil hydrogenated oil (Kusumoto Kasei Co., Ltd., trade name: DISPARON # 305) -Hydrophobic finely divided silica; Nippon Aerosil Co., Ltd., trade name: Aerosil R-202-Fine powder calcium carbonate; Nitto Koka Shoji Co., Ltd., trade name: N
CC-45 ・ Surface treatment Japanese calcium carbonate; manufactured by Shiraishi Industry Co., Ltd., trade name: Homocal D (average particle size 0.05 μm, oil absorption 25
ml / 100g, organic active substance surface treatment) -Organic bentonite; manufactured by Shiraishi Industry Co., Ltd., trade name: New D
Orben

[0021]

[Table 1]

Examples 1 to 5 and Comparative Examples 1 to 7 shown in Table 1
For each of the two-component adhesives described in (1), Agents A and B were mixed and used, and evaluated by the following methods. The evaluation results are also shown in Table 1. (A) Curing flexibility: 70 mm x mixture of agents A and B
40 mm × thickness 2.5 mm, cast at room temperature for 2
After being left for one day, it was cured by curing in a constant temperature bath at 50 ° C. for 2 days, then the cured product was bent, and the state of tearing was sensory evaluated. (B) Flexibility after hot water test at 95 ° C .: A mixture of agents A and B was cast into a size of 40 mm × 120 mm × thickness 2.8 mm, left at room temperature for 2 days, and then kept at 50 ° C. After curing in a bath for 2 days to cure, the cured product was immersed in hot water at 95 ° C. for 1 week, and the flexibility of the product after immersion and the product without immersion were sensory evaluated.

(C) Vertical plane tile displacement: A mixture of agents A and B was used for boards extending in the vertical direction.
It is coated on the board with a 5 mm square sharpening iron to a rate of 1.2 kg / m ² , and then 60 mm × 22
Tile with soles 5 mm x thickness 8 mm and weight 250 g 2
The sheets were stacked and adhered, and the deviation in the initial state of adhesion was visually evaluated. (D) Removability at low temperature: A agent and B at low temperature of 5 ° C
A sensory evaluation was performed on the magnitude of resistance applied to the spatula when the agent was removed with a spatula.

(E) Mixability at low temperature: A at low temperature of 5 ° C.
The amount of resistance applied to the spatula when the equal amounts of the agent and the agent B were mixed using a spatula was sensory-evaluated. (F) Applicability at low temperature: When the mixed adhesive was applied to a vertical surface with a comb iron at a low temperature of 5 ° C, the magnitude of resistance applied to the comb iron was sensory evaluated. (G) Vertical surface tile displacement at low temperature: Structural material (vertical 60 mm, horizontal 227 m) on the adhesive applied to the vertical surface with a comb trowel
m, thickness 10 mm: tile having a weight of about 300 g) was attached, and the degree of deviation was visually observed.

As is clear from the results shown in Table 1, the adhesive compositions of Examples 1 to 5 according to the present invention have appropriate viscosity and thixotropy, and take-out property at a low temperature of 5 ° C.
Excellent mixability and coatability.

[0026]

As described above, the adhesive composition of the present invention is
It has moderate thixotropy, is excellent in retrievability, mixability, and coatability even at low temperatures, and does not impair workability even at low temperatures.

Claims (1)

[Claims] 1. An adhesive composition comprising an epoxy resin and a silicon compound having a functional group capable of reacting with an epoxy group and a reactive silicon group in one molecule, which is based on 100 parts by weight of the silicon compound. , Epoxy resin 15 to 40 parts by weight, colloidal light calcium carbonate 3 to
20 parts by weight, organic anti-sagging agent 2 to 8 parts by weight, hydrophobic fine powder silica 2 to 10 parts by weight, fine powder calcium carbonate 25 to 55
An adhesive composition comprising 10 parts by weight, surface-treated finely divided calcium carbonate 10 to 40 parts by weight, organic bentonite 0.5 to 5 parts by weight, and organic tin catalyst 0.5 to 4 parts by weight.