JPH06128546A - Adhesive composition - Google Patents

Abstract

PURPOSE:To provide a new adhesive composition which can stick a structural material such as a tile to an upright surface without allowing the stuck material to displaced, is excellent in workability and economic profitability, and can give a cured product excellent in flexibility and durability. CONSTITUTION:The title composition contains an epoxy resin and a silicon compound having an epoxy-reactive functional group and a reactive silicon group in the molecule, and comprises 100 pts.wt. silicon compound, 30-70 pts.wt. epoxy resin, 50-0 pts.wt. colloidal calcium carbonate, 20-50 pts.wt. heavy calcium carbonate, 2-8 pts.wt. organic antisagging agent, 5-15 pts.wt. hydrophobic fine silica powder, 0.5-3 pts.wt. organotin catalyst, and 2.5-4.5 pts.wt. curing agent for epoxy resin.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION 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 in the molecule and a reactive silicon group (hereinafter referred to as a modified silicon compound). In particular, the present invention relates to an adhesive composition which is excellent in flexibility and durability, and is resistant to misalignment when a tile or the like is adhered to an adherend surface extending in a vertical direction and has a long pot life.

2. Description of the Related Art An adhesive having rubber elasticity after curing can absorb strain when an external force is applied, and is therefore suitable as an adhesive for attaching structural materials such as tiles. An example of an adhesive composition that gives such a soft cured product is disclosed in JP-A-61-268720.

In this prior art, the brittleness of an epoxy resin cured product is obtained by compounding an epoxy resin with a rubber organic polymer containing at least one reactive silicon group in the molecule and the above-mentioned modified silicon compound. It is described that the softness of the cured product is obtained.

Further, JP-A-4-100881 discloses that an adhesive composition of this type is used as an adhesive used for adhering a tile or the like to an adherend surface extending in the vertical direction.

However, in the conventional formulation example of the adhesive composition containing the epoxy resin and the modified silicone compound, when the adhesive composition is prepared as a two-component adhesive, it becomes very difficult to mix and apply the adhesive, and the work is difficult. It was difficult in terms of sex.
That is, since the viscosity of the adhesive becomes extremely high in a short time, there is a problem that the coating work, the bonding work, the cleaning work of tools and the like must be performed in a short time. Further, since the adhesive that exceeds the pot life is discarded, there is a problem in economic efficiency.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and an object thereof is to prevent the adherend from being displaced when a structural material such as a tile is attached to a vertical surface. Another object of the present invention is to provide a novel adhesive composition which is excellent in workability and economical efficiency, and gives a cured product having excellent flexibility and durability.

[0006]

Means for Solving the Problems As a result of intensive studies, the inventors of the present invention have studied variously by mixing various fillers and diluents in various proportions with respect to (b) epoxy resin and (a) modified silicon compound. h) It was found that the above problems can be achieved by mixing a curing agent for an epoxy resin in a specific ratio, and the present invention has been completed based on this finding.

That is, the adhesive composition of the present invention is an adhesive composition containing an epoxy resin and a silicon compound (a) having a functional group capable of reacting with an epoxy group and a reactive silicon group in one molecule. There, the (a) silicon compound 100
(B) 30 to 70 parts by weight of epoxy resin, (c) 50 to 90 parts by weight of colloidal calcium carbonate, based on parts by weight.
(D) 20 to 50 parts by weight of heavy calcium carbonate, (e) 2 to 8 parts by weight of organic anti-sagging agent, (f) hydrophobic fine silica powder 5
To 15 parts by weight, (g) 0.5 to 3 parts by weight of an organotin catalyst, and (h) 2.5 to 4.5 parts by weight of a curing agent for an epoxy resin are included, whereby the above object is achieved. To be achieved.

The present invention will be described in detail below. The modified silicon compound (a) used in the present invention is, as described above, a silicon compound containing a functional group capable of reacting with an epoxy group and a reactive silicon group in one molecule, and has the adhesive composition of the present invention. It is added in order to give flexibility to the cured product obtained from the product.

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 means a group which can be crosslinked by a silanol condensation reaction containing a silicon atom to which a hydrolyzable group or a hydroxyl group is bonded. As such a group, for example, a methyldimethoxysilyl group disclosed in JP-A-61-268720 is used.

As the modified silicon compound (a),
For example, the compound represented by the following structural formula may be mentioned.
It should be noted that this molecule contains one or more NH ₂ groups, and in order to show this, (to NH ₂ ) is described below in the structural formula.

[0012]

[Chemical 1]

Commercially available products of the modified silicon compound represented by the above structural formula are, specifically, "Cyryl 5B25" or "Cyryl 5B30" (molecular weight 50, manufactured by Kanegafuchi Chemical Co., Ltd.).
00 to 10000) and the like.

The adhesive composition of the present invention contains an epoxy resin (b) in order to enhance the strength of the adhesive after curing. Examples of the epoxy resin (b) used in the present invention 2 include epichlorohydrin-bisphenol A type epoxy resin, epichlorohydrin-bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin and urethane modified epoxy resin. The epoxy resin is not limited to the above epoxy resin, and widely used epoxy resins can be widely used.

Among these epoxy resins (b), it is particularly preferable to use an epoxy resin having a plurality of epoxy groups in one molecule from the viewpoint of reactivity upon curing.

The adhesive composition of the present invention contains colloidal calcium carbonate (c) as a thickener. Examples of colloidal calcium carbonate (c) that can be used include fatty acid-based, silicic acid-based, and sulfonic acid-based, and the use of fatty acid-based colloidal calcium carbonate is preferable in order to enhance thixotropic properties.

In the present invention, if the compounding amount of the colloidal calcium carbonate (c) is small, the thixotropic improvement effect is insufficient, and if it is too large, the durability of the cured product decreases, so 100 parts by weight of the modified silicon compound (a) is used. 5 for department
It is limited to 0 to 90 parts by weight.

In the adhesive composition of the present invention, heavy calcium carbonate (d) is blended as a thickener, and the heavy calcium carbonate (d) having various particle diameters may be used. it can. Further, in order to enhance the durability of the cured adhesive, it is preferable to use heavy calcium carbonate that has not been surface-treated.

In the present invention, if the blending amount of the above-mentioned heavy calcium carbonate (d) is small, the thixotropic effect is small, and if the blending amount is too large, the viscosity becomes too high. Therefore, relative to 100 parts by weight of the modified silicon compound (b). 20-50
Limited to parts by weight.

In the adhesive composition of the present invention, an organic anti-sagging agent (e) is added in order to enhance thixotropy and prevent sagging of the adhesive. Examples of the organic anti-sagging agent (e) that can be used include vegetable polymerized oil-based, hydrogenated castor oil, fatty acid amide wax-based, and the like, but hydrogenated castor oil-based is preferable for enhancing thixotropy.

In the present invention, when the amount of the organic anti-sagging agent (e) is increased, the cured product becomes brittle, so the amount is limited to 2 to 8 parts by weight with respect to 100 parts by weight of the modified silicon compound (b).

In the adhesive composition of the present invention, the hydrophobic finely divided silica (f) is blended in order to enhance the strength of the cured product, and normally a particle size of about 0.007 μm is used. . As the hydrophobic fine powder silica (f), those surface-treated with CH ₃ group, silicon oil, octylsilane or the like are used.

In the present invention, if the blending amount of the above-mentioned hydrophobic fine powder silica (f) becomes large, the cured product becomes too hard, so that it is 5 per 100 parts by weight of the modified silicon compound (b).
Limited to ~ 15 parts by weight.

In the adhesive composition of the present invention, an organotin catalyst (g) is blended as a catalyst for curing the modified silicon compound (a). Examples of the organic tin catalyst (g) used include butyltin laurate type and butyltin phthalate type.

In the present invention, if the compounding amount of the above organotin catalyst (g) is small, the thixotropic effect is small, and if it is too large, the thixotropic effect is saturated and the durability of the cured adhesive is adversely affected. , Modified silicon compound (b) 1
It is limited to 0.5 to 3 parts by weight with respect to 00 parts by weight.

In the adhesive composition of the present invention, a curing agent (h) for epoxy resin is blended in order to cure the epoxy resin (b). Examples of the curing agent (h) used include polyethylenetetramine, tetraethylenepentamine, diethylaminopropylamine, N-aminoethylpiperazine, isophoronediamine, and 2,4,6-tris (dimethylaminoethyl) phenol.

In the present invention, when the compounding amount of the epoxy resin curing agent (h) is small, the effect of imparting curability is small, and it becomes difficult to impart sufficient strength to prevent the adherend such as tiles from falling. However, since the workability is adversely affected if it increases, it is limited to 2.5 to 4.5 parts by weight with respect to 100 parts by weight of the modified silicon compound (b).

When the adhesive composition of the present invention is constituted as a two-component type adhesive, the above epoxy resin curing agent (h) is different from one reagent mixed with the epoxy resin (b) in the other. It is contained in the reagent.

The adhesive composition of the present invention is usually prepared as a two-component adhesive which is mixed at the time of use. When the two-component adhesive is used, the proportion of the compound is preferably within the following range. Agent A: Modified silicon compound (a) 100 parts by weight, colloidal calcium carbonate (c) 5 to 15 parts by weight, organic anti-sagging agent (e) 2 to 8 parts by weight, hydrophobic fine powder silica (f) 2 to
8 parts by weight and (h) epoxy resin curing agent 2.5 to 4.5
Parts by weight.

Agent B: 100 parts by weight of epoxy resin (b), 40 to 80 parts by weight of colloidal calcium carbonate (c),
20 to 50 parts by weight of heavy calcium carbonate (d), 2 to 8 parts by weight of hydrophobic finely divided silica (f), and an organic tin catalyst (g) of 0.
5 to 3 parts by weight.

Agent A and agent B blended in the above proportions
In the case of agents, agents A and B can be mixed relatively easily during on-site construction for bonding structural materials such as tiles,
It is also possible to prepare the agent A and the agent B by mixing them in a volume ratio of 1: 1. In this way, if the composition is such that the agent A and the agent B can be mixed at a volume ratio of 1: 1,
It is possible to easily mix and use the agents A and B on site without weighing them.

In the agent A, the organic anti-sagging agent (e), the colloidal calcium carbonate (c) and the hydrophobic finely divided silica (f) each have a function of enhancing thixotropy.
Among these, when the compounding amount of the organic anti-sagging agent (e) is increased, the cured product becomes brittle and colloidal calcium carbonate (c)
If the compounding amount of the hydrophobic fine silica (f) is increased, the cured product tends to be brittle. Therefore, it is preferable to mix these various agents within the above numerical range.

On the other hand, in the agent B, the heavy calcium carbonate (d) and the organotin catalyst (g) are the epoxy resin (b).
It plays a role in enhancing and increasing thixotropy. Further, when the blending ratio of the heavy calcium carbonate (d) is increased, the viscosity is significantly increased. Therefore, by adding the colloidal calcium carbonate (c) and the hydrophobic finely divided silica (f), thixotropic properties can be obtained. There is.

Further, if the amount of colloidal calcium carbonate (c) is increased, the durability is lowered, and if the amount of hydrophobic finely divided silica (f) is increased, the cured product tends to be too hard. Therefore, it is preferable that the colloidal calcium carbonate (c) and the hydrophobic fine powder silica (f) are blended in the above blending ratios.

[0035]

EXAMPLES Examples of the present invention will be described below. 1) Preparation of Adhesive Composition As Examples 1 to 5 and Comparative Examples 1 to 3, Agent A and Agent B were blended in the proportions shown in Table 1 below. Table 1
The contents of the various compounding agents therein are as follows. -Modified silicon compound: "Cyril 5B2" manufactured by Kanegafuchi Chemical Co., Ltd.
5 "and" Cyryl 5B30 "-Epoxy resin:" Epicoat 828 "manufactured by Yuka Shell Epoxy Co., Ltd. (component: bisphenol A type glycidyl ether) -Curing agent for epoxy resin (tertiary amine):" DMP- manufactured by Rohm and Haas " 30 "[component: 2,4,6-tris (dimethylaminomethyl) phenol] -organotin catalyst:" SB-65 "(component: dibutyltin dilaurate + dibutyltin oxide) manufactured by Sankyo Machine Co., Ltd.-colloidal sodium carbonate: Maruo Calcium "Calfine 200M" ・ Heavy calcium carbonate: Shiraishi Kogyo "Whiten S"
B "-Organic sagging preventive agent:" Disparlon # 30 "manufactured by Kusumoto Kasei Co., Ltd.
5 "(component: castor oil hydrogenated oil) -hydrophobic fine powder silica:" Aerosil R-202 "manufactured by Nippon Aerosil Co., Ltd.

2) Evaluation of Adhesive The adhesive prepared by mixing the agents A and B in the ratio shown in Table 1 was evaluated by the following method, and the results are shown in Table 1. (1) Pot life: A total of 400 g of modified silicone compounding agent (A agent) and epoxy resin compounding agent (B agent) was placed on a plate, and the two liquids were mixed with a spatula and placed in an oven at 40 ° C. It was warmed up and sensory evaluated the dry time by touching with a finger. (2) Curing flexibility: 70 mm of a mixture of agents A and B
After being cast in a size of 40 mm x 2.5 mm and cured at room temperature for 2 days, it is cured in a constant temperature bath at 50 ° C for 2 days to cure, and then the cured product is bent and the teared state is functionalized. evaluated. (3) Tile misalignment: 1.2 kg / m of adhesive is applied to a board extending vertically by using a 5 mm square sharpening iron.
^It is applied so that the ratio becomes ² , then 60 mm ×
225mm x 8mm thick, 250g weighted backing tiles are stacked and glued to a board extending in the vertical direction,
The misalignment in the initial state of adhesion was visually evaluated.

[0037]

[Table 1]

As is clear from Table 1, the adhesives having the compounding ratios of Examples 1 to 5 all had a long pot life,
It can be seen that the flexibility after curing is also excellent and the tile is not displaced. On the other hand, it is understood that the adhesives having the compounding ratios of Comparative Examples 1 to 3 cannot satisfy any of the pot life, the curing flexibility, and the tile shift.

[0039]

As described above, according to the present invention, since the pot life of the adhesive is extended, the economical efficiency is improved, and not only the flexibility after curing is excellent, but also When bonding structural materials such as tiles to the vertically extending surface,
It is possible to obtain an adhesive that is less likely to cause structural material displacement. Moreover, when configured as a two-component adhesive, it is possible to provide an adhesive for on-site construction which is excellent in workability and which can smoothly perform mixing, coating work and tool cleaning work.

Claims (1)

[Claims] 1. An adhesive composition comprising an epoxy resin and a silicon compound (a) having a functional group capable of reacting with an epoxy group and a reactive silicon group in one molecule, wherein the (a) silicone is used. (B) 30 to 70 parts by weight of epoxy resin, (c) 50 to 90 parts by weight of colloidal calcium carbonate, and (d) heavy calcium carbonate 2 to 100 parts by weight of the compound.
0 to 50 parts by weight, (e) organic sagging inhibitor 2 to 8 parts by weight,
(F) 5 to 15 parts by weight of finely divided hydrophobic silica, (g) 0.5 to 3 parts by weight of an organotin catalyst, and (h) 2.5 to 4.5 parts by weight of a curing agent for epoxy resin. Adhesive composition.