JP2000336333A - Epoxy-based two-pack type adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a solventless adhesive capable of laminating a wide area to a uniform thickness without requiring setting of the open time and capable of carrying out the reapplication without attacking polyvinyl chloride resin, excellent in water resistance and further capable of performing the filling or sealing and surely bonding the polyvinyl chloride resin (especially a flexible one). SOLUTION: This epoxy-based two-pack type adhesive comprises the following ingredients A and B: the ingredient A: a composition consisting essentially of (a) 100 pts.wt. of a urethane-modified epoxy resin having <=50 Pa.s viscosity, (b) 20-80 pts.wt. of one or more kinds of liquid epoxy resins selected from bisphenol A type or bisphenol F type epoxy resins and (c) >=2 pts.wt. of acrylic fine particles having <=1 μm average particle diameter and the ingredient B: a polyamidoamine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-part curable epoxy resin, and more particularly to an epoxy resin adhesive suitable for bonding polyvinyl chloride resin.

[0002]

2. Description of the Related Art Polyvinyl chloride resin is a thermoplastic plastic that generates dioxin when it is burned at a low temperature. In recent years, however, the regulations have been strict and the number of recycling companies has been increasing. In addition, although the polyvinyl chloride resin compound industry has not grown significantly, vinyl chloride resin is used in various aspects of daily life, and it is clear that its performance is steadily increasing.

[0003] As typical adhesives for conventional polyvinyl chloride resin, a one-part solvent-evaporating adhesive obtained by dissolving polyvinyl chloride or rubber in a solvent, or polyvinyl chloride mainly using a solvent is used. Some are melted and adhered.

[0004]

Although commercially available as "for PVC" or "for vinyl chloride", these adhesives have a problem that it is difficult to surely bond them. The reason is that. Since it contains a solvent, an open time is required. Before the open time, the solvent may be trapped in the adhesive surface. . When bonding over a wide area, the solvent is volatilized during the coating, so that bonding cannot be performed with a uniform thickness, or re-bonding cannot be performed, so that wrinkles and bubbles are trapped. . When the polyvinyl chloride resin is a thin film (sheet), the polyvinyl chloride resin is eroded by the solvent, making it impossible to adhere. . Poor water resistance, lack of long-term stable adhesive strength, large thickness of cured meat, and inability to fill and seal.

[0005] Particularly, in the case of a soft polyvinyl chloride resin, even when reliable bonding is performed, the bonding strength is low, and it cannot withstand mechanical stress (shearing and peeling directions). Furthermore, since it contains a solvent, long-term storage stability is poor, and there is a problem in environmental hygiene.

For this reason, there has been an attempt to bond a polyvinyl chloride resin using a reaction type adhesive instead of such a solvent type adhesive, but a material which satisfies the bonding performance has not yet been developed.

Therefore, an object of the present invention is to provide a. No need to set open time with no solvent. A wide area can be stuck to a uniform thickness, and can be stuck again. Does not attack polyvinyl chloride resin. Excellent water resistance. An object of the present invention is to provide an adhesive that can reliably adhere a polyvinyl chloride resin (especially soft) that can be filled and sealed.

[0008]

According to the present invention, an epoxy two-part adhesive comprising the following components: A agent: a 100 parts by weight of a urethane-modified epoxy resin having a viscosity of 50 Pa · s or less, and b bisphenol A type Or one or more liquid epoxy resins selected from bisphenol F type epoxy resins 2
A composition comprising, as main components, 0 to 80 parts by weight, and 2 parts by weight or more of acrylic rubber fine particles having an average particle size of 1 μm or less. Agent B: The above problem of polyamidoamine could be solved.

According to the present invention,. Unlike conventional solvent-based adhesives, no solvent is used, and. Since the pot life depends on the polyamidoamine of the B agent, there is no need to set an open time, and the pasting may be performed before the curing time. Since it is liquid until curing, even if bubbles are trapped in the case of lamination, bubbles can be expelled by using a roller, etc., and the adherend is not attacked. Since it is an epoxy resin, it has excellent water resistance after curing. All problems can be solved, such as filling and sealing can be performed simultaneously with little shrinkage.

The urethane-modified epoxy resin of Agent A used in the present invention may be any epoxy resin having a urethane bond in the molecular chain, and there is no particular limitation on the type and the like. However, the viscosity is 50 from the viewpoint of applicability and adhesion.
Pa · s or less is desirable. Specific examples of this urethane-modified epoxy resin are, for example, trade names: EPU-11, EPU
-15, EPU-16A and EPU-16B (both manufactured by Asahi Denka Kogyo KK).

As the bisphenol A type liquid epoxy resin that can be used in the present invention, conventionally known epoxy resins can be used, and there is no particular limitation as long as it is liquid. For example, Epicoat 828, Epicoat 827 (manufactured by Yuka Shell Epoxy), EP-4100, EP-4300
(Made by Asahi Denka Kogyo), EPICLON840, EPOC
LON850 (manufactured by Dainippon Ink and Chemicals, Inc.) and the like, but if necessary, a reactive diluent such as alkyl monoglycidyl ether or alkylenediglycidyl ether or D
Non-reactive diluents such as BP and DOP may be added.
The bisphenol F type liquid epoxy resin is the same as the bisphenol A type, and a conventionally known one can be used.
For example, Epicoat 807, Epicoat 806 (manufactured by Yuka Shell Epoxy), EP-4901, EP-493
0 (made by Asahi Denka Kogyo), EPICLON 830, EPI
CLON835 (manufactured by Dainippon Ink and Chemicals, Inc.) and the like.

The acrylic rubber fine particles used in the present invention are:
Fine particles comprising a copolymer of methyl methacrylate and glycidyl methacrylate, for example, F340, F345
(Zeon Corporation) or core-shell acrylic microparticles whose core part is made of polybutyl acrylate and whose shell part is mainly polymethyl methacrylate, for example, F351 (manufactured by Zeon Corporation). One or more of these acrylic rubber fine particles are used. The particle size is 1 μm or less, preferably 0.1 to 0.5 μm. The addition amount of the acrylic rubber fine particles is 10 parts by weight with respect to 100 parts by weight of the total amount of the bisphenol A type or F type liquid epoxy resin.
It is used by adding at least part by weight (at least 10% by weight). The upper limit varies depending on the viscosity of the liquid epoxy resin and the particle size of the acrylic rubber fine particles, but is generally about 40 parts by weight, preferably 20 to 30 parts by weight.
If the amount is less than 10 parts by weight, the effect is not clear, and if added in a large amount, the viscosity increases and a problem arises in applicability and the like.

The method for adding the acrylic rubber fine particles may be one or more of the above-mentioned bisphenol A-type or F-type epoxy resin or the urethane-modified epoxy resin or a mixture thereof. The order of addition is not limited.
Preferably, bisphenol A type or F type epoxy resin which is dispersed in one or more liquid epoxy resins in advance is suitable. The particle size of the acrylic rubber fine particles is
If the thickness exceeds 1 μm, the thickness of the adhesive layer becomes large and curing may become non-uniform, which is not preferable.

The mixing ratio of the urethane-modified epoxy resin and the bisphenol-type epoxy resin is 100
20-80 parts by weight (preferably 30 parts by weight)
To 60 parts by weight), and 10 parts by weight or more of acrylic rubber fine particles are added to 100 parts by weight of the bisphenol-type epoxy resin to obtain the agent A. If the bisphenol-type epoxy resin is less than 20 parts by weight, the cohesive force of the cured product is obtained. Is weak and has adhesiveness, but the adhesive layer may easily collapse,
When the amount exceeds 80 parts by weight, the cohesive strength is improved, but the adhesion is reduced, and the separation at the interface is easily caused.

The agent A of the present invention may further contain a filler, for example, calcium carbonate, talc, etc. for adjusting properties such as viscosity. In addition, additives such as an antifoaming agent, a coupling agent, and a coloring agent can be added as needed.

The polyamidoamine in the agent B of the present invention is a polyaminoamide synthesized from a polymerized fatty acid and polyethyleneamine. The type and the like are not particularly limited if the viscosity, the pot life and the active hydrogen equivalent are taken into consideration according to the working conditions. There is no. Additives such as fillers, non-reactive diluents and accelerators (for example, tertiary amines), defoaming agents, coupling agents, and coloring agents are added to the B agent, as required. You can also.

From the viewpoint of work, it is desirable to mix the above-mentioned agents A and B with the same volume or the same mass, if possible. In addition, it is necessary to consider in order to exert the effect, because the adhesive strength (balance between adhesion and cohesive force) tends to be better when the agent B is added to the agent A in a slightly excessive amount than the equivalent. .

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION

EXAMPLES The present invention will be described in detail below using examples. The two-part adhesives of the present invention were produced at the mixing ratios shown in Table 1. The agent A and the agent B of the two-part adhesive were mixed, and the adhesive strength to the soft polyvinyl chloride resin was measured.

[0019]

[Table 1]

The symbols in the table are as follows. EPU-11: Urethane-modified epoxy resin manufactured by Asahi Denka Kogyo Co., Ltd. Epoxy equivalent: 305, viscosity 20 Pa · s EPR-1309: Rubber-modified epoxy resin manufactured by Asahi Denka Kogyo Co., Ltd. Epoxy equivalent: 300, viscosity 35 Pa · s Epicoat 828: Oiled shell Epoxy general-purpose screw A
Type epoxy resin Epoxy equivalent: 190, viscosity 13 Pa · s BPA-328: Nippon Shokubai Co., Ltd. acrylic rubber fine particles 20
phr-dispersed bis-A type epoxy resin Epoxy equivalent: 230, viscosity 60 Pa · s BPF-307: Acrylic rubber fine particles 20 manufactured by Nippon Shokubai Co., Ltd.
phr-dispersed bis F type epoxy resin Epoxy equivalent: 210, viscosity: 13 Pa · s Sanmide 315: Polyamideamine manufactured by Sanwa Chemical Industry Co., Ltd. Active hydrogen equivalent: 125, viscosity: 10 Pa · s Sanmide 328A: Sanwa Chemical Industry: polyamidoamine active hydrogen Equivalent; 100, viscosity 15 Pa · s K-54: B.I. T. Tertiary amine manufactured by R Japan

1. Tensile shear bond strength A flexible polyvinyl chloride resin having a thickness of 25 × 100 × 2 mm was bonded to the wrap length of 10 mm with the adhesive shown in the above table, and measured at 25 ° C. × 3 days. The surface of the soft polyvinyl chloride resin is methanol-degreased, and the tensile speed is 100 mm / m
in. 2. Peel strength (180 °) A flexible polyvinyl chloride resin having a thickness of 25 × 150 × 1 mm was bonded with the adhesive shown in the above table, and measured at 25 ° C. × 3 days. The surface of the soft polyvinyl chloride resin is methanol-degreased,
Peeling speed 50 mm / min.

The above two items were observed for the adhesive strength and the breaking condition. In addition, the result of the adhesive for vinyl chloride (solvent evaporation type) is also described for reference. Table 2 shows the results.

[0023]

[Table 2]

As a result, Examples 1-4 were satisfactory. In Comparative Example 1, adhesion was poor due to excessive addition of the acrylic rubber fine particle-dispersed epoxy resin, resulting in interfacial peeling and poor strength. Comparative Example 2 had only a urethane-modified epoxy resin and did not contain an acrylic rubber fine particle-dispersed epoxy resin. In Comparative Example 3, a rubber-modified epoxy resin was used instead of the urethane-modified one, but the cured product became hard, the adhesion was not exhibited, and the strength was not obtained because the interface was peeled off. In Comparative Example 4, the bis-A liquid epoxy resin was added instead of the acrylic rubber fine particle dispersed epoxy resin, so that the cured product was hard and the peeling strength was not at all. Although the polyvinyl chloride-based adhesive exhibited some strength, it could not be compared with the examples of the present invention.

The same test was conducted after dipping the tensile shear test pieces of Examples 1 to 4 and the vinyl chloride adhesive in hot water at 40 ° C. for 7 days. Although there was no change, the adhesive strength of the vinyl chloride adhesive was reduced by 50%.

[0026]

As described above, the adhesive of the present invention has excellent adhesiveness to polyvinyl chloride resin, and its industrial value is extremely large. With this adhesive,. Unlike conventional solvent-based adhesives, no solvent is used, and. Since the pot life depends on the polyamide of the B agent, it is not necessary to set an open time, and it is sufficient to bond before the curing time. Since it is liquid until curing, even if it is stuck or bubbles are trapped, bubbles can be expelled by using a roller, etc., so that the adherend is not attacked. Since it is an epoxy resin, it has excellent water resistance after curing. This is extremely useful because it can solve all the problems so far, such as simultaneous filling and sealing with little shrinkage.

Claims (4)

[Claims] 1. An epoxy two-part adhesive comprising the following A agent and B agent. A agent: a 100 parts by weight of a urethane-modified epoxy resin having a viscosity of 50 Pa · s or less, and b one or more liquid epoxy resins 2 selected from bisphenol A type or bisphenol F type epoxy resin 2
A composition comprising, as main components, 0 to 80 parts by weight, and 2 parts by weight or more of acrylic rubber fine particles having an average particle size of 1 μm or less. Agent B: Polyamidoamine 2. The epoxy two-part adhesive according to claim 1, wherein the acrylic rubber fine particles are previously mixed with at least one liquid epoxy resin selected from bisphenol A type or bisphenol F type epoxy resin. 3. The epoxy two-part adhesive according to claim 1, wherein the polyamidoamine is a polyaminoamide synthesized from a polymerized fatty acid and polyethyleneamine. 4. The epoxy two-part adhesive according to claim 1, which is an adhesive for flexible polyvinyl chloride.