JPS6251971B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a fast-curing thermosetting resin composition with excellent adhesive properties and pot life. [Technical background of the invention and its problems] Epoxy-based thermosetting resins are widely used for adhesion of various electronic components and coating agents related to printed circuit boards. Depending on the use, various fillers are added to these resin compositions to improve workability and properties. Such epoxy resin compositions use many types of curing agents, such as polyamide resins, amines, imidazoles, melamines, acid anhydrides, boron trifluoride, and amine complexes. Particularly in the case of one-component compositions, those with a fast curing rate lack storage stability, while those with good stability take a long time to cure, and they also have the drawbacks of poor tensile shear strength when heated. [Object of the Invention] The present invention has been made in order to eliminate the above-mentioned drawbacks, and its object is to provide a fast-curing thermosetting resin composition with excellent adhesiveness, tensile shear strength, and pot life. The purpose is [Summary of the Invention] As a result of extensive research in order to achieve the above-mentioned object, the present invention was made based on the discovery that the resin composition described below can achieve the above-mentioned object. That is, the present invention comprises (a) an epoxy resin, (b) an amide curing agent, (c) a urea curing agent, (d) an organic compound having at least one carboxylic acid group or sulfonic acid group, and ( e) A thermosetting resin composition containing an inorganic filler, wherein the content of (d) an organic compound is 0.1 to 1.0% by weight based on the epoxy resin (a). All kinds of epoxy resins are effective as (a) epoxy resins used in the present invention, but the main ones are epoxy resins having two or more epoxy groups in one molecule. Specifically, bisphenol A type, halogenated bisphenol type, resorcin type, bisphenol F type, tetrahydroxyphenylethane type, novolak type, polyalcohol-polyglycol type, glycerin triether type, polyolefin type, and epoxidized type. Examples include alicyclic types such as soybean oil, dicyclopetadiene dioxide, vinylcyclohexene dioxide, and the like. (b) is a curing agent for the epoxy resin used in the present invention.
Examples of amide curing agents include dicyandiamide, and (c) urea curing agents include 3-
Examples include (3,4-dichlorophenyl)-1,1-dimethylurea. Next, hardening agent (b+c)
The blending amount is 5 parts by weight per 100 parts by weight of epoxy resin.
~30 parts by weight, preferably 7 to 15 parts by weight are suitable. If the amount is less than 5 parts by weight, curing will not be sufficient, and if it exceeds 30 parts by weight, not only will the curing agent be wasted, but it will also cause foaming, etc., which is undesirable. In addition, the blending ratio (b/c) of (b) amide curing agent and (c) urea curing agent is 1 to 5, preferably 1 by weight.
~4 is suitable. If this ratio is less than 1, the stability at room temperature is poor and is not preferred. Also, the ratio is 5
If it exceeds this amount, the curing of the resin composition will be insufficient, which is not preferable. Therefore, it is limited to the above range. (d) The organic compound having at least one carboxylic acid group or sulfonic acid group used in the present invention is
By acidifying the resin composition system, the basicity of the curing agent is neutralized and the pot life of the resin composition is extended. Preferred examples of these carboxylic acids or sulfonic acids include acetic acid and p-toluenesulfonic acid, and the amount thereof is 0.1 to 1.0% by weight based on the epoxy resin. More preferably, 0.2 to 0.5% by weight is suitable. If the amount is less than 0.1% by weight, the pot life cannot be improved, and if it exceeds 1.0% by weight, the curability decreases, which is not preferable. The inorganic filler (e) used in the present invention includes:
When various powders are used and conductivity is required,
Conductive powders such as Ag, Cu, and Ni are used, and for general adhesives and coating materials, examples include calcium carbonate, talc, and silica, the amount of which can be determined arbitrarily depending on the required characteristics. It will be done. In addition to the above-mentioned components, the thermosetting resin composition of the present invention contains various additives such as thixotropic agents, pigments,
Coupling agents, antifoaming agents and leveling agents can be added. The resin composition of the present invention is produced by thoroughly kneading each predetermined component using three rolls or a kneader, and is used as an adhesive or coating agent for various electronic components. Although the resin composition of the present invention can be cured under various curing conditions, curing conditions of 30 minutes at a temperature of 150°C to 1 hour at a temperature of 120°C are preferred. [Effects of the Invention] The thermosetting resin composition of the present invention has excellent adhesion and tensile shear strength even when made into a one-component type, has a very long pot life, and is quick-curing. It is suitable as an adhesive or coating material for various electronic components. [Examples of the Invention] Next, the present invention will be explained by referring to Examples. Example 1 100 parts by weight of Epicoat 828 (epoxy resin trade name from Ciel Chemical Co., Ltd.), 8 parts by weight of dicyandiamide,
3-(3,4-dichloro phenyl)-1,1-
2 parts by weight of dimethylurea, p-toluenesulfonic acid
A one-component thermosetting resin composition was prepared by kneading 0.1 part by weight and 100 parts by weight of calcium carbonate three times using three rolls. The resulting compositions were tested for adhesion, curability, tensile shear and pot life. The results are shown in Table 1. Examples 2 to 4 Resin compositions were prepared using the components shown in Table 1 in the same manner as in Example 1, and the same tests as in Example 1 were conducted on them. The results are shown in Table 1. Ta. Comparative Examples 1 to 3 Resin compositions were produced using the respective components shown in Table 1 in the same manner as in Example 1, and the same tests as in Example 1 were conducted on the resin compositions. Shown in the table. 【table】

Claims (1)

[Scope of Claims] 1 (a) an epoxy resin, (b) an amide curing agent, (c) a urea curing agent, (d) an organic compound having at least one carboxylic acid group or sulfonic acid group, and (e) contains an inorganic filler, and (d) the content of organic compounds is (a)
A thermosetting resin composition characterized in that the proportion is 0.1 to 1.0% by weight based on the epoxy resin. 2. The thermosetting resin composition according to claim 1, wherein the amide curing agent (b) is dicyandiamide. 3 (c) The thermosetting method according to claim 1 or 2, wherein the urea curing agent is 3-(3,4-dichlorophenyl)-1,1-dimethylurea. resin composition. 4. The heat treatment according to any one of claims 1 to 3, characterized in that the amount (b+c) of the curing agent is 5 to 30 parts by weight based on 100 parts by weight of the (a) epoxy resin. Curable resin composition. 5. Claims 1 to 4, characterized in that the blending ratio (b/c) of (b) the amide curing agent and (c) the urea curing agent is 1 to 5 by weight. The thermosetting resin composition according to any one of the above.