JP6540938B2 - Primer composition - Google Patents

Description

The present invention is a non-curable primer composition used in combination with an insulating curable resin composition, and the primer composition contains a curing catalyst of the curable resin composition. (Hereinafter, the term "curable resin composition" refers to an insulating curable resin composition.) When adhering two adherends, a coating of the primer composition on one adherend Then, the adhesion of the other adherend to the coated surface of the primer composition is performed with the curable resin composition. The coating film of the present invention is an invention relating to a primer composition suitable for an adhesive application which does not exhibit conductivity but is capable of securing conductivity and firmly adhering between two adherends.

Patent Document 1 describes the invention of a primer composition for electrostatic coating. Since the coating film itself of the said primer composition has electroconductivity, it is described that it can be used as a base of electrostatic coating. Moreover, although patent document 2 is invention of a primer composition, it is described that the coating film of a primer composition itself is the invention which has electroconductivity like patent document 1, and it can be used for a foundation | substrate. However, in the above two inventions, in order to develop conductivity, it is necessary to add a large amount of a conductive filler, and the adhesion itself is weak.

Japanese Patent Application Laid-Open No. 59-215366 JP-A-2-227482

The conventional primer composition is used as a base of a paint, the coating film of the primer composition itself is conductive, and a large amount of conductive filler is added, so that the adhesion of the primer composition itself is reduced, and used in adhesion applications It was difficult to do.

As a result of intensive studies to achieve the above object, the present inventors have completed the present invention relating to a primer composition suitable for adhesive applications.

The gist of the present invention will now be described. The first embodiment of the present invention is a primer composition containing components (A) to (D) and containing 20 to 3000 parts by mass of component (C) per 100 parts by mass of component (A).
(A) Component: Tackifier and / or epoxy resin solid at 25 ° C. (B) component: curing catalyst (C) component: conductive filler (D) component: solvent dissolving the (A) component

A second embodiment of the present invention is the primer composition according to the first embodiment, wherein the tackifier of the component (A) is a polymer and / or a copolymer of a compound having a terpene skeleton.

A third embodiment of the present invention is the primer composition according to the first embodiment, wherein the epoxy resin solid at 25 ° C. of the component (A) is an epoxy resin having a bisphenol skeleton.

A fourth embodiment of the present invention is the primer composition according to any one of the first to third embodiments, wherein the component (B) is a curing catalyst that promotes anaerobic curing.

The fifth embodiment of the present invention is any one of the first to fourth embodiments, wherein the component (B) is at least one selected from the group consisting of an organic copper complex, an organic iron complex and an amine compound. Primer composition.

A sixth embodiment of the present invention is the primer composition according to any one of the first to fifth embodiments for use in a curable resin composition having an anaerobic curing property.

A seventh embodiment of the present invention is a method of bonding two metallic adherends, wherein one adherend is coated with the primer composition according to any of the first to fifth embodiments. Then, an insulating curable resin composition is applied to the surface of the coating or the other adherend, and the two adherends sandwich the coating and the curable resin composition. It is a method of bonding.

The eighth embodiment of the present invention relates to a method of electrically connecting two metal adherends, wherein the primer composition according to any one of the first to fifth embodiments is applied to one adherend. The coating film is formed by coating, and then the surface of the coating film or the other adherend is coated with an insulating curable resin composition, and the two adherends are coated with the coating film and the curable resin composition. It is the method of electrically connecting by bonding on both sides of.

The ninth embodiment of the present invention is a method of bonding using a curable resin composition having an anaerobic curing property as the curable resin composition according to any of the seventh or eighth embodiments.

The conductivity does not appear in the coating film of the primer composition of the present invention itself, and by combining the coating film of the primer composition and the curable resin composition, the conductivity is ensured between the two adherends. It is a primer composition suitable for adhesive applications that can bond firmly. Here, by securing the conductivity between the adherends, it is possible to perform grounding and static elimination without any problems. In addition, when the primer composition is dropped, the adherend is not always dropped in the horizontal state (0 °), and may be used in the vertical state (90 °), so the present invention relates to the vertical state. The conductive filler does not flow even to the adherend, and the conductive filler can remain at the dropped position.

Fig. 1 shows a member used for conductivity measurement: 1: ITO glass 2: ITO glass conductive surface 0.5 to 1 μm 3: PMMA film spin-coated, radius at center part A 2.5 mm 4: PMMA film was partially removed (1: exposed portion of the ITO glass conductive surface). Fig. 2 shows that 1 mg of the primer composition is applied so as to be uniform on the exposed part of the ITO glass conductive surface, and then left to stand in a 25 ° C. atmosphere for 1 minute; 5: a coating film of the primer composition is formed It is a member of FIG. 3 is the member of FIG. 2 coated with a curable resin composition having anaerobic cureability 6: on the coating film of the primer composition of FIG. 7: The other ITO glass 8: another ITO glass conductive surface is overlapped and fixed with a clip, and it is left as it is in a 25 ° C. atmosphere for 24 hours to cure the curable resin composition. is there.

The details of the invention will now be described. Component (A) which can be used in the present invention is a tackifier and / or an epoxy resin which is solid at 25 ° C. The tackifier is a polymer and / or copolymer of a compound having a terpene skeleton and refers to a polymer containing a terpene such as a hydrogenated terpene resin, a terpene phenol copolymer, and an aromatic terpene polymer. Also, one type may be used alone, or a plurality of types may be mixed and used. Examples thereof include Clearon P105, YS Polystar T80, and YS Resin TO 85 manufactured by Yasuhara Chemical Co., Ltd., but are not limited thereto.

The epoxy resin solid at 25 ° C. is an epoxy resin having a bisphenol skeleton and refers to a polymer or copolymer of bisphenol A epoxy resin or bisphenol F epoxy resin, or phenoxy resin. Specific examples thereof include jER 1002 manufactured by Mitsubishi Chemical Co., Ltd., but not limited thereto.

The component (B) that can be used in the present invention is a curing catalyst, and the curing catalyst may have the function of promoting the curability of the curable resin composition used in combination with the primer composition.

In particular, for a curable resin composition having anaerobic curing properties, organic copper complexes, organic iron complexes, amine compounds and the like that promote anaerobic curing properties may be mentioned. Although a naphthate copper, copper 2-ethylhexanoate etc. are mentioned as a specific example of (B) component in this case, It is not limited to these. The component (B) can be used either solid or liquid as long as it can be dissolved in the component (D) described later. The component (B) may be used alone or in combination of two or more.

In the present invention, the component (B) is preferably contained in an amount of 1 to 200 parts by mass with respect to 100 parts by mass of the component (A). When the component (B) is added in an amount of 1 part by mass or more, the curable resin composition used in combination with the primer composition can be rapidly cured. On the other hand, when 200 parts by mass or less of the component (B) is added, the component (B) can be dissolved or compatible with the component (D) described later.

The component (C) that can be used in the present invention is a conductive filler. As the conductive filler, the outermost surface may be gold, silver, nickel or the like, and the average particle diameter of the filler is about the clearance between adherends, and the shape may be spherical, flake, needle or the like. Can. Particularly preferred is a so-called plated filler in which the core is coated with a spherical organic material with a metal. The specific gravity is also low and it tends to be difficult to settle. Examples of the plating filler include, but are not limited to, Bright 20 GNR 4.6-EH manufactured by Nippon Chemical Industry Co., Ltd. as a gold-nickel plating filler.

As a composition which added the conductive filler which is the (C) ingredient to a curable resin composition, it is known as a conductive resin composition. However, since a metal ion becomes a curing catalyst to a curable resin composition having an anaerobic curing property by containing saccharin, a conductive filler can not be added. If it is temporarily added, the curable resin composition will gel or thicken due to the metal ion. When used in combination with a curable resin composition having an anaerobic curing property and the primer composition of the present invention, the storage stability of the curable resin composition can be secured, and the cured product can exhibit conductivity.

It is preferable that (C) component is 20-3000 mass parts with respect to 100 mass parts of (A) component. When 20 parts by mass or more of the component (C) is added, conductivity is exhibited by using it in combination with the curable resin composition. On the other hand, when 3000 parts by mass or less is added, the leveling property is maintained and a uniform coating film is formed.

Component (D) that can be used in the present invention is a solvent that dissolves component (A). In particular, solvents having low polarity and high volatility are preferable, and specifically, hexane, toluene and the like can be mentioned. In order to adjust the leveling property and viscosity of a primer composition, (D) component can be added suitably.

The component (D) is preferably contained in an amount of 100 to 50000 parts by mass with respect to 100 parts by mass of the component (A). When 100 parts by mass or more of the component (D) is added, the leveling property is maintained, and a uniform coating film is formed. On the other hand, when the component (D) is added in an amount of 50000 parts by mass or less, the conductivity is stably expressed by using it in combination with the curable resin composition.

In the primer composition of the present invention, pigments, colorants such as dyes, metal powders, inorganic fillers such as calcium carbonate, talc, silica, alumina, aluminum hydroxide and the like, flame retardants, as long as the characteristics of the present invention are not impaired. Additives such as organic fillers, plasticizers, antioxidants, antifoaming agents, coupling agents, leveling agents, rheology control agents and the like may be blended in appropriate amounts. By these additions, a composition excellent in resin strength, workability, storage stability and the like and a cured product thereof can be obtained.

The primer composition of the present invention contains a component that accelerates the curing of the curable resin composition, and the primer composition is applied in advance and dried to form a coating film, and then the curable resin composition is applied to the composition. Contact with the membrane promotes the cure of the contact portion. In particular, the present invention is preferably used in combination with a curable resin composition having an anaerobic curing property that cures in a short time under a 25 ° C. atmosphere. Specific examples of the curable resin composition having anaerobic curing properties include ThreeBond 1354 manufactured by Three Bond Fine Chemical Co., Ltd., and the like, but are not limited thereto.

As a method of using the primer composition, particularly when bonding two adherends, after forming a coating film of the primer composition on one adherend, the other adherend and the coated surface of the primer composition Adhesion is carried out with a curable resin composition. At that time, as adhesion form, fitting adhesion and surface adhesion are preferable, it is better that the clearance between the two adherends is narrow, and 5 μm to 100 μm is preferable as the clearance.

EXAMPLES The present invention will next be described in more detail by way of examples, which should not be construed as limiting the invention thereto. (Hereafter, the primer composition is simply referred to as a composition.)

The following ingredients were prepared to prepare the composition.
(A) Component: Tackifier and / or epoxy resin solid at 25 ° C · hydrogenated terpene resin having a softening point of 152 ° C (CLEARON P105, manufactured by Yasuhara Chemical Co., Ltd.)
· Terpene phenol copolymer with a softening point of 80 ° C (YS Polystar T80 made by Yasuhara Chemical Co., Ltd.)
・ Aromatic terpene polymer with a softening point of 85 ° C (YS resin TO 85 manufactured by Yasuhara Chemical Co., Ltd.)
Solid epoxy resin with a softening point of 78 ° C (jER1002 manufactured by Mitsubishi Chemical Corporation)
(A ') Component: Other than the (A) component ・ Hydroxy-terminated liquid polyisoprene (Poly ip manufactured by Idemitsu Kosan Co., Ltd.)
・ Polyvinyl butyral resin (S-REC BL-1 manufactured by Sekisui Chemical Co., Ltd.)
Component (B): Curing catalyst, naphthate copper (reagent)
-Copper 2-ethylhexanoate (reagent)
Component (C): Conductive filler / coated metal is a gold-nickel plated filler (Bright 20 GNR 4.6-EH manufactured by Nippon Chemical Industrial Co., Ltd.)
Component (D): Solvent that dissolves component (A), hexane (reagent)
・ Toluene (reagent)
Other solvents, ethanol (reagent)
・ Acetone (reagent)

[Reference 1 to 16]
In order to prepare references 1 to 16, after the component (D) is weighed in a container, the component (A) or the component (A ′) is weighed and charged in the container and stirred for 1 hour until it is dissolved. The detailed preparation amounts are shown in Table 1 and all numerical values are expressed in parts by mass.

[Solubility check]
5 g of the composition is weighed into a glass tube, and the state of dissolution is visually confirmed to make it "soluble". The "solubility" is preferably "o".
Evaluation criteria O: Transparent, stable even when left △: Transparent, but changed when left: Poor: White turbidity or undissolved matter

[Coating film status check]
The composition was applied on a glass plate to form a 3 μm thick coating and dried at 25 ° C. for 24 hours. Based on the following evaluation criteria, the presence or absence of tack is confirmed by finger touch on the surface of the coated film, and the coated film state is obtained. From the viewpoint of retention of the conductive filler, the “coating state” is preferably “o”. When "solubility" is "x", a coating-film state confirmation is not performed but it describes with "not confirmable."
Evaluation criteria ○: no tack ×: tack is present

In Table 1, the solubility of (A) component or (A ') component and the coating-film state after (D) component drying were confirmed. In the references 1 and 3, the combination of the hydrogenated terpene resin and hexane or toluene, and in the references 15 and 16, the combination of the solid epoxy resin and toluene or acetone showed good results in the solubility and the state of the coating.

[Examples 1 to 10, Comparative Examples 1 to 3]
In order to prepare the composition, component (D) is weighed in a container, and then component (A) or component (A ′) is weighed and charged in the container and stirred for 1 hour until dissolution. If the solvent evaporates, add volatile matter. Thereafter, components (B) and (C) are added and stirred for 30 minutes. The detailed preparation amounts are in accordance with Table 2, and all numerical values are expressed in parts by mass.

With respect to Examples 1 to 10 and Comparative Examples 1 to 3, solubility check, filler holding state check, fitting adhesion measurement, and conductivity measurement were performed, and the results are summarized in Table 3.

[Filler holding status check]
0.1 g of the composition is dropped on a glass plate, and the glass plate is inclined upright (90 °). In this state, it is left at 25 ° C. for 1 hour. The residual state of the conductive filler is visually confirmed by a microscope according to the following evaluation criteria at the place where the solution was dropped and the place where it flowed most to make it a “filler-held state”. When the primer composition is dropped, the adherend is not always dropped in the horizontal state (0 °) but may be used in the vertical state (90 °), so the filler retention state is “o”. Is preferred.
Evaluation criteria ○: There is no bias in the presence of the conductive filler in two places ×: There is a bias in the presence of the conductive filler in two places

[Metering adhesion measurement]
ThreeBond 1354 manufactured by Three Bond Fine Chemical Co., Ltd. was used as a curable resin composition having an anaerobic curing property, and it was combined with the primer composition to measure the adhesive strength by fitting. The composition is uniformly applied to SPCC pins of about 6 mm in diameter and left at 25 ° C. for 1 hour. After that, ThreeBond 1354 is applied to the inside of an SPCC collar with an inner diameter of 6 mm and a length of 15 mm, the pin is inserted, and left at 25 ° C. for 10 minutes. After that, the maximum strength is measured with a strength measuring machine, and the "mating adhesion (MPa)" is obtained. The fitting adhesive force is preferably 10 MPa or more, and if 10 MPa or more, it is considered that the promoting effect as a primer is exhibited. On the other hand, when using only ThreeBond 1354 without using the composition, the fitting adhesion when left at 25 ° C. for 10 minutes was 26 MPa.

[Conductive measurement]
As shown in Fig. 1, 1: ITO glass 2: ITO glass conductive surface 3: 0.5 mm thick 3: PMMA film spin-coated, central part radius 2.5 mm 4: PMMA film one Create the excluded holes of the part (1: exposed part of the ITO glass conductive surface). As shown in FIG. 2, after 1 mg of the composition is applied so as to be uniform on the exposed portion of the ITO glass conductive surface, it is left to stand in a 25 ° C. atmosphere for 1 minute. Since a coating film in which the solid content of the composition remains is formed, as shown in FIG. 3, it has an anaerobic curing property 6: 1 mg of ThreeBond 1354 is applied as a curable resin composition, as shown in FIG. 7: The other 8 ITO glass conductive surface of the other ITO glass is overlapped and fixed with a clip. The curable resin composition is cured by standing for 24 hours in a 25 ° C. atmosphere. Place the tester's electrode on the ITO glass conductive surface and measure the resistance value. The measurement is performed at n = 5, and the average value is taken as "conductivity (Ω)". When the resistance value is high enough that the resistance value can not be measured by a tester, it is described as "OL". The "conductivity" is preferably 500 ohms or less, and if it is 500 ohms or less, ground removal and static elimination can be performed without problems.

In Examples 1 to 3, the type of tackifier is changed for verification, and the filler retention state is good. Moreover, in Examples 4, 5, and 9, the kind and the addition amount of the (B) component are changed, but the fitting adhesive force is 10 MPa or more. Although the elastomer of the component (A ') is added in Example 6, the same characteristics as Example 1 are exhibited. On the other hand, Comparative Example 1 does not contain the component (A), the filler retention state is poor, and the conductive filler is biased. The conductivity of Comparative Example 2 is unstable because the amount of the component (C) is less than 20 parts by mass with respect to 100 parts by mass of the component (A). In Comparative Example 3, the filler retention state is poor.

Although it is necessary to heat the reaction curable conductive adhesive in the range of 60 to 200 ° C., by combining the primer composition of the present invention and the nonconductive composition, the conductivity is easily secured between adherends. can do. In the electric and electronic fields, it is necessary to remove the earth and to eliminate static electricity, and the heat resistance of the adherend sometimes prevents heating, so the scope of using the present invention is expanded.

1: ITO glass 2: ITO glass conductive surface 3: PMMA film 4: Hole from which part of the PMMA film has been eliminated (1: exposed part of ITO glass conductive surface)
5: Coating of primer composition 6: Curable resin composition 7: Another ITO glass 8: Another ITO glass conductive surface

Claims (9)

The primer composition which contains (A)-(D) component, and (C) component contains 20-3000 mass parts with respect to 100 mass parts of (A) components.
Component (A): Tackifier and / or epoxy resin solid at 25 ° C. (B): organic copper complex (C): conductive filler (D): solvent for dissolving component (A) The primer composition according to claim 1, wherein the tackifier of the component (A) is a polymer and / or a copolymer of a compound having a terpene skeleton. The primer composition according to claim 1, wherein the epoxy resin solid at 25 ° C of the component (A) is an epoxy resin having a bisphenol skeleton. The primer composition according to any one of claims 1 to 3, wherein the component (B) is at least one selected from the group consisting of naphthate copper and copper 2-ethylhexanoate. The primer composition according to any one of claims 1 to 4, wherein the component (B) is 1 to 200 parts by mass with respect to the component (A). The primer composition according to any one of claims 1 to 5, which is used for a curable resin composition having an anaerobic curing property. In the method for bonding two metallic adherends, after forming a coating on one adherend with the primer composition according to any one of claims 1 to 6, the surface of the coating or the other A method in which an insulating curable resin composition is applied to an adherend, and the two adherends adhere to each other across the coating film and the curable resin composition. In a method of electrically connecting two metallic adherends, after forming a coating on one adherend with the primer composition according to any one of claims 1 to 6, the surface of the coated film Or a method in which an insulating curable resin composition is applied to the other adherend, and two adherends are electrically connected by bonding the coating film and the curable resin composition between them. . 9. A method of bonding using a curable resin composition having an adverse curing property as the insulating curable resin composition according to any one of claims 7 and 8.