JP3334160B2 - Microcapsule type adhesive composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to, for example, screws, bolts,
The microcapsules are used by being applied to the screwing surface (thread) of a screwing member such as a nut. When the screwing member is tightened, the microcapsules are crushed, and the contained adhesive reacts and hardens to loosen the screwing member. The present invention relates to a microcapsule-type adhesive composition capable of achieving sealing and sealing, and in particular, functions as a binder by fixing microcapsules to a screw-in member, and also functions as a curing agent to impart strong adhesive force. Further, the present invention relates to a microcapsule-type adhesive composition capable of firmly preventing loosening and sealing of a screw member.

[0002]

2. Description of the Related Art A microcapsule-type adhesive composition which is applied to a screwing surface (thread) of a screwing member such as a screw, a bolt, a nut and the like to be used for the purpose of preventing the screwing member from loosening and sealing. 2. Description of the Related Art Conventionally, a composition containing microcapsules containing an adhesive and an emulsifying resin as a binder has been known. (Japanese Patent Application Laid-Open No. Sho 53-11883, which discloses an aqueous emulsion of a polymer as a binder, and Japanese Patent Application Laid-Open No.
308876)

[0003]

However, in the above-mentioned known technology, the emulsion or slurry used as a binder does not cause a crosslinking reaction with the adhesive composition encapsulated in microcapsules. This means that in the adhesive composition cured by tightening the screw member, the polymer component of the emulsion or slurry acts as a plasticizer, so that the adhesive strength is reduced, and further, the chemical resistance and heat resistance are reduced. Will come.

Accordingly, an object of the present invention is to use an adduct compound with a curing agent as a binder for fixing the microcapsules on the screwing surface, thereby fixing the microcapsules to the screwing member and exhibiting the function as a binder. Since it itself acts as a curing agent for the epoxy compound encapsulated in the capsule and crosslinks, it exhibits a strong adhesive force, whereby the screwing member can be firmly prevented from loosening and sealing, and is in the above-mentioned known art. An object of the present invention is to provide a microcapsule type adhesive composition which has improved disadvantages.

[0005]

Means for Solving the Problems The above-mentioned object of the present invention is to provide the following components (a), (b) and (c) with water or
Is mixed and emulsified and dispersed in a mixed solvent composed of water and alcohol , and the above (b) and (c) are mixed in the solvent.
Can be added to form an adduct compound, which can be achieved by preventing the screwing member from loosening or being applied to the screwing surface of the screwing member, or by using a microcapsule-type adhesive composition for sealing. ( A ) Microcapsules encapsulating an epoxy compound (b) Bisphenol A type epoxy resin with polyhydric alcohol
(C) a self-emulsifying epoxy resin obtained by reacting
1.5 to 20 times the amount of epoxy resin curing agent

[0006]

Hereinafter, the present invention will be described in detail.

The above-mentioned microcapsules according to the present invention have urea-formalin resin, melamine-
It is constituted by using a resin that does not easily swell in water, such as formalin resin, and using any known epoxy compound as an encapsulated epoxy resin.

The (b) self-emulsifying epoxy resin used in the present invention is an epoxy compound obtained by reacting a bisphenol A type epoxy resin with a polyhydric alcohol.
Specifically, a compound obtained by adding a bisphenol A type epoxy resin to a polyhydric alcohol or a compound obtained by reacting a bisphenol A type epoxy, bisphenol A and isophorone diisocyanate with this compound at a specific molar ratio are further added. It is a compound obtained by the reaction .

[0009] Specific examples of the polyhydric alcohols mentioned above,
Ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, polyoxypropylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 1,5-pentanediol, 1,2,6-hexanetriol , Glycerol, bis- (4-hydroxycyclohexyl)-
2,2-propane and the like.

The dispersion solvent in the present invention may be either water alone or a mixture of water and an organic solvent such as alcohols. Further, in order to promote the dispersion of the self-emulsifying epoxy resin in water, a surfactant is used. The agent may be added up to 10% by weight based on the self-emulsifying epoxy resin.

As the epoxy resin curing agent (c) used in the present invention, specifically, polyamines such as polyalkyleneamines, alicyclic amines and aromatic amines, Mannich bases, polyepoxides and polyamines And a basic curing agent such as an adduct compound, which is an addition product of an acid, an acidic curing agent such as a polycarboxylic acid, an acid anhydride and a phenol, and a condensation product of an aldehyde.

The polyalkyleneamines include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, 2,2,4- or 2,4,4-trimethylhexamethylenediamine, bis- (3-aminopropyl) methylamine, Examples thereof include 1,4-bis- (3-aminopropyl) piperazine and N, N-bis- (3-aminopropyl) ethylenediamine.

The alicyclic amines include 1,2- or 1,3-diaminocyclohexane, 1,4-diamino-
3,6-diethylhexane, 1,2-diamino-4-ethylcyclohexane, 1,4-diamino-3,6-diethylcyclohexane, 1-cyclohexyl-3,4-diaminocyclohexane, isophoronediamine, 4,4 ′
-Diaminodicyclohexylmethane, 4,4'-diaminodicyclohexylpropane, 2,2'-bis- (4aminocyclohexyl) propane, 3,3'-dimethyl-
4,4'-diaminodicyclohexylmethane, 3-amino-1-cyclohexaneaminopropane, 1,3- or 1,4-bis- (aminomethyl) -cyclohexane and the like.

The araliphatic amines include xylene diamine or hydrogenated products thereof.

Examples of the Mannich base include condensation products obtained by reacting aldehydes and phenols with polyamines.

Examples of the addition products of polyepoxide and polyamine include polyepoxides such as terminal epoxide compounds, polyglycidyl ethers and polyglycidyl esters, ethylenediamine, hexamethylenediamine, and methylenediamine.
An adduct compound which is an addition reaction product with a diamine such as xylene diamine or a polyamidoamine.

Examples of the polycarboxylic acid include cyclopentanecarboxylic acid, butanetetracarboxylic acid, cyclobutanetetracarboxylic acid, aconitic acid , citric acid, and acid esters having a free COOH of polyhydric alcohol and polycarboxylic acid.

Examples of the phenols include resols, formaldehyde-phenol carboxylic acid resin, and etherified phenol resin resol.

Other acidic curing agents include p-toluenesulfonic acid, cyclohexanesulfamic acid, acidic butyl phosphate and the like, and can be used in combination with an amine curing agent.

Examples of the aldehyde condensation products include amine aldehyde resins containing amines and aldehydes, melamine resins containing melamine and aldehydes, urea resins containing urea and aldehydes, and acetoguanamine resins containing acetoguanamine and aldehydes. There is.

The above-mentioned epoxy resin curing agent is added in an excess amount of 1.5 to 20 times the epoxy equivalent of the self-emulsifying epoxy resin, and causes an addition reaction to form an adduct compound film on the screwed surface. I do. The coating of the adduct compound functions to fix the microcapsules to the screw member. Further, it acts as a curing agent for the encapsulated epoxy compound when the microcapsules are crushed by tightening the screw member.

In the present invention, a filler, an antifreezing agent, an adhesion-imparting agent, a surfactant and the like may be conveniently added in addition to the above-mentioned components.

[0023]

In the composition according to the present invention, the adduct compound forms a film on the screwing surface of the screwing member, firmly fixes the microcapsules to the screwing member, and exhibits an action as a binder. When the microcapsules are crushed by tightening, the curing agent in the adduct compound cures the epoxy resin encapsulated in the microcapsules, and also acts as a curing agent, and has both sides of a binder and a curing agent. Agent composition.

[0024]

EXAMPLES Examples 1 to 10 and Comparative Examples 1 to 3 shown in Table 1 were prepared, and each sample was applied to an M10 bolt, tightened at 300 kgf-cm, and cured under specified conditions. Was.

[0025]

[Table 1]

The components shown in Table 1 were as follows.

A (self-emulsifying epoxy resin) A bisphenol A type epoxy resin having an epoxy equivalent of 185 was added to polyethylene glycol having an average molecular weight of 2,000, and 50 g of a self-emulsifying epoxy resin adjusted to an epoxy equivalent of 1300 was added to 5 g of methoxypropane. 50% by weight obtained by dispersing while diluting with 45 g of deionized water
Self-emulsifying aqueous epoxy dispersion having a solid content of (Epoxy equivalent 2600)

B (Self-emulsifying epoxy resin) A bisphenol A type epoxy resin having an epoxy equivalent of 185 was added to polyethylene glycol having an average molecular weight of 4000, and 50 g of a self-emulsifying epoxy resin adjusted to an epoxy equivalent of 3000 was added to 5 g of methoxypropane. 50% by weight obtained by dispersing while diluting with 45 g of deionized water
Self-emulsifying epoxy water dispersion with a solids content of. (Epoxy equivalent 6000)

C (self-emulsifying epoxy resin) A self-emulsifying epoxy resin adjusted to an epoxy equivalent of 1300 by adding a bisphenol A type epoxy resin having an epoxy equivalent of 185 to polyethylene glycol having an average molecular weight of 2,000, and an epoxy equivalent of 185 bisphenol A type epoxy / bisphenol a / isophorone diisocyanate = 1 mol / 1 mol / 1 mol of the reaction was further reaction
To 50 g of the self-emulsifying epoxy resin adjusted to an epoxy equivalent of 800, 10 g of methoxypropanol and 40 g of deionized water were added and diluted and dispersed to obtain a self-emulsifying epoxy water having a solid content of 50% by weight. Dispersion. (Epoxy equivalent 1600)

D (curing agent) 1,3-di-4-piperidylpropane active hydrogen equivalent 105

E (curing agent) 1,3-di-4-piperidylpropane / phenylglycidyl ether = 1 mol: 1 mol adduct curing agent active hydrogen equivalent 361

F (curing agent) Commercial aqueous curing agent Becco Box EH623
(Hoechst synthesis) Active hydrogen equivalent 160

Epoxy-encapsulated microcapsules Epicoat 828 (oiled shell: epoxy equivalent: 18)
5) Inclusion capsule (20-70μ) Inclusion rate 70% by weight Wall material: urea formalin

Test Method Test piece: A sample (adhesive composition) of each of Examples and Comparative Examples is applied to a bolt having a diameter of 10 mm and air-dried to prepare a test piece.

Return torque: A test piece is fastened to a female screw having an inner diameter of 10 mm with a torque of 300 kgf-cm.
Let stand for 72 hours to cure the microcapsule adhesive. The torque when loosening the test piece was measured.

Tightening resistance: Test piece with an inner diameter of 10 m
The torque at the time of starting tightening after assembling with the female screw was measured.

Liquid stability: Samples (adhesive compositions) of Examples and Comparative Examples were placed in a glass test tube, allowed to stand at room temperature, and the number of days of thickening and gelation was measured.

In the above test, in Comparative Example 1, since the equivalent ratio of the self-emulsifying epoxy resin and the curing agent was matched, the polymer was polymerized in water and the liquid stability could not be obtained.

In contrast, in Examples 1 to 10, even when polymerized in water, the cured product exists as an adduct cured product, so that further polymerization does not proceed and the stability is secured.

Further, in Comparative Examples 1 to 3, the tightening resistance was increased because the binder was too hard, and the practicality was poor. However, in Examples 1 to 10 according to the present invention, since the cured product was present as an adduct, crosslinking was not achieved. As the film does not proceed, the film becomes brittle, so that the tightening resistance is reduced. However, it was confirmed that the microcapsules were securely fixed to the screw member.

Further, in Examples 1 to 10 of the present invention, the return torque values are all larger than those in Comparative Examples 1 to 3, and the loosening and sealing of the screwed member are firmly achieved.

[0042]

As described above, the adhesive composition of the present invention reliably functions as a binder by firmly fixing the microcapsules to the screw member, and the curing agent for the epoxy compound in which the binder itself is encapsulated in the capsule. Since it acts as a crosslink, it exhibits a strong adhesive force, and can firmly prevent loosening and sealing of the screwed member.

Further, since the adduct compound of the self-emulsifying epoxy resin according to the present invention is an aqueous dispersion, when the adhesive composition of the present invention is applied to the surface to be screwed, the vapor of the organic solvent is reduced as in the prior art. It does not occur and is excellent in work hygiene.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-208387 (JP, A) JP-A-3-20383 (JP, A) JP-A-5-295339 (JP, A) JP-A-5-295339 17723 (JP, A) JP-A-5-255654 (JP, A) JP-A-5-65391 (JP, A) JP-A-3-1955791 (JP, A) JP-A-2-11619 (JP, A) JP-A-2-36289 (JP, A) Japanese Patent Publication No. 54-1737 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09J 4/00-201/10 F16B 39/02

Claims (2)

(57) [Claims] 1. The following components (a), (b) and (c)
Is mixed with water or a mixed solvent of water and alcohol to emulsify and disperse, and in the solvent,
A microcapsule-type adhesive composition for preventing or loosening a screwed member used by being applied to a screwing surface of a screwed member, wherein the adhesive compound is formed by an addition reaction of (c) and (c). (A) a microcapsule containing an epoxy compound; (b) a self-emulsifying epoxy resin obtained by reacting a polyhydric alcohol with a bisphenol A type epoxy resin; and (c) an epoxy resin of the (b) self-emulsifying epoxy resin.
1.5 to 20 times the amount of epoxy resin curing agent 2. The microcapsule adhesive composition according to claim 1, wherein the polyhydric alcohol in the (b) self-emulsifying epoxy resin is polyethylene glycol.