JPH0826289B2 - Primer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a primer used for bonding a nonpolar or highly crystallized resin with a cyanoacrylate adhesive.

(Prior Art) Non-polar or highly crystallized resins such as polyolefin, polyethylene terephthalate, polyacetal and nylon, fluorine resin, and soft PVC film containing a large amount of plasticizer are lightweight and have excellent physical properties and rustlessness. To have
It is extremely useful as a sheet or molded product used for automobiles and electric devices, and its many uses can be seen. However, since these molded products and the like are non-polar or highly crystallized resins as described above, they are fixed to other members,
There is a problem that it is difficult to adhere or paint when the surface is painted and used.

Therefore, conventionally, some methods have been proposed for improving the adhesiveness and the like. For example; a) A method of partially oxidizing and activating the surface of a difficult-to-bond material such as polyethylene or polypropylene by flame treatment, corona discharge, radiation treatment, etc. Method by treatment of a primer obtained by dissolving polyethylene chloride, polypropylene chloride, or fatty acid-modified alkyd resin used in order to improve the adhesiveness in an organic solvent (used to improve the adhesiveness of an overcoat on an adherend, paint, etc. Undercoat) (JP-A-52-98062)
(See Japanese Unexamined Patent Publication No. 56-141328 and Japanese Unexamined Patent Publication No. 57-119929) (C) Primer treatment of an organometallic compound used in connection with an adhesive containing α-cyanoacrylate as a main component ( JP-A-60-203684) is known).

(Problems to be Solved by the Invention) By the way, in the case of using the method of subjecting the hard-to-bond material to a flame treatment or the like to partially oxidize and activate the surface of the material as in the method (a) above. Is a special processing device,
A treatment method is required, and a non-sticking object having a complicated shape cannot be uniformly treated, so that the work is complicated and the running cost is high and the economy is poor.

Further, (B) is a primer using chlorinated polyethylene, etc., even if the adhesion to the polyolefin is good,
It has been pointed out that even if the adhesion to the top coating is poor, or even if the adhesion to the top coating and the polyolefin is good, the film-to-film adhesion is reduced by repeated cooling and heating cycles. (See the description in JP-A-58-8734).

Further, the primer (c) has adhesiveness to polypropylene molded products and the like to the extent of material destruction, but has insufficient adhesive strength to polyethylene molded products and the like and does not have sufficient strength to destroy materials. The water resistance and moisture resistance of the joint formed between the adherends are being improved, but they are still insufficient, and sufficient adhesive strength cannot be sufficiently maintained.

(Means for Solving Problems) In order to solve the above problems, the present invention provides (a) a [(C _n H _{2n + 1} ) O] group (in the formula, n is an integer of 1 to 6). 1) or more and a first component of a silane compound having either an amino group or a mercapto group, and (b) a compound having an active hydrogen group consisting of a mercaptan, an alcohol, a carboxylic acid or an amine. A mixture with a second component, when the first component is a silane compound having an amino group, the second component is a compound having an active hydrogen group of any of mercaptan, alcohol and carboxylic acid, In the case where one component is a silane compound having a mercapto group, a primer for a cyanoacrylate adhesive in which the second component is a compound having an active hydrogen group of any one of alcohol, carboxylic acid and amine was used.

This primer is a reactive adhesive mainly composed of silicone resin, acrylic resin, epoxy resin, synthetic rubber,
It is used for adhesion to non-polar or highly crystallized resin using a non-reactive adhesive composed mainly of polyurethane etc., or for coating, printing, etc., and especially α-cyanoacrylate is non-polar or high It is also extremely effective when used as an adhesion aid for printing inks or as an adhesion aid for crystallization resins.

Here, [(CnH _{2n + 1} O] as the above-mentioned first component
The silane compound having one or more groups (wherein n is an integer of 1 to 6) has one or more methoxy groups or ethoxy groups, and has an amino group or a mercapto group in its molecule. As specific examples, aminomethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 2-aminoethylaminomethyltrimethoxysilane, 3-aminopropyldimethylethoxysilane, 3-
Aminopropyldiethoxymethylsilane, 3- (2-aminoethylaminopropyl) dimethoxymethylsilane,
3- (2-aminoethylaminopropyl) trimethoxysilane, 2- (2-aminoethylthioethyl) diethoxymethylsilane, dimethoxymethyl-2-pyridinoethylsilane, 3-morpholinopropyltrimethoxysilane, dimethoxymethyl -3-Piperazinopropylsilane, 3-Piperazinopropyltrimethoxysilane, N-
(3-triethoxysilylpropyl) urea, 3-aminopropyltriethoxysilane, 3-dimethylaminopropyldiethoxymethylsilane,
2- (2-aminoethylthioethyl) triethoxysilane, 3- [2- (2-aminoethylaminoethylamino) propyl] trimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 2-aminoethylaminomethylbenzyl Roxydimethylsilane, N- (3-diethoxymethylsilylpropyl) succinimide, 3-cyclohexylaminopropyltrimethoxysilane, 3-
Cyclohexylaminopropyltriethoxysilane, benzylidene-3-ethoxydimethylsilylpropylamine, dimethoxyphenyl-2-piperidinoethoxysilane, N- (3-triethoxysilylpropyl) -p-nitrobenzamide, 3- (vinylbenzylamino) Propyl) triethoxysilane, dimethyloctadecyl-3-
Trimethoxyl silylpropyl ammonium chloride etc. are mentioned. These silane compounds are used alone or in a mixture of two or more. In this case, in the above-mentioned silane compound, it is preferable that a primary amine is used as the amino group because the number of active hydrogen groups increases and the adhesive strength between adherends increases.

When any one of mercaptan, alcohol and carboxylic acid is used as the active hydrogen compound of the following second component, a silane compound having an amino group is used as the first component. When any one of alcohol, carboxylic acid, and amine is used as the active hydrogen compound of the second component, a silane compound having a mercapto group is used as the first component.

The compounding ratio of the above-mentioned silane compound is usually 0.0005 to 10 parts by weight, preferably 0.005 to 10 parts by weight. In this case, if the blending ratio of the silane compound is 0.0005 parts by weight or less, it becomes difficult to obtain sufficient adhesive strength, and if it is 10 parts by weight or more, the strength of the adhesive layer with respect to the adherend may decrease.

Further, in active hydrogen of the second component, it may be possible to mix the amine or mercaptan as a silane compound having an amino group or a mercapto group of the first component, not as the second component, and in this case, the first component The compounding amount of can be a combination of the amount of the first component and the amount of the following second component in the range defined above.

Next, the active hydrogen compound as the second component is used alone or in a mixed system in which two or more kinds of the following mercaptans, alcohols, carboxylic acids and amines are used in combination.

Examples of mercaptans include mercaptoacetic acid, mercaptosuccinic acid, mercaptomalic acid, 3-mercaptopropionic acid, thioglycerol, polyethylene glycol dimercaptoacetate, 2,2′-dimethylmercaptodiethyl ether, thioglycerol, polyethylene glycol di-3- Mercaptopropionate, polyethylene glycol dimercaptoacetate, dodecyl thioglycolate, methyl thioglycolate, 2-mercaptobenzothiazole, diisopropylbenzothiazyl-2-sulfonamide, 2-thio-hydantoin,
2-mercapto-6-nitrobenzothiazole, thiophenol, 2-benzimidazole thiol, 3,3-thiopropionic acid, sodium thioglycolate, polyethylene dimercaptoacetate, isodecyl thioglycolate, mercaptosilane, dodecanethiol, mercapto Examples thereof include methyltrimethoxysilane, mercaptomethyltrimethylsilane, dimethoxy-3-mercaptopropylmethylsilane, 3-mercaptopropyltrimethoxysilane, and 1,3-bis (3-mercaptopropyl) tetramethyldisiloxane.

When a silane compound having a mercapto group is used as the active hydrogen compound, a silane compound having no mercapto group is used as the first component.

Examples of alcohols include methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, pentyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol, decyl alcohol, dodecyl alcohol, tetradecyl alcohol, hexadecyl alcohol, octadecyl alcohol, isopropyl alcohol, isobutyl. Alcohol, sec-butyl alcohol, tert-butyl alcohol, isopentyl alcohol, 2-methyl-1-butanol, tert-pentyl alcohol, cyclopentanol, cyclohexanol, allyl alcohol, crotyl alcohol, cinnamyl alcohol, ethylene glycol, Propylene alcohol, 1,3-propanediol, glycerin, pentaerythritol, etc. .

Examples of the carboxylic acid include oxalic acid, malonic acid, succinic acid, tartaric acid, glutaric acid, adipic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, Caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linoleic acid, cyclohexanecarboxylic acid, phenylacetic acid, benzoic acid, toluic acid, chlorobenzoic acid, bromobenzoic acid, nitrobenzoic acid Acid, phthalic acid, isophthalic acid, salicylic acid, anthranilic acid and the like can be mentioned.

Examples of the amine include 3-aminopropyltriethoxysilane, 3-dimethylaminopropyldiethoxymethylsilane, 2- (2-aminoethylthioethyl) triethoxysilane, and 3- [2- (2-aminoethylaminoethylamino). ) Propyl] trimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 2-aminoethylaminomethylbenzyloxydimethylsilane, N-
(3-diethoxymethylsilylpropyl) succinimide, 3-cyclohexylaminopropyltrimethoxysilane, 3-cyclohexylaminopropyltriethoxysilane, benzylidene-3-ethoxydimethylsilylpropylamine, alanine, arginine, asparagine,
Examples include aspartic acid, cysteine, cystine, glutamic acid, glycine, histidine, hydroxylysine, hydroxyproline, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, thioroxine, tryptophan, tyrosine, valine and the like.

The above-mentioned active hydrogen compound is a polyolefin that cannot be obtained by a conventional primer, a fluorine resin such as Teflon,
This is to activate the surface of the difficult-to-adhesive agent and the like in order to strengthen the adhesive strength of the difficult-to-adhere material such as PPS, and also to activate the silane compound. Therefore, when the primer of the present invention containing this active hydrogen compound is used, the overcoating agent can be cured very rapidly and firmly as compared with the conventional adhesion mechanism.

The compounding ratio of the compound having an active hydrogen group is 0.0001.
It is more than part by weight. In this case, a preferable blending ratio when using a compound other than alcohol as the hydrogen compound is 0.0001 to 1
If it is 0.0001 parts by weight or less, sufficient adhesive strength may not be obtained, and if it is 1 part by weight or more, the strength of the overcoat layer such as the adhesive, coating material and printing ink to the adherend decreases. May occur.

In addition, the silane compound having an amino group or a mercapto group as the first component may be blended as the amine or mercaptan as the second component, not as the first component, and in this case, the amount of the second component blended. Can be a combination of the amount in the range defined as the amount of the second component and the amount of the first component. On the other hand, it may be possible to blend the second component, amine or mercaptan, as the first component rather than as the second component.

Further, when an alcohol corresponding to the active hydrogen compound of the second component is used as a solvent in an amount such that the effect of the present invention can be obtained, it may not be necessary to further mix the active hydrogen compound as the second component. On the other hand, alcohol can be added not as a solvent but as the active hydrogen compound of the second component, in which case the proportion of alcohol as the second component is 0.0001 to 99 parts by weight.

The overcoat agent such as an adhesive or paint used for the non-polar or highly crystallized resin treated with the primer of the present invention is, for example, a reactive adhesive or synthetic rubber or polyurethane made of silicone resin, acrylic resin, epoxy resin or the like. Is a non-reactive adhesive composed of, for example, an instant adhesive containing α-cyanoacrylate as a main component, and when a monomer copolymerizable with these overcoating agents is further added to the above components and blended, In some cases, the adhesiveness to the adherend such as a nonpolar or highly crystallized resin is improved by improving the affinity with the silane compound, and particularly when using an adhesive containing α-cyanoacrylate as a main component. Is α-methyl styrene, methyl methacrylate, methacrylic acid, methacrylonitrile, isobutyl vinyl ether, phenyl vinyl sulfide, vinegar Vinyl, ethyl vinyl sulfide 0-5 parts by weight of a monomer copolymerizable with α- cyanoacrylates such as styrene, particularly preferably 0.0001 to 0.5
A primer having good adhesiveness can be obtained by blending parts by weight, particularly preferably 0.0001 to 0.5 parts by weight.

Here, α-cyanoacrylate is represented by the following general formula.

R in the above formula includes alkyl, alkenyl, cyclohexyl, aryl and alkoxyalkyl groups and the like, specifically, methyl, ethyl, n-propyl, n-butyl, isobutyl, n-bentyl, allyl, cyclohexyl, benzyl, Examples thereof include a methoxypropyl group.
These α-cyanoacrylates may contain, for example, stabilizers, thickeners, colorants, fragrances, etc., if necessary.

Next, the above-mentioned primer is used by applying it when adhering a nonpolar or highly crystallized resin using the above-mentioned overcoating agent, and controlling the coating thickness at the time of use has the effect of the present invention. Desirable to fully exert,
Therefore, it is preferable to use the primer in the form of a solution, in which case a solvent may be added, and the solvent is not particularly limited, but it is an organic solvent capable of dissolving or dispersing the primer, and preferably It has a suitable volatility and can wet the surface of a non-polar or highly crystallized resin.

Further, the above-mentioned primer may contain a stabilizer, a colorant and the like, if necessary.

Further, in order to obtain the primer according to the present invention, the above components may be mixed.

Furthermore, when the primer of the present invention is used as an adhesive of nonpolar or highly crystallized resin, an undercoating agent for paints, etc., for example, when a nonpolar or highly crystallized resin material is combined and adhered as an adherend. Both surfaces, and in the case of a combination of a non-polar or highly crystallized resin material and a polar material, only the former direction can be immersed in the primer solution for a few seconds or brushed, sprayed, etc. The adherend coated with the primer is air dried to remove the solvent.

In order to exert the effect of the present invention more effectively, the specific components of the primer to be used and the compounding amount, coating amount, etc. of the adherend are determined in consideration of the material of the adherend and the properties of the overcoat material such as the adhesive. Must.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. In the examples and comparative examples, "part" means "part by weight".

(Examples of the invention) Examples 1 to 3 The following primer solutions were applied to one surface of each of the following two adherends (of the same kind) and air-dried for 1 to 2 minutes, and then the surface of one adherend An adhesive agent was applied on the primer coating film formed above, and the primer coating surface of the other adherend was superposed on the adhesive coated surface.

The composition of the primer, adherend and adhesive used in Examples 1 to 3 are as follows.

Primer Example 1: γ-aminopropylmethyldiethoxysilane 1 part thiophenol 0.03 part α-methylstyrene 0.01 part Example 2: γ-aminopropyltriethoxysilane 1 part 2-mercaptoethanol, 0.03 part Example 3: 3 -Aminopropyltriethoxysilane 1 part o-toluenethiol 0.03 part The primer of each of Examples 1 to 3 was prepared by adding chlorsene reagent first grade (manufactured by Asahi Kasei Co., Ltd.) to a total amount of 100 g.

Substrate (a) Polyethylene plate (25 x 100 x 2 mm) (b) Polypropylene plate (25 x 100 x 2 mm) (c) Polybu template (25 x 100 x 2 mm) Adhesive ThreeBond 1741 (Cyanoacrylate adhesive,
Three Bond Co., Ltd., trade name Comparative Example 1 The same adherend as the one used in Examples 1 to 3 using a polyprimer (trade name, manufactured by Toagosei Co., Ltd.) as a primer ( (A), (b), and (c) are applied to one surface of each of two sheets (same type), and the adhesive used in Examples 1 to 3 is used, and a bonding plate is manufactured in the same manner as in Examples 1 to 3. Was formed.

Examples 4 to 6 The adherends were bonded in the same manner as in Example 1 using the following primer, adherend and adhesive.

Primer Example 4: γ-aminopropylmethyldiethoxysilane 1 part Thiophenol 0.03 part α-methylstyrene 0.01 part Example 5: γ-aminopropyltriethoxysilane 1 part 2-mercaptoethanol, 0.03 part Example 6: 3 -Aminopropyltriethoxysilane 1 part o-toluenethiol 0.03 part The primer of each of Examples 4 to 6 was prepared by adding chlorocene reagent first grade (manufactured by Asahi Kasei Co., Ltd.) to a total amount of 100 g.

Substrate (material with poor adhesion) (d) Teflon plate (25 x 100 x 0.5 mm) (e) PPS (polyphenylene sulfide) (25 x 70 x 2 mm) (c) Silicone rubber (25 x 70 x 3 mm) Adhesion Agent TB 1741 (Cyanoacrylate adhesive, trade name, manufactured by ThreeBond Co., Ltd.) Comparative Example 2 Examples 4 to 6 except that the same primer (polyprimer) as that used in Comparative Example 1 was used. The adherends were joined in the same manner.

Example 7 An adherend was joined in the same manner as in Example 1 using the following primer, adherend and adhesive.

Primer The same primer as in Example 1 was used.

Substrate (g) Polyethylene plate (25 × 100 × 2 mm) Adhesive TB 1741 (Cyanoacrylate adhesive, manufactured by ThreeBond Co., Ltd., trade name) Comparative Example 3 The primer used in Comparative Example 1 was used. The adherends were bonded in the same manner as in Example 7 except for the above.

Evaluation test (A) Tensile-shear adhesive strength test After applying a compression load of 0.1 kgf / cm ² to each of the adherends of the adherends obtained in Examples 1 to 6 and Comparative Examples 1 to 2 described above, and then curing them for 24 hours. In accordance with JIS K6861-1977, the tensile shear strength was measured at a tensile speed of 10 cm / min using a Tensilon TMI tester. The measurement results are shown in Tables 1 and 2.

(B) Heat and Water Resistance Test Each joint plate of the adherends obtained in Example 7 and Comparative Example 3 was subjected to compression load of 0.1 kg / cm ² for 24 hours, and then heated with hot water for 4 hours.
After boiling for a period of time and subsequent air cooling, the tensile shear strength was measured in the same manner as in the tensile shear adhesive strength test described above. The measurement results are shown in Table 3.

Examples 8 to 52 The primers shown in Table 4 were each applied to the following two adherends (of the same kind) and air-dried for 1 to 2 minutes, and then formed on the surface of one adherend. A cyanoacrylate adhesive (TB 1741, manufactured by ThreeBond Co., Ltd., trade name) is applied on the primer coating, and the primer coating of the other adherend is overlaid on the surface coated with this adhesive. A joint plate was obtained together. The silane compounds A to C in Table 4 are as follows.

Silane compound A: Aminomethyltrimethoxysilane B: 3-Aminopropylmethyldiethoxysilane C: Mercaptomethyltrimethoxysilane Adherend (h) Polypropylene plate (25 x 100 x 2 mm) (b) Polyethylene plate (25 x 100 × 2mm) Evaluation Test (Tensile Shear Adhesive Strength) After compressing a load of 0.1 kgf / cm ² to each of the bonded plates of the adherends obtained in the above Examples 8 to 52 and curing them for 24 hours, JIS K6861-19
Tensile speed 10 using the Tensilon MI tester according to 77
The tensile shear strength was measured at cm / min. The measurement results are shown in Table 5.

Examples 53 to 54 Each of the following primer solutions was applied to one surface of the following two adherends (of the same kind), air-dried for 1 to 2 minutes, and then formed on one surface of the adherend. An adhesive was applied on the coating film, and the primer coating surface of the other adherend was superposed on the surface coated with the adhesive.

The compositions of the primers, adherends and adhesives used in Examples 53 and 54 are as follows.

Primer 3-aminopropylmethyldimethoxysilane 0.5 part Methyl alcohol 99.5 parts Adherend Example 53: Polyethylene (25 × 100 × 2 mm) Example 54: Polypropylene (25 × 100 × 2 mm) Adhesive TB1741 (manufactured by ThreeBond Co., Ltd.) Trade name) Evaluation test Each of the adherends of the adherends obtained in Example 53 above was subjected to a compression load of 0.
After adding 1kgf / cm ² and curing for 24 hours, in accordance with JIS K6861-1977, pulling speed 10cm using Tensilon MI tester
The tensile shear strength was measured at / min. The results are 49 kg / cm ² for the joining plate using the polyethylene plate (Example 53) and 46 kg / cm ² for the joining plate using the polypropylene plate (Example 54). Caused the base material destruction.

Examples 55 to 56 Each of the following primer solutions was applied to one surface of the following two adherends (of the same kind), air-dried for 1 to 2 minutes, and then formed on one of the adherends. An adhesive was applied on the coating film, and the primer coating surface of the other adherend was superposed on the surface coated with the adhesive.

The compositions of the primers, adherends and adhesives used in Examples 55 and 56 are as follows.

Primer 2-aminoethylaminomethyl methoxysilane 0.1 part N-decyl mercaptan 0.01 part Solvent Chlorosene (trade name of Asahi Kasei Co., Ltd.) 95% Adherend Example 55: PPS (25 × 70 × 2 mm) Example 56: Polyurethane (25 x 100 x 2 mm) Adhesive TB1781 (trade name of ThreeBond Co., Ltd.) Comparative Examples 4 to 5 The following adhesive was applied to the adherends used in Examples 55 and 56 without using a primer. , A bonded plate was obtained.

Adherends Comparative Example 4: PPS (25 x 70 x 2 mm) Comparative Example 5: Polyurethane (25 x 100 x 2 mm) Adhesive TB1781 (trade name of ThreeBond Co., Ltd.) Evaluation test Examples 55 to 56 and Comparative Examples After applying a compression load of 0.1 kgf / cm ² to each bonded plate of the adherends obtained in 4 to 5 and culturing for 24 hours, the tensile speed is 10 cm / min using a Tensilon MI tester in accordance with JIS K6861-1977. The tensile shear strength was measured by. The results are shown in Table 6.

(Effects of the Invention) As described above, according to the present invention, by using the primer of the present invention, it is possible to perform adhesion, coating, printing, etc. of difficult-to-adhere materials such as non-polar or highly crystallized resins. In this case, it is possible to remarkably improve the adhesive strength, the curing rate, the water resistance and the heat resistance, and in particular, the shortcomings of the instant adhesive containing α-cyanoacrylate as the main agent, which has been difficult to adhere for a long time due to the influence of humidity, are It has been resolved and enables sufficient adhesion for a long period of time. Therefore, the production line time can be greatly shortened, the production cost can be remarkably reduced, and the application range of the nonpolar or highly crystallized resin can be greatly expanded.

Claims (1)

[Claims] 1. A compound having at least one (a) [(C _n H _{2n + 1} ) O] group (wherein n is an integer of 1 to 6) and having either an amino group or a mercapto group. A mixture of the first component of the silane compound having, and (b) the second component of the compound having an active hydrogen group consisting of mercaptan, alcohol, carboxylic acid, or amine, wherein the first component has an amino group. In the case of a silane compound having, the second component is a compound having an active hydrogen group of any one of mercaptan, alcohol and carboxylic acid, and when the first component is a silane compound having a mercapto group, the second component is an alcohol. A primer for a cyanoacrylate-based adhesive, which is a compound having an active hydrogen group of carboxylic acid or amine.