JPH01240579A - Coating compound for elastomer/metal complex member, coating of said member and elastomer/metal complex member coated with said coating compound - Google Patents

Abstract

PURPOSE:To obtain the subject coating compound suitable as a coating film of rubber vibration insulator such as engine mounts, etc. equipped for reducing transfer of vibration of automobile engine, by blending a solution containing polyurethane with a rust preventive capable of forming a chelate with a metal. CONSTITUTION:(A) A solution containing a polyurethane prepared by reacting (i) a polyol with (ii) a polyisocyanate optionally in the presence of a chain extender is blended with (B) (iii) a rust preventive which is shown preferably by the formula and is capable of forming a chelate with a metal and (iv) rust- preventive pigment to give a coating compound for elastomer/metal complex member. Rubber vibration insulator is preferable as the complex member.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an elastomer/metal composite member in which an elastomer and a metal are bonded directly or with an adhesive or the like to form an integral shape, particularly for automobile engines. engine mount installed to reduce vibration transmission, muffler support that supports the exhaust pipe, Guinami Soku damper mound,
When a coating film is applied to other anti-vibration rubber members, etc., the coating film on a portion of the elastomer will not develop defects such as cracking, peeling, blistering, or shrinkage due to various distortions during engine operation or automobile driving. , as well as the ability to prevent rust on metal parts (corrosion paint,
The present invention also relates to a coating method using the same and a coated member obtained therefrom.

(Prior art and its problems) Traditionally, for elastomer/metal composite parts in which the elastomer and metal are integrally formed, rust-proofing has been applied to ordinary alkyd resins in consideration of rust prevention of the metal parts. It is coated with an anti-rust paint containing pigments.

For this reason, conventional paints have a certain level of rust prevention on the metal parts of elastomer/metal composite members, but they do not adhere well to elastomers, especially when used as automobile parts, and are difficult to transport when transporting new cars. There was a problem in that the coating film peeled off on a portion of the elastomer during the run or during the run.

On the other hand, paints that adhere to elastomers (for example,
1-43635), the rust prevention ability of the metal part was poor.

In this way, by painting the entire elastomer/metal composite member, conventional paints could not solve both the problems of adhesion to the elastomer and rust prevention of the metal parts at the same time.

(Solution Means) Here, in view of the above-mentioned actual situation, the present inventors have proposed that in a coating film applied entirely to an elastomer/metal composite member,
The results of intensive research into paints and coating methods that do not cause cracking, peeling, shrinkage, blistering, etc. on the elastomer parts and have excellent rust prevention properties on the metal parts, as well as coated elastomer/metal composite parts. discovered that all of these problems could be solved by coating a polyurethane-containing solution with a specific rust preventive agent or a paint containing a rust preventive pigment together with the rust preventive agent, and completed the present invention. It has come to this.

That is, the present invention provides a solution containing a polyurethane obtained by reacting a polyol and a polyisocyanate, optionally in the presence of a chain extender, with a rust preventive agent capable of forming a chelate with a metal, or a rust preventive agent capable of forming a chelate with a metal. A paint for elastomer/metal composite parts containing a rust preventive pigment together with a rust agent, a coating method for elastomer/metal composite parts that involves applying the paint, and a coating obtained by applying such a paint The present invention provides an elastomer/metal composite member having a film, and in particular, the elastomer/metal composite member is anti-vibration rubber for automobiles, etc.; The object of the present invention is to provide a method for coating a composite member, and an elastomer/metal composite member having a coating film formed with the paint.

The present invention also provides a coating for elastomer/metal composite parts, which uses a compound represented by the following formula as a rust preventive that can form a chelate with a metal, and coating of the composite part coated with such a paint. An object of the present invention is to provide an elastomer/metal composite member coated with such a coating.

Furthermore, the present invention provides a paint for an elastomer/metal composite member, which comprises using zinc oxide as a rust preventive pigment used together with a rust preventive agent capable of forming a chelate with a metal, and a composite member to which such a paint is applied. The present invention provides a coating method and an elastomer/metal composite member coated with such a coating.

By the way, the polyurethane used in the present invention is a resin obtained by reacting a polyol and a polyisocyanate, and further, if necessary, a chain extender according to a conventional method.

The polyols include ethylene glycol, propylene glycol, 1.3-7'tanediol,
1,4-butanediol, 1,6-hexanediol,
Low molecular weight polyols such as neopentyl glycol, diethylene glycol, dipropylene glycol, triethylene glycol, cyclohexane dimetatool; and polyether glycols such as polyethylene glycol, polypropylene glycol, poly(1,4-butanediol), polyethylene propylene glycol; The low molecular weight polyol and/or polyether glycol,
A polyester polyol or polyether ester polyol obtained by reacting with a tribasic acid such as succinic acid, adipic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid; High molecular weight polyols such as polycaprolactone polyol obtained by a ring-opening reaction of caprolactone; polyurethane polyol having a hydroxyl group at the end, which is a reaction product of the various polyols mentioned above and polyisocyanate; and the like will be used.

In addition, examples of polyisocyanates that can be reacted with these polyols and a chain extender that is present as necessary include hexamethylene diisocyanate, 2,6-
Diycyanate methyl caproate, 4.4'-methylenebis(cyclohexyl isocyanate), 1.3-
or 1,4-bis(isocyanatomethyl)cyclohexane, methylcyclohexane-2,4- or -2,6-
Diisocyanate, diphenylmethane-4,4'-diisocyanate, 2,4- or 2,6-dolylene diisocyanate, 1,3- or 1,4-xylylene diisocyanate, 1,5-naphthalene diisocyanate, isophorone diisocyanate, and the like. In addition to dimers and trimers, reaction products of the above-mentioned polyisocyanate and the above-mentioned polyol having an isocyanate group at the end can be mentioned.

In addition to the above-mentioned low molecular weight polyols, the chain extenders used as necessary in the present invention include aliphatic polyamines,
There are those known in the art, such as aromatic polyamines, alicyclic polyamines, etc.

When forming a polyurethane resin by reacting such a polyol, polyisocyanate, and optionally a chain extender, the combination thereof and the equivalent ratio of NGOloH can be arbitrarily selected.
7) Equivalence ratio is 1.5/1.0~1, 0/1.
Selected from a range of 5.

In addition, a conventionally known method can be applied to the reaction of the polyol, polyisocyanate, and a chain extender used as necessary. The chain extension reaction is carried out by a chain extension reaction using an agent, or the reaction is carried out by simultaneously mixing and reacting a low molecular weight polyol and/or a high molecular weight polyol, a polyisocyanate, and a chain extension agent used as necessary.

Even if the reaction phase is a melt reaction that does not use a solvent, it is a reaction in a solvent that is non-reactive with polyisocyanates, such as ketone, ester, ether, aromatic or aliphatic hydrocarbons. It's okay. Furthermore, the reaction is usually carried out in the presence or absence of a catalyst such as a tin compound or an amine compound until almost no remaining NGO is present (for example, N
(G O content becomes 0.3% or less) by heating for an arbitrary period of time.

In addition, examples of rust preventives that can form chelates with metals used in the present invention include tannic acid, malic acid, thiomalic acid, citric acid, succinic acid, derivatives thereof, polytannic acid, etc. Among these, succinic acid derivatives represented by the following formula are preferably used.

Furthermore, in the present invention, the rust preventive pigment used in combination with the rust preventive agent that forms a chelate with the metal may be any pigment that is normally used in paints, such as iron oxide, iron oxide, etc. Compounds of various metal oxides such as lead and zinc oxide, various metal acids such as phosphoric acid, chromic acid, silicic acid, lead acid, and molybdic acid, and various metals such as zinc, lead, and calcium, and mixtures thereof, etc. However, particularly preferred are:
Zinc oxide is used.

In carrying out the present invention, the polyurethane resin described in ifI is used as a solution containing a solvent, and made into a paint according to a conventional method. When making a paint, the rust preventive agent of the present invention,
In addition to antirust pigments, pigments such as coloring pigments and extender pigments; additives such as antifoaming agents, pigment dispersants, antisettling agents, leveling agents, color separation prevention agents, and slipping agents; and ketones ,
Solvents such as esters, alcohols, ethers, glycol ethers, glycol ether esters, nitrogen-containing solvents, sulfur-containing solvents, aliphatic systems, aromatic systems, or halogenated hydrocarbons are contained as necessary to achieve the desired purpose. It is considered a paint.

Note that rust inhibitors that can form chelates with metals include:

The mixing amount is 0.01 to 10%, preferably 0.1 to 0.
．． It is used at a rate within the range of 5%. If the mixing amount is less than 0.01%, the rust preventive effect will not be observed, and if it is more than 10%, surface discoloration due to elution of the rust preventive agent will become significant.

Moreover, the rust preventive pigment used together with such a rust preventive agent is 0.
Any amount may be used as long as it is 1% or more, but preferably 1 to 15
It can be added in a range of %. If it is less than 0.1%, no effect of the combination is observed. The mixing amount of pigments including anti-rust pigments is such that the ratio of pigments/resin solid content is 0.1/1.
It is determined at a ratio of 0 to 3.0/1.0, but preferably a range of 0.1/1.0 to 1.5/1.0. Further, additives other than the rust preventive agent are added in an amount of about 0.01 to 10% to the above paint depending on the effect of the addition.

Furthermore, solvents are added appropriately depending on the viscosity of the reacted polyurethane resin, but usually the solid content is 10 to 5.
Added to give 0% paint.

Furthermore, the coating material of the present invention may contain an isocyanate prepolymer such as the polyisocyanate used in the reaction of the polyurethane resin, an adduct of these with a polyol such as trimethylolpropane, or a biuret combination thereof. It is also possible to mix. Thereby, the adhesion of the coating film can be further improved.

By the way, in the elastomer/metal composite part 1A to which the paint according to the present invention is applied or the elastomer/metal composite member coated by the method of the present invention, a portion of the elastomer is
It can be any elastomer molded from elastomeric materials commonly used in elastomeric moldings, including natural rubber, isoprene rubber, styrene-butadiene rubber, butadiene rubber, chloroprene rubber, ethylene- propylene rubber,
Acrylonitrile-butadiene rubber, butylcom, EP
There is DM etc. When molding the elastomer portion of the elastomer/metal composite member from these elastomer materials, commonly used additives such as reinforcing agents, fillers, softeners, plasticizers, tackifiers, anti-aging agents, colorants,
Additives such as vulcanization aids, crosslinking agents, vulcanization accelerators, and scorch inhibitors are added. Among these additives, anti-aging agents such as amine-ketone-based, aromatic secondary amine-based, alkylphenol-based, thiourea-based, penzimidazur-based anti-aging agents, and waxes are used. is normal.

Additionally, the metal portion of such an elastomer/metal composite member can be any metal made from conventional ferrous metals, non-ferrous metals, and such metal materials include:
iron, steel, cast iron, stainless steel and other iron and their alloys;
Any metal can be used, such as aluminum and its alloys, copper and its alloys.

Note that the elastomer/metal composite member in the present invention is not particularly limited as long as the elastomer portion and the metal portion each have the above-described compositions. Suitable examples of such composite members include anti-vibration rubber for engine mounts, muffler supports, dynamic damper supports, etc., rubber rolls, bell seats, hoses, etc. in automobile parts.

When applying the paint of the present invention to the elastomer/metal composite member of the present invention, it is preferable to surface-treat the composite member using various methods. In that case, the surface treatment method is appropriately selected from sandpaper treatment, sand, grid, or shot blasting treatment, solvent wiping treatment, solvent immersion treatment, chemical conversion treatment, solvent vapor treatment, or a combination thereof. .

Furthermore, when applying the paint of the present invention, it is diluted with various solvents or mixed solvents thereof used in forming the paint, if necessary. As a method for such application, methods used for general paint application, such as brush application, dip application, shower application, air spray application, airless spray application, and electrostatic application, can be used as appropriate.

and an elastomer coated with the paint according to the invention/
The metal composite member may be dried by leaving it at room temperature, but preferably at a temperature of 50 to 120°C.
It is dried by heating for an arbitrary period of time, and an effective coating film is formed.

(Examples) Examples of the present invention will be shown below to clarify the present invention more specifically, but the present invention is not limited in any way by the description of such examples. It goes without saying that this is not the case.

In the following Examples and Comparative Examples, the amounts in the coating compositions are in parts by weight, and the percentages in the coating compositions are in weight %.

・ 11-6 Rokuri 11-4 First, polycaprolactone polyol (manufactured by Daicel Chemical Industries, Ltd., Plaxel) with a molecular weight of about 13 (10) and 4,4'-methylenebis(cyclohexyl isocyanate) are mixed with 70-I OO' After reacting with C, 1,4-butanediol, which is a chain extender, was added, and further 80 to 1
A polyurethane resin is produced by carrying out a chain extension reaction at a temperature of 50'C until the NGO content becomes 0.2% or less,
Then, toluene/isopropyl alcohol = 1/1
A polyurethane resin solution A having a solid content of 30% was prepared by dissolving the resin in a mixed solvent.

In addition, polycaprolactone polyol (manufactured by Daicel Chemical Industries, Ltd., Plaxel) with a molecular weight of about 2 (100) and 4,4'-methylene bis(cyclohexyl isocyanate) are reacted at 70 to 1 (10°C), and then the chain Add ethylene glycol as an extender and further increase the temperature to 80 to 150
A polyurethane resin was produced by chain extension reaction until the NGO content became 0.2% or less, and dissolved in a mixed solvent of toluene/isopropyl alcohol = 1/l.
A polyurethane resin solution B having a solid content of 25% was prepared.

On the other hand, oil length 30 is composed of phthalic anhydride, pentaerythritol, dehydrated castor oil fatty acid, and neopentyl glycol.
, an alkyd resin with an acid value of 2.0 was synthesized, and this resin was dissolved in xylene to prepare an alkyd resin solution with a solid content of 50%.

Then, using the two types of polyurethane resin solutions A and B obtained in this way and the above alkyd resin solution,
As shown in Tables 1 and 2 below, this example (No.
, 1 to 6) and comparative examples (Nα1 to 4), and after adjusting the coating viscosity with a solvent, the coated rubber members were heated at 70°C for 2 hours.
Forced dry for 0 minutes.
Using the various coated parts thus obtained, a cyclic strain test and a salt spray test were conducted, and the results are shown in Tables 1 and 2 below, respectively.

In addition, in the repeated strain test, after applying the anti-vibration rubber paint and letting it dry, the elastomer content was 1 (±30% at a speed of 10 times/min) and 2 (±30% at a rate of 10 times/min). The condition was observed, and the results were as follows: ◎: No abnormality, ○: 1 to 5 wrinkles, Δ: 1 to 5 cracks or peeling, ×: 5 wrinkles or cracking/peeling. In the salt spray test that was evaluated, the paint was applied to a solvent-degreased rubber member and allowed to dry, then two kucuts were inserted into the metal parts using a knife until they reached the base material, and salt water was sprayed for 96 hours to test the paint film. Observe the state of creep width (◎: less than 1 m, ○: 1.
Less than Omm, △: 3. Less than Omm, 3,0 mm
above), and the state of the flant portion (◎: x, ○: less than 5% rust or blisters, △: less than 20% rust or blisters, ×: 2 degrees higher than rust or blisters).

As is clear from the explanation, when the paint according to the present invention is applied to a composite member in which an elastomer and a metal are integrated, it has excellent adhesion to both the elastomer part and the metal part. In addition, it follows the repeated strain of the elastomer part, and the paint film does not peel, peel, blister, shrink, etc., and also has excellent rust prevention properties for metal parts, so it is different from conventional paints. In particular, it has become possible to effectively coat elastomer/metal composite members, where peeling of a part of the elastomer has been a problem, and this is where the present invention has great industrial significance.

Claims (12)

[Claims] (1) A solution containing a polyurethane obtained by reacting a polyol and a polyisocyanate, optionally in the presence of a chain extender, is added with a rust preventive agent capable of forming a chelate with a metal, or together with the rust preventive agent. A paint for elastomer/metal composite parts that is characterized by containing pigments. (2) The paint for an elastomer/metal composite member according to claim (1), wherein the composite member is a vibration-proof rubber. (3) The paint for an elastomer/metal composite member according to claim (1), wherein the rust preventive agent capable of forming a chelate with the metal is represented by the following formula. ▲Contains mathematical formulas, chemical formulas, tables, etc.▼ (4) The paint for an elastomer/metal composite member according to claim (1), wherein the rust preventive pigment used together with the rust preventive agent capable of forming a chelate with the metal is zinc oxide. (5) A rust preventive agent capable of forming a chelate with a metal, or a rust preventive agent together with the rust preventive agent, is added to a solution containing a polyurethane obtained by reacting a polyol and a polyisocyanate, optionally in the presence of a chain extender. A method for coating an elastomer/metal composite member, which comprises applying a paint containing a pigment to the elastomer/metal composite member. (6) The method for coating an elastomer/metal composite member according to claim (5), wherein the elastomer/metal composite member is a vibration-proof rubber. (7) The method for coating an elastomer/metal composite member according to claim (5), wherein the rust preventive agent capable of forming a chelate with the metal is represented by the following formula. ▲Contains mathematical formulas, chemical formulas, tables, etc.▼ (8) The method for coating an elastomer/metal composite member according to claim (5), wherein the rust preventive pigment used together with the rust preventive agent capable of forming a chelate with the metal is zinc oxide. (9) A rust preventive agent capable of forming a chelate with a metal, or a rust preventive agent together with the rust preventive agent, is added to a solution containing a polyurethane obtained by reacting a polyol and a polyisocyanate, optionally in the presence of a chain extender. An elastomer/metal composite member with a coating film formed from a paint containing pigments. (10) The elastomer/metal composite member according to claim 9, wherein the elastomer/metal composite member is a vibration-proof rubber. (11) The elastomer/metal composite member according to claim (9), wherein the rust preventive agent capable of forming a chelate with the metal is represented by the following formula. ▲Contains mathematical formulas, chemical formulas, tables, etc.▼ (12) The elastomer/metal composite member according to claim 9, wherein the rust preventive pigment used together with the rust preventive agent capable of forming a chelate with the metal is zinc oxide.