JP2001262069A - Coating composition containing gluconic acid derivative salts - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly stable coating which is free from harmful metals such as chromium, lead, etc., and has a corrosion resistance which is identical to or higher than that of chromium, lead, etc., by using a non-toxic or low-toxic anticorrosive. SOLUTION: The coating composition contains gluconic acid derivative salts of the formula: R1-[CH(OH)]4-COO-X+ (wherein R1 is -CHO, -CH2OH or -COO-X+; and X+ is a metal ion, an alkyl ammonium ion, a sulfonium ion or an ammonium ion).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel pollution-free paint having excellent anticorrosion properties by containing gluconic acid derivative salts in the paint.

[0002]

2. Description of the Related Art Conventionally, rust-preventive pigments used in organic solvent-based paint compositions, aqueous paint compositions, and the like include chromium-based pigments (eg, zinc chromate, strontium chromate). ), Lead-based pigments (for example, lead red, basic lead chromate,
Cyanamide lead, calcium plumbate, etc.) are known. However, these rust-preventive pigments are very harmful substances, and there is a problem in their use in terms of pollution control and effects on human bodies. Non-toxic or low-toxic rust-preventive pigments have been studied in place of the lead compounds and chromium compounds.However, no rust-inhibiting pigments having the same rust-preventive properties as the lead compounds and chromium compounds described above have been found. However, there are still problems to be improved, such as lowering the storage stability of some resin-based paints.

[0003]

Means for Solving the Problems The present inventors have conducted intensive studies to find a non-toxic or low-toxic rust inhibitor that does not contain harmful metals such as chromium and lead. It has been found that the above problem can be solved by adding the compound to the paint, and the present invention has been completed. That is, the present invention provides: A coating composition comprising a gluconic acid derivative salt represented by the general formula (1),

[0004]

Embedded image General formula (1) (R ₁ represents —CHO, —CH ₂ OH, or —COO ⁻ X ⁺ , and X ⁺
Represents a metal ion, an alkyl ammonium ion, a sulfonium ion, or an ammonium ion. ) 2. The coating composition according to claim 1, wherein in the general formula (1), R ₁ is —CH ₂ OH and X ⁺ is an alkali metal ion, an alkaline earth metal ion, a transition metal ion, or an amphoteric metal ion. 3. 3. The coating composition according to item 1, wherein in the general formula (1), X ⁺ is a Na ion, a K ion, a Mg ion, or a Ca ion. 4. The coating composition according to claim 1, wherein in the general formula (1), X ⁺ is an Fe ion, an Al ion, or a Zn ion. 2. The coating composition according to item 1, wherein in the general formula (1), X ⁺ is a quaternary alkyl ammonium ion.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the composition of the present invention will be described in detail. In the general formula (1), the metal ion includes an alkali metal ion, an alkaline earth metal ion, and a transition metal ion. As the alkali metal ion, for example,
Li ⁺ , Na ⁺ , K ⁺ , Rb ⁺ , and Cs ⁺ . Among them, Na ⁺ and K ⁺ are preferable. Examples of the alkaline earth metal ion include Be ²⁺ , Mg ²⁺ , Ca ²⁺ , Sr ²⁺ ,
Ba ^{2+ and the} like. Among them, Mg ²⁺ and Ca ²⁺ are preferable. Transition metal ions include Zr ²⁺ , Mn ²⁺ , Ni ²⁺ ,
There are Co ²⁺ , Cu ²⁺ , Zn ²⁺ , W ³⁺ , Mo ³⁺ , and Fe ³⁺ . Among them, Zn ²⁺ and Fe ³⁺ . Al ³⁺ is an amphoteric metal ion. Examples of the alkyl ammonium ion include a monoisopropyl ammonium ion, a monobutyl ammonium ion, a dibutyl ammonium ion, a 3-methyl-3-amino-propanol ion, a tributyl ammonium ion, a tetrabutyl ammonium ion, and a dodecyl trimethyl ammonium ion. Among them, the quaternary alkyl ammonium ions dodecyltrimethylammonium ion and tetrabutylammonium ion are preferred.

[0005] R ₁ is -CHO, -CH ₂ OH, or -CO
O ⁻ X ⁺ is mentioned, and among them, —CH ₂ OH is suitably used.

In the compound of the general formula (1), X ⁺ represents a metal ion such as sodium D-gluconate,
Sodium D-glucuronate, sodium D-glucarate, sodium D-galactonate, potassium D-gluconate, potassium D-glucuronate, potassium D-glucarate, potassium D-galactonate, calcium D-gluconate, D- Calcium glucuronate, calcium D-glucarate, calcium D-galactonate, magnesium D-gluconate, magnesium D-glucuronate, D
-Magnesium glucarate, magnesium D-galactonate, aluminum D-gluconate, aluminum D-glucuronate, aluminum D-glucarate, aluminum D-galactonate, zinc D-gluconate, zinc D-glucuronate, D-glucal Examples include zinc acid, zinc D-galactonate, iron D-gluconate, iron D-glucuronate, iron D-glucarate, and iron D-galactonate.

Examples of the alkylammonium ion represented by X ⁺ include monoisopropylammonium D-gluconate, monoisopropylammonium D-glucuronate, monoisopropylammonium D-glucarate, monoisopropylammonium D-galactonate,
Monobutylammonium D-gluconate, monobutylammonium D-glucuronate, monobutylammonium D-glucarate, monobutylammonium D-galactonate, dibutylammonium D-gluconate, dibutylammonium D-glucuronate, D-glucaric acid Examples include dibutylammonium and dibutylammonium D-galactonate.

In the present invention, the coating composition used for blending the gluconic acid derivative salts can be selected from conventional coating systems without any particular limitation. Specific examples include an organic solvent type coating composition and an aqueous type coating composition. First, an organic solvent type paint containing a gluconic acid derivative salt will be described below. The gluconic acid derivative salts used in the present invention can be dissolved in an organic solvent type paint or dispersed together with a pigment, and can be used as a pigment dispersion paste.

Specifically, R ₁ is —CH ₂ OH, and X ⁺ is N
Since gluconic acid derivative salts such as sodium D-gluconate, which is a ⁺ , are partially soluble or insoluble in an organic solvent, they can be co-existed with a resin together with a coloring pigment, an extender pigment, and other rust-preventive pigments. By using a pigment paste obtained by dispersion, a paint having excellent stability can be obtained.

Further, when R ₁ is -CH ₂ OH and alkylammonium ion is used as X ⁺ , the solubility in an organic solvent is improved as compared with the case where X ⁺ is a metal ion. , The frequency of contact with the corrosion accelerating substance that has entered from the outside in the coating film increases, and the rust prevention effect is large. The alkylammonium ion preferably has 3 to 20 carbon atoms.
When the number of carbon atoms is less than 3, the stability in the coating is insufficient, and when the number of carbon atoms exceeds 20, the performance of the coating film is deteriorated.

Specific examples of the organic solvent type paint include acrylic resin paints, alkyd resin paints, polyester paints, epoxy resin paints, amino resin paints (melamine resins, benzoguanamine resins, urea resins and amine compounds). Paints using methylolated compounds and alkyl etherified compounds), cellulose derivative paints (nitrocellulose lacquer, acetylcellulose lacquer, acetylbutylcellulose lacquer, ethylcellulose lacquer, etc.), urethane resin paints, vinyl chloride resin paints, fluororesin paints Paints, vinyl acetate resin paints, styrene-butadiene resin paints, vinyl chloride organosol paints, and the like.

The organic solvent type paint used in the present invention can be used without any particular limitation in any of a non-crosslinked type (lacquer type) and a crosslinked type. As the cross-linking type, for example, any of a thermosetting type and a room temperature setting type can be used. Examples of the thermosetting type include a hydroxyl group-containing resin (acryl, epoxy, polyester, etc.) / Curing agent (amino resin, (block) polyisocyanate compound), polycarboxylic acid resin / epoxy curing agent, epoxy base resin / polycarboxylic acid Conventional curing types such as curing agents can be used.

The solvent used in the organic solvent type paint may be appropriately selected depending on the kind of the paint. Specifically, hydrocarbon solvents (hexane, heptane, etc.), alcohols (propanol, butanol, etc.) and ethers (ether, etc.) Ethyl cellosolve, butyl cellosolve, diethylene glycol monoethyl ether, etc., ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), esters (ethyl acetate, propyl acetate, butyl acetate, cellosolve acetate, etc.) can be used.

The content of the organic solvent in the coating is about 10 to 10%.
95% by weight, preferably about 20-90% by weight. If necessary, a pigment, a flow regulator, a pigment dispersant, a pigment dispersant, a plasticizer, a curing catalyst, a surface regulator, an ultraviolet absorber and the like can be added. As the above-mentioned pigment, those conventionally used can be used without limitation, for example, coloring pigments such as titanium oxide, carbon black, red iron oxide, aluminum paste, pearl powder, graphite, MIO, phthalocyanine blue; clay, mica, and barita ,
Extenders such as talc, calcium carbonate and silica; and rust preventive pigments such as zinc phosphate and iron phosphate.

The amount of the gluconic acid derivative salts is as follows:
The amount is 0.01 to 50 parts by weight, preferably 0.05 to 30 parts by weight, based on 100 parts by weight of the solid content of the resin. If the amount added is less than 0.01 part by weight, there is no effect on the corrosion resistance and
Exceeding 0 parts by weight is not preferred because the stability of the paint is impaired.

Next, a case where the present invention is applied to a water-based paint will be described below. In the general formula (1), -COO
^Although the solubility varies depending on the X ⁺ of -X ⁺ , the aqueous solution is neutral and has low toxicity, so that it is easy to handle. Alkali metal ions, such as Na ⁺ and K ⁺ , have good solubility in water, and also have an anticorrosion effect because they are uniformly present in the coating film even for external corrosion promoting substances. There is such a feature.

In the general formula (1), X ⁺
g ^2+, Ca alkaline earth metal ions such as ^2+, X ⁺ as Zn ^2+, Fe ³⁺ transition element such as ion, Al ³⁺ amphoteric metal ions those using and X ⁺ as alkyl ammonium ion, such as Gluconic acid derivative salts using is partially soluble or insoluble in water, and can be used as a dispersing paste together with coloring pigments, extender pigments, and other rust-preventive pigments. it can.

As the water-based coating composition, conventionally known water-soluble, water-dispersed or emulsion-type ones, anionic, cationic or nonionic ones can be used. The amount of the gluconic acid derivative salt to be added to the aqueous coating composition is, as in the case of the organic solvent-based coating composition, 0.01 to 50 parts by weight per 100 parts by weight of the resin solid content.
Parts by weight, preferably 0.05 to 30 parts by weight are good. If the amount is less than 0.01 part by weight, there is no effect on the anticorrosion property.

As the water-based coating composition, specifically,
Acrylic resin paints, alkyd resin paints, polyester paints, epoxy resin paints, amino resin paints (paints using melamine resin, benzoguanamine resin, urea resin, and methylolated or alkyletherified amine compounds), urethane Resin paints, vinyl chloride resin paints, fluororesin paints, vinyl acetate resin paints, styrene-butadiene resin paints, and the like.

The content of water in the paint is about 10 to 95% by weight, preferably about 20 to 90% by weight. If necessary, pigments, flow regulators, plasticizers, curing catalysts, coating surface regulators, ultraviolet absorbers and the like can be added. As the pigment, those conventionally used can be used without limitation, for example, titanium oxide, carbon black, red iron oxide, aluminum paste, pearl powder, graphite,
Coloring pigments such as MIO and phthalocyanine blue; extenders such as clay, mica, barita, talc, calcium carbonate and silica; and rust preventive pigments such as zinc phosphate and iron phosphate.

In addition to the above-mentioned organic solvent-based paints and water-based paints, solventless liquid paints, active energy ray-curable paints and powder paints can also be used. The composition of the present invention can form a cured coating film by applying the coating composition described above to a substrate and then subjecting the composition to heating or irradiation with active energy rays at room temperature.

The base material on which the coating composition is applied may be a metal base material such as aluminum, steel, zinc, tin, copper, stainless steel, or a plated metal base material having a steel surface plated with zinc, tin, aluminum, chromium, or the like. And a chemical conversion-treated metal substrate obtained by treating the surface of steel or the like with chromic acid, phosphoric acid, or the like.

The coating method of the coating composition includes, for example, brush coating, spray spray coating, roller coating, dip coating,
It can be applied to the base material surface by means such as electrostatic powder coating or electrodeposition coating. The amount of coating varies depending on the type of coating, coating means, purpose of use, etc., but is generally in the range of about 0.1 to 500 μm.

The conditions for drying the coating film can be selected according to the type of the coating composition. For example, a coating composition containing a hydroxyl group-containing acrylic resin as a base resin and a (blocked) polyisocyanate compound or a melamine resin as a cross-linking agent is considered to be sufficient at 80 ° C. to 150 ° C. for about 20 minutes to 120 minutes.

[0025]

The coating composition of the present invention is gluconic acid-derived
A cured coating film with excellent anticorrosion properties by containing body salts
Can be formed. Gluconic acid derivative salts are excellent
The reason for exhibiting the rust prevention effect is that Fe eluted from the base material
³⁺, Al³⁺, Zn ²⁺Gluconic acid induction with metal ions such as
The body is chelated and deposited on the metal surface,
A passivation film is formed on the metal surface to suppress corrosion on the metal surface.
Control effect and corrosion factor oxygen invading from the coating surface
Catch ions, chloride ions, etc.
By preventing particles from migrating to the interface between the coating and the metal
It is presumed to have a corrosion inhibiting effect.

[0026]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited by this. Note that “parts” and “%” indicate “parts by weight” and “% by weight”.

Production Example 1 of Pigment Paste a In a stirring and mixing container, 100 parts of Acridic A801 (trade name, acrylic resin, manufactured by Dainippon Ink and Chemicals, Inc.) and JR-7
01 (manufactured by Teica, trade name, titanium white) 80 parts, Tancar 200 (manufactured by Takehara Chemical Co., trade name, calcium carbonate) 20
Parts, Quartlet GL (manufactured by Teikoku Chemical Co., Ltd., trade name, 0.1 part of sodium gluconate, xylene-based solvent) and dispersed for 60 minutes using a desktop sand mill to obtain a pigment paste a having a solid content of 30% by weight. Production Example 2 b In the above Production Example 1, magnesium gluconate was added in an amount of 0.1%.
The same formulation as in Production Example 1 except that
% By weight of pigment paste b was obtained.

Preparation Example 3 of Pigment Paste C Pigment paste c having a solid content of 30% by weight was obtained in the same manner as in Preparation Example 1 except that 0.1 part of zinc gluconate was added in Preparation Example 1 described above.

Production Example 4 of Pigment Paste D Pigment paste d having a solid content of 30% by weight was obtained in the same manner as in Production Example 1 except that sodium gluconate was not used in Production Example 1 described above.

Production Example 5 of Acrylic Emulsion A for Water-Based Paint A reaction vessel was charged with 140 parts of deionized water, 2.5 parts of "Newcol-707SF" (manufactured by Nippon Emulsifier Co., surfactant, 30% solids) and a monomer mixture ( 55 parts of methyl methacrylate, 8 parts of styrene, 9 parts of n-butyl acrylate, 5 parts of 2-hydroxyethyl acrylate, 2 parts of 6-hexanediol diacrylate and 1 part of methacrylic acid). After stirring and mixing, 3 parts of 3% ammonium persulfate was added at 60 ° C. Then, the temperature was raised to 80 ° C., and the remaining 79 parts of the monomer mixture, “Newcol-707SF” 2.
5 parts, 4 parts of 3% ammonium persulfate and 42 parts of deionized water
Parts of the pre-emulsion was added to the reaction vessel over 4 hours using a metering pump, and aging was performed for 1 hour after the addition was completed. Further, at 80 ° C., a monomer mixture (5 parts of methyl methacrylate, 7 parts of n-butyl acrylate,
-5 parts of ethylhexyl acrylate, 3 parts of methacrylic acid and 2 parts of 0.5 parts of "Newcol-707SF" and 4 parts of 3% ammonium persulfate were simultaneously dropped in parallel over 1.5 hours, and 1 hour after the addition was completed. Aging time, add deionized water,
The pH was adjusted to 7.5 with dimethylethanolamine to obtain an acrylic resin emulsion A having an average particle size of about 0.1 μm and a solid content of 35%.

Production Example 6 of Pigment Paste e for Water-Based Coatings 10 parts of BYK-184 (manufactured by BYK-Chemie, pigment dispersant) and 80 parts of JR-701 (manufactured by Teica, trade name, titanium white) in a stirring and mixing vessel. , Tancal 200 (manufactured by Takehara Chemical Co., Ltd.
20 parts of trade name, calcium carbonate), 0.1 part of Qualette GL (trade name, manufactured by Teikoku Chemical Co., Ltd., sodium gluconate) and 0.1 parts of deionized water are added, and the mixture is dispersed for 60 minutes using a desktop sand mill.
A pigment paste e having a solid content of 30% by weight was obtained.

Production Example 7 of Pigment Paste f for Water-Based Paint The pigment paste f was produced in the same manner as in Production Example 6, except that 0.1 part of Qualette GL (trade name, manufactured by Teikoku Chemical Co., Ltd., sodium gluconate) was not used. Obtained.

Example 1 Sumidur N3300 (manufactured by Sumitomo Bayer Urethane Co., Ltd., trade name: Hexa) was added to 3 parts of the pigment paste a obtained in Production Example 1 in a stirring and mixing vessel so that the OH content / NCO content = 1/1. 17 parts of methylene diisocyanate (trimer of methylene diisocyanate) was added thereto, and the mixture was stirred with a disper. 1 was obtained.

Examples 2 and 3 The pigment paste b and the pigment paste c obtained in Production Examples 2 and 3 were mixed in the same manner as in Example 1 with a solid content of 32% by weight in Example 2 respectively. Paint No. 2 and Example 3
Paint NO. 3 was obtained.

Example 4 The aqueous acrylic emulsion A obtained in Production Example 5 was replaced with Production Example 6
Was added thereto, and the mixture was stirred with a disper.
4 was obtained.

Comparative Example 1 The paint No. having a solid content of 32% by weight of Comparative Example 1 was added to the pigment paste d obtained in Production Example 4 by the same blending and operation as in Example 1. 5 was obtained.

Comparative Example 2 The paint No. having a solid content of 32% by weight of Comparative Example 2 was mixed with the pigment paste f obtained in Production Example 7 by the same composition and operation as in Example 1. 6 was obtained. Table 1 shows the contents of Examples and Comparative Examples.

[0038]

[Table 1]

Preparation of Coating Test 0.8 × 15 chemically treated with Palbond # 3020 (trade name, zinc phosphate treating agent, manufactured by Nippon Parkerizing Co., Ltd.)
The paints obtained in Examples and Comparative Examples were applied to a cold rolled dull steel sheet of 0 × 70 mm by spray coating so that the dry film thickness became 20 μm. Baking is performed at a surface temperature of the substrate of 8
Performed at 0 ° C. for 30 minutes, and performed using an electric hot air drying oven.
Table 2 shows the results of the coating film performance test.

[0040]

[Table 2]

(Note 1) Corrosion protection: baking temperature 80 ° C-3
On each coated plate obtained in 0 minutes, make a cross-cut wound on the coating film with a cutter knife so as to reach the base, and apply this to JISZ
A salt water spray test was performed for 480 hours in accordance with -2371, and evaluated according to the following criteria based on the scratches from the cut portion, blister width, and the coated surface condition (blister) of the general portion. ○ indicates no blistering when the maximum width of rust and blisters is less than 2 mm (one side) from the cut portion. Δ indicates that the maximum width of rust and blisters is 2 mm or more and less than 3 mm (one side) from the cut portion, and blisters are observed on a part of the coated surface. × indicates that the maximum width of rust and blisters is 3 mm or more from the cut portion and blisters are generated on the entire coated surface. (Note 2) Water-resistant secondary adhesion: Each coated plate obtained at a baking temperature of 80 ° C. for 30 minutes was immersed in warm water of 40 ° C. for 168 hours, and a 2 mm square gobang cut was made, and then Cellotape (registered trademark) ) Peel off and evaluate the remaining coating film. Remaining number / 100: ○ is 100/100, Δ is 90-99 /
100 and × are 89 or less / 100.

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[Procedure amendment]

[Submission date] March 22, 2000 (200.3.2)
2)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Embedded image General formula (1) (R ₁ represents —CHO, —CH ₂ OH, or —COO ⁻ X ⁺ ,
X ⁺ represents a metal ion, an alkyl ammonium ion or a sulfonium ion, or an ammonium ion. )

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4J038 BA041 BA081 CA041 CC041 CD021 CD091 CF031 CG001 DA131 DB001 DD001 DG001 JA44 JA45 JA46 JA48 NA03 PC02

Claims (5)

[Claims] 1. A coating composition comprising a gluconic acid derivative salt represented by the general formula (1). Embedded image General formula (1) (R ₁ represents —CHO, —CH ₂ OH, or —COO ⁻ X ⁺ ,
X ⁺ represents a metal ion, an alkyl ammonium ion or a sulfonium ion, or an ammonium ion. ) 2. In the general formula (1), R ₁ is —CH ₂ O
The coating composition according to claim 1, wherein H and X ⁺ are an alkali metal ion, an alkaline earth metal ion, a transition metal ion or an amphoteric metal ion. 3. The coating composition according to claim 1, wherein in the general formula (1), X ⁺ is a Na ion, a K ion, a Mg ion or a Ca ion. 4. The coating composition according to claim 1, wherein in the general formula (1), X ⁺ is Fe ion, Al ion or Zn ion. 5. The coating composition according to claim 1, wherein in the general formula (1), X ⁺ is a quaternary alkylammonium ion.