JPH10219146A - Production of aminoquinone-containing polyisocyanate for corrosion-resistant coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a polyisocyanate for corrosion- resistant coating materials which is excellent in corrosion resistance without using a rustproof pigment or a rustproof agent. SOLUTION: (1) In producing a polyisocyanate by reacting an org. polyisocyanate with an active hydrogen compd., a hydroxylated aminoquinone is used as at least a part of the active hydrogen compd. (2) In producing a polyisocyanate by reacting an org. polyisocyanate with an active hydrogen compd., a hydroxylated aminoquinone is used as at least a part of the active hydrogen compd. and the resultant polyisocyanate is converted into an isocyanurate and/or a uretedione.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an aminoquinone-containing polyisocyanate for a corrosion-resistant paint.

[0002]

2. Description of the Related Art Heretofore, as a metal corrosion-resistant paint, a paint containing a rust preventive pigment or a rust inhibitor has been used. Japanese Unexamined Patent Publication (Kokai) No. 53-126039 discloses a primary rust preventive coating composition containing a phenoxy resin or a polyurethane resin containing at least one selected from a phosphate pigment and barium metaborate. However, it is well known that lead-based rust preventive pigments such as lead red, lead suboxide, cyanamide lead, calcium plumbate and the like are harmful to the human body. Also,
The rust preventives such as phosphate pigments described in JP-A-53-126039 and widely used chromate, nitrite, organic carboxylate, etc. are decomposed by the rust preventive itself.
It ionizes and passivates the metal to show a rust-preventive effect, but the ions generated after this decomposition may damage the resin, thus reducing the durability, weather resistance and abrasion resistance of the coating film. There is.

[0003]

For this reason, rust-inhibiting pigments such as lead red which are harmful to the human body and paints which do not use rust-inhibiting agents which adversely affect the coating film have been studied. At present, there is no paint with sufficient performance.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to solve such problems, and as a result, the polyisocyanate obtained by the production method of introducing aminoquinone has corrosion resistance. The inventors have found that the paint using this polyisocyanate has excellent corrosion resistance, sufficient coating film durability, and the like, and have completed the present invention.

That is, the present invention includes the following (1) and (2). (1) An organic polyisocyanate, a polyisocyanate obtained by reacting an active hydrogen group-containing compound,
A method for producing an aminoquinone-containing polyisocyanate for a corrosion-resistant paint, wherein a part or all of the active hydrogen group-containing compound is a hydroxyl group-containing aminoquinone.

(2) In the polyisocyanate obtained by reacting an organic polyisocyanate and an active hydrogen group-containing compound, a part or all of the active hydrogen group-containing compound is a hydroxyl group-containing aminoquinone, and the obtained polyisocyanate A method for producing an aminoquinone-containing polyisocyanate for a corrosion-resistant paint, wherein the isocyanurate and / or uretdione is produced from

[0007]

DETAILED DESCRIPTION OF THE INVENTION The organic polyisocyanate used in the present invention is, for example, 2,4-tolylene diisocyanate (hereinafter abbreviated as 2,4-TDI),
2,6-TDI, 4,4'-diphenylmethane diisocyanate (hereinafter abbreviated as 4,4'-MDI), 2,
4′-MDI, 2,2′-MDI, 1,5-naphthylene diisocyanate, 1,4-naphthylene diisocyanate, p-phenylene diisocyanate, m-phenylene diisocyanate, o-xylylene diisocyanate,
m-xylylene diisocyanate, p-xylylene diisocyanate, tetramethyl xylylene diisocyanate, 4,4'-diphenyl ether diisocyanate,
2-nitrodiphenyl-4,4'-diisocyanate,
2,2'-diphenylpropane-4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane-4,
Aromatic diisocyanates such as 4'-diisocyanate, 4,4'-diphenylpropane diisocyanate, 3,3'-dimethoxydiphenyl-4,4'-diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (hereinafter abbreviated as HDI); Aliphatic diisocyanate such as pentamethylene diisocyanate, 2-methyl-1,5-pentane diisocyanate, 3-methyl-1,5-pentane diisocyanate, lysine diisocyanate, isophorone diisocyanate (hereinafter abbreviated as IPDI), hydrogenated tolylene diisocyanate , Hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate (hereinafter H ₆
XDI), alicyclic diisocyanates such as hydrogenated tetramethylxylylene diisocyanate and cyclohexyl diisocyanate, and mixtures of two or more thereof. Further, so-called polymeric type polyisocyanates such as polyphenylene polymethylene polyisocyanate (hereinafter abbreviated as polymeric MDI) and crude TDI can also be used. These organic polyisocyanates are adduct-modified, buret-modified, uretdione-modified, and uretimine-modified. Modified isocyanates such as isomers, isocyanurate modified products, carbodiimide modified products and the like may be used. Preferred organic polyisocyanates in the present invention, TDI, MDI, a polymeric MDI and modified isocyanates, in the case that requires weather resistance, HDI, IPDI, H ₆ XDI and modified isocyanates are preferred.

The hydroxyl group-containing aminoquinone used in the present invention is, specifically, 2,5-bis (N-methylol-N
-Methyl-amino) -1,4-benzoquinone (hereinafter M
EMQ), 2,5-bis (N-methylol-
N-ethyl-amino) -1,4-benzoquinone, 2,5
-Bis (N-methylol-N-phenyl-amino)-
1,4-benzoquinone, 2,5-bis (N-methylol-N-benzyl-amino) -1,4-benzoquinone,
2,5-bis (N-2-hydroxyethyl-N-methyl-amino) -1,4-benzoquinone (hereinafter abbreviated as HEMQ), 2,5-bis (N-2-hydroxyethyl-N-ethyl) -Amino) -1,4-benzoquinone, 2,
5-bis (N-2-hydroxyethyl-N-phenyl-
Amino) -1,4-benzoquinone, 2,5-bis (N-
2-hydroxyethyl-N-benzyl-amino) -1,
4-benzoquinone and the like.

The present invention also relates to a compound containing an active hydrogen group used in the ordinary polyurethane industry, specifically, a number average molecular weight of 300 to 10,000, preferably 500 to 10,000.
A high molecular weight polyol of 5,000 and a chain extender such as a low molecular weight polyol having a molecular weight of less than 300, a low molecular weight polyamine and a low molecular weight amino alcohol may be used in combination.

The high molecular polyol includes polyester polyol, polyether polyol, polycarbonate polyol, polyether ester polyol, polyolefin polyol and the like.
More than one kind may be used.

Examples of the polyester polyol include known phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, succinic acid, tartaric acid, oxalic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, curtaconic acid, Azelaic acid, sebacic acid succinic acid, adipic acid, sebacic acid, azelaic acid, 1,4-
Cyclohexyldicarboxylic acid, α-hydromuconic acid,
polycarboxylic acids such as β-hydromuconic acid, α-butyl-α-ethylglutaric acid, α, β-diethylsuccinic acid, maleic acid, fumaric acid, hemimelitic acid, trimellitic acid, pyromellitic acid, and benzophenonetetracarboxylic acid Or one or more of anhydrides and the like, ethylene glycol,
Diethylene glycol, dipropylene glycol, 1,
2-propanediol, 1,3-propanediol,
1,2-butanediol, 1,3-butanediol,
1,4-butanediol, 1,5-pentanediol,
1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, 1,9-nonanediol, neopentyl glycol (hereinafter referred to as NPG
), Diethylene glycol, dipropylene glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, ethylene oxide or propylene oxide adduct of bisphenol A, trimethylolpropane (hereinafter, referred to as
TMP), glycerin, hexanetriol, quadrol and other low molecular weight diols and low molecular weight triols. Further, there are lactone-based polyester polyols obtained by ring-opening polymerization of cyclic ester (so-called lactone) monomers such as ε-caprolactone, alkyl-substituted ε-caprolactone, δ-valerolactone, and alkyl-substituted δ-valerolactone.

Examples of the polyether polyol include homopolymers and copolymers of epoxides such as ethylene oxide, propylene oxide, and tetrahydrofuran, and cyclic ethers.

The polycarbonate polyol is obtained from a deethanolation reaction or a phenol reaction of at least one of low molecular diols and low molecular triols, which are the above-mentioned polyester polyol sources, with diethyl carbonate and diphenyl carbonate.

As the polyether / ester polyol, there is a copolyol obtained from the above-mentioned polyether polyol and the above-mentioned dicarboxylic acid. In addition, there are those obtained by the reaction of the above-mentioned polyester or polycarbonate with epoxide or cyclic ether.

Examples of the polyolefin polyol include hydroxyl-containing polybutadiene, hydrogenated hydroxyl-containing polybutadiene, hydroxyl-containing polyisoprene, hydrogenated hydroxyl-containing polyisoprene, and hydroxyl-containing chlorinated polypropylene.

A known resin such as a urea resin, an acrylic resin, a melamine resin, an epoxy resin, a polyester resin, or a polyvinyl alcohol, which contains two or more active hydrogen groups and has a number average molecular weight of 300 to 10,000, Those having a molecular weight of preferably from 500 to 5,000 can be used as the polymer polyol.

As the low molecular polyol as the chain extender, there is the low molecular polyol of the above-mentioned polyester polyol source, and these may be used alone or in combination of two or more.

As the low molecular weight polyamine, there are diamines such as tetramethylenediamine, hexamethylenediamine, isophoronediamine and the like, and triamines such as diethylenetriamine and the like.

Examples of the amino alcohol include monoethanolamine, diethanolamine, triethanolamine, and aniline ethylene oxide and propylene oxide adducts.

As the reaction method of the aminoquinone-containing polyisocyanate of the present invention, a known method is used. For example,
Reaction of an active hydrogen group-containing compound with an organic polyisocyanate under conditions of an excess of isocyanate groups, specifically, when the R value (total isocyanate groups / active hydrogen groups) exceeds 1.0 to 100, preferably 1.1 to 50 Obtained. The reaction temperature at this time is 10 to 120 ° C, preferably 30 to 10 ° C.
0 ° C. Further, the free isocyanate compound may be removed after the reaction. At this time, if necessary, a tertiary amine catalyst such as triethylamine or an organic metal catalyst such as dibutyltin dilaurate may be used.

Further, the above-mentioned polyisocyanate can be further subjected to isocyanuration and / or uretdionation. Isocyanuration and / or uretdionation reactions are known. For example, the reaction temperature at this time is 10 to 120 ° C., preferably 30 to 90 ° C., and the reaction catalyst at this time is a fatty acid such as triethylphosphine. And aromatic phosphines such as tribenzylphosphine. The method for terminating the isocyanuration and / or uretdionation reaction is possible by adding phosphoric acid, sulfur, or the like to inactivate the catalyst.

Further, in order to increase the number of functional groups (to increase the crosslink density), an allophanate-forming reaction or a buret-forming reaction may be carried out as necessary.

The aminoquinone-containing polyisocyanate of the present invention may contain an organic solvent, if necessary. This organic solvent is an aromatic solvent such as toluene, xylene, pentane, hexane, an aliphatic hydrocarbon solvent such as octane, cyclopentane, cyclohexane, an alicyclic hydrocarbon solvent such as methylcyclohexane, acetone,
Ketone solvents such as methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diisobutyl ketone, cyclohexanone, methyl cyclohexanone, ether solvents such as diethyl ether, 1,4-dioxane, tetrahydrofuran, ethylene glycol dimethyl ether, ethylene glycol monomethyl ether acetate, propylene Glycol dimethyl ether, propylene glycol monomethyl ether acetate (hereinafter P
There is no particular limitation as long as it is inert to isocyanate groups such as cellosolve solvents such as GMAC), ester solvents such as ethyl acetate and butyl acetate, and dimethylformamide, dimethylacetamide and N-methylpyrrolidone.

The above-mentioned organic solvent may be charged before the synthesis of the aminoquinone-containing polyisocyanate, or may be charged after the synthesis.

The aminoquinone-containing polyisocyanate according to the present invention has an NCO content of 1 to 30% by weight, preferably 3 to 25% by weight, as solids. When the NCO content is less than 1% by weight, the physical properties of the coating film do not exhibit sufficient strength. If it exceeds 30% by weight, the hydroxyl group-containing aminoquinone is not sufficiently introduced into the polyisocyanate, and the durability of the coating film deteriorates.

The aminoquinone-containing polyisocyanate according to the present invention can be used as a curing agent for a corrosion-resistant paint using a resin containing an active hydrogen group. The compounding ratio is such that all isocyanate groups / total active hydrogen groups = 1/9 to 9/1, preferably 2/8 to 8/2.

The aminoquinone-containing polyisocyanate according to the present invention itself can be used as a corrosion-resistant paint, and can be a pigment / dye, a solvent, a thixotropic agent, an antioxidant, an ultraviolet absorber, an antifoaming agent, a thickener, a dispersant, An additive such as a surfactant may be blended. These additives can be compounded by a known method, for example, using a ball mill, a sand grind mill or the like. The obtained corrosion-resistant paint is applied using a brush, a spray or the like.

In the anticorrosion paint containing aminoquinone-containing polyisocyanate according to the present invention as a main component of the varnish, a curing agent may be added immediately before application. Specific examples of the curing agent include low molecular weight polyols such as ethylene glycol and glycerin used as chain extenders, and polyamines such as isophorone diamine and diethylene triamine.

[0029]

According to the present invention, it has become possible to provide an aminoquinone-containing polyisocyanate for a corrosion-resistant paint. In addition, the anticorrosion paint using the aminoquinone-containing polyisocyanate provided by the present invention is excellent without using a rust inhibitor pigment such as lead red which is harmful to the human body, or a rust inhibitor which adversely affects the coating film. It showed corrosion resistance and the durability of the coating film was found to be very excellent.

[0030]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In addition,
In the examples, “parts” indicates “parts by weight” and “%” indicates “% by weight”.

[Synthesis of Aminoquinone-Containing Polyisocyanate Composition] Example 1 100 parts of 2,4-TDI and 5 parts of toluene were placed in a reactor equipped with a stirrer, a cooling pipe, a thermometer and a nitrogen gas introducing pipe.
0 parts were charged and heated to 40 ° C. Then, MEMQ is changed to 6
Five parts were charged and reacted at 80 ° C. for 3 hours to obtain aminoquinone-containing polyisocyanate AQPI-A. AQP
The NCO content of IA is 11.2%, and the solid content is 76.
7%.

Example 2 A carbodiimide-modified MDI was used in the same apparatus as in Example 1.
(Japan Polyurethane Industrial Product Name: Millionate MT
L NCO content = 29.0%), 100 parts
Warmed to 0 ° C. Next, 25 parts of MEMQ were charged, and
The reaction was carried out at 2 ° C. for 2 hours. Thereafter, 5 parts of TMP was charged and further reacted at 80 ° C. for 3 hours to obtain aminoquinone-containing polyisocyanate AQPI-B. AQPI-
The NCO content of B was 12.8%.

Example 3 In the same apparatus as in Example 1, polymeric MDI and MDI
(A product of Nippon Polyurethane Industry, trade name: Millionate MR-200, NCO content = 30.8%)
0 parts and 25 parts of butyl acetate were charged and heated to 40 ° C.
Next, 25 parts of HEMQ was charged and reacted at 80 ° C. for 3 hours to obtain aminoquinone-containing polyisocyanate AQPI.
-C was obtained. The NCO content of AQPI-C is 15.0
%, And the solid content was 83.3%.

Example 4 In the same apparatus as in Example 1, an isocyanurate-modified HDI (trade name: Coronate H, manufactured by Nippon Polyurethane Industry Co., Ltd.)
X NCO content = 21.3%), 100 parts
Warmed to 0 ° C. Next, 20 parts of HEMQ was charged and 8
The reaction was carried out at 0 ° C. for 3 hours to obtain aminoquinone-containing polyisocyanate AQPI-D. AQPI-D NCO
The content was 12.2%.

Example 5 The same apparatus as in Example 1 was charged with 100 parts of H ₆ XDI and heated to 40 ° C. Then 4 parts of HEMQ, NPG
Was charged at 80 ° C. for 2 hours to obtain a reaction product liquid (1) having an NCO content of 40.0%. Next, uretdione and 0.5 part of tributylphosphine as an isocyanuration catalyst were charged into the reaction product liquid (1), and reacted at 70 ° C. for 6 hours with stirring. Then, 1.0 part of phosphoric acid was added to stop the uretdione and isocyanuration reaction, to obtain a reaction product liquid (2). From the reaction product solution (2), unreacted H ₆ XDI was added at 140 ° C. and 0.1 mL
Removal by thin film distillation at 01 Torr gave aminoquinone-containing polyisocyanate AQPI-E. AQPI
The NCO content of -E was 22.4%. Note that A
The QPI-E was a FT-IR and C ¹³ -NMR measurement, an isocyanate group, uretdione group, and the presence of isocyanurate groups was confirmed.

Example 6 In the same apparatus as in Example 1, 93 parts of butyl acetate and IPD
100 parts of I was charged and heated to 40 ° C. Then MEM
34 parts of Q, 75 parts of poly (oxytetramethylene) diol having a number average molecular weight of 1,000 (hereinafter abbreviated as PTMG-1000) and 8 parts of NPG, and reacted at 80 ° C. for 4 hours to give aminoquinone A polyisocyanate containing AQPI-F was obtained. AQPI-F had an NCO content of 4.0% and a solids content of 70.0%.

Table 1 shows the raw material ratios used in Examples 1 to 6 and the synthesis results.

[0038]

[Table 1]

[Evaluation of anticorrosion paint]

APPLICATION EXAMPLE 1 Epicron H-201-60BT (epoxy polyol, manufactured by Dainippon Ink and Chemicals, Inc.) AQPI-A, a solvent and a thixotropic agent were blended in the following proportions to prepare a corrosion-resistant paint sample P-1. . After blending each raw material, it was dispersed for 2 hours using a paint shaker. The formulation is shown below. Epicron H-201-60BT 100.0 parts AQPI-A 81.5 parts Toluene 21.0 parts Ethyl acetate 21.0 parts Butyl acetate 21.0 parts PGMAC 21.0 parts Surface-treated calcium carbonate 2.0 parts

Application Examples 2 to 5 Corrosion-resistant paint samples P-2 to P-5 were prepared using AQPI-B to E according to the formulations shown in Table 2.

Application Example 6 An anticorrosion paint sample P-6 was prepared by mixing AQPI-F, a solvent, and a curing agent in the following proportions. After blending each raw material, it was dispersed for 2 hours using a paint shaker. The formulation is shown below. AQPI-F 100.0 parts Glycerin 3.0 parts Toluene 20.0 parts

Comparative Examples 1 to 3 Corrosion-resistant paint samples P-7 to 9 were prepared using Millionate MTL, Coronate L, and Coronate HX (all manufactured by Nippon Polyurethane Industry Co., Ltd., polyisocyanate) with the formulations shown in Table 2. did.

[0044]

[Table 2]

The obtained anticorrosion paint samples P-1 to P-9 were dried on a mild steel plate having a thickness of 1 mm using an applicator.
0 μm, dried at 60 ° C. for 30 minutes,
Thereafter, curing was performed at 100 ° C. for 24 hours. The obtained test pieces were evaluated by a pencil hardness test and a cross-cut peel test described in JIS K-5400. Further, using another test piece, salt water was sprayed according to the method described in JIS K-5400, and a pencil hardness and a cross-cut peeling test were similarly performed. Table 2 shows the evaluation results.

The coating film evaluation method is described below. Pencil hardness test: The pencil hardness specified in JIS S-6006 was extruded at an angle of 45 degrees and the highest hardness of the pencil that did not break the coating film was defined as the coating film hardness. Cross-cut peeling test: 100 square 1 mm square cuts were made using a cutter knife with a cutter guide on the coating film, a cellophane tape was pressed from above, and then instantaneously peeled off. I saw the peeling condition. ：: less than 10% peeled △: 10% or more to less than 50% peeled ×: 50% or more peeled

[0047]

[Table 3]

Claims (2)

[Claims] 1. An aminoquinone for a corrosion-resistant paint, wherein a part or all of the active hydrogen group-containing compound is a hydroxyl group-containing aminoquinone in an organic polyisocyanate and a polyisocyanate obtained by reacting an active hydrogen group-containing compound. Method for producing polyisocyanate. 2. An organic polyisocyanate and a polyisocyanate obtained by reacting an active hydrogen group-containing compound, wherein a part or all of the active hydrogen group-containing compound is a hydroxyl group-containing aminoquinone. A method for producing an aminoquinone-containing polyisocyanate for a corrosion-resistant coating, which comprises isocyanurating and / or uretdione.