JPS60127373A - Coating composition - Google Patents

Abstract

PURPOSE:To provide a coating composition for glass, etc., storable for a long period without causing thickening and gelling, etc., by compounding a synthetic hydroxyl-containing polymer with a hardener comprising an alkoxide of a metal selected from titanium, etc., and an organic solvent containing more than a specific amount of an alcohol. CONSTITUTION:The objective composition can be produced by compounding (A) a hydroxyl-containing polymer with (B) an alkoxide of a metal selected from titanium, zirconium, silicon and aluminum (e.g. alkoxide mixture containing 1- 12C alkoxide) and (C) an organic solvent containing >=5wt% alcohol (e.g. 1-8C alcohol). The amount of the alkoxyl group of the metal alkoxide is preferably 0.1-10 equivalent per 1mol of the hydroxyl group of the compound A. EFFECT:The composition can be applied easily because it forms a strong three- dimensional network structure at room temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to coating compositions, and more particularly to cold-curable coating compositions.

The paint is applied in a liquid state, loses its flowability and tackiness upon drying, and forms a coating film using various forming machines. Although there are some paints that form coating films by volatilization drying, cooling drying, or oxidative polymerization, coating films formed by condensation generally exhibit superior properties, so the number of coatings equipped with such drying mechanisms is increasing. ing.

One method for polycondensation is heating, in other words baking and drying, but this method requires a heating device and is difficult to carry out on-site. There is a demand for paints that can be cured. Room-temperature curing paints include two-component paints that are used by mixing curing agent components such as incyanate immediately before use, and paints that react and condense in the presence of moisture, or that cause catalytic effects in the presence of moisture. There are moisture-curing types that cure with water, and one-component radiation-polymerizing types that generate radicals and polymerize by irradiation with radiation such as r-rays, electron beams, and ultraviolet rays. Two-component room-temperature curing paints can form strong coatings, but their major disadvantages are that they have a short pot life after mixing with a curing agent and are complicated to prepare each time they are used. Furthermore, the one-component room-temperature curing paint for the moisture curing section has a small curing reaction and a small curing density, and cannot form a sufficiently tough coating film. Furthermore, radiation polymerization type paints have the disadvantage that they require a large amount of equipment and are difficult to apply on-site.

An object of the present invention is to provide a one-component room-temperature-curing coating composition that can form a coating film with a strong three-dimensional network structure and excellent properties at room temperature and can be stored for a long period of time.

The coating composition according to the invention contains a synthetic resin, a curing agent and an organic solvent. In the coating composition, the synthetic resin is a polymer having hydroxyl groups, the curing agent is an alkoxide of a metal selected from the group consisting of titanium, zirconium, silicon, and aluminum, and the organic solvent is
A coating composition characterized by containing 2% or more of alcohol.

In a preferred embodiment of the coating composition according to the present invention, the alkoxyl group of the metal alkoxide has 1 to 1 carbon atoms.
2, more preferably 3 to 8, and in another preferred embodiment, the amount of the metal alkoxide relative to the synthetic resin is 1 mole of the alkoxyl group of the metal alkoxide per 1 mole of the hydroxyl group of the nuclear synthesis buffing fat. equivalent is 0.1-1
0, more preferably 0.5 to 5.0.

Another preferred embodiment of the coating composition according to the present invention is that the alcohol content of the organic solvent is 10 or more, and in another preferred embodiment, the alcohol has 1 to 8 carbon atoms, more preferably 1 to 8 carbon atoms. 4 alcohol.

In yet another preferred embodiment 11M of the coating composition according to the present invention, the synthetic resin is composed of an alkyd resin, a phenolic resin, an epoxy resin, a melamine resin, a polyether resin, an acrylic resin, a butyral resin, a silicone resin, and a fluororesin. It is one type or a combination of multiple types selected from various crops.

Examples of the polymer having hydroxyl groups in the composition of the present invention include the following synthetic resins.

(1) An alkyd resin which is a condensation polymer of the nominal γ alcohol of glycerin and diglycerol hμ and a polybasic acid such as 7-talic anhydride and inphthalic acid.

(2) Phenolic resin A novolak or resol resin that is formed by a condensation reaction of phenol and formaldehyde under an acid or alkali catalyst.

(3) An epoxy resin that is a condensation reaction product of a polyhydric alcohol such as bisphenol A and a chlorohydrin such as chlorohydrin.

A melamine resin made by modifying melamine with alcohol (such as n-butanol) and condensing it with formaldehyde.

(5) A polyol-based polymer obtained by adding and polymerizing an alkylene oxide such as propylene oxide to a polyhydric alcohol such as glycerin or sucrose.

(6) Acrylic resin which is a polymer of acrylic acid ester containing hydroxyfur group-containing acrylate or methacrylate such as hydroxyethyl acrylate as an essential component.

(7) Butyral resins, silicone resins, -fluororesins containing hydroxyl foundations.

These synthetic resins can be used alone or in combination.

To describe the manufacturing method of these synthetic resins using an example of 1.2, 2-hydroxyethyl acrylate) 10.2
An acrylic resin having a j9oH value of 50 is obtained by radical polymerizing mol and 89.2 mol of ethyl acrylate. In addition, 17.2 moles of glycerin and 8 moles of 7-talic anhydride
oHHIO2 alkyd resin is obtained by condensation polymerization of 2.8 mol.

Fluororesins generally have excellent properties as paints. Therefore, when a fluorine resin contains a hydroxyl group and is used as a synthetic resin raw material for the coating composition of the present invention, a particularly useful coating composition can be obtained. An example of 1.2 will be given regarding the method for producing a fluororesin having a hydroxyl group.

By copolymerizing fluoroolefins such as detrafluoroethylene and chlorotrifluoroethylene with vinyl alcohol, hydroxyalkyl vinyl ether, or hydroxyalkyloxyalkyl vinyl ether,
A fluororesin containing hydroxyl groups is obtained which can be used as a raw material for a coating composition containing 1 pl of wood powder.

Example 1. 0F2=OF, / OH,=OH-0H,0
H35, 1 mol 64.9 mol Example 2゜ 0F2=OFz l 0H2=OH-0=04
11@0H51 mol 49 mol Example 3. 0Ft =OF2/ 0H2=OHCH2-0
Hydrolyzate example 4 of 00H31 57.2 mol 42.8 mol 0. OF? =OF, / 0H2=OH-0-0-
0H31 29.5 moles 70.5 moles of hydrolyzate Furthermore, co-condensation of polyfunctional fluorine-containing compounds containing hydroxyl groups such as the following, and co-condensation of epoxy compounds such as glycidol and polyfunctional fluorine-containing compounds. Also, a fluororesin containing hydroxyl groups can be obtained.

The composition of the present invention contains a metal alkoxide selected from the group consisting of titanium, zirconium, silicon and aluminum as a hardening agent. It has been known for a long time that these metal alkoxides undergo a crosslinking reaction with polymer 00H groups, and it is also known that di-1-propoxy bis(
T1 chelate compounds such as acetylacetone) titanate and di-n-butoxy bis(triethanolamine) titanate are conventionally used as crosslinking agents in paints. Furthermore, it is also known that the Kir-1 compound of Zr, A1 can be used in much the same manner.

However, these chelate compounds react more slowly than alkoxides, may corrode the objects to be coated, such as tin cans, and have drawbacks such as coloring the coating composition. On the other hand, although alkoxides of these metals react quickly, it has been known that they tend to gel the coating composition. In the composition of the present invention, gelation is achieved by using a large amount of alcohol as a solvent, as will be detailed later.

The alkoxyl group of the metal alkoxide in the composition of the present invention has 1 to 12 carbon atoms, preferably F13 to 8 carbon atoms. As an example of titanium alkoxide, Ti(0・i-
0++H7)4r Ti(0・n-04Ho)41Tt
[o ca2ca(o, )! , )04H,']4 and the like.

Similar properties can be mentioned for zirconium alkoxide. As an example of aluminum alkoxide, A1(0・i−0,H,c).

(i (4H70)2A1(sea-04HeO)+
(sea-04HgO)3A1 etc. are mentioned. An example of silicone alkoxide is aH, 51 (o・n 0
4Hg)B+ 0H3S1(0'10:1H7)3 etc. It is desirable that the monovalence of the metal forming the alkoxide is high; alkoxides of alkali metals and alkaline earth metals have poor water resistance, while metals such as iron are difficult to form into alkoxides.

The metal alkoxide in the composition of the present invention has a molar equivalent of alkoxyl groups of this gold rice alkoxide of 0.1 to 10, preferably 0.5 to 5.0 per mole of hydroxyl groups of the synthetic resin. The amount is assumed to be . The content of hydroxyl groups in synthetic resin is the hydroxyl value (OH value)
Indicated by The hydroxyl value (OH value) is the q number of KOH required to neutralize the acetic acid liberated by hydrolyzing the acetylated product obtained from the organic substance 12. Therefore,
By dividing the 08 value of the synthetic resin by 56108 lv (KOH molecule), the number of moles of OH in the synthetic resin lv can be determined. - Since the metal alkoxide used generally has a clear structure, the molar equivalent of the alkoxyl group can be easily calculated.

For example, OH value 600 synthetic resin 1f fi 60156
108 ni 0. It contains 107 moles of OHi. Ti(004H*)4 (molecular fit
340), this 1g contains 4/340=
It will contain 0.0118 moles of alkoxyl groups.

Therefore, the molar equivalent of alkoxyl groups per mole of hydroxyl groups in the synthetic resin is 0.1.0.5. 5. Q.

The amount of T1(0○4 Hll)4 that is 10 is resin 12
0.0907F, 0.4535f, 4 respectively for
．． 535f.

It is 9.07f.

One of the most important features of the composition of the present invention is that the organic solvent contains 5% or more of alcohol. Metal alkoxides such as Ti and ZrI sL Ax easily react with polymers having 0E groups at room temperature, but if a low molecular weight alcohol of 5 or more is present in the solvent, the metal alkoxides and polymers will react with each other during storage. It has been found that gelation caused by this reaction can be suppressed. Moreover, when the alcohol as a solvent evaporates after inoculation, the metal alkoxide reacts with the polymer having 0H groups, forming a strong three-dimensional network structure at linear temperature. The alcohol content of the solvent is preferably as high as possible without impairing the solubility of the synthetic &i fat, and is preferably 10 or more. The alcohol preferably has 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms. Organic solvents used together with alcohol include esters and ketones.

Almost all solvents, including aromatic ones, can be selected freely, taking into consideration paintability and other factors.

Next, an example will be described.

Example 1 Tetrafluoroethylene, inbutyl vinyl ether, and hydroxybutyl vinyl ether 50:40:10
A fluororesin having 40,000 molecular ruts and OHHCO2 hydroxyl i' was obtained. This fluororesin 501 was dissolved in an organic solvent consisting of 10 ft of tetrabutoxy titanium, 50 g of butanol, and xylene 502,
Clear coating film of the coating composition according to the invention
] Manufactured. Although this composition was kept at a temperature of 2 for 3 months, no thickening or gelling phenomena were observed.

This composition was applied to an alodine-treated aluminum plate having a thickness of 0.8 V5 using an applicator, and left to stand for 3 days to form a clear coating film.

The results of measuring the properties of the coating film were very good as shown in Table 1. This measurement method was based on J Engineering ElK54 [1.

Table 1 Example 2 Acrylic resin (acrylic polyol, trade name Orester Q-161-45 manufactured by Mitsui Toatsu KK → (on price) 00
LI Xylene 1009 n-butanol 1002 Tetrain propoxy titanium 259 Clearpheno was prepared from the above raw materials.

Even when this pheno was left for 3 months, there was no change such as thickening or gelation. This pheno was applied onto a glass plate with an applicator, and after being left at room temperature for 3 days, the physical properties of the coating film were measured.The lead hardness was HB, and the Kijiroll Love Test was 20.
Passed 0 times.

Examples 3 to 6 Clear phenos were prepared by using the same amounts of the fluororesin and organic solvent used in Example 1 and changing only the curing agent as follows. Example 3 Tetrabutoxyzirconium 25vl 4
Methyltrimethoxysilane 10F# 5 Triinpropoxyaluminum 1 (1〃 6 Tetrabutoxytitanium 15F) There was no change such as thickening or gelation for 3 months for each clear coat. When painted on aluminum and glass plates. The physical properties of the coating film were measured and the results are shown in Table 2.

Table 2 Example 7 Alkyd resin (trade name Burnock D-120-50)
(OHHSO310(1 xylene 1009 methanol 100f tetra(2ethylhexyloxy)titanium 301) Clearpheno was prepared using the above raw materials.

The fact that there was no change during storage was the same as in Examples 1 to 6.

This pheno was applied onto a glass plate with an applicator, left at room temperature for 5 days, and the physical properties of the resulting transparent coating film were measured; it had a lead white hardness of HB and passed the Kijiroll Love Test 50 times. .

Comparative Example 1 When Clearpheno was IMm'd using only xylene (100F) without containing butanol as the solvent in Example 1, the viscosity increased within a few minutes of lO, gelation occurred, and it could no longer be used as a paint.

Comparative Example 2 In Example 1, without using tetrabutoxytitanium,
When pheno was prepared and applied using only fluororesin, butanol, and xylene, only an uncured coating film with a lead quality of 2B or less was obtained in the Kijiroll Rub Test 10 times or less.

〔Effect of the invention〕

As described above, the coating composition i of the present invention is thickened.

It can be stored for a long time without causing changes such as gelation,
When painting, by drying at room temperature without adding any new additives, the reaction between the metal alkoxide and the polymer with OH groups begins, forming a strong three-dimensional network structure. Therefore, the coating work can be easily performed and a coating film with excellent properties can be obtained. Therefore, the coated composition according to the present invention has extremely high industrial utility value.

Daisara Jinnai 1) Akira Agent Hagihara U6-・

Claims (6)

[Claims] (1) In a coating composition containing a synthetic resin, a curing agent, and an organic solvent, the synthetic resin is a polymer having hydroxyl groups, and the curing agent is a metal selected from the group consisting of titanium, zirconium, silicon, and aluminum. alkoxide, and the organic solvent contains 5 parts by weight or more of alcohol. (2) The coating composition according to claim 1, wherein the alkoxyl group of the Kanahashi alkoxide has 1 to 12 carbon atoms, preferably 3 to 8 carbon atoms. (3) The amount of metal alkoxide relative to the synthetic resin is
3. The coating composition according to claim 1, wherein the amount of the metal alkoxide is such that the molar equivalent of the alkoxyl group of the metal alkoxide is 01 to 10 per mole of the hydroxyl group of the synthetic resin. (4) The composition according to claim 1, wherein the organic solvent has an alcohol content of 1 ton or more, 2. (5) The coating composition according to item 1 or 4, in which the alcohol is an alcohol having 1 to 8 carbon atoms. (6) The synthetic resin is one or more selected from the group consisting of alkyd resin, phenol resin, epoxy resin, melamine resin, polyether resin, acrylic resin, butyral resin, silicone resin, and fluororesin.
The coating composition of claim 1ffi which is a combination.