JPS58176209A - Ultraviolet ray-curable unsaturated polyester resin composition - Google Patents

Abstract

PURPOSE:An ultraviolet ray-curable resin composition capable of providing paint films or moldings excellent in cracking resistance and surface grindability, containing a specified unsaturated polyester, an allyl ether group-containing unsaturated polyester and a polymerizable monomer. CONSTITUTION:A resin composition containing (A) an unsaturated polyester prepared by effecting an addition reaction between an unsaturated polyester having carboxyl groups on molecular terminals and an unsaturated monoglycidyl compound, (B) an allyl ether group-containing unsaturated polyester and (C) a polymerizable monomer. The amount of the allyl ether groups in the unsaturated polyester (B) depends usually on that of the allyl ether group-containing compound used, and is preferably 8-25wt% based on the unsaturated polyester (B). The mixing ratio between the unsaturated polyesters (A) and (B) is preferably 8:2-5.5. The weight ratio of the polymerizable monomer to the sum of the unsaturated polyesters (A) and (B) is preferably 2:8-6:4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultraviolet curable paint-coated polyester resin composition that can provide coatings, molded articles, etc. with excellent crack resistance and surface abrasiveness.

Recently, there has been a growing demand for higher performance paints that are suitable for resource and energy conservation due to social needs. As such a paint, an ultraviolet curable paint is used because of its advantages such as (1) fast curing, (2) low energy cost, and (3) non-polluting property. For example, in wood painting, UV-curable paints obtained by adding photosensitizers to air-curable unsaturated polyester resins are used as intermediate coatings, so-called sanding paints, which are the most commonly used intermediate coatings. However, when such paints are cured by irradiation with ultraviolet rays, their surface drying properties are insufficient (and their abrasiveness is poor, and when they are completely cured, the internal distortion of the paint film is large, resulting in cracks). The occurrence of these cracks is generally due to the fact that in the curing mechanism, ultraviolet curing has an extremely rapid generation rate of radicals ( It is presumed that this is due to the fact that it cures quickly and inevitably generates a large amount of internal strain.

In particular, advances in photosensitizers and light irradiation equipment have made it possible to increase the curing speed and improve the quality of the hardening process, but on the other hand, the problem of cracks as mentioned above has become an even bigger problem. Therefore, improvement is desired.In order to improve this drawback, (11) a method of lowering the crosslinking density of the cured product to soften the coating film, (2) a method of softening the coating film by reducing the crosslinking density of the cured product; The main method used has been to introduce a skeleton. However, these methods not only do not sufficiently improve cracks, but also reduce the hardness and chemical resistance of the cured coating film, worsen surface drying properties, and cause polishing problems. It has defects that adversely affect workability, such as being unable to do so.

In particular, the inventors have discovered that the coating required for sanding paint
! As a result of extensive research into a resin composition with excellent crack resistance and surface abrasion rigidity without deteriorating its properties and workability, we found an unsaturated resin composition made by addition-reacting an unsaturated glycidyl compound to an unsaturated polyester containing terminal carboxyl groups. By mixing a polyester resin and an unsaturated polyester resin containing an allyl ether group, an ultraviolet curable unsaturated polyester resin composition with excellent crack resistance and surface abrasiveness was discovered, and the present invention was completed. Ta.

That is, the present invention relates to an unsaturated polyester 4A) obtained by addition-reacting an unsaturated monoglycidyl compound to an unsaturated polyester containing a carboxyl group at the molecular end, and an unsaturated polyester/L containing an allyl ether group (Bl and , and a polymerizable monomer (C).

Since the composition of the present invention contains both polyester components (A) and (B), it clearly shows unexpected improvements in physical properties, particularly crack resistance and surface abrasiveness, that is, a synergistic effect.

The "unsaturated polyester obtained by adding an unsaturated monoglycidyl compound to an unsaturated polyester containing a carboxyl group at the end of the molecule" constituting the composition of the present invention is, for example, an unsaturated polybasic acid or its anhydride. An esterified polymer obtained by reacting an acid component containing an acid component, optionally a saturated polyhydrochloric acid or its anhydride, and an alcohol component such that the acid component is in excess in equivalent ratio, that is, containing a carboxyl group at the molecular end. This refers to an unsaturated polyester obtained by adding an unsaturated glycidyl compound to an unsaturated polyester. In this case, the unsaturated polyester containing carboxyl groups at the molecular ends is preferably linear with carboxyl groups at both ends, but 50% or less, preferably 75% or less of one end of both ends is a hydroxyl group. Alternative unsaturated polyesters containing terminal carboxyl groups can also be used. Also, this polyester usually has an acid value of 25~
145. The unsaturated glycidyl compound, which is one of the components constituting this polyester, includes glycidyl esters of unsaturated basic acids such as acrylic acid and methacrylic acid, glycidyl acrylate, glycidyl methacrylate, etc., ar/lyl alcohol, methallyl alcohol, etc. Glycidyl ethers of unsaturated alcohols, such as allyl glycidyl ether, meta-allyl glycidyl ether, and other known and commonly used glycidyl ethers can be mentioned.

In addition, such unsaturated glycidyl compounds include α-, β-, such as glycidyl acrylate and glycidyl methacrylate.
Unsaturated unsaturated acid base acid cidyl esters are preferred. or,
Unsaturated polybasic acids or their anhydrides, which are essential components of unsaturated polyesters, include maleic acid, fumaric acid,
It is selected from known and commonly used α, β-, β-polybasic acids such as itaconic acid, citraconic acid, methaconic acid, chlorinated maleic acid, and their anhydrides. In addition, as the saturated polybasic acid or its anhydride that can be used in combination if necessary,
For example, phthalic acid, phthalic anhydride, tetrano-hydrophthalic anhydride, cis-3-methyl-4-cyclohexene-cis, cis-1,2-dicarboxylic anhydride, isophthalic acid, terephthalic acid, dimethylterephthalic acid, monochlorophthalic acid. Known and commonly used saturated acids such as dichlorophthalic acid, trichlorophthalic acid, het acid, tetrabromophthalic acid, monoclic acid, cono-phosphoric acid, adipic acid, glutaric acid, pimelic acid, trimellitic acid, pyromellitic acid, etc. Or its anhydride (preferably ester) can be used.

Preferably, compounds having idle running properties such as cis-3-methyl-4-cyclohexene-cis and cis-1,2-dicarboxylic anhydride are preferred.

Alcohol components of unsaturated polyester 8A) include ethylene glycol, diethylene glycol, triethylene glycol-A/, polyethylene glycol, propylene glycol, diethylene glycol, tripropylene glycol, polypropylene glycol, 1. ! l-7'
Tylene glycol, 2.3-7'f tylene glycol, 1
．． 4-7' ethylene glycol, neopentyl glycol, hexylene glycol, octyl glycol, trimethylol prono(glycerin, pentaerythritol,) 1-hydroquinone ethylene oxide or noropylene oxide adduct, hydrogenated bisphenol A,) Known and commonly used polyhydric alcohols such as lycyclodecane dimethylol can be mentioned.

The amount of the added unsaturated monoglycidyl compound in the unsaturated polyester AHAl is usually 5~! in the unsaturated polyester MA). 101 [amount%, preferably 10-15
An appropriate amount is t% by weight.

[Unsaturated polyester containing allyl ether group] constituting the composition of the present invention is usually an unsaturated polybasic acid or anhydride, and if necessary, an acid component containing a saturated polybasic acid or an anhydride thereof. and an alcohol component, and a compound that has a functional group that reacts with the carboxyl group of the acid component or the hydroxyl group of the alcohol component and also has an allyl ether group (hereinafter referred to as an allyl ether group-containing compound). are synonymous with each other. At this time, the allyl ether group-containing compound is simultaneously mixed with other components and subjected to the reaction.

As such allyl ether group-containing compounds, any known and commonly used compounds can be used, but typical examples include ethylene glycol monoallyl ether, diethylene glycol monoallyl ether, triethylene glycol monoallyl ether, and polyethylene glycol. Monoallyl ether, propylene glycol monoallyl ether, cyclopylene glycol monoallyl ether, tripropylene glycol monoallyl ether, polypropylene glycol monoallyl ether, 1,
2-Butylene glycol monoallyl ether, 1.3-
7' ethylene glycol monoallyl ether, hexylene glycol monoallyl ether, octylene glycol monoallyl ether, trimethylolpropane monoallyl ether, trimethylolpropane diallyl ether, glycerin monoallyl ether, glycerin diallyl ether, pentaerythritol monoallyl ether,
Allyl ether compounds of polyhydric alcohols such as pentaerythritol diallyl ether and pentaerythritol triallyl ether; allyl ether compounds having an oxirane ring such as allyl glycidyl ether; and the like.

Further, as the acid component and alcohol component which are the constituent components of the unsaturated polyester/L(B), the same ones as the acid component and alcohol component which constitute the unsaturated polyester base are used. In addition, -hydric alcohols, dicyclopentadiene or its derivatives, rosin or ester gums, oils and fats, etc. can also be used in combination.

The amount of allyl ether groups in unsaturated polyester/L(B) is usually specified by the amount of the allyl ether group-containing compound used, and specifically, the amount of allyl ether groups in unsaturated polyester/L(B) is specified by the amount of the allyl ether group-containing compound used.
(B) A suitable amount is 5 to 60% by weight, or 8 to 25% by weight.

As the above-mentioned "polymerizable monomer odor" which is another essential component constituting the composition of the present invention, any known and commonly used one can be used, but typical examples include styrene, α-methylstyrene, vinyltoluene, chlorstyrene, acrylic acid or methacrylic acid or their alkyl esters, acrylonitrile, vinyl acetate, allyl acetate, triallyl cyanurate, triallyl isocyanurate, acrylamide, diaseptone acrylamide, diallyl Examples include phthalates, among which styrene or methacrylic acid alkyl esters are preferred.

The blending ratio of unsaturated polyester/L (A) and (B) in the composition of the present invention is usually the former: the latter (weight ratio) of 9.
:1 to 6:7, preferably 8:2 to 5:5. or,
Polymerizable monomer, unsaturated polyester resin and 'fiB
) to the total amount (solid content ratio) is suitably 2:8 to 6:4.

When the composition of the present invention having the structure described above is cured by ultraviolet rays, a photosensitizing substance is added, and specific examples thereof include benzoin, benzoin methyl ether,
Benzine ethyl ether, benzyl, cyphenyl disulfide, tetramethyl-thiuram monosulfide, p-tert-butyltrichloroacetophenone, p
-tert-butyldichloroacetophenone, 2,2-
One or more types of known and commonly used compounds such as dimethoxy-2-phenylacetophenone can be used.

Furthermore, organometallic salts such as cobalt naphthenate and cobalt octenoate can be used in combination with the composition of the present invention as an aid for improving surface drying properties. Furthermore, for the composition of the present invention, other conventional unsaturated polyester resins, vinyl ester resins, vinyl urethane resins, vinyl ester urethane resins, polyisocyanates, and polyepoxides may be used depending on the purpose.

Acrylic resins, alkyd resins, urea resins, melamine resins, polyvinyl acetate, vinyl acetate copolymers, polydiene elastomers, saturated polyesters, saturated polyethers, nitrocellulose, cellulose-acetate butyrate, etc. Natural and synthetic polymeric substances such as cellulose derivatives and oils and fats such as linseed oil, tung oil, soybean oil, castor oil, and epoxidized oils; calcium carbonate, talc,
mica, clay, silica powder, colloidal silica,
Asbestos powder, barium sulfate, aluminum hydroxide,
Various fillers and a-materials such as zinc stearate, titanium white, zinc white, red iron oxide, or azo pigment; hydroquinone, benzoquinone, toluhydroquinone, p-tart-butylcatechol, 2,6-tert-butyl-4-methylphenol It is also possible to add polymerization inhibitors such as.

The composition of the present invention thus obtained is suitable not only for coating wood products such as furniture and musical instruments, but also for coating various substrates including metal coatings such as metal surf baits and top coats. It can also be used for FRP molding.

Next, the present invention will be explained in detail using reference examples, working examples, and comparative examples, but the present invention is not limited to these examples. In the following, all parts and percentages are based on weight unless otherwise specified.

Reference Example 1 [Preparation of unsaturated polyester tree IMA] Isophthalic acid (1 mol) and diethylene glycol (180 g (1.7 mol)) were heated at 215°C in an inert gas stream.
Intermediate-1 whose solid content has an acid value of 7 after heating and dehydration condensation with
I got it. Next, after cooling this intermediate-1 to 160°C, hydroquinone 0.029 and fumaric acid 11
6 g (1 mol) was added thereto, and the mixture was heated and reacted at 200° C. for 8 hours to obtain an unsaturated polyester.

Thereafter, this polyester was dissolved in 162 g of styrene to obtain Intermediate-2 having an acid value of 59. Next, 1.1 g of 2-methylimidazole and 86 g (α6 mol) of glycidyl methacrylate were added to this intermediate-2 to give 80
A ring-opening addition reaction was carried out at °C for 10 hours to obtain an unsaturated polyester resin having an acid value of 4 and a Gardner viscosity (hereinafter simply referred to as viscosity) xy. Hereinafter, this will be abbreviated as resin.

Reference Example 2 [Preparation of unsaturated polyester tree MB)] Maleic anhydride 19611 (2 mol) and diethylene glycol 159 g (15 mol) were mixed at 200 g in an inert gas stream.
Dehydration condensation was carried out by heating at °C to obtain an intermediate whose solid content had an acid value of 171. After this intermediate was cooled, 214.11 mol of trimethylolpropane diallyl ether), 46 g of glycerin (α5 mol) and 0.04 g of hydroquinone were added, and in an inert gas stream, 18
An unsaturated polyester was obtained by heating and dehydrating condensation at 0° C. for 10 hours. After that, this polyester was converted into styrene 162.
An unsaturated polyester resin having a viscosity of UV was obtained. Hereinafter, this will be abbreviated as resin B).

Reference Example 3 [Preparation of unsaturated polyester for comparison] Maleic anhydride 98.11 mol), phthalic anhydride 148i1
mol), propylene glycol 160g (2.1 mol)
Then, 0.0611 of hydroquinone was charged and the mixture was subjected to dehydration condensation under heating at 200° C. for 12 hours in an inert gas stream to obtain an unsaturated polyester having an acid value of 27.2 in solid content. 182 g of styrene was added and dissolved in the total amount of 370 I of this polyester to obtain an unsaturated polyester resin having an acid value of 18 and a viscosity of 8-T.

Hereinafter, this will be abbreviated as tree MC).

Unsaturated polyester *mi obtained in Reference Examples 1 to 5, (
B) Oyori C) Various characteristics of the resin were measured. These results are summarized in Table 1.

Examples 1 to 5 and Comparative Examples 1 to 6 Tree HA obtained in Reference Example 1 as Example 1), Reference Example 2
MB) and cellulose acetate butyrate were blended in the proportions shown in Table 2. Next, the resulting mixture was diluted with styrene and adjusted to a viscosity of 60 seconds using rNK-2 Cup (Iwata Painting Co., Ltd. product), and 4 PHR of a 25% benzoin ethyl ether solution in styrene was added and stirred for woodworking. This was then spray-coated onto a 150 x 300 m1 artificial veneer laminated plywood board of 8111I that had been treated with a urethane sealer in an amount of 20 g/square, followed by a mercury lamp H1000 for light polymerization.
It was cured and dried using TQ (Matsushita Electric Industrial ■ product) at an irradiation distance of 15 cm for 5 minutes.

-1 Various performance tests were conducted on the paints and coating films obtained. The results are summarized in the same table. Also, in the case of Example 2.3 and Comparative Examples 1 to 3, the above This was carried out in the same manner as in Example 1 as described in 1. However, the blending ratios were as shown in the table.

The various performances were measured and judged by the methods described below.

0 Crack resistance・・・・・・・・・Center of painted board and 4
Drill a hole of 8wll0 in the corner and heat it at +70℃ for 1 hour.
A heating/cooling cycle test was conducted in which one cycle was 1 hour at °C, and the number of cycles until cracks appeared in the coating film was measured and determined.

0Surface abrasiveness...50 minutes after mercury lamp irradiation #
The coating film was sanded with 620 sandpaper, and a sensory test was conducted based on both the clogging state of the paper and the force required for sanding, and an overall evaluation was made.

〔Judgment criteria] 0 - Can be easily sanded with little force.

〇 - Can be sanded relatively easily.

8- Although some paper clogging is observed, sanding itself is possible.

×-The paper often gets clogged and sanding is difficult.

0 Lead bride hardness: Measured according to JIS-5400.

As is clear from Table 2, the composition of the present invention was found to be excellent in both crack resistance and surface abrasiveness.

Claims (1)

[Claims] (4) an unsaturated polyester obtained by addition-reacting an unsaturated monoglycidyl compound to an unsaturated polyester containing a carboxyl group at the molecular end; (B) an unsaturated polyester containing an allyl ether group; and (C) a polymerizable monomer.