JPH0418412A - Thermosetting composition - Google Patents

Abstract

PURPOSE:To obtain a thermosetting composition having excellent hardness, decoration, solvent resistance, etc., by blending a mixture of a specific aliphatic and/or alicyclic urethane (meth)acrylate and a specific aliphatic and/or alicyclic urethane (meth)acrylate with a radical-polymerizable compound and a radical polymerization initiator in a specific ratio. CONSTITUTION:(A) 50-100 pts.wt. mixture having 40-100 deg.C glass transition temperature of coating film measured by dynamic viscoelasticity of an aliphatic and/or alicyclic urethane (meth)acrylate containing three or more (meth)acryloyl groups having <40 deg.C glass transition temperature of coating film and an aliphatic and/or alicyclic urethane (meth)acrylate containing three or more (meth)acryloyl groups having >=60 deg.C glass transition temperature of coating film is blended with (B) 0-50 pts.wt. radical-polymerizable compound containing three or more (meth)acryloyl groups free from urethane bond, having >=300 molecular weight and (C) 0.1-3.0 pts.wt. based on 100 pts.wt. components A+B of a radical- polymerizable compound having >=300 molecular weight and (C) 0.1-3.0 pts.wt. based on 100 pts.wt. components A+B of a radical polymerization initiator to give a thermosetting composition.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a thermosetting material having excellent hardness, cosmetic properties, solvent resistance, weather resistance, and flexibility, as well as good acid resistance and scratch resistance. Regarding the composition.

[Prior art and its problems] Conventionally, the formation of coating films using radically polymerizable unsaturated group-containing oligomers requires the combined use of photosensitizers and ultraviolet irradiation, and in the curing reaction by heating, hardness, solvent resistance, It was thought that a cured coating film with good properties such as weather resistance could not be obtained.

However, the present inventors believe that even if heat curing is used,
If the radically polymerizable oligomer has a specific bond and has a molecular weight above a certain level, it can exhibit hardness and weather resistance similar to those found in acrylic resins, and also has acid resistance, which was low in melamine crosslinked systems. It was also found that good results were obtained in terms of durability and scratch resistance.

That is, an object of the present invention is to provide a thermosetting composition that has excellent hardness, cosmetic properties, solvent resistance, weather resistance, and flexibility, and also has good acid resistance and scratch resistance. It is in.

[Means for Solving the Problems] The gist of the present invention is that (a) an aliphatic and/or alicyclic urethane (meth)acrylate containing three or more (meth)acryloyl groups in one molecule; , the glass transition temperature of the coating film measured by dynamic viscoelasticity was 4.
A mixture consisting of component A having a temperature of less than 0°C and component B having a temperature of 60°C or higher, 50 to 100 parts by weight of a composition having a glass transition temperature of 40 to 100°C, (b) (meth)acryloyl in one molecule; A radically polymerizable compound containing 3 or more groups, no urethane bonds, and a molecular weight of 300 or more, with a weight of 0 to 50! Component (a) and (1)), and (c) a radical polymerization initiator.
0.0% for 1 part by weight of the total components. 1-3.
0 parts by weight of the thermosetting composition.

3 (meth)acryloyl groups in one molecule, which is the first component.
Aliphatic and/or alicyclic urethane (meth)acrylate containing @ or more (a) is triiso/anate alone,
It can be synthesized by reacting a polyisonoanate such as a vinylet, a polymer, or an adduct of diisocyanate or triisoananate with a polyol, and a hydroxyl group-containing monomer. The glass transition temperature (hereinafter referred to as Tg) of the urethane (meth)acrylate polymer can be determined from the maximum value of the temperature dispersion curve by measuring the dynamic viscoelasticity of the crosslinked coating film. In the present invention, Tg is 40°C
Component A, which is the following urethane (meth)acrylate,
Composition (a) is obtained by mixing component B, which is a urethane (meth)acrylate with a Tg of 60°C or higher, and has a Tg of 40 to 100°C. If the glass transition temperature of component A or component B is higher than 50°C or lower than 60°C, the appearance will not be satisfactory. Flexibility is insufficient when component A or component B is used alone. In addition to this, it is necessary to adjust the glass transition temperature of composition (a) in the range of 40-100'C. If it is less than 40'C, solvent resistance, scratch resistance, etc. will decrease, and if it exceeds 100C, weatherability will decrease. Further, the usage amount is 50 to 100 parts by weight, and less than 50 parts by weight is not preferable because weather resistance deteriorates.

Specific examples of polyisonoanates include ethylene diison abut, 1,2-diisocyanatofuropane, 1,3
-diincyanatopropane, 44-dipheny, lumetane diisocyanate, hexamethylene diisocyanate,
Lysine isocyanate, 4.4-methylenebis(cyclohexyl) incyanate, methylcyclohexane 2
, 4-diisocyanate, methylcyclohegyusan 26-
Diisocyanate, diisocyanate such as 1,3-bis(isocyanatomethyl)cyclohexane, inphorone diisocyanate, trimethyl ester diisocyanate, tetramethylene diisocyanate, dimer acid diisonanate, simple substance of triiso/anate, biuret and its polymer, Examples thereof include adducts with polyols. Specific examples of polyols used in the adduct include ethylene glycol, propylene glycol, futhyrenoglyfur, polyethylene glycol,
Polyfuropyrenoglycol, polynophthylene glycol, polytetramethylene glycol, trimethylolflobano, polytrimethylolfuropane, bentaeryswatol, :f:') he7taeryswatol, sorbitol, mannitol, glycerin , polyester polyols such as alcohols and polyether polyols such as polyglycerin, polyester polyols synthesized from polyhydric alfur and polybasic acids, and polyester polyols such as polycaprolactone polyols.

Examples of hydroxyl group-containing vinyl monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxalpyl (
meth)acrylate, 3-hydrobovine dipropyl(meth)
acrylate, hydroquine alkyl (meth)acrylates such as 4-hydroquine butyl (meth)acrylate,
Adducts of 2-hydroxyethyl (meth)acrylate and ethylene ookinde, adducts of 2-hydroxyethyl (meth)acrylate and brobylenookinde, adducts of 2-hydroquinoethyl (meth)acrylate and ε-caprolactone, etc. Examples include adducts of 2-hydroquinoethyl (meth)acrylate and organic lactones.

The reaction between polyisonore and a hydroxyl group-containing monomer is as follows:
A tin-based catalyst such as dibutyltin dilaurate is used so that the isocyanate and hydroxyl groups are approximately equal in amount to 60 to 7
Finish by heating for several hours at 0°C.

The radically polymerizable compound (b), which is the second component, has a molecular weight of 300 or more and does not have a urethane bond, and the total amount of components (a) and (b) in the composition of the present invention is 100.
0 to 50 parts by weight, preferably 10 to 40 parts by weight
It is added in parts by weight, and if it exceeds 50 parts by weight, weather resistance decreases, which is not preferable.

Specifically, polyester poly(meth)acrylate and epoxy resin obtained by reacting polybasic acids such as phthalic acid and adipic acid with polyhydric alcohols such as ethylene glycol and butanediol and (meth)acrylic acid compounds. Ebogyu/poly(meth)acrylate obtained by the reaction with (meth)acrylic acid compound, polysiloxane poly(meth)acrylate obtained by the reaction of boria xane and (meth)acrylic acid compound, polyamide and (meth) ) Polyamide poly(meth)acrylate obtained by reaction with an acrylic acid compound.

The radical polymerization initiator (c) is present in the composition of the present invention.
) component and (1)) total amount of component 1001! 0.1 to 3.0 parts by weight are added to 1 part of ij, and if it is less than 0.1 part by weight, sufficient coating hardness cannot be obtained; If it exceeds 0 parts by weight, the stability of the coating material decreases, which is not preferable. Examples of the polymerization initiator used here include benzoyl peroxide, cumene hydroperoxide, di-t-butyl hydroperoxide, dicumyl peroxide,
peroxides such as t-butyl peracetate, t-butyl perbenzoate, and t-butyl hydrocarbon halfside;
Azobisisobutyronitrile, 2,2-azobis(2-
methylbutyronitrile), 1. 1-Abbis (Nokurohegyusuno 1-carbonide lnor), 22-Azobis(
Examples thereof include azo compounds such as 2,4-dimethylvaleronitrile) and 22-azobis(2-methylfuropane), but are not particularly limited.

The thermosetting composition of the present invention has a temperature of 15 to 45% at 100°C or higher.
This can be achieved by changing the curing conditions for a few minutes. In addition, the cured product of the composition of the present invention has excellent hardness, cosmetic properties, weather resistance, and solvent resistance, as well as good acid resistance and scratch resistance.
It is useful as a paint or coating agent for the surfaces of inorganic materials (iron plates, tin plates, galvanized iron plates, aluminum plates, galvanized steel sheets, roof tiles, etc.) and organic materials (wood, paper, plastic, organic paint films, etc.).

Furthermore, surface conditioners, anti-cissing agents, ultraviolet absorbers, antioxidants, organic solvents, and other additives may be added as necessary.

The present invention will be explained in detail below using examples.

Measuring method of glass transition temperature> A coating film with a dry thickness of 100 μm baked at 140″C for 40 minutes was measured using a dynamic viscoelasticity measuring device (RHEOVIBRON DDI/-11-EP manufactured by 11-Yo Gildwin Co., Ltd.). The glass transition temperature was determined by reading the temperature at the maximum value of the dynamic viscoelastic temperature dispersion curve.

Production example of urethane (meth)acrylate (a)-1〉 1 mol of urethane (meth)acrylate (a)-1 and 1 mol of dibutyl tin dilaurate and 1-0.002 mol of dibutyl tin dilaure were added to a reaction vessel, and heated at 70″C. After raising the temperature to , 1 mol of polybutylene glycol was added dropwise over 1 hour, and the mixture was allowed to react at the same temperature for 3 hours. Furthermore, 3 mol of pentaerythritol triacrylate was added dropwise over 1 hour, and after the addition, the mixture was allowed to react for 5 hours. , urethane (meth)acrylate (a)-1 having a glass transition temperature of 117°C was obtained.

Production example of urethane (meth)acrylate (a)-2> Isophorone diisocyanate puree instead of hexamethylene diisone abuture, 0.00 mole of dibutyltin dilaurate instead of 0.002 mole
Production example except that 1 mol and 2-hydrobor/propyl acrylate is used instead of polybutylene glycol.
Urethane (meth)acrylate (a)-2 having a glass transition temperature of 94°C was obtained in the same manner as in Example 1.

Production example of urethane (meth)acrylate (a)-3〉 1 mol of urethane (meth)acrylate (a)-3 and 0.002 mol of dibutyl tin dilaurate were added to a reaction vessel, and the temperature was raised to 70°C. After that, 3 mol of propylene glycol was added dropwise over 1 hour, and the reaction was then carried out at the same temperature for 3 hours.
mol was added dropwise in 1 hour, and reacted for 5 hours after the addition.
Urethane (meth)acrylate (a)-3 having a glass transition temperature of 62°C was obtained.

Production example of urethane (meth)acrylate (a)-4> 0.001 mol of dibutyltin dilaurate instead of 0.002 mol, 3 mol of butylene glycol instead of 1 mol of polybutylene glycol, and hibentaerythritol Urethane (meth)acrylate (a)-4 having a glass transition temperature of 56° C. was obtained in the same manner as Production Example-1 except that 2-hydrobutyl acrylate was used instead of triacrylate.

Production example of urethane (meth)acrylate (a)-5> Production example except that 3 moles of polyethylene glycol was used instead of 1 mole of polybutylene glycol, and 2-hydroquinpropyl methacrylate was used instead of 2-hydroxypropyl acrylate. In the same manner as in 2, urethane (meth)acrylate (a)-5 with a glass transition temperature of 49°C
I got it.

Production example of urethane (meth)acrylate (a)-6> Instead of vinylet, 311 units of methylenodiisocyanate and 0.002 mol of dibutyltin dilaurate were used. 0.00
Urethane (with a glass transition temperature of 27°C) was prepared in the same manner as in Production Example-1, except that 1 mol of polybutylene glycol was used, 3 mol of polybutylene glycol was used instead of 1 mol, and 2-hydroquine ethyl acrylate was used instead of pentaerythritol triacrylate. Meth)acrylate (a)-6 was obtained.

Production example of urethane (meth)acrylate (a)-7> Hexamethylene diisocyanate instead of the afi form of hexamethylene diisocyanate, 2 moles instead of 3 moles of polyethylene glycol, and 3 moles of 2-hydroxyethyl acrylate Urethane (meth)acrylate (a)-7 having a glass transition temperature of 38° C. was obtained in the same manner as Production Example-6 except that 2 mol was used.

Example of production of acrylic resin varnish> 53.3 times of Tsurupetz #xOO was added to a container equipped with a stirrer, a temperature control device, and a condenser. Next, the temperature was raised to 120° C. with stirring, and then 2 parts by weight of abbisisobutyronitrile and t-butylperoxycarbonate double ttM were added and mixed to 100 parts by weight of the following monomer mixture. was added dropwise over 3 hours. Next, while stirring the mixture, o and i parts by weight of azobisisobutyronitrile were added four times at 30 minute intervals.

Further, the reaction mixture was heated and stirred at 120''C for 2 hours to increase the reaction rate, and then 13.3 parts by weight of n-butyl acetate was added to terminate the reaction and an acrylic resin varnish was obtained.

(Monomer mixture) Styrene 25 parts by weight Methacrylic acid 3 parts by weight n-butyl methacrylate 20 parts by weight t-butyl methacrylate 5 parts by weight 2-ethylhexyl methacrylate 29 parts by weight 2-hydroxyethyl methacrylate 18 parts by weight <Examples 1 to 7, Comparative Examples 1 to 8> After degreasing the steel plate, the various compositions shown in Table 1 were applied onto the steel plate to a dry film thickness of 35μ, and after being left at room temperature for 10 minutes, Baking was performed under the curing conditions shown in -1. The coating film performance evaluation results of the obtained paint films are shown in Table 2, and the examples have better hardness, cosmetic properties, solvent resistance, weather resistance, flexibility, and better appearance than the comparative examples.
Both acid resistance and scratch resistance were excellent.

[Effects of the Invention] As detailed above, the composition of the present invention can be cured by heat, and the obtained cured coating film has good hardness, cosmetic properties,
It has excellent solvent resistance, weather resistance, flexibility, acid resistance, and scratch resistance, and has extremely high industrial significance.

Claims (1)

[Scope of Claims] (a) An aliphatic and/or alicyclic urethane (meth)acrylate containing three or more (meth)acryloyl groups in one molecule, the glass transition temperature of the coating film measured by dynamic viscoelasticity measurement. is 4
A mixture consisting of component A having a temperature of less than 0°C and component B having a temperature of 60°C or higher, 50 to 100 parts by weight of a composition having a glass transition temperature of 40 to 100°C, (b) (meth)acryloyl in one molecule; 0 to 50 parts by weight of a radically polymerizable compound containing 3 or more groups, no urethane bonds, and a molecular weight of 300 or more, and (c) a radically polymerizable initiator, the sum of components (a) and (b). A thermosetting composition comprising 0.1 to 3.0 parts by weight per 100 parts by weight.