JPS6254710A - Urethane-modified acrylate composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a composition that is cured to produce a highly durable urethane-modified acrylate using a urethane-modified acrylate and a polymerizable monomer as raw materials.

Conventional technology In recent years, many radiation-curable resin compositions have been developed and are being used in paints, adhesives, pressure-sensitive adhesives, binders for magnetic tapes, etc., and the scope of their use is expected to further expand in the future. . Among these, urethane-modified acrylates are weakly anaerobic and can polymerize even at high oxygen concentrations, and the physical properties of the cured product vary greatly depending on its structure (type of diisocyanate, type of polyol, molecular weight, degree of condensation, etc.) It is attracting attention because of its great variety. As urethane-modified acrylate resins consisting of urethane-modified acrylate and polymerizable monomers, those having various compositions are known (
For example, Japanese Patent Publication No. 39-14805, Japanese Patent Publication No. 45-1
5629, JP 47-13693, JP 48-25095, JP 55-54316, JP 59-191772, U.S. Patent No. 5
No. 297745, etc.).

Problems to be Solved by the Invention However, urethane has good adhesion, adhesion, flexibility, and toughness to various adherends including metals, and at the same time has hydrolysis resistance and weather resistance. Currently, modified acrylate resins have not yet been obtained.

An object of the present invention is to provide a urethane-modified acrylate resin that has excellent hydrolysis resistance, weather resistance, strength and elongation, flexibility, elasticity, adhesion, and adhesion.

Means for Solving the Problems According to the present invention, the above object is to provide a urethane-modified acrylate composition comprising a urethane-modified acrylate and a polymerizable monomer, in which the urethane-modified acrylate has the following general formula (1) % formula: % (wherein R+ and R′+ are hydrogen or methyl group, R2
1 m of polyester polyol residues is a number of 1 to 5.

l and n represent integers of 1 to 3. ) is achieved by using a compound represented by:

The urethane-modified acrylate represented by the general formula (1) used in the present invention is manufactured from a polyester polyol, an organic diincyanate, and a hydroxyl group-containing acrylate or methacrylate, has a urethane bond in the polymer main chain, and has a urethane bond at the polymer end. is a polymer having an acryloyl group or a methacryloyl group.

~10,000. By using the polyester polyol containing the above-mentioned methyl branched C6 group in the molecule, the resulting composition has excellent overall hydrolysis resistance, solvent resistance, and flexibility, and at the same time,
Pigment dispersibility becomes particularly good. The above structure of polyester has odd-numbered carbons arranged in a straight line, so it has excellent pigment dispersibility, and since it has methyl branches, it is not a product, and it has particularly good low-temperature flexibility, and it also has better adhesion to substrates than polyester. Specifically, polyol is 3-methyl-1,
5-bentanediol or a low molecular weight polyol containing it, adipic acid, succinic acid, glutaric acid, pimelic acid, cepatic acid, azelaic acid, terephthalic acid, isophthalic acid, maleic acid.

Polyester polyols synthesized from dicarboxylic acids such as phthalic acid are specifically poly(β-methyl-
[delta]-valerolactone] polyol or a polyol mixture containing the same, or a block or random copolymerized polyol obtained by ring-opening copolymerization with β-methyl-delta-valerolactone as one component.

Poly(β-methyl-δ-valerolactone) polyol is obtained by ring-opening polymerization of β-methyl-δ-valerolactone with a low-molecular polyhydric alcohol such as ethylene glycol or butanediol.

Furthermore, copolymers 1 with other lacto/copolymers may be obtained by fully ring-opening copolymerization with ε-cabrolactone and β-methyl-δ-valerolactone, or with adipate polyester polyols and β-methyl A block polymer polyol made from -δ-valerolactone may also be used.

The organic diincyanate used in the present invention may be any of the known aromatic, aliphatic, alicyclic, and incyanate compounds having two incyanate groups.
4'-diphenylmethane diisocyanate, p-7 22 diisocyanate, toluylene diinocyanate,
1,5-naphthylene diisocyanate, xylylene diisocyanate.

Examples include hexamethylene diisocyanate, inphorone diisocyanate, 4,4'-dicyclohexylmethane diincyanate, bis(incyanatomethyl)cyclohexane, and the like.

Examples of acrylates or methacrylates containing hydroxyl groups include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 1
, 9-nonanediol mono(meth)acrylate, propylene oxide-modified mono(meth)acrylate, caprolactone-modified mono(meth)acrylate, trimethylolethane di(meth)acrylate, trimethylolpropane di(meth)acrylate, pentaerythritol tri(methane) Acrylate etc. can be raised.UV
When curing with acryloyl and methacryloyl groups, the reaction rate is:

Since acryloyl groups are overwhelmingly fast, it is preferable to use acrylates.

The reaction ratio between the polyester polyol and the organic diisocyanate is based on the hydroxyl group (
OH) is less than 1 (
OH/NCO<1). By reacting at the above reaction rate, a prepolymer containing terminal incyanate groups can be obtained. The reaction temperature is 20-150°C, especially 50-10°C.
Preferably, it is carried out at 0°C. Catalysts include triethylenediamine, triethylamine, and dibutyltin dilaurate.

Dimethyloctyltin and the like are preferred.

The terminal inocyanate group-containing prepolymer obtained by the above reaction is then reacted with a hydroxyl group-containing (meth)acrylate to produce a urethane-modified acrylate. The amount of hydroxyl group-containing (methane acrylate) is preferably such that the compound (reaction molar ratio OH/NCO) is equal to or more than the equivalent molar amount to the incyanato groups in the prepolymer containing terminal incyanato groups.The molecular weight of this urethane-modified acrylate is 1000-20000, preferably 20
00-15000.

Polymerizable monomers to be blended with the urethane-modified acrylate include nostyrene monomers such as styrene, vinyltol, ene, chlorostyrene, and divinylbenzene, methyl methacrylate, methyl acrylate, and 1,6-hexamethylene. Glycol diacrylate, neopentyl glycol diacrylate, polyethylene glycol diacrylate.

Monoacrylates and polyacrylates such as 2-ethylhexyl acrylate, dicyclohexylpentagenyl acrylate, hentaerythritol triacrylate, trimethylolpropane triacrylate, allylic monomers such as diallyl phthalate, triallyl cyanurate, vinyl acetate, dibutyl 7 malate, etc., and one or more of these may be blended.

The above urethane-modified acrylate can be mixed with these polymerizable monomers to form a urethane-modified acrylate resin. The mixing ratio of urethane-modified acrylate and various polymerizable monomers is 95:5 to 5:95, preferably 90:
The weight ratio is 10 to 30.

In order to further improve the adhesion and adhesion performance of the composition obtained in this way, the general formula (Rin) (wherein R5 is hydrogen or a methyl group, R6 is a divalent organic group, and q is 1 or 2
, r can be 1 or 2, and q + r = 3.

) A phosphorus-containing (meth)acrylate represented by the following may be added. Examples of phosphorus-containing (meth)acrylates include mono[ethyl 2-(meth)acrylate] phosphate, mono[2-(meth)propyl acrylate], and di[ethyl phosphate].
2-ethyl (meth)acrylate], di[2-(
propyl meth)acrylate], etc. The amount of phosphorus-containing (meth)acrylate added is 5% of the total resin.
It is preferably 0% by weight or less.

In addition, in order to prevent radical polymerization of the produced urethane-acrylate, a radical polymerization inhibitor of about 0.001 to 0.05% by weight can be added to the system.
Examples of the inhibitor include hydroquinone, hydroquinone monomethyl ether, and the like.

As a means for curing the composition of the present invention, for example, electron beam curing, ultraviolet curing, thermosetting, or any other known means can be employed. .

When curing the composition of the present invention with ultraviolet light, a photoinitiator as shown below is added. Specific examples thereof include benzophenone, p-methoxybenzophenone, acetophenone, propiophenone, xa7ton, benzoin, benzoin ethyl ether, anthraquinone, naphthoquinone, etc., and the amount thereof is determined based on the urethane-modified acrylate contained in the composition. Add approximately 0.1 to 15% by weight. At this time, a photoactive agent such as methylamine, jetanolamine, N-methyljetanolamine, or tributylamine may be added.

When the composition of the present invention is cured by heat, known radical polymerization initiators such as hydrogen peroxide, benzoyl peroxide, cumene peroxide, t-butyl hydroperoxide, azobisbutyronitrile, etc. are used. be able to.

When curing by electron beam irradiation, it is not particularly necessary to add a photoinitiator or a radical polymerization initiator.

No matter which of these curing methods is adopted, the urethane-modified acrylate resin obtained by the present invention is tough and has excellent hydrolysis resistance, weather resistance,
Provides a cured product with flexibility, adhesion, and adhesive properties. Furthermore, the internal strain caused by volume shrinkage during curing is small, making it particularly useful as an adhesive.

In addition, various conventional additives can be added to the composition of the present invention depending on the purpose of use within a range that does not impair the purpose of the present invention.

More specifically, the urethane-modified acrylate resin obtained by the present invention is useful in paints, coatings, adhesives, ink sealants, and the like.

Examples In order to explain the present invention more specifically, the following examples are given below.
A comparative example will be given. In the example, "middle part" indicates the mold needle part.

The performance of the cured coating film was determined by the following method.

(1) Adhesion: how many out of 100 test pieces were adhered by the method of peeling cellophane tape (x/100)
Indicated by

(4) Flexibility: A tanzak-shaped test piece with a width of 5Qm and a length of 10z was bent along the outer periphery of a cylinder with a diameter of 21 and the coating was judged to be cracked.

(110 water resistance; test piece 'i 24 in pure water at 40°C
After immersion for 0 hours, the appearance and adhesion of the outer coating layer (method according to (1) above) were evaluated.

(1v) Weather resistance: The test piece was held in a sunshine weather oven for 600 hours, and the appearance and adhesion of the outer coating layer (method according to (1) K above) were evaluated.

Example 1 3-methyl-1,5-bentanediol 920.0Q,
876 g of adipic acid (diol/acid molar ratio 1.5/
1) Esterification was carried out under normal pressure while passing two gases through and distilling condensed water at a temperature of about 210°C. When the acid value of the polyester became 0.3 or less, the degree of vacuum was gradually increased using a vacuum pump to complete the reaction. In this way, a polyester polyol (hereinafter referred to as polyester (a)) having a hydroxyl value of 56% and an acid value of 0.1 was obtained. This polyester (a) was liquid at room temperature and had a molecular weight of about 2,000.

To 500 parts of this polyester (a) were added 111 parts of inphorone diisocyanate and 0.2 parts of di-n-butyltin dilaurate as a catalyst, and the mixture was heated and stirred at 80°C for 6 hours to obtain a urethane prepolymer containing terminal incyanato groups. Ta.

Next, 58 parts of 2-hydroxyethyl acrylate and 0.4 parts of hydroquinone monomethyl ether were added, and the mixture was heated at 60°C.
After reacting for 6 hours, 200 parts of 1,6-hexanediol diacrylate was added to obtain a urethane-modified acrylate blend.

A coating composition was prepared by adding 3 parts of benzoin ethyl ether to 100 parts of the obtained urethane-modified acrylate formulation. This was applied onto an aluminum plate with a 75 micron applicator and irradiated with an output of 80 W/2 using a high-pressure mercury lamp. The coating film became stain-free by irradiating it twice at a speed of 6 m/min, and was completely cured by irradiating it four times. A coating film that had been irradiated six times was used to measure the three physical properties. .

Examples 2 to 6 Urethane-modified acrylate resins with the compositions shown in Table 1 were obtained using the same molar ratio and the same method as in Example 1.

In Examples 1 to 4, adipic acid/azelaic acid =
'/1 (molar ratio), adipic acid/isophthalic acid -1/1
(molar ratio), azelaic acid/in7talic acid = 1/1 (molar ratio), 5-methyl-1,5-bentanediol/1.
6-hexanediol=171 (molar ratio).

Comparative Examples 1 to 5 Each urethane-modified acrylate resin was obtained using the same molar ratio and the same method as in Example 1 with the composition shown in Table 1. Coating film properties and film tensile strength of the cured product of each resin Strength and elongation at break were measured, and as described above, the present invention discloses a urethane-modified acrylate resin that has excellent flexibility, film properties, adhesion, water resistance, weather resistance, etc. It is extremely useful industrially.

Claims (2)

[Claims] (1) In a urethane-modified acrylate composition consisting of a urethane-modified acrylate and a polymerizable monomer, the urethane-modified acrylate has the following general formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R_1 and R_1 ' is hydrogen or methyl group, R
_2 and R_2' are polyhydric alcohol residues, R_3 is an organic diisocyanate residue, and R_4 is ▲There are mathematical formulas, chemical formulas, tables, etc.▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼ as a constituent component. Polyester polyol residue, m is 1
The number ˜5, l and m represent integers of 1-3. ) A urethane-modified acrylate composition characterized by being a compound represented by: (2) General formula (II) ▲Mathematical formulas, chemical formulas, tables, etc.▼(II) (In the formula, R_5 is hydrogen or a methyl group, R_6 is a divalent organic group, q is 1 or 2, r is 1 or 2 and q+r
=3. 2. The urethane-modified acrylate composition according to claim 1, characterized in that the third component is an acrylate represented by: