JPH03185014A - Photo-setting resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition consisting of an unsaturated resin, lactone-modified hydroxyalkyl (meth)acrylate-containing composition having a specific composition and light initiator, capable of reducing viscosity and irradiation of skin without impairing photo-curable property and having high boiling point. CONSTITUTION:The aimed composition obtained by adding (C) 0.1-10 pts.wt. photo-initiator to 100 pts.wt. blend of (A) 20-95wt.% ethylenic unsaturated group- containing resin having >=300 molecular weight and (B) 5-80wt.% lactone- modified 2hydroxyalkyl (meth)acrylate containing composition containing (i) 0-15wt. % >=2 kinds of lactones, (ii) 0-20wt.% hydroxyalkyl (meth)acrylate, (iii) <=5wt.% di(meth)acrylate, (iv) >=10wt.% Michael addition reaction product, (v) residual part of reactive monomer expressed by formula l (R and R1 to R3 are H or CH3; R4 is terminal OH-containing copolymer consisting of monomers expressed by formula II and formula III and addition number of the components A and B is 1-12) and (vi) <=200ppm catalyst.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has a high boiling point and low viscosity, which makes it easy to handle without impairing photocurability, and there is no risk of skin irritation or rash. The present invention relates to a photocurable resin composition with reduced

[Prior art] Generally, lactone-modified hydroxyalkyl acrylate or methacrylate is copolymerized with other radically polymerizable monomers to produce acrylic that has excellent reactivity with crosslinking agents and is highly flexible. A polyol resin can be provided.

It is also useful as an intermediate for reacting with polyisocyanates to synthesize flexible polyfunctional (meth)acrylates containing urethane bonds.

In addition to paints, we also offer photocurable resins, reactive diluents for photocurable resins, flexibility agents for AS resins and ABS resins, acrylic resins, adhesives, adhesives, and flexible eyeglass lenses. It is also used as a material for acrylic emulsions, flexible reactive diluents to replace styrene in unsaturated polyester resins, and polymerizable polyurethane elastomers.

Conventionally, photocurable resins used in printing inks and paints include unsaturated polyester resins, polyurethane resins, epoxy acrylate resins, and unsaturated acrylate resins that have one or more ethylenically unsaturated groups in their molecules. Generally known and widely applied.

[Problems to be Solved by the Invention] However, there is a major problem in that these resins containing ethylenically unsaturated groups lack suitable reactive diluents.

Reactive diluents that are currently widely used include butyl acrylate, 2-ethylhexyl acrylate, and 2-ethylhexyl acrylate.
These include high-boiling monoacrylates such as hydroxyethyl acrylate and isononyl acrylate, and polyacrylates of polyhydric alcohols such as neopentyl glycol diacrylate, which have undesirable properties such as a peculiar odor and skin irritation. .

In general, the properties required of reactive diluents used for resins containing ethylenically unsaturated groups include no skin irritation, good compatibility with the resin, high boiling point, resistance to volatilization, and curing. Reactive diluents that do not impair properties, improve coating film properties, have low viscosity, and are low in cost are still unknown. .

Furthermore, it was revealed in JP-A-58-15 that ε-caprolactone-modified 2-hydroxyethyl acrylate or methacrylate is extremely effective in solving these problems.
4765, but in order to make it easier to use, it is desired to have low crystallinity and improved hydrolysis resistance.

[Means for Solving the Problems] Therefore, the present inventors have conducted extensive studies to obtain a photocurable resin composition that has improved the above-mentioned drawbacks, and have found that ε-caprolactone and β-methyl-δ valerolactone 2 is 2 modified with ε-caprolactone and trimethyl ε-caprolactone.
-Hydroxyethyl acrylate or methacrylate has a high boiling point and no risk of volatilization during work, has good compatibility with resins having ethylenically unsaturated groups, does not cause severe skin irritation, and is lactone-modified. 2-Hydroxyethyl acrylate or methacrylate has low crystallinity and is easy to handle, and its hydrolysis resistance is improved by increasing the hydrophobicity near the ester.

Furthermore, it has characteristics such as being able to impart flexibility to the photocurable resin composition.

Examples of the resin used in the present invention having a molecular weight of at least 300 and having at least one ethylenically unsaturated group in one molecule include the following types.

That is, (a) unsaturated polyester resins obtained by directly esterifying a system consisting of unsaturated acids and dicarboxylic acids or their acid anhydrides and glycols (b) polyester-acrylate resins polyhydric alcohols, polybasic acids or their Those obtained by directly esterifying a system consisting of acid anhydride and acrylic acid in the presence of a catalyst (e) Urethane-acrylate resin Those obtained by reacting unsaturated alcohols such as 2-hydroxyethyl acrylate, polyester polyols, and diisocyanates (d) Epoxy-acrylate resin A reaction product of bisphenol-diglycidyl ether type, glycidyl ester type, alicyclic epoxy resin, etc. having at least two epoxy groups in one molecule with acrylic acid (e) Unsaturated acrylate type These include those obtained by reacting a resin-unsaturated spiroacetal and an unsaturated alcohol such as 2-hydroxyethyl acrylate with a saturated polyhydric alcohol or polyester polyol, or without modification.

These unsaturated resins are mainly composed of oligomers or polymers having at least one, preferably two or more ethylenically unsaturated groups in one molecule.

The molecular weight of the resin having ethylenically unsaturated groups is at least 300, preferably from 300 to 5000. If the molecular weight is less than 300, film forming properties are insufficient.

On the other hand, if the molecular weight is extremely large, the viscosity becomes too high, which not only deteriorates the coating properties but also reduces the adhesion to the substrate, which is not preferable.

Two or more types of the above unsaturated resins may be used in combination.

Further, if necessary, a polyacrylate of a polyhydric alcohol that is less irritating to the skin (for example, trimethylolpropane triacrylate, pentaerythritol triacrylate, etc.) can be used in combination.

The composition contains, on average, 0.3 to 12 moles of the various lactones represented by the general formula (I) used in the present invention.

(a) 0 to 15% by weight of at least two lactones (b) 0 to 20% by weight of hydroxyalkyl acrylate or methacrylate (C) not more than 5ffi weight % of diacrylate or dimethacrylate (d) ICI weight % quantum Below is frog addition, acrylic polymerization,
Products obtained from transesterification or other side reactions (e) RROR2R3 1 CH-C-C-OCH-CH-0-R4 (1) RSRSR2, R3-H, CH3 48 11
...-C-(CH2) 50- 〇 CH3 111... -CCHCHCHCH20- 2 0CH3CH3 1 -CCHCH-CH2CCH20- (A) (B) (C) CH3 CH3 CH3 1 CCH2 C-C)l,.

CHCH20- CD) CH3 CH3 body or random or alternating copolymer of A, B and C and has an OH group at the end; A+B, or A
+C+D is an addition number on average from 1 to 12; and (f) a residual amount relative to 100% by weight of reactive monomer, and (f) not more than about 200 ppm of catalyst.

and optionally (g) a reactive monomer composition (raw material) containing an inert solvent; hydroxyalkyl acrylate or Methacrylate is industrially produced by reacting acrylic acid or methacrylic acid with ethylene oxide in the presence of a catalyst, followed by distillation.

In addition, the other starting material components, lactones, include -caprolactone, 3,3,5-trimethylε-
Examples include caprolactone, 3,5.5-trimethyl ε-caprolactone, β-methyl-δ valerolactone, and at least two of these can be used by mixing them in any ratio.

Industrially, ε-caprolactone is mainly used, and 3.3.5-trimethyl ε-caprolactone, 3,5.5-ε-caprolactone or β-methyl-6-valerolactone is optionally used depending on the purpose. It is advantageous to add in proportions.

ε-caprolactone 3,3.5-trimethyl ε-caprolactone and 3.5.5-ε-caprolactone used in the present invention are obtained by oxidizing cyclohexanone and 3.3°5-trimethylcyclohexanone by Baeyer-Billiger reaction using peracid. can be manufactured.

In particular, 3,5,5-trimethyl ε-caprolactone and 3,3,5-1-trimethyl ε-caprolactone are 3.5.
When 5-trimethylcyclohexanone is reacted with peracid, it can be obtained as a mixture, but the mixture can be separated by various methods and polymerized alone, or it can be used as a mixture.

β-Methyl-δ-valerolactone is 2-hydroxy-4
- It can be produced using methyltetrahitomipyran as a raw material.

Lactones are 1 mole of hydroxyalkyl acrylate or hydroxyalkyl methacrylate.
~20 mol, preferably 1 to 10 mol, is reacted.

When 1 mole of each of the two types of lactones is reacted with 1 mole of hydroxyalkyl methacrylic acid ester, the ring-opening reaction rate of the lactone to the hydroxyl group of the hydroxyalkyl methacrylic acid and the opening of the lactone to the hydroxyl group at the lactone end of the product are Since the ring reaction rate does not change significantly, the reactants have the formula (n
) (blank below) Rio R 3 1 CH2-C-C-0-CH-CHO- R4, R is either HSCH3, and R4, R5 can be changed to each group at the same time. x-4,5 n-0 to 12 From the unreacted material of n-0, n-1,2,3,4,5...
adducts are statistically distributed in a mixed state. The average value of n is preferably 0.3 to 12.

Resin with ethylenically unsaturated group and lactone-modified 2-hydroxyethyl acrylate (or methacrylate)
Although the mixing ratio with the composition is not necessarily limited, it is usually 95 to 40% by weight of the unsaturated resin and 5 to 5% by weight of the lactone-modified 2-hydroxyethyl acrylate (or methacrylate).
From the viewpoint of coating film performance and curing speed, preferably 90 to 50% by weight of the acrylate resin and 10-50% by weight of the lactone-modified 2-hydroxyethyl acrylate or methacrylate composition.

Examples of photosensitizers used in the present invention include benzoin, benzoin methyl ether, benzoin isopropyl ether, acetophenone, benzophenone, anthraquinone, benzophenone or a combination system of benzophenone derivatives and amines, and benzyl. I can give what I have.

Two or more of these photoinitiators may be used in combination.

The amount of the photosensitizer added is 0.1 to 10 parts by weight per 100 parts by weight of the mixture of the unsaturated resin and the ε-caprolactone-modified 2-hydroxyethyl acrylate or methacrylate.

If the amount of photosensitizer added is less than 0.1 parts by weight, it is not preferable because curing takes a long time;
If it is more than 0 part by weight, not only no particularly remarkable effect is observed, but also phenomena such as coloring of the coating film and deterioration of coating performance are observed, which is not preferable.

The photocurable resin composition of the present invention may contain dyes, pigments, glass fibers, fillers, etc. within the range that does not impair photocurability.

Since the photocurable resin composition of the present invention has various characteristics as described above, it is useful for printing inks, paints, adhesives, transparent molded products, etc. that are cured by irradiation with ultraviolet rays, electron beams, etc. .

The present invention will be explained in detail below using Examples, but the present invention is not limited thereto.

In the examples, parts mean parts by weight.

Synthesis Example-1 In a 3-g four-piece flask, 1,900 g of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane hydroxylate (Celoxide 2021 manufactured by Daicel Chemical Industries, Ltd.), which is a cycloaliphatic epoxy resin, 720 g of acrylic acid, and amine were added. System contact W7.2g, hydroquinone 10
When the mixture was heated and stirred at 110 to 130°C for about 2 hours, an epoxy-acrylate resin with an acid value of 3.0° was obtained.

The epoxy-acrylate resin has a molecular weight of 417, a viscosity of about 500 voids at 50°C, and is yellowish brown syrup-like.
It was impossible to paint it as it was.

Example-1 80 parts of epoxy acrylate of Synthesis Example-1 and Synthesis Example-1
After uniformly dissolving 20 parts of lactone-modified hydroxyethyl acrylate, 2 parts of benzoin methyl ether
A photocurable resin composition was prepared.

As is clear from Table 1, the photocurable resin composition of the present invention is capable of reducing viscosity and skin irritation, as well as imparting flexibility, with almost no reduction in physical properties.

Example-2 80 parts of epoxy acrylate of Synthesis Example-1 and Metal Synthesis Example-2
After uniformly dissolving 20 parts of lactone-modified hydroxyethyl methacrylate, 20 parts of benzoin methyl ether
A photocurable resin composition was prepared.

As is clear from Table 1, the photocurable resin composition of the present invention is capable of reducing viscosity and skin irritation, as well as imparting flexibility, with almost no reduction in physical properties.

Claims (1)

[Claims] A resin 20 to 95 having a molecular weight of at least 300 and having at least one ethylenically unsaturated group in one molecule.
% by weight, and a composition containing a compound represented by the general formula ▲ Numerical formula, chemical formula, table, etc. ▼, namely: (a) 0 to 15% by weight of at least two lactones (b) 0 to 20% by weight hydroxyalkyl acrylate or methacrylate (c) up to 5% by weight of diacrylate or dimethacrylate (d) up to 10% by weight Michael addition, acrylic polymerization;
Products obtained from transesterification reactions or other side reactions (e) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (I) R, R_1, R_2, R_3=H, CH_3R_4; ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼・・・(A) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・(B) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・(C) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・...(D) R_4 is a random or alternating copolymer of A and B or a random or alternating copolymer of A, B, and C and has an OH group at the end; A+B) or A+C+
D is an average addition number of 1 to 12; and (f) a composition comprising about 200 ppm or less of a catalyst and optionally (g) an inert Reactive monomer composition containing a solvent: If necessary, 0.0% of a photoinitiator is added to 100 parts by weight of a mixture with 5 to 80% by weight of a lactone-modified 2-hydroxyalkyl acrylate or methacrylate-containing composition represented by: A photocurable resin composition containing 1 to 10 parts by weight.