JPH0124168B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an active energy ray-curable composition, and more specifically, an active energy ray-curable composition that cures in an extremely short time by irradiation with ultraviolet rays or electron beams, and has excellent adhesion to substrates and bendability. It is about things. In recent years, active energy ray-curable compositions have been put to practical use in a wide range of fields such as printing inks, clear varnishes, coatings, adhesives, and photoresists, and a typical example is radical polymerization of acryloyl groups. The main components are prepolymers, oligomers, and monomers having sexual double bonds, and if necessary, sensitizers, colorants, etc. that generate radicals when exposed to ultraviolet rays are blended therein, or
There are bisphenol type epoxy resins, alicyclic epoxy resins, polyglycidyl esters, etc., which are blended with catalysts that generate Lewis acids when exposed to ultraviolet rays. Conventionally, when these active energy ray-curable compositions are used as coating compositions, the adhesion may be insufficient depending on the target metal material and the type of various organic coating coated plates, or there may be problems with bending. There were problems with processing resistance such as hardness and punching properties, and it was not necessarily practical. For example, those using acrylic acid-modified epoxy resins have a fast curing speed and high surface hardness, but they have insufficient adhesion to non-absorbent substrates such as metal materials and organic coated boards; Those using urethane resin have excellent flexibility but have a slow curing speed, and although they exhibit good adhesion to some non-absorbent substrates, they have problems such as high resin viscosity. The object of the present invention is to cure metal materials such as tin plate, TFS plate, aluminum plate, alkyd resin, vinyl resin, epoxy resin, phenolic resin, polyester resin extremely quickly by irradiation with active energy rays, especially ultraviolet rays or electron beams. ,
It is an object of the present invention to provide a resin composition that exhibits good adhesion to painted plates coated with acrylic resin or the like and has excellent processing resistance such as bendability and punchability. That is, the present invention comprises 100 parts by weight of a monofunctional monomer (A) represented by the following general formula [], 40 to 600 parts by weight of a bifunctional oligomer (B) represented by the following general formula [], and an epoxy resin having an epoxy group. Resin 5-300
The present invention relates to an active energy ray-curable composition containing a photosensitizer as a main component in an amount of 0 to 10% by weight based on all components. (However, in the formula [], R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group, and m represents an integer of 1 to 5.) (However, in the formula [], R ₃ and R ₄ each independently represent a hydrogen atom or a methyl group, and p represents an integer of 2 to 6.) In the present invention, the monomer (A) is a combination of phenol with ethylene oxide or propylene oxide. It is a compound obtained by adding and esterifying acrylic acid or methacrylic acid, and in the general formula [], m is suitably 1 to 5, preferably 1 to 3, and this monomer (A) is a clear liquid with a viscosity of approximately 50-300 cps (25°C).
When a compound in which m is 6 or more is used, the cured film obtained is undesirable because it is soft and brittle. If the amount of monomer (A) used is less than the above-mentioned amount, problems will arise in the adhesion and flexibility of the cured film, and the system will become highly viscous, making it difficult to work in the painting or printing process. On the other hand, if the amount used is too large, the cured film becomes weak and becomes impractical. In the present invention, the oligomer (B) is obtained by reacting phthalic anhydride with a dihydroxyalkyl compound having a hydroxyl group at the end, removing the terminal reactants using a reaction system, and then reacting with (meth)acrylic acid. This dihydroxyalkyl compound having a hydroxyl group at its terminal is a compound obtained by
Any compound may be used as long as it is represented by the general formula HO-( _CH2 ) _-pOH , where p in the general formula is an integer of 2 to 6. When a dihydroxyalkyl compound with p of 7 or more is used, the resulting cured film is weak and has low hardness, which is not suitable. The dihydroxyalkyl compound having a hydroxyl group at the end used in this oligomer (B) includes ethylene glycol, 1,3-propylene glycol,
1.4-butanediol, 1.5-pentanediol,
Mention may be made of 1,6-hexanediol,
Using 1.5-pentanediol or 1.6-hexanediol, n in the above general formula []
When an oligomer (B) whose main component is a compound having an integer of 1 to 4, a number average molecular weight of 700 to 900, and a viscosity (at 25°C) of 400 to 700 cps is used, the viscosity and processing resistance when made into a paint are It is particularly suitable from this point of view. In the present invention, the oligomer (B) is preferably blended in a range of 40 to 600 parts by weight with respect to 100 parts by weight of the above-mentioned monomer (A), and when the blended amount is less than 40 parts by weight, The resulting cured film is
It was not possible to show the excellent elongation characteristic of oligoester diacrylate, and the amount of
If it exceeds 600 parts by weight, the hardness and adhesion of the cured film will decrease, making it unsuitable. The epoxy resin used in the present invention may have one or more, preferably two or more, epoxy groups in one molecule, such as glycidyl ether type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, linear Aliphatic epoxide, alicyclic epoxy resin, etc. can be suitably used. Glycidyl ether type epoxy resins include bisphenol A diglycidyl ether, bisphenol A di-β methyl glycidyl ether, bisphenol F diglycidyl ether, water-added bisphenol A glycidyl ether, and bisphenol A alkylene oxide adduct diglycidyl. There are ethers, novolac glycidyl ethers, polyalkylene glycol diglycidyl ethers, epoxy urethane resins, etc.
Glycidyl ester type epoxy resins include phthalic acid diglycidyl ester and dimer acid diglycidyl ester, glycidylamine type epoxy resins include triglycidyl isocyanurate, etc., and linear aliphatic epoxy resins include epoxidized Examples of alicyclic epoxy resins include polybutadiene and epoxidized soybean oil.
Bis(3.4-epoxy-6-methylcyclohexylmethyl)adipate, 3.4-epoxy-6-methylcyclohexylmethyl, 3.4-epoxy-6
-Methyl cyclohexane carboxylate and the like. This epoxy resin is preferably blended in a range of 5 to 300 parts by weight with respect to 100 parts by weight of the monomer (A), and when the blended amount is less than 5 parts by weight, tin plate, TFS plate, aluminum Adhesion to metal materials such as plates, and coated plates such as alkyd resins, vinyl resins, epoxy resins, acrylic resins, and polyester resins decreases, causing problems in processing resistance such as bendability and punching properties. If more than 300 parts by weight is added, the hardness of the cured film decreases and is not suitable for practical use. In the present invention, when the active light is ultraviolet rays, it is necessary to add a photosensitizer, for example,
Benzoin sensitizers such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, α-chlorobenzoin, α-allylbenzoin, benzophenone, P-methylbenzophenone, P-chlorobenzophenone , benzophenone sensitizers such as Michler's ketone, quinone sensitizers such as anthraquinone and 2-methylanthraquinone, sulfide sensitizers such as phenyl disulfide and tetramethylthiuram monosulfide, thioxanthone, 2-chlor Thioxanthone-based sensitizers such as thioxanthone are used alone or in appropriate combinations. The amount of these photosensitizers is desirably in the range of 0 to 10% by weight based on the total composition. In the present invention, in order to improve the properties of the cured film or to lower the viscosity of the composition, reactive monomers or organic solvents may be added as necessary. For example, 2- Hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, trimethylolpropane mono(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol mono(meth)acrylate, pentaerythritol tri(meth)acrylate, Styrene, vinyltoluene, N-vinylpyrrolidone, 3-phenoxy-2-hydroxypropyl (meth)acrylate, glycidyl (meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol mono(meth)acrylate
Reaction of acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, reaction product of adduct of bisphenol A and alkylene oxide with (meth)acrylic acid, etc. It is possible to blend organic solvents such as monomers or organic solvents such as toluene, xylene, ethyl cellosolve, cellosolve acetate, butyl cellosolve, and cyclohexanone. Furthermore, in the present invention, organic and inorganic pigments, extender pigments, plasticizers, various resins, curing acceleration aids, antifoaming agents, higher fatty acids, stabilizers, etc. may be added as necessary. can. The present invention will be explained below using specific examples. All parts in the examples indicate parts by weight. Production example 1 2 mole ethylene oxide adduct of phenol
72 parts (1 mol) of acrylic acid, 40 mmol of p-toluenesulfonic acid, and 20 mmol of hydroquinone monomethyl ether were added to 182 parts (1 mol), and the mixture was heated for 90 to 90 minutes while stirring while blowing air to prevent gelation.
The reaction was carried out at 100°C for 10 hours, and the reaction was terminated when the oxidation became constant. This product was placed in a separatory funnel, 500 parts of water was added, and water washing was carried out. After repeating this water washing three times to remove unreacted substances, distillation was carried out under reduced pressure (100 mgHg) to obtain monomers. (a) was manufactured. Examples 1 to 5 and Comparative Examples 1 to 3 The compositions shown in Tables 1 and 2 were applied to tin plate, TFS plate, aluminum plate, alkyd resin,
Film thickness for vinyl resin and acrylic resin painted boards
It was painted to have a thickness of 7μ and irradiated at 10 Mrad using a curtain beam type electron beam irradiation device to create a cured film. Regarding this film, adhesion (fifth plate, cellophane adhesive tape peeling), pencil hardness, 180
A temperature bending test was conducted. The results are shown in Table 3.

【table】

【table】

【table】

[Table] × indicates a state in which significant cracking is observed.
Examples 6 to 8 The same compositions as in Examples 1 to 3 plus 4 parts of benzoin ethyl ether (each referred to as Examples 6 to 8) were used and coated in the same manner as in Example 1. Ultraviolet irradiation was carried out using an ozone-free high-pressure mercury lamp (output 160 W/m), placed on a conveyor running at a speed of 5 m/min. A similar test was conducted on this cured film,
The results are shown in Table 4.

【table】

Claims (1)

[Claims] 1 100 parts by weight of a monofunctional monomer (A) represented by the following general formula [], 40 to 600 parts by weight of a bifunctional oligomer (B) represented by the following general formula [], an epoxy group An active energy ray-curable composition containing 5 to 300 parts by weight of an epoxy resin and 0 to 10% by weight of a photosensitizer based on the total components. (However, in the formula [], R ₁ and R ₂ each independently represent a hydrogen atom or a methyl group, and m represents an integer of 1 to 5.) (However, in the formula [], R ₃ and R ₄ each independently represent a hydrogen atom or a methyl group, and p represents an integer of 2 to 6.) 2. A patent characterized in that an aromatic diglycidyl ether type epoxy resin is used. A curable composition according to claim 1.