JP2003313489A - Radiation curable resin composition for coating aluminum material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radiation curable resin composition for coating a metal, especially an aluminum product requiring severe flexibility and hiding properties in a non-solvent system including 100% active components with coating suitability that have been imparted conventionally by the solvent dilution while maintaining film strength, flexibility, hiding properties and the like formed by the conventional polymeric heat curable resin component. <P>SOLUTION: The radiation curable resin composition contains an epoxyacrylate oligomer having an acid group and a urethane acrylate oligomer, acryloylmorpholine, isobornylacrylate and a silane-type coupling agent as essential components. Thus, it is secured that the coating material and the printing ink with excellent coating properties and physical properties are obtained by using this resin composition. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation-curable resin composition coated on an aluminum material, and more specifically, like an aluminum tube, when it is used, it is bent or pressed to remove its contents. TECHNICAL FIELD The present invention relates to a radiation-curable resin composition which provides a coating agent or printing ink adapted to an aluminum product which is required to have flexibility on the assumption that it is repeatedly stretched.

[0002]

2. Description of the Related Art For coating aluminum tubes, a heat-drying and hardening type coating agent containing a large amount of an organic solvent has been conventionally used. After coating, the temperature is kept at around 150 ° C. by using far infrared rays or a gas furnace. For 20 to 30 minutes, the organic solvent is evaporated and a coat film is formed.

[0003]

A large amount of organic solvent is contained in the conventionally used heat-drying and curing type coating agent, and occupational safety and health, work environment, disaster prevention, and environmental protection caused by evaporation of this organic solvent. Problems such as influence are emphasized, and there are many problems such as lengthening of the production line for long-term drying and consumption of a large amount of production energy. An object of the present invention is to provide a radiation curable resin composition that solves these problems. That is, the radiation-curable resin composition of the present invention does not contain an organic solvent, and after being coated on an aluminum tube, it is instantaneously irradiated with radiation by a radiation irradiation device (ultraviolet irradiation device or electron beam irradiation device). It is possible to cure and form a coating film. Therefore, the radiation-curable resin composition of the present invention solves various problems of conventional heat-drying-curable coating agents all at once.

[0004]

DISCLOSURE OF THE INVENTION The present invention is a radiation-curable type which is characterized by containing an epoxy acrylate oligomer and a urethane acrylate oligomer containing an acid group, and acryloylmorpholine, isobornyl acrylate and a silane coupling agent. The resin composition solves the above problems. Further, a photopolymerization initiator, a coloring pigment, a substance capable of imparting surface physical properties and coating suitability can be added to the radiation curable resin composition. Acryloylmorpholine and isobornyl acrylate monomers reduce the viscosity of liquid substances such as epoxy acrylate oligomers and urethane acrylate oligomers, and silane coupling agents combine inorganic aluminum materials with organic coating films. It functions as a surfactant.

Examples of the epoxy acrylate oligomer having an acid group applicable to the present invention include (meth) acrylate group-containing compounds containing a phosphoric acid group, a carboxyl group, a sulfonic acid group and the like. For example, it can be obtained, for example, by acrylating a reaction product of an acid group and bisphenol A glycidyl ether.

The epoxy acrylate oligomer having an acid group used in the present invention has an average molecular weight of 2000 to 300.
The acid value of 0 and the acid value of 20 to 40 mgKOH / g are preferable.

The urethane acrylate oligomer which can be used in the present invention is not particularly limited as long as it is a commercially available urethane acrylate oligomer, but since flexibility is required, a type having an average molecular weight of 2,500 to 10,000 and good surface curability is used. Is preferred. Average molecular weight is 2500
If it is less than the above range, the cured film is so hard that cracks occur in the coated film during bending and the target flexibility cannot be obtained. Further, when the average molecular weight exceeds 10,000, the crosslink density of the cured coating decreases, and thus the chemical resistance decreases.
It is preferable to add 15 to 25 parts by weight of urethane acrylate oligomer to 100 parts by weight of epoxy acrylate oligomer.

In the present invention, acryloylmorpholine and isobornyl acrylate are essential components (hereinafter, this combination is referred to as a vehicle component) of the photopolymerizable monomer to be combined with the above-mentioned acid group-containing epoxy acrylate oligomer and urethane acrylate oligomer. However, the compositional ratio is 50 parts by weight of acryloylmorpholine to 100 parts by weight of epoxy acrylate oligomer.
˜100 parts by weight is preferable, and isobornyl acrylate is preferably 5 to 30 parts by weight.

Further, in the present invention, in addition to acryloylmorpholine and isobonyl acrylate, a photopolymerizable monofunctional monomer and a bifunctional monomer can be added within a range not deteriorating the object of the present invention. Monofunctional monomers include vinyl caprolactam, ethyl carbitol acrylate, dicyclopentynyl acrylate, 2-ethylhexyl acrylate, etc., and bifunctional monomers include 1.6 hexanediol diacrylate, tetraethylene glycol diacrylate, neopentyl acrylate. Examples include diacrylate and tripropylene glycol diacrylate. These photopolymerizable monofunctional monomer and bifunctional monomer can be added in the range of 0 to 20 parts by weight with respect to 100 parts by weight of the vehicle component of the present invention.

The photopolymerization initiator for forming a film of the resin composition of the present invention by ultraviolet curing can be selected from the following compounds. Examples thereof include benzophenones, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, carbonium compounds such as methylbenzoinformate, phosphorus compounds such as monoacylphosphine oxide and bis-acylphosphine oxide, and thioxanthones. Can be used alone or in combination of two or more.
Further, a known sensitizer can be added to accelerate the photopolymerization reaction. As the sensitizer, for example, amine compounds such as triethanolamine and P-dimethylaminobenzoic acid ester, and polymerizable tertiary amines are useful. The amount of the photopolymerization initiator and the sensitizer added is the vehicle component 1 of the present invention.
5 to 20 parts by weight is preferable with respect to 00 parts by weight.

In the present invention, a radiation-curable resin coating agent using the vehicle component (and a photopolymerization initiator in the case of ultraviolet curing) and a pigment used in obtaining a printing ink are generally commercialized. Inorganic and organic color pigments, inorganic and organic extender pigments, and inorganic and organic matte powder pigments can be used. The pigment may be composed of one or a plurality of compounds depending on the desired color and matting degree of the coating agent and the printing ink. Also,
The pigment blending ratio is determined within a range that does not inhibit radiation curing and does not reduce the object of the present invention, and it is preferably used in an amount of 1 to 100 parts by weight based on 100 parts by weight of the vehicle component.

The silane coupling agent used in the present invention is a vinyl group-containing silane system, a (meth) acryl group-containing silane system, an epoxy group-containing silane system, or an amino group-containing silane system, and two or more are contained in one molecule. , Which are different from each other, one of which is an alkoxysilane group (methoxy group, ethoxy group, etc.) that can chemically bond with an inorganic material (metal, glass, etc.) by hydrolysis and then dealcoholation reaction. One is a reactive group (vinyl group, (meth) acrylic group, epoxy group, etc.) that can chemically bond with organic materials (various synthetic resins, etc.).
Amino group, etc.). These silane coupling agents can be used in an amount of 2 to 10% by weight of the solid content component of the radiation curable coating agent and the printing ink.

In the radiation-curable resin composition of the present invention, various antifoaming agents and leveling agents which are generally commercialized and known for the purpose of improving the physical properties of coating films and imparting coating suitability are added, if necessary. Additives such as silicone oil, lubricants, surfactants, pigment dispersants, fluidity regulators, preservatives, thermal polymerization inhibitors, and oxidation polymerization inhibitors can be used.

The material of the material to which the radiation-curable resin composition of the present invention can be applied is a metal, and is particularly excellent in adhesion, flexibility, abrasion resistance, chemical resistance and the like to an aluminum tube.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to composition examples of a white pigment-containing system, which is the most used record for an aluminum tube coat in a composition of an ultraviolet curable resin. The present invention is not limited to this embodiment, and may be used in electron beam curing in a form in which an initiator is excluded from the resin composition of the embodiment, or as other color component-containing or clear protective coat. It can be used without any problems. The radiation-curable composition of the present invention was roll-coated with 100% of the active ingredient without containing an organic solvent, and cured with an ultraviolet irradiation device. Although all of the compounding compositions of Examples and Comparative Examples shown below are the compounds that are dispersed after mixing with a three-roll mill or the like, the pigments may be dispersed by other generally known methods.

Specific examples in the case where the average molecular weight of the epoxy acrylate oligomer containing an acid group used in the present invention is varied and the acid value is slightly changed,
A comparative example is shown. The composition example in which the molecular weight and acid value of the epoxy acrylate oligomer is within the preferred range of the present invention and other compositions are also within the range of the present invention is shown in Example 1, and the molecular weight and acid value of the epoxy acrylate oligomer are changed. Table 1 shows the composition and physical property evaluation results for Comparative Examples 1 to 4 when the content is out of the range.

[0017]

[Table 1]

Samples were epoxy acrylate oligomers containing phosphoric acid groups, and the following five types A to D having different molecular weights and acid values were used. Example 1. Epoxy acrylate oligomer A: average molecular weight 2000, acid value 25 Comparative Example 1. Epoxy acrylate oligomer B: average molecular weight 2000, acid value 10 Comparative example 2. Epoxy acrylate oligomer C: average molecular weight 2000, acid value 50 Comparative Example 3. Epoxy acrylate oligomer D: average molecular weight 800, acid value 25 Comparative Example 4. Epoxy acrylate oligomer E: average molecular weight 800 Acid value 5 As can be seen from Table 1, the required physical properties could not be cleared for the composition outside the preferred range of the present invention.

Example 1 and Comparative Examples 5 and 5 were prepared when the number of parts by weight of the urethane acrylate oligomer was changed to 100 parts by weight of the epoxy acrylate oligomer, and when the average molecular weight of the urethane acrylate oligomer was changed. Table 1 also shows the composition and physical property evaluation results. Example 1. Urethane acrylate A; average molecular weight 5000: about 17 parts by weight (based on 100 parts by weight of epoxy acrylate oligomer) Comparative Example 5. Urethane acrylate A; average molecular weight 5000 about 34 parts by weight (based on 100 parts by weight of epoxy acrylate oligomer) Comparative Example 6. Urethane acrylate oligomer B; average molecular weight 2000 about 17 parts by weight (based on 100 parts by weight of epoxy acrylate oligomer) Comparative Example 7. Urethane acrylate oligomer B; average molecular weight 2000 about 34 parts by weight (based on 100 parts by weight of epoxy acrylate oligomer) Comparative Example 8. Urethane acrylate oligomer C; average molecular weight 20000 about 17 parts by weight (based on 100 parts by weight of epoxy acrylate oligomer) Comparative Example 9. Urethane acrylate oligomer C; average molecular weight 20000 about 34 parts by weight (based on 100 parts by weight of epoxy acrylate oligomer) Comparative Example 10. When no urethane acrylate oligomer is contained As shown in Table 1, neither the composition deviating from the preferred range of the present invention or the comparative example of the composition not containing the essential components of the present invention could satisfy the required physical properties.

Furthermore, the reaction component (alkoxysilane) of the silane coupling agent with the inorganic substance is constant, and the functional group as the other reaction component is changed to a vinyl group, a (meth) acryl group, an epoxy group, or an amino group. An example of the case will be described. Example 1. Example of vinyl group-containing trimethoxysilane 1. (Meth) acrylic group-containing trimethoxysilane Example 3. Example of epoxy group-containing trimethoxysilane 4. In the evaluation of the physical properties of the amino group-containing trimethoxysilane, no difference was observed, which was good, but the resin composition using the amino group-containing coupling agent of Example 4 tended to increase in viscosity over time, and the time was about 1 hour. Then, the coating was out of the proper viscosity range, resulting in poor appearance. This is not suitable for use because it poses a problem during actual manufacturing.

Composition Example 1 containing acryloylmorpholine and isobonyl acrylate, which are essential components of the present invention, and Comparative Example 11 a composition containing no acryloylmorpholine, and Comparative Example 11 containing a composition containing no isobornyl acrylate Table 1 shows the compounding ratio of the components and the evaluation results of physical properties. In the comparative example, insufficient physical properties such as adhesion and flexibility were observed.

Table 2 shows the results of evaluation of physical properties of the radiation curable resin composition of the present invention when the film thickness was changed using the coating agent shown in Example 1 of Table 1. As can be seen from Table 2, the film thickness of 12 to 15 μm has the best physical properties,
When the film thickness is 10 μm or less, the hiding property is poor and the underlying layer is visible, resulting in poor appearance. When the film thickness exceeds 20 μm, internal curing is poor and peeling results.

[0023]

[Table 2]

Table 3 shows the criteria of the physical property evaluation results used in Tables 1 and 2.

[0025]

[Table 3]

The conditions of the coating method and the curing method when conducting the test are as follows. Coating method: Roll coater-Coating speed: 80 lines / minute Setting film thickness: 12 to 15 μm (in the case of Examples and Comparative Examples shown in Table 1) UV curing conditions: 1 metal halide lamp, 120 W / cm output lamp and base Material distance 100 mm Lamp peak intensity 670 mW / cm ² Lamp integrated light intensity 500 mJ / cm ²

Next, the method of evaluating physical properties is as follows. Curability: Check for sticky surface and uncured inside. Adhesion: 1 mm square cross-cut and 24 mm wide Nichiban cellophane tape (registered trademark) was used to check for peeling. Flexibility (Crash resistance): Separate the aluminum tube only on the body part, and drop a 2 kg weight from the height of 450 mm on the tube. When the crushed tube is manually stretched, check for cracks, peeling, floating, etc. of the coating film. Scratch resistance (smudge resistance): (white) Rub the surface of the coated tube with the unpainted aluminum tube plane and the end. At that time, check whether or not a trace remains on the coated surface. Chemical resistance: (white) Expand the coated tube and soak the absorbent cotton with acetone, benzyl alcohol, etc. 0.5
There should be no peeling or exposure of the base after 10 reciprocations under a load of kg / cm ² . Stability: Confirmation of change with time of viscosity of radiation curable resin composition. No significant thickening.

[0028]

The composition according to the present invention has excellent physical properties such as adhesion to aluminum products, flexibility (crush resistance), scratch resistance (smudge resistance) and chemical resistance. Even if you repeatedly bend the printed product or stretch it by applying pressure,
The coating film or the printed film does not peel off, and the initial film state is secured.

Further, the viscosity can be reduced while the curability, flexibility and toughness are ensured, and the ultraviolet curing is excellent in quick-drying and can be applied to high-speed coating and high-speed printing. Therefore, shortening of the production line and reduction of energy consumption can be expected, and all aspects are low in cost and rich in productivity. In addition, since there is no volatilization due to organic solvent, occupational safety and health and working environment are improved, which is useful for health maintenance.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09D 11/10 C09D 11/10 175/16 175/16 183/04 183/04 (72) Inventor Mitsuo Yasuda 2-705-20 Komatsudai, Hanyu-shi, Saitama Hanyu Komatsudai Industrial Park Jujo Chemicals Co., Ltd. Hanyu Technology Center F-term (reference) 4J011 PA47 PB40 PC02 PC08 4J027 AE04 AE05 AG36 AJ01 AJ05 AJ08 BA07 BA13 BA19 CA29 CB10 CC05 CD08 4J038 DB351 DB352 DB371 DB372 DG321 DG322 DL032 FA131 FA132 FA171 FA172 FA251 FA252 FA281 FA282 JC32 KA03 KA07 KA08 KA09 NA24 NA27 PA17 PC02 4J039 AD21 AE04 AE05 AE11 AF03 AF07 BC57 BE01 BE02 BE16 BE25 EA04 EA10 EA45

Claims (2)

[Claims] 1. An epoxy acrylate oligomer and a urethane acrylate oligomer adapted to an aluminum material and containing an acid group, and acryloylmorpholine,
A radiation-curable resin composition comprising isobornyl acrylate and a silane coupling agent as components. 2. A coating obtained by adding a coloring agent such as a pigment and a dye, or a leveling agent and a defoaming agent made of silicone oil or various polymer copolymers to the radiation curable resin composition according to claim 1. Agent or printing ink.