JP3465452B2 - UV curable resin composition and coating agent containing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition which is cured by irradiation with ultraviolet rays, and is particularly suitable for use as a coating agent for polyester film-coated squeezed cans, which has excellent adhesiveness,
The present invention relates to an ultraviolet-curable resin composition having excellent lubricity, retort resistance, coating film hardness, and workability.

[0002]

2. Description of the Related Art A resin composition which is cross-linked and cured in a short time by irradiation with ultraviolet rays has hitherto been composed of a cationic polymerization composition using a cationic initiator and an epoxy resin, and a resin having a radical initiator and an unsaturated bond. The radical polymerization composition used was mainly. As a cationic polymerization type ultraviolet curable resin composition, in order to improve the physical properties of the cured coating film obtained, it has been studied to use an epoxy resin and another compound in combination, for example, an ultraviolet curable resin containing an epoxy resin and a polyester resin. Type resin composition is Japanese Patent Publication No. 2-30326
However, lubricity, retort resistance, coating film hardness, and workability have not been sufficiently obtained.

Further, as a composition containing a silicone composition, an ultraviolet-curable resin composition containing an epoxy silicone and a polyol (JP-A-3-128975), an epoxy resin and a polysiloxane having a hydroxyalkyl group are included. Ultraviolet curable liquid coating composition (JP-A-59-202264), resin composition for optical three-dimensional molding containing an epoxy resin and a functional group compatible with it, and optical three-dimensional molding method using the same (JP-A-7- 156267), polyepoxy polysiloxane and polyepoxide,
And a UV-curable silicone release composition containing a compatibilized monofunctional epoxide (Japanese Patent Laid-Open No. 7-500377), and a photopolymerizable alicyclic compound containing an alicyclic epoxy-functional siloxane in an organic alicyclic polyepoxide A method for accelerating curing of an epoxy composition (Japanese Patent Publication No. 6-89109) is disclosed. However, these compositions are insufficient in terms of adhesion, retort resistance, and processability.

[0004]

An object of the present invention is to provide an ultraviolet-curable resin composition which gives a coating film having excellent adhesion, lubricity, retort resistance, coating hardness and workability to plastic films and metals. Is provided.

[0005]

The present invention provides an epoxy compound (A) which is liquid at room temperature, and a polyorganosiloxane (B) represented by the following general formula (I) having an alicyclic epoxy functional group at both ends. (In the formula, R is a 3,4-epoxycyclohexyl group, and n is an integer of 10 to 40.) and a photocationic polymerization initiator (C) are provided, and an ultraviolet curable resin composition is provided. The present invention further provides a coating agent containing the ultraviolet curable resin composition.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy compound (A) which is liquid at room temperature in the present invention is a compound having at least one epoxy group, which is a conventionally known alicyclic epoxy compound,
Aliphatic epoxy compounds and aromatic epoxy compounds can be used alone or in combination depending on the required performance, but at least 50% by weight of alicyclic epoxy compounds can be used because of the rapid curability of ultraviolet rays. It is preferable to contain. As the alicyclic epoxy compound, those containing cyclohexene oxide or cyclopentene oxide in its molecular structure are preferably used.

Specific examples of the alicyclic epoxy compound will be given below.

[Chemical 1]

[0008]

[Chemical 2]

[0009]

[Chemical 3]

[0010]

[Chemical 4]

Examples of the aliphatic epoxy compound include polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether and trimethylolpropane triglycidyl ether. Examples of the aromatic epoxy compound include cresol novolac epoxy resin and bisphenol type epoxy resin.

The polyorganosiloxane (B) having an alicyclic epoxy functional group at both ends is represented by the following general formula (I). R in the general formula (I) is required to be a 3,4-epoxycyclohexyl group because of its rapid curability by ultraviolet rays.

The polyorganosiloxane (B) is
It is important to have cycloaliphatic epoxy functional groups at both ends. Those having only one end or one alicyclic epoxy functional group in the side chain have only one functional group involved in the reaction, and therefore the polyorganosiloxane skeleton is detached by retort treatment or the like, and the lubricity is improved. descend. Further, those having a large number of alicyclic epoxy functional groups in the side chain are incorporated in the cured product, so the lubricity does not decrease due to immersion treatment with boiling water, etc. Is increased, and as a result, the hardness of the coating film is increased, resulting in insufficient adhesion and workability. For the above reasons, the present invention uses the polyorganosiloxane (B) having highly reactive alicyclic epoxy functional groups at both ends.

It is necessary that n in the general formula (I) is in the range of an integer of 10 to 40, preferably 20 to 40. When n is less than 10, the amount of polyorganosiloxane is small, and thus the lubricity, adhesion, retort resistance, and workability are unavoidably deteriorated. Further, when n exceeds 40, the amount of polyorganosiloxane increases, so that the coating film hardness decreases, and the compatibility with the epoxy compound (A) and the photocationic polymerization initiator (C) decreases and separation occurs. Causes problems such as. Specific examples of the polyorganosiloxane (B) represented by the general formula (I) having an alicyclic epoxy group at both ends include X22-169AS (n
= 10, manufactured by Shin-Etsu Chemical Co., Ltd., X22-169A (n =
20, manufactured by Shin-Etsu Chemical Co., Ltd., X22-169B (n = 4)
0, manufactured by Shin-Etsu Chemical Co., Ltd.).

The polyorganosiloxane (B) having an alicyclic epoxy functional group at both ends is blended within the range of 0.1 to 20 parts by weight with respect to 100 parts by weight of the epoxy compound (A) which is liquid at room temperature. Preferably. The compounding amount is 0.
If it is less than 1 part by weight, the lubricity, adhesion, retort resistance, and processability are unavoidably deteriorated, and if it exceeds 20 parts by weight, the compatibility with the epoxy compound (A) and the photocationic polymerization initiator (C) is improved. It tends to worsen and the adhesiveness also tends to decrease.

The cationic photopolymerization initiator (C) is an initiator that releases a substance that initiates cationic polymerization upon irradiation with ultraviolet rays, and contains an epoxy compound (A) which is liquid at room temperature and an alicyclic epoxy functional group at both ends. It is preferable that the content is 0.5 to 30% by weight, preferably 2 to 20% by weight, based on the total weight of the contained polyorganosiloxane (B). By blending within this range, it is possible to obtain a cured coating film with good adhesion to plastic films and metals, lubricity, retort resistance, coating film hardness, and processability.

As the photocationic polymerization initiator (C), an aryldiazonium salt (for example, P-33 (manufactured by Asahi Denka Kogyo Co., Ltd.)), an aryliodonium salt, an arylsulfonium salt (for example, FC-509 (manufactured by 3M Co.)) are used. , UVE1
014 (manufactured by GE), UVI-6974, UVI-
6970, UVI-6990, UVI-6950 (manufactured by Union Carbide Co.), SP-170, SP-150.
(Manufactured by Asahi Denka Kogyo Co., Ltd.), allene-ion complex (for example,
CG-24-61 (made by Ciba-Geigy) is mentioned.

The UV curable resin composition of the present invention may contain other conventional components, if necessary, such as organic or inorganic pigments, extender pigments, dyes, organic solvents, as long as the purpose is not impaired.
By blending with a coating additive such as a dispersion aid, a leveling agent, a crater, a surfactant, an antifoaming agent, a slip agent, an ultraviolet sensitizer, a reactive or non-reactive diluent,
A coating is obtained.

The ultraviolet curable resin composition of the present invention and the coating agent containing the same include polyethylene terephthalate (hereinafter abbreviated as "PET") film, polyethylene naphthalate film, nylon film, plastic film such as vinyl chloride film, iron, On the surface of metal such as aluminum, plated steel plate, tin-free steel, stainless steel, etc., a usual coating method, for example, roll coating,
It can be applied by gravure coating, gravure offset coating, curtain flow coating, reverse coating, screen printing, spraying and dipping. The thickness of the cured coating film is about 0.5 to 50 μm, preferably 1 to 20 μm
The range is appropriate.

The ultraviolet-curable resin composition of the present invention and the coating agent containing the same can be easily cured at room temperature in a short time by irradiating with ultraviolet rays. As the light source of this ultraviolet ray, a light source containing light with a wavelength in the range of 200 to 450 nm can be usually used, for example, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a xenon lamp, a carbon arc lamp and the like. The coating agent of the present invention can be suitably used particularly for coating a polyester film-coated squeeze can.

[0021]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples without departing from the technical idea of the present invention. In addition,
In the examples, "part" means "part by weight" and "%" means "% by weight"
Represents

Example 1 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 100 parts (“UVR-6110” manufactured by Union Carbide Co.) having alicyclic epoxy functional groups at both ends. Polyorganosiloxane 5 parts (Shin-Etsu Chemical Co., Ltd. "X22-169AS") Photocationic polymerization initiator 6 parts (Union Carbide Co. "UVI-6990") Surfactant (Nippon Unicar "L-7604") Paint 1 was prepared by mixing 1 part and stirring. This is thickness 30
100 μm PET on 0 μm tin-free steel plate
Material laminated with film (hereinafter referred to as "PET / TF
Abbreviated as S]. ) On PET film, and thickness 300
It was coated on an aluminum plate of μm to a film thickness of 7 μm, and 10 m under one high pressure mercury lamp of 80 W / cm each.
It was passed at a speed of / min to cure the coating film.

Example 2 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 100 parts (“UVR-6110” manufactured by Union Carbide Co.) Having alicyclic epoxy functional groups at both ends. Polyorganosiloxane 5 parts (Shin-Etsu Chemical Co., Ltd. "X22-169A") Photocationic polymerization initiator 6 parts (Union Carbide Co. "UVI-6990") Surfactant (Nippon Unicar "L-7604") Paint 2 was prepared by mixing 1 part and stirring. This is Example 1
The coating method was applied in the same manner as in, and the coating film was cured.

Example 3 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 100 parts (“UVR-6110” manufactured by Union Carbide Co.) Having an alicyclic epoxy functional group at both ends. Polyorganosiloxane 5 parts (Shin-Etsu Chemical Co., Ltd. "X22-169B") Photocationic polymerization initiator 6 parts (Union Carbide Co. "UVI-6990") Surfactant (Nippon Unicar "L-7604") One part was mixed and stirred to prepare coating material 3. This is Example 1
The coating method was applied in the same manner as in, and the coating film was cured.

Example 4 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 100 parts (“UVR-6110” manufactured by Union Carbide Co.) having alicyclic epoxy functional groups at both ends. Polyorganosiloxane 0.1 part (Shin-Etsu Chemical Co., Ltd. "X22-169B") Photocationic polymerization initiator 6 parts (Union Carbide Co., "UVI-6990") Surfactant (Nippon Unicar "L-7604" ]) 1 part was mixed and stirred to prepare coating material 4. This is Example 1
The coating method was applied in the same manner as in, and the coating film was cured.

Example 5 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 100 parts (“UVR-6110” manufactured by Union Carbide Co.) Having an alicyclic epoxy functional group at both ends. Polyorganosiloxane 20 parts (Shin-Etsu Chemical Co., Ltd. "X22-169B") Photocationic polymerization initiator 6 parts (Union Carbide Co. "UVI-6990") Surfactant (Nippon Unicar "L-7604") One part was mixed and stirred to prepare coating material 5. This is Example 1
The coating method was applied in the same manner as in, and the coating film was cured.

[Example 6] 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 70 parts ("UVR-6110" manufactured by Union Carbide Co.) bisphenol A type epoxy resin 30 parts (oiled shell Epoxy Co., Ltd. "Epicoat 828") Polyorganosiloxane having alicyclic epoxy functional groups at both ends 5 parts (Shin-Etsu Chemical Co., Ltd. "X22-169B") Photocationic polymerization initiator 6 parts (Union Carbide Co. " UVI-6990 ") 1 part of a surfactant (" L-7604 "manufactured by Nippon Unicar Co., Ltd.) was mixed and stirred to prepare a coating material 6. This is Example 1
The coating method was applied in the same manner as in, and the coating film was cured.

Example 7 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 90 parts (“UVR-6110” manufactured by Union Carbide) ε-caprolactone-modified bifunctional alicyclic epoxy resin 10 parts ("Celoxide 2085" manufactured by Daicel Chemical Industries, Ltd.) Polyorganosiloxane having an alicyclic epoxy functional group at both ends 5 parts ("X22-169B" manufactured by Shin-Etsu Chemical Co., Ltd.) 6 parts photocationic polymerization initiator (Union -Carbide "UVI-6990") 1 part of surfactant (Nippon Unicar "L-7604") was mixed and stirred, and the coating material 7 was produced. This is Example 1
The coating method was applied in the same manner as in, and the coating film was cured.

Example 8 Bis- (3,4-epoxycyclohexyl) adipate 100 parts ("UVR-6199" manufactured by Union Carbide) 5 parts polyorganosiloxane having alicyclic epoxy functional groups at both ends ( Shin-Etsu Chemical Co., Ltd. "X22-169B") Photocationic polymerization initiator 6 parts (Union Carbide Co. "UVI-6990") Surfactant (Nippon Unicar "L-7604") 1 part is mixed. Stirring was performed to prepare paint 8. This is Example 1
The coating method was applied in the same manner as in, and the coating film was cured.

Example 9 Bis- (3,4-epoxycyclohexyl) adipate 90 parts ("UVR-6199" manufactured by Union Carbide) 10 parts bisphenol A type epoxy resin (Epicoat 828 manufactured by Yuka Shell Epoxy Co., Ltd.) ]) Polyorganosiloxane having alicyclic epoxy functional groups at both ends 5 parts (Shin-Etsu Chemical Co., Ltd. "X22-169B") Photocationic polymerization initiator 6 parts (Union Carbide "UVI-6990") Interface 1 part of an activator (“L-7604” manufactured by Nippon Unicar Co., Ltd.) was mixed and stirred to prepare a coating material 9. This is Example 1
The coating method was applied in the same manner as in, and the coating film was cured.

Comparative Example 1 A coating material 10 was prepared in the same manner as in Example 3 except that the polyorganosiloxane having an alicyclic epoxy functional group at both ends was omitted. This was applied in the same manner as in Example 1 to cure the coating film.

Comparative Example 2 A coating material 11 was prepared in the same manner as in Example 6 except that the polyorganosiloxane having an alicyclic epoxy functional group at both ends was removed. This was applied in the same manner as in Example 1 to cure the coating film.

Comparative Example 3 A coating material 12 was prepared in the same manner as in Example 7 except that the polyorganosiloxane having an alicyclic epoxy functional group at both ends was omitted. This was applied in the same manner as in Example 1 to cure the coating film.

Comparative Example 4 A coating material 13 was prepared in the same manner as in Example 9 except that the polyorganosiloxane having an alicyclic epoxy functional group at both ends was removed. This was applied in the same manner as in Example 1 to cure the coating film.

[Comparative Example 5] 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 100 parts ("UVR-6110" manufactured by Union Carbide Co.) Poly having an alicyclic epoxy group in the side chain. Siloxane 5 parts (Shin-Etsu Chemical Co., Ltd. "KF-102") Photocationic polymerization initiator 6 parts (Union Carbide Co., "UVI-6990") Surfactant (Nippon Unicar "L-7604") 1 part Were mixed and stirred to prepare a coating material 14. This was applied in the same manner as in Example 1 to cure the coating film.

Comparative Example 6 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 100 parts (“UVR-6110” manufactured by Union Carbide Co.) Poly having an alicyclic epoxy group in the side chain. Siloxane 5 parts (Shin-Etsu Chemical Co., Ltd. "KF-103") Photocationic polymerization initiator 6 parts (Union Carbide Co. "UVI-6990") Surfactant (Nippon Unicar "L-7604") 1 part Were mixed and stirred to prepare coating material 15. This was applied in the same manner as in Example 1 to cure the coating film.

Comparative Example 7 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 100 parts ("UVR-6110" manufactured by Union Carbide) 5 parts polysiloxane having glycidyl groups at both ends (Shin-Etsu Chemical Co., Ltd. "X-22-163B" Photocationic polymerization initiator 6 parts (Union Carbide Co. "UVI-6990") Surfactant (Nippon Unicar "L-7604") 1 part Then, the mixture was stirred to prepare a coating material 16. The coating material 16 was applied in the same manner as in Example 1 to cure the coating film.

Comparative Example 8 3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate 100 parts ("UVR-6110" manufactured by Union Carbide) 5 parts polysiloxane having a glycidyl group at one end (Shin-Etsu Chemical Co., Ltd. "X-22-173B") Photocationic polymerization initiator 6 parts (Union Carbide Co. "UVI-6990") Surfactant (Japan Unicar Co. "L-7604") 1 part A paint 17 was prepared by mixing and stirring. This was applied in the same manner as in Example 1 to cure the coating film.

The coating films obtained in Examples 1 to 9 and Comparative Examples 1 to 8 were evaluated for adhesion, lubricity, retort resistance, pencil hardness and workability. The evaluation results are shown in Table 1. The evaluation was performed as follows. (1) Adhesion property Based on JIS K5400, 100 goggles and the number of goggles in which the coating film did not come off were shown by a cellotape peeling test. (2) Lubricating surface property measuring instrument ("HEIDON-14" manufactured by Shinto Scientific Co., Ltd.)
Was used to measure the dynamic friction coefficient at 25 ° C. and 50% RH under the conditions of a load of 200 g, a ball indenter φ10 mm, and a moving speed of 100 mm / min. The same measurement was performed on the cured coating film after the treatment with boiling water for 30 minutes. ○ -Dynamic friction coefficient less than 0.1 △ -Dynamic friction coefficient 0.1 or more and less than 0.2 × -Dynamic friction coefficient 0.2 or more

(3) The retort resistant coated plate was treated in steam at high temperature and high pressure (125 ° C.) for 30 minutes, and the whitening and adhesion of the coating film were evaluated. (4) Pencil hardness Based on JIS K5400, Mitsubishi pencil "Uni" at room temperature
The maximum hardness that the coating film peeled off and did not reach the base was evaluated. (5) Workability (evaluated by the coating film applied to the aluminum plate) Using a 1/2 inch rod in a DuPont impact tester,
A weight of 500 g was dropped from a height of 50 cm from the back side of the coating film surface, and cracks generated in the coating film were visually evaluated. ○ -No abnormality △ -Slightly cracked × -Cracked on the entire surface

[0041]

[Table 1]

[0042]

According to the present invention, an ultraviolet curable resin composition suitable for vehicles such as varnishes, paints and inks was obtained. The ultraviolet curable resin composition of the present invention and the coating agent containing the same have excellent adhesion to plastic films and metals, retort resistance, lubricity, coating film hardness, and processability.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) C08G 59/00-59/72 C08L 63/00-63/10 C09D 163/00-163/10

Claims (5)

(57) [Claims] 1. An epoxy compound (A) which is liquid at room temperature and a polyorganosiloxane (B) represented by the following general formula (I) having an alicyclic epoxy functional group at both ends. (In the formula, R is a 3,4-epoxycyclohexyl group, and n is an integer of 10 to 40.) and a photocationic polymerization initiator (C) are contained in the ultraviolet-curable resin composition. 2. The ultraviolet curable resin composition according to claim 1, wherein the epoxy compound (A) which is liquid at room temperature contains at least 50% by weight of an alicyclic epoxy compound. 3. An epoxy compound (A) 100 which is liquid at room temperature.
With respect to parts by weight, 0.1 to 20 parts by weight of a polyorganosiloxane (B) having an alicyclic epoxy functional group at both ends, and a photocationic polymerization initiator (C) of (A) and (B) are used. The ultraviolet-curable resin composition according to claim 1 or 2, characterized in that it is contained in an amount of 0.5 to 30% by weight based on the total weight. 4. A coating agent containing the ultraviolet curable resin composition according to claim 1. 5. The coating agent according to claim 4, which is used for coating a polyester film-coated squeeze can.