JPH07330836A - Composition and its use - Google Patents

Abstract

PURPOSE:To obtain a composition containing an anionic surfactant, a specific compound, acrylic acid and a light initiator, excellent in the stability of surface state even with the passage of time in antistatic properties, curable under the atmosphere and useful as a protective coating agent, etc., for optical discs. CONSTITUTION:This composition contains (A) an anionic surfactant having (meth)acryloyl group and/or vinyl group, (B) either one compound of formula I to formula III [A is CH2=CHCO or CH=C(CH3)CO], (C) a (meth)acrylic acid ester and (D) a light initiator. Furthermore, succinic acid ester, etc., tetrahydrofurfuryl (meth)acrylate, etc., trimethylolpropane triacrylate, etc., and diethoxy acetophenone, etc., are preferably used as the components A, B, C, and D, respectively.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a protective coating agent,
More specifically, the present invention relates to a protective coating agent which is useful for optical media such as optical discs, which has excellent antistatic properties and surface stability over time.

[0002]

2. Description of the Related Art Conventionally, various types of coating agents for optical media, especially optical discs, have been proposed. However, the coating agents proposed so far have various antistatic properties because they impart antistatic ability. Contains an inhibitor. Examples of the antistatic agent include a surfactant and a metal filler, but there is a problem in stability over time such as bleeding out.

[0003]

The object of the present invention is to provide an excellent antistatic ability by using a reactive anionic surfactant as an antistatic agent, and to use it as a protective coating agent for optical discs. The purpose is to prevent dust and the like from adhering to the disk surface. In addition, by using an antistatic agent that has reactivity with an ultraviolet curable resin, it is possible to avoid contamination of the disk surface due to bleed-out and to provide an ultraviolet curable protective coating agent with excellent surface stability over time. is there.

[0004]

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, the film formed on the surface of the disk has an antistatic function and is less likely to be contaminated by dust. We have completed a UV-curable protective coating agent that cures in the atmosphere with excellent temporal stability of the surface condition of the film in the environment of high temperature and high humidity, which is a durability test condition for optical media.

That is, the present invention provides at least one or more selected from anionic surfactants (A) having a (meth) acryloyl group and / or vinyl group and compounds represented by the formulas (1) to (3). Compound (B) of

[0006]

[Chemical 4]

[0007]

[Chemical 5]

[0008]

[Chemical 6]

A composition containing a (meth) acrylic acid ester (C) and a photoinitiator (D), an ultraviolet-curable coating agent curable in the atmosphere which comprises this composition, and this composition. The present invention relates to a protective coating agent for optical discs.

The present invention will be described in detail below.

Specific examples of the anionic surfactant (A) having a (meth) acryloyl group and / or a vinyl group used in the present invention include, for example, succinic acid ester represented by the formula (4). A salt (for example, Sanyo Kasei Co., Ltd., trade name "Eleminol AS-2H", etc.) or a phosphate ester salt as shown by the formula (5) (for example,
Dai-ichi Kogyo Seiyaku Co., Ltd., trade name "New Frontier A2"
29E "and the like). In the formula (4) or the formula (5), R _{1 to} R ₄ are each a carbon number 1 to
12 substituted or unsubstituted linear or branched alkyl groups are shown.

[0012]

[Chemical 7]

[0013]

[Chemical 8]

The addition amount of the surfactant (A) of the present invention is 0.1% by weight or more and 15% by weight or less, preferably 0.2% by weight or more and 10% by weight or less, more preferably 0.5% by weight in the composition. It is at least 8% by weight. Addition amount is 0.1
If the addition amount is less than wt%, the antistatic ability is difficult to be imparted, and if added in excess of 15 wt%, the stability of the film over time, such as bleeding out of unreacted components, may decrease.

Equations (1) to (1) that can be used in the present invention
Examples of the compound (B) represented by (3) include tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, and alkyldiol di (meth) acrylate. In the formula (3), an alkyl group R
Is a substituted or unsubstituted, straight-chain or branched-chain alkyl group having 4 to 10 carbon atoms, specifically, a butyl group,
Examples thereof include hexyl group and neopentyl group. Further, A at both ends may be the same group or different groups.

The amount of the compound (B) added is 0.5 in the composition.
% To 50% by weight, preferably 1 to 4% by weight
It is 5% by weight or less, more preferably 2% by weight or more and 30% by weight or less. If the addition amount is less than 0.5% by weight, the uniform mixing property of the resin composition is deteriorated, and if the addition amount exceeds 50% by weight, the three-dimensional crosslinked structure of the film may be difficult to be formed.

The protective coating agent in the present invention includes the reactive anionic surfactant (A) having at least one unsaturated group in the molecule and the compound represented by the formulas (1) to (3). It is composed of at least one or more compounds (B) selected from the above, (meth) acrylic acid ester (C) and photoinitiator (D), and other additives may be added if necessary.

The (meth) acrylic acid ester (C) in the present invention is a monofunctional, bifunctional, and trifunctional or higher functional acrylic and / or methacrylic acid ester.

Examples of the monofunctional acrylic and / or methacrylic acid ester that can be used in the present invention include phenoxyethyl acrylate, isoamyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxy-3-phenoxy. Examples include propyl acrylate.

The addition amount of the monofunctional acrylic and / or methacrylic acid ester is 0% by weight or more and 50% by weight or less,
Preferably, it can be used in an amount of 5% by weight or more and 45% by weight or less. When it is used in an amount of more than 50% by weight, it may be difficult to form a three-dimensional crosslinked structure of the cured film.

A typical example of the bifunctional acrylic or / and methacrylic acid ester that can be used in the present invention is polyethylene glycol (PEG) # 40.
Examples thereof include 0 diacrylate, PEG # 600 diacrylate, neopentyl glycol diacrylate, ethylenoxide-modified bisphenol A diacrylate, and hydrogenated dicyclopentadienyl diacrylate.

The addition amount of the bifunctional acrylic and / or methacrylic acid ester is 5% by weight or more and 50% by weight or less, preferably 8% by weight or more and 45% by weight or less. 5
When the concentration is lower than 50% by weight, the adhesion to the polycarbonate substrate may not be exhibited, and when it is added in excess of 50% by weight, the protective property of the film may be deteriorated.

Typical examples of trifunctional or higher functional acrylic and / or methacrylic acid esters that can be used in the present invention include trimethylolpropane triacrylate, ethylene oxide-modified trimethylolpropane triacrylate, pentaerythritol triacrylate and penta. Examples thereof include erythritol tetraacrylate and dipentaerythritol hexaacrylate.

The amount of trifunctional or higher functional acrylic and / or methacrylic acid ester added is from 5% by weight to 80% by weight.
Hereafter, the range is preferably 20% by weight or more and 70% by weight or less. If it is less than 5% by weight, the hardness and scratch resistance required for protection may be lowered, and if it exceeds 80% by weight, the film shrinkage ratio upon curing the coating agent may be high.

The acrylic and / or methacrylic acid ester used in the present invention may be of one type or a combination of two or more types.

As the photoinitiator (D) in the present invention,
Examples thereof include acetophenone-based, benzoin ether-based, thioxanthone-based, and benzophenone-based photoinitiators. Moreover, you may add a hydrogen donor as needed.

The photoinitiator (D) that can be used in the present invention is, for example, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenylketone, or 2
-Methyl-2-morpholino (4-thiomethylphenyl)
Propane 1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, benzoin methyl ether, benzoinetyl ether, benzoyl isopropyl ether, benzoyl isobutyl ether, benzophenone, 3,3 ', 4 , 4'-tetra (t-butylperoxycarbonyl) benzophenone,
Methyl o-benzoylbenzoate, 4,4'-dichlorobenzophenone, 4-phenylbenzophenone, 4-benzoyl-4'-methylphenyl sulfide, hydroxybenzophenone, 2-isopropylthioxanthone,
Examples include 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and 2,4-dichlorothioxanthone.

Examples of hydrogen donors usable in the present invention include triethanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, and 4-dimethylaminobenzoate. 2-ethylhexyl acid, benzoic acid (2
-Dimethylamino) ethyl, 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone, 4-dimethylaminoacetophenone and the like can be exemplified.

The amount of the photoinitiator added in the present invention is 0.1% by weight or more and 15% by weight or less based on the total amount of the photocurable resin and the additive when the photocurable resin or the additive is used. , And preferably 1% by weight or more and 10% by weight or less. More preferably, it is 2% by weight or more and 8% by weight or less. If added in excess of 15% by weight, unreacted photoinitiator during curing may reduce the stability of the film over time. Further, if the addition amount is less than 0.1% by weight, the curability is remarkably deteriorated, which is not practical.

A protective coating agent can be obtained by polymerizing the above ultraviolet curable resin composition using a high pressure mercury lamp. It can be inferred from the light emission spectrum pattern that an ultra-high pressure mercury lamp, a metal halide lamp, etc. can be used as an ultraviolet ray source other than the high pressure mercury lamp.

Further, for the purpose of imparting uniform coating properties and suppressing the occurrence of coating defects such as orange peels and craters, one or more leveling agents can be added to the coating agent. Silicone-based surfactants and fluorine-based surfactants are generally known as leveling agents, and they can be used within a range that does not impair the performance of a coating agent intended for them.

The integrated quantity of light when the ultraviolet irradiation in the present invention, 200 mJ / cm ² or more 1500 mJ / cm ² or less,
Preferably 300 mJ / cm ² or more and 1000 mJ / c
m ² or less. If it is less than 200 mJ / cm ² , the curability may be poor, and if it exceeds 1500 mJ / cm ² , the cured film may shrink.

[0033]

The UV curable resin composition obtained by using the photoinitiator system of the present invention thus obtained is photocured under predetermined conditions to enhance the antistatic property of the substrate surface and to coat the coating surface. Is a protective coating agent having excellent stability over time.

[0034]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples.

Example 1 As surfactant (A), Sanyo Kasei Co., Ltd., trade name "Eleminol AS-2H" 20 g, as compound (B), tetrahydrofurfuryl acrylate 130 g,
As (meth) acrylic acid ester (C), 350 g of pentaerythritol triacrylate, 350 g of polyethylene glycol (PEG) # 400 diacrylate,
40 g of hydrogenated dicyclopentadienyl diacrylate,
130 g of 1,6-hexanediol diacrylate, methylbenzoyl formate 3 as a photoinitiator (D)
0 g, and a silicone-based paint additive as a leveling agent (Shin-Etsu Chemical Co., Ltd., trade name "KP-306")
1 g was well mixed and dissolved to obtain a resin composition of the present invention (protective coating agent for optical disc).

After 1.5 g of this resin composition was dispensed onto the non-grooved surface of a polycarbonate magneto-optical disk substrate having a diameter of 90 mm, a thickness of 10 μm was obtained by spin coating.
m, which was exposed and cured using a 120 W / cm high pressure mercury lamp. The above process is 23 ± 1
It was performed in an environment of 50 ° C. and 50 ± 3% RH.

The exposure was carried out from a height of 100 mm on the film so that the integrated irradiation dose of ultraviolet rays was 650 mJ / cm ² (λ = 365 nm).

The abrasion resistance test was evaluated by visually observing the state of the rubbed surface using a steel wool # 0000 under a load of 100 g under a fluorescent lamp, and the pencil hardness was measured by J
Performed according to ISK-6911. After the disk was stored for 2000 hours in an environment of a temperature of 80 ° C. and a humidity of 85% RH, the surface of the film was observed with an optical microscope. The test results are shown in Table 1.

Example 2 As a surfactant (A), Sanyo Kasei Co., Ltd., trade name "eleminol AS-2H" 20 g, as compound (B), tetrahydrofurfuryl acrylate 130 g,
As (meth) acrylic acid ester (C), 350 g of pentaerythritol triacrylate, 350 g of polyethylene glycol (PEG) # 400 diacrylate,
40 g of hydrogenated dicyclopentadienyl diacrylate,
130 g of 1,6-hexanediol diacrylate, methylbenzoyl formate 3 as a photoinitiator (D)
0 g, and a silicone-based paint additive as a leveling agent (Shin-Etsu Chemical Co., Ltd., trade name "KP-306")
1 g was well mixed and dissolved to obtain a resin composition of the present invention (protective coating agent for optical disc).

A substrate coated with this resin composition was prepared in the same manner as in Example 1, and a film test was conducted in the same manner as in Example 1, and an environmental preservation test was conducted to determine the surface condition with an optical microscope. Observed at. The results are shown in Table 1.

Example 3 As a surfactant (A), manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name "New Frontier A229E" 30 g, and as compound (B), tetrahydrofurfuryl acrylate 1
30 g, as (meth) acrylic acid ester (C), 350 g of dipentaerythritol hexaacrylate, 350 g of polyethylene glycol (PEG) # 400 diacrylate, 40 g of hydrogenated dicyclopentadienyl diacrylate, 1,6-hexanediol diacrylate 1
30 g, methylbenzoyl formate 30 g as a photoinitiator (D), and a silicone-based coating additive as a leveling agent (manufactured by Shin-Etsu Chemical Co., Ltd., trade name “KP-
306 ") 1 g was thoroughly mixed and dissolved to obtain a resin composition (protective coating agent for optical disk) of the present invention.

Using this resin composition, a coated substrate was prepared in the same manner as in Example 1, the film test was conducted in the same manner as in Example 1, and the environment preservation test was conducted to determine the surface condition with an optical microscope. Observed at. The results are shown in Table 1.

Example 4 As a surfactant (A), manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name "New Frontier A229E" 30 g, and as a compound (B), tetrahydrofurfuryl acrylate 1
30 g, as (meth) acrylic acid ester (C), 350 g of dipentaerythritol hexaacrylate, 350 g of polyethylene glycol (PEG) # 400 diacrylate, 40 g of hydrogenated dicyclopentadienyl diacrylate, 1,6-hexanediol diacrylate 1
30 g, 2-hydroxy-2- as a photoinitiator (D)
70 g of methyl-1-phenylpropan-1-one and 1 g of a silicone-based coating additive (trade name “KP-306” manufactured by Shin-Etsu Chemical Co., Ltd.) as a leveling agent were mixed and dissolved well, and the resin of the present invention A composition (protective coating agent for optical disk) was obtained.

A substrate coated with this resin composition was prepared in the same manner as in Example 1, the film was tested in the same manner as in Example 1, and the environment preservation test was carried out to determine the surface condition with an optical microscope. Observed at. The results are shown in Table 1.

Comparative Example 1 As a surfactant (A), Sanyo Kasei Co., Ltd., trade name "Eleminol AS-2H" 30 g, as (meth) acrylic acid ester (C), pentaerythritol triacrylate 400 g, polyethylene glycol (PE
G) 400 g of # 400 diacrylate, 200 g of 2-hydroxyethyl acrylate, as a photoinitiator (D),
Mix well with 30 g of methylbenzoyl formate and 1 g of a silicone-based paint additive (trade name “KP-306” manufactured by Shin-Etsu Chemical Co., Ltd.) as a leveling agent.
Although it was dissolved, a gelling component was deposited and a uniform resin composition (protective coating agent for optical disc) could not be prepared.

Comparative Example 2 A resin composition (protective coating agent for optical disk) was obtained by mixing and dissolving in the same manner as in Example 1 except that AS-2H was omitted from Example 1. Using this, a coated substrate was prepared in the same manner as in Example 1, a film test was conducted in the same manner as in Example 1, an environmental preservation test was conducted, and the surface condition was observed with an optical microscope. The results are shown in Table 1.

[0047]

[Table 1]

Claims (3)

[Claims] 1. An anionic surfactant (A) having a (meth) acryloyl group and / or a vinyl group, and at least one compound (B) selected from compounds represented by formulas (1) to (3). , [Chemical 1] [Chemical 2] [Chemical 3] A composition comprising a (meth) acrylic acid ester (C) and a photoinitiator (D). 2. An ultraviolet curable coating agent comprising the composition according to claim 1, which is curable in the atmosphere. 3. A protective coating agent for an optical disk, which is curable in the atmosphere and comprises the composition according to claim 1.