JPH08313704A - Resin for antireflection film - Google Patents

Abstract

PURPOSE: To provide a resin for a thin film formed by coating on the surface of glass, plastic, etc., and excellent in antireflection effect to light. CONSTITUTION: This resin contains a copolymer obtd. by cationic- or anionic- polymerizing a compd. having an epoxy group and a fluoroalkyl group in one molecule with a compd. having an epoxy group and a hydrolyzable silyl group in one molecule. The copolymer is excellent in chemical resistance because the principal chain consists of ether bonds, high hardness is ensured by a dehydration condensation reaction of hydrolyzable silyl groups and a film excellent in adhesion to a substrate can be formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is applied to the surface of a substrate such as glass or transparent plastic to reduce the surface reflection of the substrate, improve visibility and effectively utilize visible light energy. The present invention relates to a resin for an antireflection film, which is useful for realizing The resin for an antireflection film of the present invention is applied to a cathode ray tube of a television, a front glass of a picture, a showcase, a glass plate, a spectacle lens, etc., and a thin film produced is a glare or glare due to reflection of sunlight or illumination light, or surroundings. It is effective to prevent the transparency and visibility from being impaired due to the reflection of the landscape.

[0002]

_2. Description of the Related Art Conventionally, as an antireflection coat, a method of forming an MgF ₂ film by vapor deposition and further baking it, and hydrolyzing a titanium-containing organic metal compound and a silicon-containing organic compound to form a TiO ₂ film and a SiO ₂ film. A method of forming a multi-layer coat composed of a film is known. However, in the case of MgF ₂ vapor-deposited film, adhesion is small, hardness and scratch resistance are low, and since it is restricted by vapor deposition equipment, it is difficult to coat large articles, so glass products must be baked. In addition, since it cannot be baked on a plastic product, it was not a practical coating film.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to prevent the above problems by forming an anti-reflection coating which is industrially advantageous and has excellent adhesion to a substrate and excellent durability. It is to provide a resin for an antireflection film for forming a film. The present inventors have found that an epoxy polymer having a fluoroalkyl group and an alkoxysilyl group as a side chain easily forms a crosslinked structure with moisture in the air to form a hard coating film having excellent adhesion, and the coating film Since it has a very low refractive index, it was found that the antireflection effect was high, and the present invention was completed.

[0004]

Means for Solving the Problems The present invention uses a mixture of a compound having an epoxy group and a fluoroalkyl group in one molecule and a compound having an epoxy group and a hydrolyzable silyl group in one molecule as a cation, or Provided is a resin composition for an antireflection film, which comprises a copolymer obtained by anionic polymerization.

Examples of the compound having an epoxy group and a fluoroalkyl group in one molecule constituting the present invention include 3-perfluorohexyl-1,2 epoxypropane, 3-perfluorooctyl-1,2-epoxypropane, 3-perfluorodecyl-1,2-epoxypropane, 3- (perfluoro-5-methylhexyl) -1,2-epoxypropane, 3- (perfluoro-7-methyloctyl) -1,2-epoxypropane , 3- (perfluoro-9-methyldecyl) -1,2-epoxypropane,
3- (2,2,3,3-tetrafluoropropoxy) -1,2-epoxypropane, 3- (1H, 1H, 5H-octafluoropentyloxy) -1,2-epoxypropane, 3- (1H, 1H, 7H-dodecafluoroheptyloxy) -1,2-epoxypropane, 3- (1H, 1
H, 9H-hexadecafluorononyloxy) -1,2-epoxypropane, etc. are listed.
One kind or a mixture of two or more kinds can be used, and the copolymerization ratio with other compounds constituting the present invention is preferably 50 to 85 parts by weight.

Examples of compounds having an epoxy group and a hydrolyzable silyl group in one molecule include β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltriethoxy. Silane, 3-glycidoxypropyldimethylmethoxysilane, 3-glycidoxypropyldimethylethoxysilane, (3-glycidoxypropyl) trimethoxysilane, 3-glycidoxypropyl) triethoxymethoxysilane and the like, From these, one kind or a mixture of two or more kinds can be used according to the required performance, and the copolymerization ratio with other compounds constituting the present invention is 15 to obtain a cured film having a sufficiently high degree.
-50 parts by weight or more is desirable.

An example of a compound copolymerizable with a compound having an epoxy group and a fluoroalkyl group in one molecule and a compound having an epoxy group and a hydrolyzable silyl group in one molecule, which constitutes the present invention, is ethylene. Oxide, propylene oxide, styrene oxide, 2,3-epoxybutane, 1,2-epoxybutane, isobutene oxide, 1,
2-epoxyhexadecane, chlorostyrene oxide,
Epoxydodecane, allyl glycidyl ether, cyclohexene oxide, 4-vinylcyclohexene oxide, butadiene monooxide, dipentene oxide, 1,2-epoxydodecane, etc. may be mentioned, and one or more of these may be selected depending on the required performance. Can be used as a mixture, and the copolymerization ratio with other compounds constituting the present invention is preferably 0 to 35 parts by weight or more in order to obtain a cured film having a low refractive index.

These epoxy compounds become copolymers by cationic or anionic polymerization. Examples of the cationic polymerization catalyst include protonic acids such as sulfuric acid, hydrochloric acid, perchloric acid and trichloroacetic acid, and Lewis acids such as trifluoroboron, trichloroaluminum, tetrachlorotitanium, tetrabromotin, trichloroantimony and trichloroiron. Examples of anionic polymerization catalysts include organic metal compounds such as alkyl sodium, alkyl lithium, alkyl magnesium, and alkyl aluminum, metal alkoxides such as sodium alkoxide, potassium alkoxide, magnesium alkoxide, aluminum alkoxide, sodium hydroxide, potassium hydroxide, and the like. Examples thereof include strong alkalis, amines such as pyridine and triethylamine. The polymerization catalyst of these epoxy compounds varies depending on the compound to be polymerized, but is 0.01 to
Use 5 parts by weight.

Polymerization of the above-mentioned monomer components for producing a copolymer may be carried out by a method known per se, such as solution polymerization or bulk polymerization. In the case of solution polymerization, the solvent used is It is also possible to use a solvent which is a good solvent for the obtained polymer and does not contain halogen, for example, an ether solvent such as ether, tetrahydrofuran or ethylene glycol dimethyl ether, or a hydrocarbon solvent. Of course, two or more kinds can be appropriately used together and used as a solvent. The solution concentration is 20-100%.

In order to carry out coating using the resin of the present invention, any method used in ordinary glass coating such as coating using a doctor blade, bar coater, applicator, spray coating, spin coating, dip coating, etc. is adopted. It is possible. In the present invention, a catalyst for hydrolysis of the hydrolyzable silyl group in the resin, hydrolysis for promoting the condensation reaction, and a condensation reaction can be used as necessary.

Typical catalysts for the hydrolysis and condensation of the hydrolyzable silyl group are butylamine, dibutylamine, hexylamine, t-butylamine, ethylenediamine, triethylamine, isophoronediamine, imidazole, lithium hydroxide and hydroxide. Basic compounds such as sodium, potassium hydroxide and sodium methylate; tetrapropyl titanate, tin octylate, lead octylate, cobalt octylate, zinc octylate, calcium octylate, lead naphthenate, cobalt naphthenate,
Metal compounds containing dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, dibutyltin malate; formic acid, acetic acid, propionic acid, p-toluenesulfonic acid, trichloroacetic acid, phosphoric acid, monoalkylphosphoric acid, dialkylphosphoric acid, β -Hydroxyethyl (meth) acrylate phosphoric acid esters, monoalkyl phosphites, dialkyl phosphites and other acidic compounds are listed, but especially tin such as dibutyltin diacetate dibutyltin dioctate, dibutyltin dilaurate and dibutyltin dimaleate. Compounds are desirable. The amount of this catalyst used is in the range of 0.1 to 10 parts by weight, preferably 0.2 to 5 parts by weight, based on 100 parts by weight of the resin.

[0012]

In the present invention, the antireflection resin composition is soluble in a solvent containing no fluorine or chlorine and has no crystallinity, and therefore exhibits high transparency and high light transmittance. The antireflection effect is excellent due to the low rate.
Further, since it contains an alkoxysilyl group, it is considered to have excellent adhesion to the substrate by hydrolysis-condensation of the silyl group, self-crosslinking to give a hard coating film, and excellent in moisture resistance, weather resistance and the like. .

[0013]

EXAMPLES Next, examples of the present invention will be described more specifically. In the examples, all parts are parts by weight. All resin synthesis was performed under a nitrogen atmosphere.

(Synthesis Example 1) 3- (1H, 1H, 7H-dodecafluoroheptyloxy) -1,2-epoxypropane 80 parts was placed in a four-necked flask equipped with a cooling tube, a stirrer and a nitrogen introducing tube. 20 parts of (3-glycidoxypropyl) trimethoxysilane was charged into a flask, and 1 part of trifluoroboron diethyl ether complex was added at room temperature. After the heat generation was stopped, the temperature was raised to 60 ° C. and the mixture was stirred for 2 hours to obtain a polymer having a refractive index of 1.3753. (Synthesis example 2) 4 equipped with a cooling pipe, a stirrer, and a nitrogen introducing pipe
In a one-necked flask, 3- (1H, 1H, 7H-dodecafluoroheptyloxy) -1,2-epoxypropane 70 parts, 3-perfluorooctyl-1,2-epoxypropane 10 parts, (3-glycid 20 parts of (xypropyl) trimethoxysilane was charged into a flask, and the same procedure as in Synthesis Example 1 was followed to obtain a polymer having a refractive index of 1.3728.

(Synthesis Example 3) 3- (1H, 1H, 7H-dodecafluoroheptyloxy) -1,2-epoxypropane 60 parts was placed in a four-necked flask equipped with a cooling tube, a stirrer and a nitrogen introducing tube. 20 parts of 3-perfluorooctyl-1,2-epoxypropane and 20 parts of (3-glycidoxypropyl) trimethoxysilane were charged into a flask, and then a polymer having a refractive index of 1.3712 was prepared in the same manner as in Synthesis Example 1. Obtained. A coating solution was prepared by adding 0.1 part of paratoluenesulfonic acid and 490 parts of ethyl acetate to 10 parts of the polymer thus obtained. This coating solution was applied to a glass plate with a 1 mil applicator, and then baked in an oven at 200 ° C for 10 minutes. Various tests were carried out on the antireflection film thus formed. The test items and methods are as follows.

Hardness: Measured at room temperature by a method according to JIS K5400. Peeling test: After cross cutting, cellophane tape peeling was performed, and the percentage of peeling of the coating film was shown. Water resistance: The condition of the coating after rubbing the coating with water gauze 10 times is evaluated on a scale of 1 to 1 (poor) --- 5 (good). Solvent resistance: The coating is gauze with methyl ethyl ketone.
Five-step evaluation of the state of the coating film after rubbing 10 times 1 (poor) --- 5
(Good) Reflectance: The reflectance of the coating film at 600 nm was measured with UV-3100 (manufactured by Shimadzu Corporation). The results are shown in Table 1. Table 1 Various physical properties of antireflection film ────────────────────────────────── Refractive index Hardness Peeling test Water resistance Water resistance Solvent reflectivity ────────────────────────────────── Synthesis Example 1 1.3753 5H 100/100 55 5 2.8 Synthesis Example 2 1.3728 5H 100/100 5 5 2.8 Synthesis Example 3 1.3712 5H 100/100 5 5 2.8 Reference (glass plate) 10.1 ──────────────────────── ───────────

EFFECT OF THE INVENTION The resin for an antireflection film of the present invention, which contains a hydrolyzable silyl group, is extremely easy to form a film having good adhesion to a substrate and high hardness by coating and baking for a short time. Therefore, it is particularly useful for mass-produced optical products such as cathode ray tubes.

Claims (2)

[Claims] 1. A copolymer obtained by cationically or anionically polymerizing a compound having a poxy group and a fluoroalkyl group in one molecule and a compound having an epoxy group and a hydrolyzable silyl group in one molecule. A resin for an antireflection film, which comprises: 2. The resin for an antireflection film according to claim 1, which has a refractive index of 1.4 or less.