JPH03172369A - Coating composition - Google Patents

Abstract

PURPOSE:To obtain the title composition containing an organosilicon compound, etc., and specific tin oxide fine grains, especially useful for plastic lens having high refractive index and capable of providing a coating film having excellent scratch resistance, adhesion and water resistance. CONSTITUTION:The objective composition obtained by blending (A) a compound expressed by the formula (R<1> is 4-14C organic group containing epoxy; R<2> is 1-4C alkyl or 1-4C acyl; R<3> is 1-6C alkyl; (a) and (b) are 0 or 1) or hydrolyzed product thereof with (B) tin oxide fine grains (preferably having 1.82-1.86 refractive index, 1.095-1.115 specific gravity at 25 deg.C, pH 6.5-8.5 and 10 viscosity at 25 deg.C) covered with tungsten oxide fine grains and having 1-100mmu grain size at a ratio of solid content of the ingredient B/used amount of the ingredient A of 1/50-5/1 and further adding, as necessary, curing agent, surfactants, etc., to the blend.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a coating composition, which has excellent scratch resistance, adhesion, and water resistance when applied to and cured, particularly on a high diffraction index plastic lens. The present invention relates to a coating composition that provides a coating film.

[Prior Art] In recent years, plastics have come to be used instead of inorganic glass as eyeglass lens materials. Plus Deck lenses have many advantages over inorganic glasses, such as being lighter and having better impact resistance than conventional glass lenses, and being easier to dye.

However, diethylene glycol-rubisallyl carbonate homopolymer (hereinafter abbreviated as CR-39), which is used as the main material for plastic lenses, has a refractive index of 1.5.
0, which is lower than that of inorganic glass, and the edge thickness is particularly large in minus lenses, so there is a demand for thinner plastic lenses.

Various proposals have been made in response to the demand for thinner plastic lenses. For example, JP-A-57212401 proposes a high refractive index plastic lens made of a copolymer of diethylene glycol, sallyl carbonate, pendyl methacrylate, and diallyl isophthalate. Further, JP-A-60-199016 proposes a high refractive index plastic lens made of a copolymer of polyisocyanate and polyol or polythiol. However, these B refractive index lenses also have r! resistance like other plastic lenses. Poor Ie properties. To improve the scratch resistance of plastic lenses,
For example, Japanese Patent Application Laid-Open No. 10640/1983 discloses that a coating liquid containing an organosilicon compound and colloidal silica is applied to a plastic lens and cured to form a cured film. However, the above-mentioned Japanese Patent Application Publication No. 63-1064
When the coating liquid disclosed in Publication No. 0 is applied to the above-mentioned high refractive index plastic lens and cured to form a cured film, interference fringes occur because the refractive index of the cured film is lower than that of the plastic lens. is recognized and is not practically preferable. As a cured film that does not generate interference fringes, for example, Japanese Patent Publication No. W461-54331 proposes a cured film using an organosilicon compound and antimony pentoxide fine particles.

[Problems to be Solved by the Invention] A cured film obtained from a coating composition containing an organosilicon compound and fine particles of andymon pentoxide proposed in Japanese Patent Publication No. 61-54331 has good scratch resistance and water resistance. Not enough. For this reason, when the coating liquid is applied to a plastic lens and cured to form a cured film and used as an eyeglass lens, scratches are likely to occur, and the physical properties of the cured film tend to deteriorate over time. This causes the problem that the scratch resistance of the membrane becomes even weaker. The present invention has been made to solve these problems, and its purpose is to provide a lens that has excellent scratch resistance, good adhesion to plastic lenses, antireflection films, etc., and that is suitable for use as a lens for eyeglasses. However, it is an object of the present invention to provide a coating composition that can form a cured film on a high refractive index plastic lens 1- in which the physical properties of the cured film do not easily deteriorate over time.

[Means for Solving the Problems] As a result of intensive research to achieve the above-mentioned object, the inventor of the present invention found that (A) - Maximum % formula % () (where R1 contains an epoxy group and has 4 carbon atoms) ~14 i groups, R2 is an alkyl group having 1 to 4 carbon atoms or 1 carbon number
~4 alkyl group or a C1-6 alkyl group, a
and b represents an integer of O or 1) or a hydrolyzate thereof.

([3) Particle size 1~ coated with tungsten oxide fine particles
The inventors have discovered that a coating composition characterized by containing 100 millimicron tin oxide fine particles achieves the above object, leading to the present invention.

The present invention will be explained in detail below.

Examples of organosilicon compounds represented by the general formula (%) or hydrolysates thereof used as component (A) in the present invention include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, ethoxysilane,
γ-glycidoxyprobyldimethoxyethoxysilane,
γ-glycidoxyprobyltriacetoxysilane, (3
, 4-epoxycyclohexyl)■ Examples include, but are not limited to, tiltrimethoxysilane, T-glycidoxyprobyldimethylmonomethoxysilane, methyltrimethoxysilane, and their hydrolysates. .

The tin oxide fine particles with a particle size of 1 to 100 millimicrons coated with tungsten oxide fine particles used as component (B) in the present invention are in the form of a colloidal solution in which the fine particles are dispersed in water, an organic solvent, or a mixed solvent thereof. It is used to increase the refractive index and scratch resistance of the cured film, as well as to improve its water resistance. Examples of organic solvents used to disperse tin oxide particles coated with tungsten oxide particles include alcohols such as methanol and ethanol.

The particle size of the tin oxide fine particles is limited to 1 to 100 millimicrons, particularly preferably 5 to 20 millimicrons. The reason for this is that if the particle size is less than 1 millimicron, the particles will lack stability and the cured film will be poor in durability, and if the particle size exceeds 100 millimicrons, the cured film will lack transparency, which is undesirable. be.

Incidentally, the term "tin oxide fine particles coated with tungsten oxide fine particles" refers to a structure in which tungsten oxide fine particles and tin oxide fine particles are formed by chemical and physical bonding, and the tungsten oxide fine particles surround the tin oxide fine particles. The refractive index of the tin oxide fine particles coated with the tungsten oxide fine particles is 1.82 to 1.86, and the specific gravity is 1.82 to 1.86 at 25°C.
Particularly preferably used are those having a pH of 6.5 to 8° at room temperature and a viscosity of 10 or less at 25°C. Furthermore, negatively charged tin oxide fine particles coated with tungsten oxide fine particles are particularly preferably used in order to improve compatibility with silane coupling agents, organic solvents, surfactants, silica sol, and the like.

The amount of tin oxide fine particles coated with tungsten oxide fine particles is such that the ratio between the solid content m of tin oxide coated with tungsten oxide fine particles/the silicon compound or its hydrolyzate used is 1150 to 5/ It is preferable that it be 1. The reason is that when the ratio is 1150, the refractive index of the cured film is
The range of application to base materials is significantly limited, and the 5/5
This is because if it exceeds 1, cracks are more likely to occur between the cured film and the substrate, further increasing the possibility of deterioration of transparency.

The coating composition of the present invention can also use a curing agent to accelerate the reaction and cure at low temperatures. Examples of the curing agent include amines such as allylamine and ethylamine, various types of hydrogen and bases including Lewis acids and bases, such as organic carboxylic acids, chromic acid, hypochlorous acid,
Examples include metal salts such as boric acid, bromic acid, selenite, thiosulfuric acid, orthosilicic acid, thiocyanic acid, nitrous acid, aluminic acid, and carbonic acid, as well as alkoxides of aluminum, zirconium, and titanium, and complex compounds thereof.

In addition, the coating composition of the present invention is coated with oxidized metals such as aluminum, titanium, antimony, zirconium, silicon, and cerium in order to match the refractive index of lenses serving as various substrates and to further improve scratch resistance. It is possible to add fine particulate inorganic substances consisting of substances.

Various surfactants may be added to the coating composition of the present invention for the purpose of improving flowability during coating and improving smoothness of the cured film.

Further, ultraviolet absorbers, antioxidants, etc. can also be used as long as they do not affect the physical properties of the cured film. As the coating means, commonly used methods such as dipping, spinning, and spraying can be used, but dipping and spinning are particularly preferred from the viewpoint of surface precision.

The objects to be coated with the coating composition of the present invention include methyl methacrylate homopolymers, copolymers containing methyl methacrylate and one or more other monomers as monomer components, diethylene glycol bisallyl carbonate homopolymers, diethylene glycol Examples include copolymers containing bisallyl carbonate and one or more other monomers as monomer components, plastic lenses such as polycarbonate, polystyrene, polyvinyl chloride, polyethylene terephthalate, and polyurethane, and inorganic glass lenses.

The coating composition of the present invention is cured by hot air drying or irradiation with active energy rays.
It is best to carry out in hot air at 00°C, particularly preferably at 90°C.
~150°C is desirable. Active energy rays include far infrared rays, which can suppress damage caused by heat.

Furthermore, before applying the coach ink composition of the present invention to the base material, chemical treatment with acid, alkali, or various organic solvents,
The adhesion between the base material and the coating film can be improved by physical treatment using plasma, ultraviolet rays, etc., cleaning treatment using various detergents, and further, primer treatment using various resins.

Furthermore, as a high refractive index film, it can of course be used as an antireflection film, and further, by adding functional components such as antifogging, photochromic, and antifouling, it can also be used as a multifunctional film.

[Examples] Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples. In addition,
Physical properties of the plastic lenses having cured films obtained in Examples and Comparative Examples were measured using the measurement methods shown below.

(1) Scratch Resistance Test The lens surface was rubbed with steel wool #0OOO, and the scratch resistance was visually judged.

The judgment criteria were as follows.

A... There will be almost no scratches even if you rub it hard B... You will get a lot of scratches if you rub it hard C... You will get scratches equivalent to the lens board (2) Presence of interference fringes Visually check under fluorescent light did. The criteria for judgment are as follows.

A... Interference fringes are almost invisible B... Slightly visible C... Quite visible (3) Adhesion test Cross-cut 100 stitches at 1 sliJ intervals, and apply adhesive tape (
A adhesive (trade name: "Cellotape", manufactured by Nichiban ■) was strongly applied and then rapidly peeled off to examine whether or not the cured film had peeled off.

(4) Scratch Resistance Test A 16 g steel ball was dropped from a height of 127 cJI onto the center of a lens with a center thickness of 2 All to check for damage.

(5) Water Resistance Test The above-mentioned scratch resistance test and adhesion test were conducted by immersing the product in warm water at 50° C. for 5 hours.

(6) Transparency test The lenses were visually inspected to see if they were cloudy under fluorescent light in a dark room. The judgment criteria are as follows.

Δ...Cloudy is hardly visible.

B...It's a little visible.

C...It's quite visible.

[Example 1] (Preparation of coating liquid) 70 parts by weight of γ-glycidoxypropyltrimethoxysilane, component (A), was added to a glass container equipped with a magnetic stirrer, and while stirring, 16 parts by weight of 0.1N hydrochloric acid was added dropwise.

After the addition was completed, the mixture was stirred for 24 hours to obtain a hydrolyzate.

Next, 105 parts by weight of water-dispersed tin oxide fine particles (solid content 20%, average particle size 15 mm) coated on tungsten oxide fine particles as component (B), 80 parts by weight of isopropyl alcohol as a solvent, 11 parts by weight of ethyl ceresol, 8
0 parts by weight, and 1 part of silicone surfactant as a lubricant.
The bug stone part and 4 parts by weight of aluminum acetylacetonate as a hardening agent were added, thoroughly stirred, and then filtered to obtain a coating liquid.

(Formation of a cured film) A plastic lens (refractive index n, 1°56) made of diethylene glycol, sallyl carbonate, benzyl methacrylate-1, and diallyl isophthalate was immersed for 5 minutes in a 10% NaOH aqueous solution at 45°C. After washing, coating was performed using the dip method (pulling speed 14 cm/min) using the coating solution prepared in the above manner, and heating at 130°C for 2 hours to form a cured film, and various evaluations were conducted. I did it.

As shown in Table 1, the plastic lens with the cured film obtained by the above method was confirmed to have good scratch resistance and adhesion, almost no visible interference fringes, and excellent water resistance. It was done.

Example 2 The same (Δ
) The same procedure as in Example 1 was conducted except that the component β-(3,4 epoxycyclohexyl)ethycytrimethoxine 0 repeats was used. As shown in Table 1, the evaluation results showed that it had excellent physical properties similar to Example 1.

[Example 3] Instead of 70 parts by weight of γ-glycidoxypropyltrimethoxysilane as the component (Δ) used in Example 1, 1 part of meblutrimethoxysilane 7Offiff and 4 parts of aluminum acetylacetonate were used as a curing agent. Everything was carried out in the same manner as in Example 1 except that 4 parts M of sodium acetate was used instead of the part. As shown in Table 1, the evaluation results showed that it had excellent physical properties similar to Example 1.

[Comparative Example 1] Instead of 105 parts by weight of tin oxide fine particles coated with tungsten oxide fine particles as component (B) used in Example 1, 78 parts by weight of methanol-dispersed antimony sol (solid content 30%, average particle diameter 15 mm) was used. Example 1 except that
I did the same thing.

As shown in Table 1, the rP value results showed poor scratch resistance and water resistance.

[Comparative Example 2] All procedures were carried out except that water-dispersed colloidal silica (solid content 20%, average particle size 15 mm) was used instead of the tungsten oxide fine particle-coated tin oxide fine particles used in component (B) in Example 1. The same procedure as in Example 1 was carried out. As a result, interference fringes were generated as shown in Table 1, and the appearance was unfavorable.

[Comparative Example 3] Water-dispersed tin oxide fine particles (solid content 20%, average The same procedure as in Example 1 was carried out except that 105 particles (particle size: 10 mm/micron) were used. As shown in Table 1, the film was too cloudy to be used practically.

[Effects of the present invention] As described above, according to the present invention, it has excellent resistance to 122 (1a) and adhesion, and even when formed on a high refractive index plastic lens, no interference fringes are observed. It has now become possible to provide a coating composition whose cured film properties do not easily deteriorate even when exposed to hot water.

Claims (1)

[Claims] (A) General formula (R^1)_a(R^3)_bSi(OR^2)_4_
-_(_a_+_b) (where R^1 is an organic group having 4 to 14 carbon atoms, including an epoxy group, R^2 is an alkyl group having 1 to 4 carbon atoms or an acyl group having 1 to 4 carbon atoms, R^ 3 is
an organosilicon compound or its hydrolyzate represented by an alkyl group having 1 to 6 carbon atoms, a and b each representing an integer of 0 or 1; and (B) a particle size of 1 to 1 coated with tungsten oxide fine particles.
1. A coating composition comprising: 00 millimicron tin oxide fine particles.