JPH02242864A - Uv resistant,abrasion resistant covering - Google Patents

Abstract

PURPOSE: To obtain a transparent abrasion-resistant coating film which protects a plastic material such as a polycarbonate from UV by mixing a specified partially hydrolyzed alkoxide and a specified hydroxy organic compound.

CONSTITUTION: This composition comprises a partially hydrolyzed alkoxide represented by the formula (wherein R is an organic radical; M is Si, Al, Ti, Zr or Ce; R' is a low-molecular-weight alkyl radical; (z) is the valence of M; and (x) is below (z) and may be 0) and an ultraviolet-absorbing hydrophilic- moiety-containing organic hydroxy compound.

COPYRIGHT: (C)1990,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Field of the Invention This invention relates generally to protective coatings for plastics, such as polycarbonates, and more particularly to ultraviolet ray protection coatings.
It relates to a coating that protects the underlying substrate from damage caused by condensation.

(2) U.S. Patent No. 4.27 to Baney et al.
5.118 is a coating comprising an acidic dispersion of colloidal titanium oxide, colloidal silica, and hydroxylated silsesquioxane in an alcohol-water medium that produces a hard, abrasion-resistant coating when cured on plastic surfaces such as polycarbonate. A composition is disclosed.

4.299 for U.S. Patent to Frye.
746 is an improved silicone resin prepared by hydrolyzing an alkyltrialkoxysilane in an aqueous colloidal silica dispersion and adding a small amount of a UV absorbing compound such as 2,4-dihydroxybenzophenone to the hydrolysis product. Abrasion resistant coating compositions are disclosed.

4°39 for U.S. patent to White (formerly TE) et al.
0.373 and 4.44.2,168 are R(S +
Partial condensate of (OH)3) (where R is an organic radical)
An effective wear-resistant colloidal dispersion containing colloidal antimony oxide and colloidal silica in a water-alcoholic solution in a weight ratio of less than about 30 Nia or equivalent.
A hardened, clear, abrasion resistant coating composition is disclosed.

U.S. Pat.
A method of improving the weatherability of a polycarbonate substrate by then passing a curable silicone hard coat composition over the treated surface is disclosed.

U.S. Patent No. 4,405,679 to Fuji Sairiki et al.
A molded polycarbonate substrate coated with an improved abrasion resistant polycarbonate-type resin, including an undercoat applied and cured over the substrate, and an overcoat applied over the undercoat. A molded article is disclosed.

The overcoat includes an epoxy-containing silicon compound that is at least one member of the deglacial group of organosilicon compounds, colloidal silica, organotitanic acid, and a curing catalyst.

4.477. to Dotn et al.
No. 499 discloses a UV resistant silicone resin coating with improved ripeness and reduced aging requirements achieved by adding a Lewis acid compound to the coating composition.

U.S. Pat. No. 4,500,669 and 4,571,365 to Ashlock et al. A clear, abrasion resistant coating composition is disclosed comprising a colloidal dispersion of a condensate dispersed in an aqueous-alcoholic solution.

4,552 for U.S. Patent to Moore (HOOre)
．． No. 936 discloses protective coating compositions containing polycaprolactone polyols and aminoplast derivatives that are applied to thermoplastic substrates to create thermoformable articles that are abrasion resistant, solvent resistant, and weather resistant.

No. 4,615,947 to Goosens discloses a brimer layer comprising a thermoplastic or thermosetting acrylic homogeneous mixture with an organopolysiloxane to increase abrasion adhesion and a solvent-resistant organopolysiloxane to a thermoplastic substrate. Hard court is listed.

U.S. Pat. No. 4,68 to Curry et al.
No. 3.169 discloses a methyl methacrylate UV protective coating for polycarbonate films with improved resistance to microcracks.

European patent application no. An intermediate comprising a dispersion of a colloidal metal oxide in a water-alcoholic solution of a partial condensate is disclosed. Here metal oxides are zro, sno, zrsio
4°B203 or La2O3.

Optical quality abrasion resistant coated plastic materials typically require a coating that protects the substrate from ultraviolet (UV) damage. Hydrolytic deterioration is 1Ili to UV! Protection from UV radiation is particularly important for polycarbonates, as the UV radiation is clearly accelerated by The most typical organic U■ absorbent is
Due to low solubility it is not possible to add sufficient strength to water/alcohol based sol-gel type abrasion coating compositions without adversely affecting the hardness and adhesion of the coating. Since it is not possible to provide sufficient protection to the abrasion resistant coating, the conventional U-stabilizers do not provide sufficient protection to the abrasion resistant coating. Additionally, typical U.sub.2 absorbers typically lose activity over time after long-term exposure and may also gradually leach out of the composition.

(3) SUMMARY OF THE INVENTION The present invention provides protection from UV damage to underlying plastic substrates, such as polycarbonate, by forming a transparent coating comprising a UV-absorbing organic compound containing a hydrophilic moiety with terminal hydroxyl groups. The compounds can react with the silanol groups in the partially hydrolyzed sol of silicon and/or other metal alkoxides, and they impart wear resistance to the plastic substrate surface through hydrolysis and polycondensation. Form a film that gives. The hydrophilically improved hydroxybenzotriazole and hydroxybenzophenone derivatives of this invention are compatible with alcoholic/aqueous sol-gel compositions and processes that impair the abrasion resistance of inorganic oxide coatings! Provides UV protection without The invention also provides protection from ultraviolet radiation damage to underlying plastic substrates such as polycarbonate, and the method describes the use of hydroxybenzophenone and hydroxybenzotriazole in a polymeric mixture of (meth)acrylic copolymers. A coating of a composition that includes a UV-absorbing organic compound that is a colorless, highly efficient UV absorber and an aggressive solvent that enhances the adhesion of the coating to the substrate.

(4) DESCRIPTION OF THE PREFERRED EMBODIMENTS Coatings that protect plastic substrates, such as polycarbonates, from damage caused by ultraviolet radiation are formed from sols containing network-forming metal alkoxides, such as alkoxysilanes and other metal alkoxides. Alkoxysilanes are organoalkoxysilanes such as alkylalkoxysilanes or other organofunctional alkoxysilanes. The alkoxides may contain alkyl or aryl groups and may be in 2ffi or higher fused forms as far as the remainder of the hydrolysable alkoxide groups are concerned. A UV-absorbing organic compound containing a hydroxy group capable of reacting with a silanol group is added to the partially hydrolyzed sol. Hydrolysis and condensation occur in situ. Alternatively, the alkoxide is partially or completely hydrolyzed and then, after some condensation, combined with an organic U2 absorber containing hydroxyl groups, preferably hydroxybenzotriazole.

Conventional UV absorbers such as benzophenones and benzotriazoles and their alkyl derivatives have low solubility in alcohol-water based plain sol-gel type abrasion coatings. And also because there is no covalent bond between the conventional UV absorber and the inorganic coating matrix, the UV absorber will leach out during class 11 use.

According to this invention, hydroxybenzotriazole and hydroxybenzophenone UV absorbers are modified with the extension of hydrophilic chains with terminal hydroxy groups for integrated reaction with inorganic sol to form part of the polymer oxide network upon curing. Become. The presence of ethoxy and/or b-O-boxy hydrophilic moieties provides a liquid organic UV absorber while improving miscibility with inorganic sols. Hydroxybenzotriazoles substituted with polyethylene glycols of the following formula are preferred U■ absorbers according to this invention.

Here n is 1 to 10. A preferred composition is Ttnuvin 1130 from Cipa Geigy.
obtained as.

The resulting composition can be used as a coating composition, both as a primer or as a protective coating for a substrate or a coated substrate. Alternatively, the composition can be added to other coating compositions, such as abrasion resistant coating compositions, to increase resistance to ultraviolet light. In either case, the coating composition can be applied by any of the conventional techniques such as spraying, dipping, or drop coating. The composition dries and cures to form a uniform durable coating that adheres well to plastic substrates such as polycarbonate. The coating protects the substrate from ultraviolet radiation by providing strong and broad absorption in the 240 to 380 nanometer range.

In a preferred practical IM embodiment of this invention, the alkoxide is partially hydrolyzed prior to adding the ultraviolet absorbing organic compound containing a hydrophilic extension with a hydroxyl group end capable of reacting with a silanol group. Preferably, the alkoxide is an alkoxysilane of the general formula RXSi(OR') selected from the group consisting of x 4-x where R is an organic radical and R' is a small molecular machine alkyl radical, and X is less than 4 and may be zero. good. The organic radical R is preferably alkyl, vinyl, methoxyethyl, phenyl, γ-glycidoxypropyl or γ-methacryloxypropyl. Alkoxides are hydrolyzed by the following general reaction.

RxS r (OR') 4-x + , H20→R
xS i (OR') 4-X-, (OH), +
, R' OH The condensation of the hydrolyzed alkoxide proceeds by the following general reaction.

2RS; (OR') 4-%-17゛X (OH), → RxS i (OR') 4-x-y-1(OH)
.

or 2RXS i (OR') 4-x-y (OH)
,→RxS i (OR') 4-x-y (OH)
Further hydrolysis and condensation of y-1 follows this with condensation with hydrophilic hydroxybenzotriazole.

The pH and/or the degree of alkoxide condensation can be adjusted if necessary. thereby preventing clouding or precipitation upon mixing with the organic UV absorber, preferably ethoxylated or propoxylated hydroxybenzotriazole, and partially hydrolyzing the terminal hydroxy groups of the hydrophilic elongated steel of the organic UV absorber. Facilitates condensation reaction with metal alkoxides. The sol preferably contains about 0.5 to 5.0 percent hydrophilic hydroxybenzotriazole in solid form.

Titanium and/or zirconium alkoxides are also included in the compositions of this invention, as is colloidal silica for wear resistance. The UV protection provided by the hydrophilic hydroxybenzotriazole-containing coatings of this invention is determined by measuring the Uv absorption spectra of the coatings applied on quartz substrates.

To coat polycarbonate substrates with the abrasion resistant sol-gel compositions of this invention, an acrylic primer solution is preferably prepared as shown below.

Thermoplastic acrylic primers are prepared by combining polymethyl methacrylate-1- and polyethyl methacrylate in an aggressive solvent. Organic UV absorbers are added to provide U■ protection. Addition of flow regulators is preferred.

Polymethyl methacrylate and polyethyl methacrylate may include mixtures of homopolymers or may be copolymerized. Preferably, the composition contains 60 to 90 percent polymethyl methacrylate and 10 to 40 percent polyethyl methacrylate. The average molecular weight of the polymer was determined by gel permeation chromatography to be 80.
A range of 000 to 350.000 is preferred.

A clean polycarbonate substrate is applied with the brimer solution of this invention, preferably by dipping or pouring, and then air dried for about 15 minutes until tack-free. The plastic substrate provided with the primer is dried in an oven at 60 to 100° C. for 30 minutes.

Anti-U primers, which protect substrates such as polycarbonate from damage caused by ultraviolet light, are formed with environmentally stable acrylates as the main matrix. Such hemolecular acrylates not only provide significant cross-linking adhesion between the inorganic-based topcoat and the polycarbonate, but also provide significant resistance to hot, humid environments and UV radiation. According to this invention, 65℃ and 105℃
Acrylic matrices are preferred that give a glass transition temperature between 0.1 and 1.0, the type of (meth)acrylate unit, the molecular weight of the polymer, and the method of incorporation, such as mixing or copolymerization, are chosen to provide optimal properties.

Equally important in this invention is the selection of the specific UV absorber, which affects both the efficiency of UV protection and the ftL sensitivity to humidity, and this is due to the efficiency of the UV absorber and molecular Depends on suitability. The poor molecular compatibility and compatibility between the brimer matrix and the UV absorber may result in relatively short retention of the UV absorber during topcoat application or its apparent optical clouding. humidity resistance becomes low or UV absorbers leach out after short-term use.

Preferred acrylic matrices according to the invention include poly(methyl methacrylate) of 60 to 9011111 and 4
It is made by mixing 0 to 10 parts of poly(ethyl methacrylate), preferably 80 to 90 parts of poly(ethyl methacrylate) and 10 to 20 parts of poly(ethyl methacrylate) in a weight a ratio. Alternatively, copolymers corresponding to acrylates and their derivatives can also be used satisfactorily as matrices for UV absorbers in the present invention's primers.

Preferably, UV absorbers of the benzotriazole type can be chosen for their better compatibility with the main acrylic matrix compared to UV absorbers of the benzophenone type. Preferred compositions of this invention can have a variety of substituents on the hydroxybenzotrier ring, such as those shown below.

Here, R and R2 are hydrogen, alkyl, aryl, etc. Preferred uv@ablifiers of this invention include benzotriazoles of the above type, where R1 and R2 are 1,1-dimethylbenzylphenyl (Tinuvin from Ciba Geigy)
Tinuvin) 900), R is t-butyl and R
2 is polyethylene glycol propionate ester (
Tinuvin 1130 from Ciba Geigy), or R1 is hydrogen and R2 is octylphenyl (Cyasorb 5411 from American Cyanamid)
).

The invention will be better understood from the specific examples described below.

(5) Example 1 An abrasion resistant and UV resistant silane/zirconia coating was made as follows. The organic alkoxysilane composition is 25
grams of methyltriethoxysilane and 50 grams of γ-
Prepared by mixing with propylacryloxytormethoxysilane. 1.8 grams of ethoxylated hydroxybenzotriazole (Tinuvin 1130 from Ciba Geigy) was added to the organoalkoxysilane. The composition was stirred for 10 minutes and then 30 grams of 2-buOpanol, 8 grams of deionized water, and 5 drops of hydrochloric acid were added to hydrolyze the organoalkoxysilane. The hydrolyzed organoalkoxysilane composition was transparent. Thirty grams of zirconium n-propoxide was added to the hydrolyzed organoalkodisilane. After stirring for 20 minutes, add 20 grams of deionized water and 10 grams of diacetone alcohol simultaneously containing 6 grams of 10 percent ammonium hydroxide and 1.2 grams of additional Tinuvin 1130 to complete the hydrolysis. Ta. The mixture was stirred at room temperature for 2 hours.

Finally, 0.5 grams of azoisobutylnitrile and 5 grams of diacetone alcohol were added.

For comparison, when a hydroxybenzophenone UV absorber was added to such a sol-gel abrasion resistant coating composition, a color change occurred followed by precipitation.

Example 2 Organic UV absorbers with improved miscibility with alcohol-water based inorganic sols are prepared by incorporating water-miscible ethoxylated or propoxylated chenos with terminal and droxy groups. We were able to. A hydrophilic substituted hydroxybenzophenone is e.g.
1.4 grams of 2,4-dihydroxybenzophenone (
11% by dissolving 0.10 mol) and a trace amount of potassium hydroxide in 100 grams of dioxane in a reaction vessel.
It was done. A solution of 23.2 grams of propylene oxide in 35 grams of dioxane is added to a solution of 35 grams of dioxane at 20°C.
It was added slowly for 0 minutes and then raised to 35°C for another 30 minutes. The reaction was quenched by adding about 5 grams of water to the dioxane. The reactants were collected by precipitating the reactants from the solvent by adding a large amount of peracid water. The miscibility of the substituted products depends on the length of propoxylation, which is also determined by the molar ratio of propylene oxide to benzophenone.

11 Fengyu Ying ff4 The reaction mixture consisted of 100 grams of methyltriethoxysilane (Union Carbide's A-162), 10 grams of dimethyljethoxysilane, 60 grams of silica sol (Shubon's Ludox LS), and 3.6 I was prepared containing gram of acetic acid. The mixture was allowed to react at room temperature.

After approximately one day of reaction, the mixture was diluted with 80 grams of isobutanol and centrifuged. The mixture was divided into three parts, each containing β-[3(2d-penzotriazole-
0,1.5 based on the gel weight of 2-yl-)4-hydroxy-5-t-butylphenyl-]propionic acid.
% and 2% as well as 300 molecular weight polyethylene glycol methyl ester. The reaction was continued for 3 days at room temperature.

The polycarbonate substrate coated with the primer was immersed in the above solution for about 3 minutes and then dried for 15 minutes.
Cure for 1 hour. UV resistance was measured by UV film absorption intensity through the quartz substrate. The adhesive properties of the coating were determined by ASTM D-3359-87 using a Gardner 1l-too scriber.
th 5 criber) was used for the cross scribe in the X direction and then the tape was pulled over the 100 scare three times. Adhesion is said to be excellent when no scares fail.

ASTM F735-81 coated Bayer
er) was used to measure abrasion resistance. A 4" x 4" coated polycarbonate was subjected to 300 2 minute abrasion tests in a vibrating silica sandbox. Changes in the percentage of haze measured by a haze meter (Pacific Scientific's Hazegard system) were reported. Typically uncoated polycarbonate shows a 55-60% increase in haze in this test.

The UV resistance of the coating itself, as well as its ability to protect the underlying substrate from UV damage, is why the coated polycarbonate was tested on fluorescent tubes made by Q Panels Inc. according to the test method described in ASTM G53-77. 831
acceleration Q-IJVf-? It was evaluated by putting it in the sample. The chamber is 70
50 °C for 4 h followed by an 8 h illumination cycle.
It was programmed with a cycle of synthesis at 100% humidity at °C. The appearance of the coating was inspected and the fading resistance was determined according to the yellow index clause (ASTME 308-85, 1) using a JV/V[S spectrophotometer
931 CIE, Illuminant C). Uncoated polycarbonate usually reaches a value of 10 immediately after 100 hours of exposure. The following characteristics were observed.

A reaction mixture containing 80 grams of methyltrimethoxysilane and 8 grams of dimethyljethoxysilane was prepared W4 by dissolving 1.5 grams of polyvinylpyrrolidone in 55 grams of methanol and 55 grams of deionized water. The prepared solution was added. After adding 4 grams of acetic acid, the mixture was stirred at room temperature for 2 hours. Then add 2 grams of Tinuvin 113 to the mixture.
50 grams of diacetone alcohol and 25 grams of isobutanol were added along with 0.0 grams followed by 0.2 grams of potassium acetate. Stirring at room temperature was continued for 3 days.

The cleaned polycarbonate was primed and soaked in the coating composition solution for 3 minutes, air dried for 15 minutes, and then cured at 120°C for 1 hour. An optically clear UV-resistant and abrasion-resistant coating was obtained.

Example 6 1.5 grams of polyvinylpyrrolidone is dissolved in 55 grams of methanol and 55 grams of deionized water until the solution is 1 liter.
111 and then 4 grams of acetic acid were added. To the solution were added 80 grams of methyltrimethoxysilane, 8 grams of dimethyljethoxysilane, and 3 grams of the hydroxybenzophenone proboxylate derivative of Example 2. The reaction mixture was stirred at room temperature for 2 hours, then 50 grams of 2-propatol, 25 grams of diacetone alcohol, and 0.2 grams of potassium acetate were added. The reaction was continued for 3 days at room temperature.

A clean polycarbonate substrate was primed and flow coated with the above coating composition and air dried for 12 minutes.
Cured for 1 hour at 0°C. An optically transparent abrasion-resistant coating was obtained.

Example 7 A thermoplastic acrylic brider was prepared by dissolving 12 grams of polymethyl methacrylate and 3 grams of polyethylene methacrylate in 230 grams of BuO pyrene glycol methyl ether (Dowanol PM from Dow Chemicuff 9) and 20 grams of toluene. . Two grams of Sheasolve 5411 U■ absorbent was added to provide U■ protection.

A flow control agent was added (0.01% by weight of B from BYK Chemicals in siloxane-containing polyether).
YK-300).

Cleaned polycarbonate substrates were soaked or flow coated in the above-mentioned brimer solution for 2 minutes and then dried for about 15 minutes until tack-free. The brimered plastic was dried in an oven at 60 to 100° C. for 30 minutes.

A wear-resistant sol containing 100 grams of methyltriethoxysilane (Union Carbide's Δ-162), 10 grams of dimethyljethoxysilane, 60 grams of silica sol (Shubon's Radox Shi S), and 3.6 grams of acetic acid. - A gel coating was prepared. The mixture was reacted for one day at room temperature, diluted with 80 grams of isobutanol, and then centrifuged. The mixture was divided into two parts, each with β-<3-(2H-benzotriazol-2-yl-)4-hydroxy-5-
t-Butylphenyl-)propionic acid O and 1.5% each were added along with the methyl ester of polyethylene glycol of molecule 1300. The reaction was continued for 3 days at room temperature. Brimered polycarbonate was soaked in the above solution for 3 minutes at 15°C, air dried for 15 minutes, and then cured at 120°C for 1 hour.

U■ resistance was measured by the intensity of U■ absorption through the quartz substrate. The adhesion properties of the coating are as per ASTM D-3359-
87, Gardner's 11-tooth scriber (Ga
rdner 1l-tooth 5criber)
It was measured by using a directional cross scribe and then pulling the tape over a 100 square three times. Adhesion is said to be excellent when no scares fail.

The U resistance of the coating itself as well as its ability to protect the underlying substrate from damage caused by U pipe (831
3 nanometers) in an accelerated Q-UV chamber. The chamber was programmed with an 8 hour illumination cycle at 70°C followed by a 4 hour synthesis cycle at 50°C and 100% humidity. The appearance of the coating was inspected and the fading resistance was determined using a tJV/VIS Svectorov A tometer with Yellow Index 11 (ASTM E308-85).
．． Reported in 1931 CIE, Illuminant C). Uncoated polycarbonate usually reaches a value of 10 immediately after 100 hours of exposure.

The UV resistance of the brimer alone, the abrasion resistant coating with the brimer, and the abrasion resistant coating with the brimer and additional U■ absorber are compared in the table below.

Example 8 A brimer solution of 90 parts polymethyl methacrylate and 10 parts polyethyl methacrylate combines 24.3 grams polymethyl methacrylate and 2.7 grams polyethyl methacrylate with 410 grams Dowanol PM and 133 grams diacetone. Made by dissolving in a warm mixture of alcohol. To the above was added a solution containing 6.7 grams of Dinuvin 900 UV absorber in 32 grams of toluene. 0.05 grams of BYK-300, a siloxane-containing polyether, was added as a flow control agent to obtain an optically smooth surface.

The abrasion resistant coating mixture was prepared by combining 33 grams of deionized water and 3.
Mix 1.8 grams of polyvinylpyrrolidone (PVPK90 from GAF) in 3 grams of methanol with a mixture of 48 grams of methyltrimethoxysilane, 4.8 grams of dimethyljethoxysilane and 2.4 grams of acetic acid. It was prepared by After 2 hours at room temperature, the reaction mixture was mixed with 30 grams of 2-propatool and 1
Diluted with 5 grams of diacetone alcohol.

Then 0.2 grams of sodium acetate was added and the reaction continued for two days. After adding 0.1 grams of BYK-300 flow modifier, the mixture was mixed with 1.8 grams of BioRad (B
10Rad) Cation exchange resin (A6.50W-X8)
The pH was adjusted by ion exchange using

A clean polycarbonate substrate was flow coated with the brimer solution. After air drying for about 15 minutes, apply another 10 minutes of primer.
It was dried for 30 minutes at 0°C. an abrasion resistant coating mixture is flow coated onto the brimered polycarbonate;
It was air dried for 15 minutes and then cured at 120°C for 20 minutes. An optically transparent coating was obtained.

ASTM F735-81 was used to measure the Beyer abrasion resistance of the coatings. A 4" x 4" coated polycarbonate was subjected to an abrasion test of 300 cycles for 2 minutes in a vibrating silica sandbox. , the change in the percentage of haze measured by @Remeter (Pacific Scientific's Bayesguard System) was reported. Typically uncoated polycarbonate scores 55-60 in this test.
% increase in haze.

Abrasion resistance, UV resistance and moisture resistance properties are shown in the Example 2 column of the table below.

Table 1 Example 9 The polymethyl methacrylate/polyethyl methacrylate mixture of Example 2 was replaced with 27 grams of a 60/40 ratio copolymer of methyl methacrylate and ethyl methacrylate (from Polyscience). The UV and moisture resistance properties are shown in the Example 3 column of Table 1 along with the properties of Example 8 (Example 2, III).

Example 10 Brimer is a copolymer of methyl methacrylate and ethyl methacrylate (Polyscience) prepared by dissolving 5.0 grams of 1 m Manufactured. A UV absorber solution containing 0.325 grams of Tinuvin 900 and 0.68 grams of Tinuvin 1130 in 5 grams of toluene was added. A flow modifier (0.01% BYK-300) was added to adjust the flow properties of the coating. This brimer forms an optically transparent layer of approximately 2 μm on top of the polycarbonate. The results are shown in the Example 4 column of Table 2.

Example 11 A brimer solution containing 3.45 grams of methyl methacrylate homopolymer and 0.44 grams of ethyl methacrylate homopolymer was prepared. The mixture is 5
Solubilized in 4.2 grams of propylene glycol methyl ether and 17.6 grams of diacetra alcohol. Uv @ collector solvent solution, 0.0.
It consisted of 75 grams of Tinuvin 1130 and 0.41 grams of Tinuvin 900. The results are shown in the Example 5 column of Table 2.

Example 1a For comparison, a brimer solution using a homopolymer of polyethyl methacrylate was prepared by adding 4.29 grams of polyethyl methacrylate to a hot solvent mixture of 56 grams of Dowanol PM and 17.1 grams of diacetone alcohol. Prepared by dissolving. 0.5 grams of Tinuvin 1130 and 0.3 grams of Tinuvin 900
A solution containing 2.5 grams of toluene was prepared.

Silane-PVP type abrasion resistant coatings were prepared by the methods described in Examples 8 and 9. The brider was drop coated onto the polycarbonate and then dried at 100°C for 30 minutes. The abrasion resistant film is also flow coated and 1
Cured for 20 minutes at 20°C. Brimer'! The moisture resistance of the & coating reflects the compatibility of the organic acrylic matrix and the U absorbent, and the overall moisture resistance is 65.6℃, 100%.
The condensation humidification test results are shown in the Example 6 column of the table below.

Table 2 Note: + indicates “brimer + side abrasive coating”.

Example 13 A silane-alumina type abrasion resistant coating was prepared containing the following ingredients. 62 grams of 5% alumina sol in water, 75
grams of methyltriethoxysilane, 5 grams of dimethyljethoxysilane, 2 grams of acetic acid, 18 grams of diacetone alcohol, and 18 grams of 2-propanol.

Clean polycarbonate was coated with the WJ solution of Example 11 and dried for 30 minutes at 100°C. The silane-alumina solution was drop coated onto the brimered polycarbonate surface, air dried for 15 minutes, and then cured at 120 DEG C. for 2 hours. Coated polycarbonate has excellent abrasion resistance, 8.0 percent haze after 300 cycles of Bayer abrasion testing, 700
It showed only 3.0 YID of yellowing after exposure to Q-tJVB for hours. No haze appeared on the w1 cover after 1200 hours of exposure to 65.6° C. and 100% relative humidity.

The embodiments described above are provided to illustrate the invention. The various hydrolyzable alkoxide and hydrophilic hydroxybenzophenone and/or hydroxybenzotriazole compositions have sufficient alkoxides therein to form an oxide network, and the U absorption spectrum of the coating on the quartz substrate As measured, combinations can be made in a wide range of ratios and concentrations, as long as there is sufficient hydrophilic UV absorber to give the desired improvement in UV resistance without compromising the abrasion resistance of the coating.

Various organic polymers and organic UV absorbers can be mixed in a wide range of ratios and concentrations with various additive solvents, such as aromatic solvents such as xylene, to enhance adhesion to organic substrates. According to the invention, these coatings are useful on a variety of substrates and with a variety of abrasion resistant coatings, the scope of which is defined by the following claims.

Claims (20)

[Claims] (1) An optically transparent coating composition for protecting a substrate from ultraviolet light, comprising: a, partially hydrolyzed alkoxide of the general formula R_XM(OR')_Z_-_X. where R is an organic radical, M is selected from silicon, aluminum, titanium, zirconium, cerium and mixtures thereof, R' is a low molecular weight alkyl radical, Z is the valence of M, and X is It may be less than Z or may be zero. b. Hydroxy-containing organic compounds that absorb ultraviolet radiation and contain hydrophilic moieties. (2) The composition according to claim (1), wherein the alkoxide has the general formula R_XSi(OR')_4_-_X
and R' is selected from the group consisting of methyl, ethyl, propyl and butyl, R is selected from the group consisting of alkyl, vinyl, phenyl, methoxyethyl, γ-glycidoxypropyl and γ-methacryloxypropyl, and a composition characterized in that X is 1. (3) The composition according to claim (1), wherein the hydroxy-containing organic compound comprises hydroxybenzotriazole or hydroxybenzophenone having a hydrophilic moiety selected from the group consisting of ethoxylates and propoxylates. A composition characterized by: (4) A method of preparing an optically clear ultraviolet ray resistant coating composition comprising the steps of: a. At least partially hydrolyzing the alkoxide of the general formula R_XM(OR')_Z_-_X. In the formula R
is an organic radical, M is selected from the group consisting of silicon, aluminum, titanium, zirconium, cerium, and mixtures thereof, R' is a low molecular weight alkyl radical, Z is the valence of M, and X is It may be less than Z or may be zero. b. Adding to the at least partially hydrolyzed alkoxide a hydroxy-containing organic compound that absorbs ultraviolet radiation and contains a hydrophilic moiety. (5) The method of claim (4), wherein said alkoxide has the general formula R_XSi(OR')_4_-_X and R' is selected from the group consisting of methyl, ethyl, propyl and butyl; R is alkyl, vinyl,
A method selected from the group consisting of phenyl, methoxyethyl, γ-glycidoxypropyl and γ-methacryloxypropyl, and characterized in that X is 1. (6) The method according to claim (4), wherein the hydroxy-containing organic compound comprises a hydroxybenzotriazole or hydroxybenzophenone having a hydrophilic moiety selected from the group consisting of ethoxylates and propoxylates. How to characterize it. (7) Optically transparent, UV resistant, and abrasion resistant coated articles comprising: a. a transparent solid polymeric substrate; b. a UV-resistant and abrasion-resistant coating which is a reaction product of the hydrolytic polycondensation of a metal alkoxide of the general formula R_XM(OR')_Z_-_X; Hydroxy-containing organic compounds that absorb However, in the above general formula, R is an organic radical, M is selected from the group consisting of silicon, aluminum, titanium, zirconium, cerium, and mixtures thereof, R' is a low molecular weight alkyl radical, and Z is the valence of M. , and X is less than Z and may be zero. (8) The article according to claim (7), wherein R' is selected from the group consisting of methyl, ethyl, propyl, and butyl, and R is alkyl, vinyl, phenyl, methoxyethyl, γ-glycidoxypropyl. and γ-methacryloxypropyl, and X is 1, and the substrate is polycarbonate. (9) The article according to claim (8), wherein the hydroxy-containing organic compound consists of hydroxybenzophenone and hydroxybenzotriazole containing a hydrophilic moiety selected from the group consisting of ethoxylates and proxylates. An article characterized by being selected from a group. (10) An optically transparent coating composition for protecting plastic substrates from ultraviolet light, comprising: a. an organic compound that absorbs ultraviolet light; b. a polymer comprising a mixture of alkyl acrylates; and c. a solvent that reacts with the plastic substrate to promote adhesion of the coating composition to the plastic substrate. (11) The composition according to claim (10), wherein the organic compound includes a hydroxy-containing compound. (12) The composition according to claim (11), wherein the hydroxy-containing organic compound contains hydroxybenzophenone or hydroxybenzotriazole. (13) The composition according to claim (10), wherein the solvent contains propylene glycol methyl ether. (14) The composition according to claim (13), wherein the solvent further contains toluene. (15) Optically transparent, ultraviolet ray resistant coated articles comprising: A transparent UV-resistant coating comprising: a. an optically polymerized substrate; b. 1) an organic compound that absorbs UV radiation; and 2) a film-forming polymer comprising a mixture of alkyl acrylates. (16) The article according to claim (15), wherein the substrate is made of polycarbonate. (17) The article of claim (15), wherein the coating comprises a hydroxy-containing organic compound that absorbs ultraviolet light. (18) The article according to claim (11), wherein the organic compound is selected from the group consisting of hydroxybenzophenone and hydroxybenzotriazole. (19) The article of claim (15), wherein the film-forming polymer is poly(methyl methacrylate).
or an article characterized by containing poly(ethyl methacrylate). (20) The article according to claim (15), further comprising an abrasion-resistant coating that is a reaction product of hydrolytic polycondensation of a metal alkoxide.