Non-fogging coating composition and a shaped article coated therewith

Abstract

A non-fogging coating composition, which comprises (A) 0 to 50 parts by weight of epoxy group-containing organic silane compounds or partial hydrolyzates thereof, (B) 20 to 80 parts by weight of a polyhydric alcohol having an ethylene oxide chain, (C) 10 to 75 parts by weight of a polymer or copolymer having at least 20% by weight of repeating structural units having the general formula ##STR1## wherein, R⁴ and R⁵ independently stand for H or a lower alkyl group or carbonyl group and X stands for a side chain possessing an epoxy group, and (D) a catalytic amount of a curing catalyst. And a shaped article of polycarbonate type resin coated therewith.

Description

BACKGROUND OF THE INVENTION

1. Fields of the Invention

This invention relates to a non-fogging coating composition for the formation of coating films excelling in non-fogging property or proofness against haze and resistance to scratch or to wear as well as weatherability and to shaped articles of polycarbonate type resins coated with the composition mentioned above. More particularly, this invention relates to a non-fogging coating composition excelling in non-fogging property, resistance to scratch and weatherability, and to coated shaped articles of polycarbonate type resins which are produced by forming substrates of polycarbonate type resins, coating the substrates with an undercoat of good adherency to the substrates, allowing the undercoat to set, then applying the non-fogging coating composition mentioned above as an overcoat to the set undercoat and allowing the overcoat to set and which, therefore, combines high resistance to scratch and good non-fogging property.

2. Description of the Prior Art

The fault found with plastics, inorganic glasses, etc. which heretofore have been used as transparent materials is the fact that when their surface temperature falls below the dew point of the ambient air, their surfaces are fogged and consequently deprived of transparency even to an extent of causing a serious inconvenience. Various studies and experiments, therefore, have been made in search of a method capable of forming a non-fogging coat on the surface of such transparent materials.

It has been known to form such a coat by using a composition made preponderantly of a polymer of a hydroxyethyl methacrylate or polyvinyl alcohol, for example. This and all other non-fogging coating compositions heretofore put to trial are fairly satisfactory in terms of non-fogging property. Nevertheless, they are highly susceptible to injuries and destitute of scratch resistance and weatherability. The disadvantage has prevented them from being put to practical use.

Generally, polycarbonate type resins excel in impact resistance and transparency. They nevertheless have a disadvantage that they offer poor resistance to scratch and the action of solvents and readily sustain injuries on the surface and yield to organic solvents. Moreover, when the resin surface temperature falls below the dew point of the ambient air, the surface is fogged and deprived of transparency at times to an extent of causing no small inconvenience. To remedy the various diadvantages pointed out above, coating methods aimed at forming various coating films on their surface have been studied. None of them, however, have succeeded in providing a coating film which combines high resistance to scratch and non-fogging property and, at the same time, excels in adherency to substrates.

It is, therefore, an object of this invention to provide a coating composition which is capable of forming a coating film possessing non-fogging property and combining scratch resistance and weatherability.

Another object of this invention is to provide shaped articles of coated polycarbonate type resins excelling in resistance to scratch and non-fogging property as well as adherency of the coats to the substrates.

A further object of this invention is to provide a method for the manufacture of coated polycarbonate type resins which excel in resistance to scratch and non-fogging property as well as adherency of the coats to the substrates.

SUMMARY OF THE INVENTION

The objects described above are accomplished by the provision of a non-fogging coating composition, which comprises:

(A) 0 to 50 parts by weight ##STR2## of at least one compound selected from the group consisting of epoxy group-containing organic silane compounds represented by the general formula (1): ##STR3## wherein, R¹ stands for an organic group having an epoxy group, R² for a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms or a vinyl group, R³ for a hydrocarbon group having 1 to 5 carbon atoms, an alkoxyalkyl group or an acyl group having 1 to 4 carbon atoms, a for an integer having the value of 1 to 3 and b for an integer having the value of 0 to 2, providing that a+b≦3 is satisfied, and partial hydrolyzates thereof,

(B) 20 to 80 parts by weight of a polyhydric alcohol having an ethylene oxide chain,

(C) 10 to 75 parts by weight of a polymer or copolymer containing at least 20% by weight of repeating structural units represented by the general formula (2): ##STR4## wherein, R⁴ and R⁵ independently stand for a hydrogen atom, a lower alkyl group or a carboxyl group and X stands for a side chain possessing an epoxy group, and

(D) a catalytic amount of a curing catalyst, providing that the total of the amounts of the aforementioned components (A), (B) and (C) is 100 parts by weight.

The coated shaped article of a polycarbonate type resin which combines resistance to scratch and non-fogging property comprises:

(I) a substrate of a polycarbonate type resin,

(II) a layer of undercoat formed by applying to the surface of the substrate and allowing to cure thereon a composition containing a polymer selected from the group consisting of:

(i) a polymer possessing repeating structural units represented by the general formula (3): ##STR5## wherein, R⁶ and R⁷ independently stand for a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a carboxyl group and Y stands for a side chain containing a carboxyl group, an amino group or an epoxy group, and

(ii) a polymer possessing repeating structural units represented by the formula (4): ##STR6## wherein, R⁸ and R⁹ independently stand for a hydrogen atom, a lower alkyl group or a carboxyl group and Z stands for a side chain containing a hydroxyl group, and repeating structural units represented by the formula (5): ##STR7## wherein, R¹0 and R¹1 independently stand for a hydrogen atom, a lower alkyl group or a carboxyl group and W stands for a side chain containing a carboxyl group, an alkoxycarbonyl group, an amino group, a substituted amino group, an epoxy group or a tetrahydrofuryl group, and

(III) a layer of overcoat formed by applying to the surface of the undercoat and allowing to cure thereon a non-fogging coating composition, comprising:

(A) 0 to 50 parts by weight ##STR8## of at least one compound selected from the group consisting of epoxy group-containing organic silane compounds 2-(N,N-dimethylamino)ethyl 2-(N,N-dimethylamino)ethyl (meth)acrylate, 2-(N,N-diethylaminoethyl) (meth)acrylate, 2-(N,N-dibutylamino)ethyl (meth)acrylate, 3-(N,N-diethylamino)propyl (meth)acrylate, 2-(N,N-dibutylamino)propyl (meth)acrylate, 3-N,N-dibutylamino)propyl 3-(N,N-dibutylamino)propyl (meth)acrylate; (meth)acryl glycidyl ether, allyl glycidyl ether, glycidyl (meth)acrylate, glycidyl crotonate; and tetrahydrofurfuryl (meth)acrylate. These vinyl monomers (iv) may be used either independently of one another or in the form of a mixture of two or more members. The polymer (ii) may be used solely or in combination with one or more as undercoat.

Of these compositions, the one containing a polymer (ii) respectively having repeated structural units shown by the general formula (4) and (5) as a main component is especially preferable.

Of these vinyl monomers (iii) constituting the above-mentioned polymer (ii), the especially preferable ones are N-hydroxymethy (meth)acrylamide, N-(2-hydroxyethyl) (meth)acrylamide, N,N-dihydroxymethyl (meth)acrylamide, N,N-di(2-hydroxyethyl) (meth)acrylamide, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 1,4-butyleneglycol mono(meth)acrylate, polyethyleneglycol mono(meth)acrylate, polypropyleneglycol mono(meth)acrylate and the like. Further, of these vinyl monomers (iv), the especially preferable ones are methyl (meth)acrylate, ethyl(meth)acrylate, 2-(N-methylamino)ethyl (meth)acrylate, 2-(ethylamino)ethyl (meth)acrylate, 2-(N,N-dimethylamino)ethyl (meth)acrylate, 2-(N,N-diethyl(amino)ethyl (meth)acrylate, 2-(N,N-dibutylamino)ethyl (meth)acrylate, 3-(N,N-diethylamino)propyl (meth)acrylate, 2-(N,N-dibutylamino) propyl (meth)acrylate, 3-(N,N-dibutylamino)propyl (meth)acrylate, allyl glycidylether, glycidyl (meth)acrylate, glycidyl crotonate, tetrahydrofurfuryl (meth)acrylate and the like.

The aforementioned undercoating composition is not always required to incorporate a cross-linking agent. When the overcoat is applied to the undercoat, there is a possibility that the organic solvent contained in the overcoat will pass into the undercoat even to an extent of notably degrading the adhesiveness of the overcoat. To preclude this possibility, therefore, it is desirable that the undercoat should contain enough cross-linking agent to intercept the otherwise possible invasion of the organic solvent. Examples of cross-linking agents which are usable in the undercoat composition include polyhydric alcohols such as 1,4-butane diol, glycerol, and polyethylene glycol; melamines such as methylol melamine and alkyl-etherified methylol melamines; polyfunctional epoxy compounds such as ethylene glycol diglycidyl ether, glycerol polyglycidyl ether; alkoxysilane having epoxy group and hydrolyzate. Of these cross-linking agents, particularly desirable are alkyl-etherified methylol melamines such as hexa(methoxymethyl) melamine and hexa(butoxymethyl) malamine. These cross-linking agents may be used either independently of one another or in the form of a mixture of two or more members. When alkyl-etherified methylol melamines are used, the amount of the cross-linking agent to be used in this invention falls in the range of from 0.05 to 0.7 equivalent weight, preferably from 0.1 to 0.4 equivalent weight, based on one equivalent weight of the functional group (carboxylic group, amino group, substituted amino group, hydroxyl group, epoxy group or tetra-hydroxyl group) present in the aforementioned polymer (i) or polymer (ii).

Examples of the cross-linking catalyst usable with the cross-linking agent described above include hydrochloric acid, ammonium chloride, ammonium nitrate, ammonium thiocyanate, ammonium perchlorate, triethylamine, N,N-dimethylamino propylamine and stannous octoate. Generally, the amount of the cross-linking catalyst to be used falls within the range of from 0.05 to 0.8 gram equivalent to 1 gram equivalent of the cross-linking agent. The cross-linking catalyst may be used without the cross-linking agent.

The undercoating composition, immediately before use, is diluted to a concentration befitting the work of application to the substrate. Examples of diluents usable for this purpose include methanol and other alcohols, methyl cellosolve and other ethers, methylethyl ketone and other ketones, and methyl acetate and other esters. These diluents may be used either independently of one another or in the form of a mixture of two or more members. The extent of this dilution is desired to be such that the concentration of the aformentioned polymer (i) or polymer (ii) falls within the range of from 0.1 to 25 by weight, preferably from 0.5 to 15% by weight.

Optionally, the undercoating composition may contain therein an ordinary paint additive such as a flow control agent in a small amount.

The undercoat film can be formed on the shaped substrate of a polycarbonate type resin by preparing a composition consisting preponderantly of the aforementioned polymer (i) or polymer (ii) and optionally incorporating therein a cross-linking agent, a cross-linking catalyst, a diluent and a flow control agent, applying this composition to the surface of the shaped substrate, drying the resultant layer of composition and optionally treating the dried undercoat layer at a temperature lower than the temperature at which the shaped resin substrate is thermally deformed. The thickness of the undercoat film is desired to fall within the range of from 0.1 to 3 micron.

Now, the present invention will be described further in detail with reference to working examples, which are illustrative of and not limitative in the least of this invention. In the examples, the non-fogging property was determined by first retaining a given test piece at -10°C, then allowing it to stand in an atmosphere under the conditions of 22°C and 60% of RH and noting whether or not the surface of the test piece was fogged. The resistance to scratch was determined by rubbing a given test piece with a brass wire brush (of the type having whiskers implanted in four rows) and noting how difficult it was for the brush to inflict scratches to the surface. This resistance was rated on the A-B-C scale, wherein:

A stands for perfect resistance such that no scratches were inflicted even by strong rubbing.

B stands for fair resistance such that scratches were slightly inflicted by strong rubbing.

C stands for poor resistance such that scratches were inflicted even by weak rubbing.

The resistance to hot water was determined by immersing a given test piece under boiling water for one hour and examining it in open air to note whether or not the condition of the film was affected by the boiling water.

EXAMPLES 1-10 and CONTROLS 1-6

(1) Preparation of solution of partial hydrolyzate of γ-glycidoxypropyl trimethoxy silane (A-1)

In 68.4 parts of ethyl cellosolve was dissolved 100.0 parts of γ-glycidoxypropyl trimethoxy silane. To the solution, 34.2 parts of an aqueous 0.1N hydrochloric acid solution was gradually added. The mixture was stirred at room temperature to induce hydrolysis. Thereafter, the resultant mixture was allowed to stand and age at room temperature for more than 20 hours. The solution consequently obtained was colorless and transparent and was found to contain 35% by weight of the γ-glycidoxy-propyl trimethoxy silane hydrolyzate calculated as ##STR22## (2) Preparation of solution of partial hydrolyzate of β-(3,4-epoxy-cyclohexyl)ethyl trimethoxy silane (A-2)

In 73.2 parts of ethyl cellosolve was dissolved 100.0 parts of β-(3,4-epoxy-cyclohexyl)ethyl trimethoxy silane. To the solution, 32.8 parts of an aqueous 0.01N hydrochloric acid solution was gradually added. The mixture was stirred at room temperature to induce hydrolysis. Thereafter, the resultant mixture was allowed to stand and age at room temperature for more than 20 hours. The solution consequently obtained was colorless and transparent and was found to contain 35% by weight of β-(3,4-epoxy-cyclohexyl)ethyl trimethoxy silane hydrolyzate calculated as ##STR23## (3) Preparation of solution of partial cohydrolyzate of γ-glycidoxypropyl trimethoxy silane and β-(3,4-epoxycyclohexyl)ethyl trimethoxy silane (A-3)

In 70.2 parts of ethyl cellosolve were dissolved 70 parts of γ-glycidoxypropyl trimethoxy silane and 30 parts of β-(3,4-epoxy-cyclohexyl)ethyl trimethoxy silane. To the solution, 34.0 parts of an aqueous 0.1N hydrochloric acid solution was gradually added. The mixture was stirred at room temperature to include hydrolysis. Thereafter, the resultant mixture was allowed to stand and age at room temperature for more than 20 hours. The solution consequently obtained was colorless and transparent and was found to contain 24.3% by weight of γ-glycidoxypropyl trimethoxysilane hydrolyzate calculated as ##STR24## 10.6% by weight of γ-(3,4-epoxy-cyclohexyl)ethyl trimethoxy silane hydrolyzate calculated as ##STR25## (4) Unhydrolyzed γ-glycidoxy-propyl trimethoxy silane (A-4) (5) Polyhydric alcohols containing an ethylene oxide chain (B-1 through B-4), indicated in Table 1 below.

TABLE 1
______________________________________
Solution Polyhydric alcohol containing
Molecular
No.      ethylene oxide chain
weight
______________________________________
B-1      Polyoxyethylated glycerol
520
B-2      Polyoxyethylated sorbitol
850
B-3      Polyoxyethylated sorbitol
2500
B-4      Polyethylene glycol
300
______________________________________

(6) Preparation of solution of copolymer of glycidyl methacrylate (60 parts by weight) and hydroxyethyl methacrylate (40 parts by weight) (C-1)

To 140 g of ethyl cellosolve were added 36 g of glycidyl methacrylate, 24 g of hydroxyethyl methacrylate and 3.0 g of azo-bis-isobutyronitrile (AIBN). The mixture was gently stirred and heated up to 90°C During this treatment, nitrogen was continuously blown into the reaction system for about four hours. Consequently obtained was a light yellow solution measuring approximately 90 centipoises in viscosity (molecular weight about 20,000). Thus, a copolymer of glycidyl methacrylate and hydroxyethyl methacrylate was formed.

(7) Preparation of solution of copolymer of 3,4-epoxybutyl methacrylate (70 parts by weight), methyl methacrylate (15 parts by weight) and hydroxyethyl methacrylate (15 parts by weight) (C-2)

To 140 g of ethyl cellosolve were added 42 g of 3,4-epoxybutyl methacrylate,9, 9 g of methyl methacrylate, 9 g of hydroxyethyl methacrylate and 0.3 g of AIBN. The mixture was gently stirred and heated up to 90°C During this treatment, nitrogen was continuously blown into the reaction system for more than about four hours. Consequently obtained was a light yellow solution measuring approximately 80 CPS in viscosity (molecular weight about 18,000). Thus a copolymer of 3,4-epoxybutyl methacrylate, methyl methacrylate and hydroxyethyl methacrylate was formed.

(8) Preparation of solution of copolymer of glycidyl methacrylate (15 parts by weight), ethyl methacrylate (50 parts by weight) and hydroxyethyl methacrylate (35 parts by weight) (C-3)

To 140 g of ethyl cellosolve were added 9 g of glycidyl methacrylate, 30 g of ethyl methacrylate, 21 g of hydroxyethyl methacrylate and 0.3 g of AIBN. The mixture was gently stirred and heated up to 90°C During this treatment, nitrogen was continuously blown into the reaction system for about four hours. Consequently obtained was a light yellow solution measuring about 100 CPS in viscosity (molecular weight about 20,000). Thus, a copolymer of glycidyl methacrylate, ethyl methacrylate and hydroxyethyl methacrylate was formed. This copolymer contained 15% by weight of repeating structural units represented by the general formula ##STR26## (9) Ammonium perchlorate (D-1) and aluminum acetyl acetonate (D-2) were used as the curing catalyst.

(10) Of the various nonionic active agents, an active agent of the polyoxyethylene alkyl aryl type (produced by Lion Oils and Fats Co., and marketed under trademark designation of Liponox NCN) (E-1) and an active agent of the polyoxyethylene sorbitane ester type (produced by Nippon Oils and Fats Co., and marketed under trademark designation of Nissan Nonion LT-221) (E-2) were used as the surface active agent.

(11) Preparation of paints

The epoxy group-containing organic silane compounds and/or partial hydrolyzates thereof (A-1 through A-4), the polyhydric alcohols containing an ethylene oxide chain (B-1 through B-4) and the vinyl polymers or copolymers containing an epoxy group (C-1 through C-3) mentioned above were mixed in the varying proportions indicated in Table 2, with the curing catalysts (D-1 and D-2) and optionally the surface active agents (E-1 and E-2) added thereto in the proportions also indicated in Table 2 and a flow control agent further added thereto in small amount. The resultant mixtures were diluted with ethyl cellosolve so that their solids contents fell within the range of from 20 to 50% by weight.

(12) Coating

Diethylene glycol bis-allyl carbonate plates 3 mm in thickness washed in advance were coated with the paints mentioned above by the immersion method and were heated at 130°C for one hour to cure the applied coats.

The films were tested for properties. The results are collectively shown in Table 2.

TABLE 2
__________________________________________________________________________
Example
Component (A)
Component (B)
Component (C)
Curing Catalyst
No.   Code
Weight
Code
Weight
Code
Weight
Code
Weight
__________________________________________________________________________
Example 1
A-1
28.6(10)
B-1
50(50)
C-1 133.3(40)
D-1
1.0
Example 2
A-2
114.3(40)
B-2
40(40)
C-1 66.6(20)
D-1
1.0
Example 3
A-3
85.7(30)
B-2
30(30)
C-1 133.3(40)
D-1
1.0
Example 4
A-1
57.1(20)
B-2
50(50)
C-1 100(30)
D-2
1.0
Example 5
A-1
57.1(20)
B-4
60(60)
C-1 66.6(20)
D-2
1.0
Example 6
A-1
114.3(40)
B-1
30(30)
C-2 100(30)
D-1
1.0
Example 7
A-1
57.1(20)
B-2
30(30)
C-2 166.6(50)
D-1
1.0
Example 8
A-3
57.1(20)
B-1
40(40)
C-1 133.3(40)
D-1
1.0
Example 9
A-4
171.4(60)
B-2
--   C-1 166.6(50)
D-1
1.0
Control 1
A-1
171.4(60)
--   C-1 133.3(40)
D-1
1.0
Control 2
--    B-2
50(50)
C-2 166.6(50)
D-1
1.0
Control 3
A-1
171.4(60)
B-1
20(20)
C-1 66.6(20)
D-1
1.0
Control 4
A-1
28.6(10)
B-1
80(80)
C-1 33.3(10)
D-1
1.0
Control 5
A-1
28.6(10)
B-2
10(10)
C-1 266.7(80)
D-1
1.0
Example 10
A-1
57.1(20)
B-3
50(50)
C-1 100(30)
D-1
1.0
Control 6
A-1
85.7(30)
B-2
50(50)
C-3 66.6(20)
D-1
1.0
__________________________________________________________________________
Resistance to
Surface                   hot water
Example
active agent
Non-fogging
Resistance   Resistance
No.   Code
Weight
property
to scratch
Appearance
to wear
__________________________________________________________________________
Example 1    No fogging
A     Normal A
formed
Example 2    No fogging
A     "      A
formed
Example 3    No fogging
A     "      A
formed
Example 4    No fogging
A     "      A
formed
Example 5    No fogging
A-B   "      A-B
formed
Example 6
E-1
15.0
No fogging
A     "      A
formed
Example 7
E-2
10.0
No fogging
A     "      A
formed
Example 8
E-1
10.0
No fogging
A     "      A
formed
Example 9    No fogging
A     "      A
formed
Control 1    fogging
A     "      A
formed
Control 2    No fogging
B     "      B-C
formed
Control 3    fogging
A     Rough  A
formed       surface
Control 4
E-1
10.0
No fogging
C            C
formed
Control 5    fogging
No smooth
--     --
formed film formed
Example 10   No fogging
A-B   Normal B
formed
Control 6    No fogging
B     "      B
formed
__________________________________________________________________________
The numeral values in parentheses are weight proportions based on the
total of compoonents taken as 100.

EXAMPLE 11

A non-fogging substrate produced by faithfully following the procedure of Example 7 was kept at a distance of about 50 mm from a container holding therein an anthraquinone type disperse dye (produced by Sumitomo Chemical Industry Co., Ltd., and marketed under trademark designation of Sumikalon Blue E-FBL) finely pulverized in advance with a mortar.

A bell jar placed to cover the substrate and the dye container was closed airtightly and evacuated of the inner air by a vacuum pump to a pressure of 0.5 Torrs. The heater for the dye container was switched on to raise the temperature of the container up to 200°C and hold it at that temperature for 10 minutes to vaporize the dye. The coated substrate set in position within the bell jar was rotated about its center at a constant rate of 60 turns per minute within the vapor of the dye to preent prevent the film from being unevenly colored. Consequently there was obtained a substrate having an evenly dyed blue, non-fogging coat on one surface thereof. This substrate possessing a blue, non-fogging coat showed the same degrees of non-fogging property, scratch resistance and hot-water resistance as that obtained in Example 7. In the color fastenss fastness test (JIS L-0842-1971) (hereinafter referred to as "fade test") conducted under the light of a carbon arc for 200 hours, the substrate retained perfect color fastness showing substantially no sign of fading.

EXAMPLE 12

A non-fogging substrate produced by faithfully following the procedure of Example 6 was immersed in a dye bath containing 90 g of a polyoxyethylene alkyl aryl type surface active agent (produced by Lion Oils and Fats Co., Ltd., and marketed under trademark designation of Liponox NCO) and 10 g of an anthraquinone type disperse dye (produced by Sumitomo Chemical Industry Co., Ltd., and marketed under trademark designation of Sumikalon Blue E-FBL), at 95°C for five minutes. Consequently, there was obtained a substrate possessing a uniformly dyed, transparent blue coat. This substrate possessing a colored, non-fogging coat showed the same degrees of non-fogging, scratch resistance and hot-water resistance as the substrate of Example 6. After a 200 hours' fade test, it retained perfect color fastness showing substantially no sign of fading.

EXAMPLES 13-24 and CONTROLS 7-10

The polymers or copolymers possessing an epoxy group (C-1 through C-3), the polyhydric alcohols possessing an ethylene oxide chain (B-1 through B-4) and the curing catalysts (D-1 and D-2) prepared by faithfully following the procedure of Examples 1-10, and optionally cross-linking agents containing an epoxy group (F-1 thorugh through F-7) indicated in Table 3 and surface active agents (E-1 and E-2) were mixed in the varying proportions shown in Table 4, with a flow control agent added thereto in a small amount. The resultant mixture was diluted with ethyl cellosolve so that the solids content fell within the range of from 20 to 50% by weight. Thus, paints were obtained.

Diethylene glycol bisallyl carbonate plates 3 mm in thickness cleaned in advance were coated with the paints mentioned above by the immersion method. The coats on the substrates were cured by heating at 130° C. for one hour. The coats were tested for properties. The results are shown collectively in Table 4.

TABLE 3
______________________________________
Trademark
Code designation
Structure         Producer
______________________________________
F-1  Sumi-epoxy
Bis-phenol A-epichloro-
Sumitomo
ELA-128   hydrin type       Chemical
Industry Co.,
Ltd.
F-2  Sumi-epoxy
Bis-phenol A-epichloro-
Sumitomo
ESA-014   hydrin type       Chemical
Industry Co.,
Ltd.
F-3  Denacol   Glycerol polyglycidyl ether
Nagase Sangyo
ES-313                      Co., Ltd.
F-4  Denacol   Sorbitol polyglycidyl ether
Nagase Sangyo
EX-611                      Co., Ltd.
F-5  Epolite   Trimethylol propane poly-
Kyoeisha Oils
100 MF    glycidyl ether    and Fats Co.,
F-6  Chissonox Cyclohexene oxide type
Chisso Co.,
221                         Ltd.
F-7  Sumi-epoxy
N,N,N',N'--tetraglycidyl
Sumitomo
ELM-434   DDM               Chemical
Industry
Co., Ltd.
______________________________________

TABLE 4
__________________________________________________________________________
Cross-linking
Curing
Example
Component (C)
Component (B)
Agent    catalyst
No.   Code
Weight
Code
Weight
Code
Weight
Code
Weight
__________________________________________________________________________
Example 13
C-1
150(45)
B-1
55(55)
F-1 11(11)
D-1
1.1
Example 14
C-1
110(33)
B-2
67(67)
F-2 67(67)
D-1
1.7
Example 15
C-1
167(50)
B-2
50(50)
F-3 25(25)
D-1
1.3
Example 16
C-1
83(25)
B-4
75(75)
F-3 25(25)
D-1
1.3
Example 17
C-2
167(50)
B-2
50(50)
F-4 67(67)
D-1
1.7
Example 18
C-2
210(63)
B-2
37(37)
F-5 25(25)
D-1
1.3
Example 19
C-2
183(55)
B-1
45(45)
F-5 11(11)
D-1
1.1
Example 20
C-1
190(57)
B-1
43(43)
F-6 43(43)
D-2
1.4
Example 21
C-1
127(37)
B-1
63(63)
F-7 25(25)
D-1
1.2
Example 22
C-1
167(50)
B-2
50(50)
--  --   D-1
1.0
Example 23
C-2
200(60)
B-2
40(40)
--  --   D-1
1.0
Control 7
C-1
267(80)
B-1
20(20)
--  --   D-1
1.0
Control 8
C-2
33(10)
B-1
90(90)
--  --   D-1
1.0
Control 9
C-1
37(11)
B-1
89(89)
F-6 11(11)
D-1
1.1
Example 24
C-1
143(43)
B-3
57(57)
F-3 43(43)
D-1
1.4
Control 10
C-3
167(50)
B-1
50(50)
F-4 25(25)
D-1
1.2
__________________________________________________________________________
Resistance to
Surface active            hot water
Example
Agent  Non fogging
Resistance   Resistance
No.   Code
Weight
property
to scratch
Appearance
wear
__________________________________________________________________________
Example 13   No-fogging
A     Normal A
formed
Example 14   No-fogging
A-B   "      A-B
formed
Example 15   No-fogging
A     "      A
formed
Example 16
E-1
13  No-fogging
A-B   "      A-B
formed
Example 17
E-1
26  No-fogging
A     "      A
formed
Example 18   No-fogging
A     "      A
formed
Example 19
E-2
11  No-fogging
A     "      A
formed
Example 20   No-fogging
A     "      A
formed
Example 21   No-fogging
A-B   "      A-B
formed
Example 22   No-fogging
A-B   "      A-B
formed
Example 23   No-fogging
A     "      A-B
formed
Control 7    fogging
A     "      A
formed
Control 8    No fogging
C     Rough  C
formed       surface
Control 9    No fogging
C     Rough  C
formed       surface
Example 24   No fogging
A-B   Normal B
formed
Control 10   No fogging
B     "      B-C
formed
__________________________________________________________________________
The numerical values in parentheses are proportions of solids content
polymerized, based on the total of (C) + (B) taken as 100.

EXAMPLE 25

A paint was prepared by following the procedure of Example 15 of Table 4, except that a mixture of 12.5 parts by weight of the cross-linking agent F-3 and 12.5 parts by weight of a hydrolyzate of γ-glycidoxypropyl trimethoxy silane (calculated as RSiO₁.5) was used in the place of 25 parts by weight of cross-linkg cross-linking agent F-3. A diethylene glycol bisallyl carbonate plate 3 mm in thickness cleaned in advance was coated with this paint by the immersion method. The coat thus formed was cured by heating at 130°C for one hour. In the test for non-fogging property, resistance to scratch and resistance to hot water, this coat showed good results.

EXAMPLE 26

A non-fogging substrate produced by faithfully following the procedure of Example 19 was kept at a distance of about 50 mm from a dye container holding therein an anthraquinone type disperse dye (produced by Sumitomo Chemical Industry Co., Ltd., and marketed under trademark designation of Sumikalon E-FBL) finely pulverized in advance.

A bell jar was placed to cover the coated substrate and the dye container, closed airtightly and evacuated of the inner air by a vacuum pump to a pressure of 0.5 Torrs. Then the heater for the dye container was switched on to raise the container's temperature up to 200°C and hold it at that level for 10 minutes to vaporize the dye. The non-fogging substrate set in position within this bell jar was rotated about its center at a constant rate of 60 turns per minute in the vapor of the dye so as to prevent the film from being unevenly dyed. Consequently there was obtained a substrate having a uniformly colored, blue non-fogging film on one surface thereof. The substrate possessing the colored non-fogging coat showed the same degree of non-fogging, scratch resistance and hot-water resistance as the coated substrate of Example 19. After a 200 hours' fade test, it retained perfect color fastness showing substantially no sign of fading.

EXAMPLE 27

A non-fogging substrate produced by faithfully following the procedure of Example 18 was immersed in a dye bath consisting of 90 g of a polyoxy-ethylene alkyl aryl type surface active agent (produced by Lion Oils and Fats Co., Ltd., and marketed under trademark designation of Liponox NCO) and 10 g of an anthraquinone type disperse dye (produced by Sumitomo chemical Industry Co., Ltd., and maketed under trademark designation of Sumikalon blue E-FBL) at 95°C for five minutes. Consequently there was obtained a substrate having a uniformly dyed, blue transparent non-fogging coat. This substrate having the dyed, non-fogging coat possessed the same degree of non-fogging scratch resistance and hot-water resistance as the coated substrate of Example 18. After a 200 hours fade test, it retained perfect color fastness showing substantially no fading.

EXAMPLES 28-37 and CONTROLS 11-13

PAC A. Undercoat Layer

(1) Preparation of solution of copolymer of 2-hydroxyethyl methacrylate (36 parts by weight), dimethylamino-ethyl mathacrylate (14 parts by weight) and methyl methacrylate (50 parts by weight) (U-1)

To 320 g of ethyl cellosolve were added 36 g of 2-hydroxyethyl methacrylate, 14 g of dimethylaminoethyl methacrylate, 50 g of methyl methacrylate and 0.4 g of azo-bis-isobutyronitrile. The resultant mixture was stirred under an atmosphere of nitrogen at 90°C for four hours to effect copolymerization of the monomers. Thus was obtained a light yellow solution having a molecular weight of about 22,000. A copolymer of 2-hydroxyethyl methacrylate, dimethylaminoethyl methacrylate and methyl methacrylate was thus obtained.

(2) Preparation of Other Copolymers and Homopolymer (U-2 through U-6)

The various copolymers or homopolymer, U-2 through U-6, indicated in Table 5 were prepared by following the procedure of (1).

TABLE 5
__________________________________________________________________________
Parts by     Parts by  Parts by
Type       weight
Type    weight
Type weight
__________________________________________________________________________
U-2
2-Hydroxyethyl
95   Dimethylamino-
5    --   --
methacrylate ethyl
methacrylate
U-3
2-Hydroxyethyl
51.5 Acrylic acid
28.5 --   --
methacrylate
U-4
2-Hydroxyethyl
38   Glycidyl
42   --   --
methacrylate methacrylate
U-5
Acrylamide
50   --      --   --   --
U-6
Acrylamide
20   Tetrahydro-
20   Methyl
60
furfuryl     meth-
methacrylate acrylate
__________________________________________________________________________

(3) Preparation of Paint

The copolymers and homopolymer mentioned above were mixed in the proportions indicated in Table 6 with the cross-linking agent and curing catalyst added as required in the proportions similarly indicated in Table 6 and a small amount of a flow control agent further incorporated therein. The resultant mixtures were diluted with ethyl cellosolve so that their solids contents fell within the range of from 1.0 to 10.0% by weight.

(4) Application to Substrate

Polycarbonate plates 1 mm in thickness cleaned in advance were coated with the aforementioned undercoating paints by the immersion method. The undercoats thus formed were cured by heating at 130°C for 20 minutes.

B. Overcoat layer

PAC (1) Preparation of Paint

The epoxy group-containing organic silane compound and partial hydrolyzate thereof (A-1 and A-2), the polyhydric alcohols having an ethylene oxide chain (B-1 through B-4), and the vinyl polymer and copolymer having an epoxy group (C-1 and C-3) prepared by following the procedure of Examples 1-10 were mixed in the proportions indicated in Table 6, with the curing catalyst and optionally the surface active agent added thereto in the proportions also indicated in Table 6 and a small amount of a flow control agent additionally incorporated therein. The resultant mixture was diluted with ethyl cellosolve so that the solids contents fell within the range of from 20 to 50% by weight.

(2) Application to Substrate

The undercoated polycarbonate plates 1 mm in thickness were coated with the aforementioned overcoating paints by the immersion method. The overcoats thus formed were cured by heating at 130°C for one hour. The coats were tested for properties.

The results are collectively shown in Table 7.

TABLE 6
__________________________________________________________________________
Undercoat composition
Polymer                                  Overcoat Composition
Part by
Cross-linking agent
Curing Catalyst
Component (A)
Component (B)
Code
Weight
Type  Part by Weight
Type  Part by Weight
Code
Part by weight
Code
Part by
__________________________________________________________________________
weight
Example
28    U-1
100 HMMM(1)
1.4     NH4 Cl
0.19    A-1
28.6   B-1
50(50)
(10)
29    U-2
100 --    --      --    --      A-2
114.3   B-2
40(40)
(40)
30    U-3
100 A-187(2)
3.5     NH4 ClO4
0.75    A-1
85.7   B-3
20(20)
(30)
31    U-4
100 A-1100(3)
3.5     NH4 ClO4
0.80    A-1
114.3   B-4
40(40)
(40)
32    U-5
100 --    --      --    --      A-1
57.1   B-2
30(30)
(20)
33    U-6
100 --    --      --     --     A-2
57.1   B-1
40(40)
(20)
34    U-2
10 --    --      --    --      A-1
57.1   B-1
30(30)
U-4
90                                (20)
35    U-1
100 --    --      --    --      A-2
114.3   B-2
30(30)
(40)
36    U-4
100 --    --      DMAPA(4)
0.02    A-1
57.1   B-2
30(30)
(20)
37    U-5
100 Ex. 314(4)
1.5     NH4 ClO4
0.2     A-1
85.7   B-3
20(20)
(30)
Control No.
11    -- --  --    --      --    --      A-1
28.6   B-1
50(50)
(10)
12    -- --  --    --      --    --      A-2
114.3   B-2
40(40)
(40)
13    -- --  --    --      --    --      A-1
171.4   B-2
20(20)
(60)
__________________________________________________________________________
Overcoat Composition
Component (C)
Curing catalyst
Surface active agent
Code
Part by weight
Code
Part by weight
Code
Part by
__________________________________________________________________________
weight
Example
28    C-1
133.3   D-1 1.0     -- --
(40)
29    C-1
66.6   D-1 1.0     E-1
15.0
(20)
30    C-2
166.6   D-1 1.0     -- --
(50)
31    C-1
66.6   D-1 1.0     E-2
10.0
(20)
32    C-2
166.6   D-2 1.0     -- --
(50)
33    C-1
133.3   D-2 1.0     E-1
8.0
(40)                E-2
4.0
34    C-2
166.6   D-1 1.0     E-2
10.0
(50)
35    C-2
100     D-1 1.0     -- --
(30)    1∅].
36    C-1
166.6   D-1 1.0     E-1
10.0
(50)
37    C-1
166.6   D-2 1.0     -- --
(50)
Control No.
11    C-1
133.3   D-1 1.0     -- --
(40)
12    C-1
66.6   D-1 1.0     E-1
15.0
(20)
13    C-2
66.6   D-2 1.0     -- --
(20)
__________________________________________________________________________
(1) Hexamethoxymethyl melamine
(2) Glycidoxypropyl trimethoxy silane
(3) Aminopropyl triethoxy silane
(4) Glycerol polyglycidyl ether
(5) N,N--dimethylaminopropyl amine
The numerical values in parentheses are proportions by weight based on th
total of components taken as 100.

TABLE 7
______________________________________
Hot-Water
Example                resistance
Control
Non-fogging
Scratch  Adher-
Appear-
Scratch
No.    Property   resistance
ency  ance   resistance
______________________________________
Example
No fogging A        100/  Normal A
28     formed              100
Example
No fogging A        100/  "      A
29     formed              100
Example
No fogging A        100/  "      A
30     formed              100
Example
No fogging A        100/  "      A
31     formed              100
Example
No fogging A        100/  "      A
32     formed              100
Example
No fogging A        100/  "      A
33     formed              100
Example
No fogging A        100/  "      A
34     formed              100
Example
No fogging A        100/  "      A
35     formed              100
Example
No fogging A        100/  "      A
36     formed              100
Example
No fogging A        100/  "      A
37     formed              100
Control
No fogging A         0/   Film   --
11     formed              100   peeled
Control
No fogging A         0/   Film   --
12     formed              100   peeled
Control
fogging    A         0/   Film   --
13     formed              100   peeled
______________________________________

The adherency was determined by the cross-cut tape test, i.e. by inserting 11 straight cuts parallelly at fixed intervals of 1 mm each in two perpendicularly intersecting directions to form 100 cross-cut squares on the surface of the film, applying a cellophane adhesive tape to the film, lifting the tape from the film and taking count of the squares of film remaining unpeeled. The adherency was reported by this number of unpeeled squares. The hot-water resistance was determined by immersing a given test piece in boiling water for 30 minutes and subsequently examining the coat to note how the hot water had affected the coat.

EXAMPLES 38-47 and CONTROLS 14-16

PAC A. Undercoat Layer

Polymers and copolymers were prepared by following the procedure of Examples 28-37 (U-1 through U-6). By following the procedure of Examples 28-37, these polymers and copolymers and other components were mixed in the proportions indicated in Table 8 to produce undercoat paints. Thereafter, polycarbonate plates 1 mm in thickness cleaned in advance were coated with these undercoat paints by the immersion method. The coats thus formed were cured by heating at 130°C for 20 minutes.

B. Overcoat Layer

By following the procedure of Examples 1-10, the polymers and copolymers having an epoxy group (C-1 through C-3), the polyhydric alcohols having an ethylene oxide chain (B-1 through B-4) and the curing catalysts (D-1 and D-2) were mixed in the proportions indicated in Table 8, with the cross-linking agents having an epoxy group (F-1 through F-6) and the surface active agents (E-1 and E-2) optionally added thereto in the proportions also indicated in Table 8 and a small amount of a flow control agent additionally incorporated therein. The resultant mixture was diluted with ethyl cellosolve so that the solids contents fell within the range of from 20 to 50% by weight. Consequently, their was obtained overcoat paints. The undercoated polycarbonate plates 1 mm in thickness were coated with the overcoat paints by the immersion method, and the coats thus formed are cured by heating at 130°C for one hour. They were subjected to the same tests as those of Examples 28- 37. The results are collectively shown in Table 9.

TABLE 8
__________________________________________________________________________
Undercoat composition
Polymer                                  Overcoat Composition
Part by
Cross-linking agent
curing catalyst
Component (A)
Component (B)
Code
weight
Type   Part by weight
Type  Part by weight
Code
Part by weight
Code
Part by
__________________________________________________________________________
weight
Example
38   U-1
100 H.M.M.M.(1)
1.4     NH4 Cl
0.19    C-1
150(45) B-1
55(55)
39   U-2
100 --     --      --    --      C-1
110(33) B-2
67(67)
40   U-3
100 A-187(2)
3.7     NH4 ClO4
0.72    C-1
167(50) B-3
50(50)
41   U-4
100 A-1100(3)
3.5     NH4 ClO4
0.70    C-1
83(25) B-4
75(75)
42   U-5
100 --     --      --    --      C-2
183(55) B-2
45(45)
43   U-6
100 --     --      --    --      C-2
167(50) B-3
50(50)
44   U-4
100 --     --      DMAPA (4)
0.11    C-2
127(37) B-2
63(63)
(4)
45   U-6
100 --     --      TEA(5)
0.05    C-1
190(57) B-1
43(43)
46   U-2
10 --     --      --    --      C-1
167(50) B-1
50(50)
U-4
90
47   U-2
30 --     --      --    --      C-2
200(60) B-1
40(40)
U-6
70
Control
No.
14   -- --  --     --      --    --      C-1
110(33) B-2
67(67)
15   -- --  --     --      --    --      C-2
267(80) B-2
20(20)
16   -- --  --     --      --    --      C-1
167(50) B-1
50(50)
__________________________________________________________________________
Overcoat Composition
Cross-linking agent
Curing catalyst
Surface active agent
Code
Part by Weight
Code
Part by weight
Code
Part by
__________________________________________________________________________
weight
Example
38   F-1
11(11)  D-1
1.1     -- --
39   F-2
50(50)  D-1
1.5     E-1
15
40   F-3
25(25)  D-1
1.3     -- --
41   F-3
25(25)  D-1
1.3     E-2
13
42   F-4
11(11)  D-1
1.1     -- --
43   F-5
67(67)  D-1
1.7     E-1
--
44   F-5
25(25)  D-1
1.3     E-1
10
E-2
3
45   F-6
43(43)  D-2
1.4     -- --
46   -- --      D-2
1.0     -- --
47   -- --      D-1
1.0     E-2
10
Control
No.
14   F-2
50(50   D-1
1.5     E-1
15
15   -- --      D-1
1.0     -- --
16   -- --      D-1
1.0     -- --
__________________________________________________________________________
(1) Hexamethoxymethyl melamine
(2) Glycidoxy-propyl trimethoxy silane
(3) Aminopropyl triethoxy silane
(4) N,N--dimethylamino propylamine
(5) Triethanolamine
The numerical values in parentheses are weight proportions of solids base
on the total weight of the components (A) + (B) taken as 100.

TABLE 9
______________________________________
Hot-Water
Example                resistance
Control
Non-fogging
Scratch  Adher-
Appear-
Scratch
No.    property   resistance
ency  ance   resistance
______________________________________
Example
No fogging A        100/  Normal A
38     formed              100
Example
No fogging A-B      100/  "      A-B
39     formed              100
Example
No fogging A        100/  "      A
40     formed              100
Example
No fogging A-B      100/  "      A-B
41     formed              100
Example
No fogging A        100/  "      A
42     formed              100
Example
No fogging A        100/  "      A
43     formed              100
Example
No fogging A-B      100/  "      A-B
44     formed              100
Example
No fogging A        100/  "      A
45     formed              100
Example
No fogging A-B      100/  "      A-B
46     formed              100
Example
No fogging A        100/  "      A-B
47     formed              100
Control
No fogging A-B       0/   Film   --
14     formed              100   peeled
Control
Fogging    A         0/   Film   --
15     formed              100   peeled
Control
No fogging A-B       0/   Film   --
16     formed                    peeled
______________________________________

Claims

1. A non-fogging transparent coating composition free of organophosphate esters and amine aldehyde crosslinking agents, which comprises:

(A) 0 to 50 parts by weight ##STR27## of at least one compound selected from the group consisting of epoxy group-containing organic silane compounds represented by the general formula (1): ##STR28## wherein R¹ stands for an organic group having an epoxy group, R² for a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms or a vinyl group, R³ for a hydrocarbon group having 1 to 5 carbon atoms, an alkoxyalkyl group or an acyl group having 1 to 4 carbon atoms, a for an integer having the value of 1 to 3 and b 0 or for an integer having the value of 1 to 2, providing that a+b≦3 is satisfied, and partial hydrolyzates thereof,

(B) 20 to 80 parts by weight selected from triethylene glycol and a polyhydric alcohol which has an ethylene oxide chain and a molecular weight of 200 to 2000 and is capable of reacting with a component (C) as defined below or a mixture of the components (A) and (C) to form a coating film,

(C) 10 to 75 parts by weight of a polymer or copolymer containing at least 20% by weight of repeating structural units represented by the general formula (2): ##STR29## wherein, R⁴ and R⁵ independently stand for a hydrogen atom, a lower alkyl group or a carboxyl group and X stands for a side chain possessing an epoxy group, and

(D) a catalytic amount of a perchlorate curing catalyst, providing that the total of the amounts of the aforementioned components (A), (B) and (C) is 100 parts by weight.

2. A composition according to claim 1, wherein the repeating structural units represented by the general formula (2) are contained by at least 40% by weight in said polymer or copolymer (C).

3. A composition according to claim 1, which comprises 5 to 30 parts by weight of the component (A), 30 to 50 parts by weight of the component (B) and 30 to 50 parts by weight of the component (C).

4. A composition according to claim 3, wherein the component (A) accounts for a proportion within the range of from 5 to 15 parts by weight.

5. A composition according to claim 1, wherein the partial hydrolyzate of the epoxy group-containing organic silane compound represented by the general formula (1) or the mixture of not less than 70% by weight of said partial hydrolyzate with the balance to make up 100% by weight of said organic silane compound accounts for a proportion within the range of from 15 to 50 parts by weight.

6. A composition according to claim 1, wherein the epoxy group-containing organic silane compound is present in an effective amount and is glycidoxy alkyl trialkoxy silane.

7. A composition according to claim 1, wherein the polyhydric alcohol having an ethylene oxide chain is a compound represented by the general formula: ##STR30## wherein, n₁ to n_m independently stand for 0 or integers of the values of 1 to 7., at least two of which symbols represent integers of the value of at least 1, and m stands for an integer of the value of 3 to 9.

8. A composition according to claim 1, which comprises no component (A), 20 to 80 parts by weight of the component (B), 30 to 50 parts by weight of the component (C) and a catalytic amount of the component D, providing that the total of the components (B) and (C) is 100 parts by weight.

9. A compound of claim 1, wherein the polyhydric alcohol having an ethylene oxide chain is a compound represented by the general formula: ##STR31## wherein, n₁ to n_m independently stand for 0 or integers of the values of 1 to 7. at least two of which symbols represent integers of the value of at least 1, and m stands for an integer of the value of 3 to

9. 10. A composition according to claim 1, wherein the curing catalyst accounts for a proportion within the range of from 0.05 to 20 parts by weight, based on 100 parts by weight of the total of the components (A),

(B) and (C). 11. A composition according to claim 10, wherein the curing

catalyst is ammonium perchlorate. 12. A composition according to claim 8, wherein the composition further comprises an epoxy group-containing cross-linking agent in an amount of from 3 to 80 parts by weight, based on

100 parts by weight of the total of the components (B) and (C). 13. A composition according to claim 1, wherein the composition further

incorporates a surface active agent. 14. A composition according to claim 13, wherein the surface active agent is a polyoxyethylene type nonionic

surface active agent. 15. A composition according to claim 12, wherein the epoxy group-containing cross-linking agent accounts for a proportion within the range of from 5 to 60 parts by weight, based on 100 parts by weight of the total of the components (B) and (C).