CA1138590A - Polycarbonate articles coated with an adherent organopolysiloxane - Google Patents
Polycarbonate articles coated with an adherent organopolysiloxaneInfo
- Publication number
- CA1138590A CA1138590A CA000332238A CA332238A CA1138590A CA 1138590 A CA1138590 A CA 1138590A CA 000332238 A CA000332238 A CA 000332238A CA 332238 A CA332238 A CA 332238A CA 1138590 A CA1138590 A CA 1138590A
- Authority
- CA
- Canada
- Prior art keywords
- group
- article
- radical
- formula
- alkyl
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Laminated Bodies (AREA)
- Paints Or Removers (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A coated polycarbonate article comprising a polycarbonate substrate having (i) a primer layer containing a UV cured reaction product of (a) a polyfunctional acrylic ester monomer, (b) an organic silicon compound represented by the formula RCSiX4-c wherein R is an organic group containing olefinic unsaturation, X is an alkoxy, acyloxy, and aryloxy group, and c is an integer of from 1 to 3, and optionally (c) an acrylate modified polymer;
and (ii) a thermoset (silica filled) organopolysiloxane, top coat on said UV cured primer layer.
A coated polycarbonate article comprising a polycarbonate substrate having (i) a primer layer containing a UV cured reaction product of (a) a polyfunctional acrylic ester monomer, (b) an organic silicon compound represented by the formula RCSiX4-c wherein R is an organic group containing olefinic unsaturation, X is an alkoxy, acyloxy, and aryloxy group, and c is an integer of from 1 to 3, and optionally (c) an acrylate modified polymer;
and (ii) a thermoset (silica filled) organopolysiloxane, top coat on said UV cured primer layer.
Description
~ ~ 8SP 2901 This invention relates to polycarbonates. It particularly relates to polycarbonate articles having a scratch and mar resistant coating thereon. It further relates to the process of forming such coating and coating materials per se.
The use of transparent glazing material utilizing polycarbonate resin as a structural component for windows, windshields and the like are well known. While these poly-carbonate resins are easily fabricated into the desired shape and have excellent physical and chemical properties, such as being less dense than glass and having more breakage resistance than glass, their abrasion, scratch and mar resistance is relatively low.
In order to overcome this relatively low scratch and mar resistance, various coatings have been applied to these polycarbonate resins. U. S. Patents 3,451,838 dated June 24, 1969; 3,986,997 dated October 19, 1976 and 4,027,073 dated May 31, 1977 disclose a coating composition and technique for the application of organopolysiloxane coatings onto these surfaces. While these coatings have many desirable properties, e.g., they are hard, mar-resistant, scratch-resistant, and chemical solvent resistant, these organopolysiloxane coatings do not in all instances possess the desired degree of uniform adherence to and durability on the polycarbonate surfaces. There is a need for poly-carbonate articles having uniformly, tenaciously and durably adhered scratch, mar and chemical solvent resistant coatings thereon~ and it is a primary object of the present invention to provide such articles and a relatively simple and economical process for porducing these articles.
In accordance with this object, the present inven-tion as it relates to the article aspect comprises a 1~5~ 8SP 2901 polycarbonate substrate coated with a first primer layer which is overcoated with an organopolysiloxane resin of the aforementioned type. The primer layer provides a suitable substrate for a uniform, tenaciously adhering overcoat layer. The primer layer comprises the cured reaction product of a polyfunctional ester of an acrylic acid monomer and an organic silicon compound containing at least one organic group having olefinic unsaturation.
Optionally there may be included in the monomers forming the primer layer an acrylate modified polymer. Such combination of coating materials comprises one aspect of the invention.
In the method aspect of the invention, the coated primer layer is cured by exposure to UV light in the presenc of an effective photoinitiator.
The cured primer coating is then overcoated with the thermosetting organopolysiloxane of a type and in a manner generally known in the prior art earlier referred to.
These organopolysiloxanes may optionally and preferably contain therein a silica filler material so as to further improve the scratch and mar resistance of this outer layer.
The substrates of the present combination are polycarbonates such as-sold under the trade mark LEXAN
and in general comprise a plurality of units of the formula - R - C - R - O - C - O I.
B O
wherein each -R- is selected from the group consisting of phenylene, halo-substituted phenylene and alkyi substituted phenylene; and A and B are each selected from the group ~ I ~ ~ 8SP 2901 consisting of hydrogen, hydrocarbon radicals free from aliphatic unsaturation and of radicals which together with the adjoining -C- atom form a cycloalkane radical, the total number of carbon atoms in A and B being up to 12.
The aromatic carbonate polymer of this invention may be prepared by methods well known in the art and as described in U. S. Patent 3,989,672 dated November 2, 1976.
Also included herein are branched polycarbonates wherein a polyfunctional aromatic compound is reacted with the dihydric phenol and carbonate precursor to provide a thermoplastic randomly branched polycarbonate wherein the recurring units of formla I. contain branching groups.
The preferred polycarbonate resins may be derived from the reaction of bisphenol-A and phosgene. These poly-carbonates have from 10-400 recurring units of the formula:
The polycarbonate will generally have an intrinsic viscosity betwen 0.3 and 1.0, preferably from 0.40 to 0.65 as measured at 25C in methylene chloride.
The UV curable primer compositions comprises: ~i) a polyfunctional acrylic ester monomer; (ii) an organic silicon compound containing at least one organic group having olefinic unsaturation; (iii) optionally an acrylate modified polymer, and (iv) a UV photoinitiator. The poly-functional acrylic ester monomers of the present inven-tion are represented by the general formula I1 ~ 8SP 2901 r H2C = C - C - O - R III.
H n wherein n is an integer from 2 to 8, preferably from 2 to 6, and more preferably from 2 to 4, inclusive; and, Rl is an n valent saturated aliphatic hydrocarbon radical, n valent substituted saturated aliphatic hydrocarbon radical, n valent ether radical, n valent polyether radical, n valent substituted ether radical, n valent substituted polyether radical, n valent olefinically unsaturated aliphatic hydro-carbon radical, n valent substituted olefinically unsaturated aliphatic hydrocarbon radical, n valent aromatic hydrocarbon radicals, and n valent substituted aromatic hydrocarbon radicals.
By n valent saturated aliphatic hydrocarbon radicals is meant n valent radicals derived from saturated aliphatic hydrocarbons, i.e., alkanes by removal of n hydrogens there-from. Preferred n valent saturated aliphatic hydrocarbon radicals are those containing from 1 to about 20 carbon atoms. Some non-limiting examples of these preferred n valent saturated aliphatic hydrocarbon radicals include ~CH2-,
The use of transparent glazing material utilizing polycarbonate resin as a structural component for windows, windshields and the like are well known. While these poly-carbonate resins are easily fabricated into the desired shape and have excellent physical and chemical properties, such as being less dense than glass and having more breakage resistance than glass, their abrasion, scratch and mar resistance is relatively low.
In order to overcome this relatively low scratch and mar resistance, various coatings have been applied to these polycarbonate resins. U. S. Patents 3,451,838 dated June 24, 1969; 3,986,997 dated October 19, 1976 and 4,027,073 dated May 31, 1977 disclose a coating composition and technique for the application of organopolysiloxane coatings onto these surfaces. While these coatings have many desirable properties, e.g., they are hard, mar-resistant, scratch-resistant, and chemical solvent resistant, these organopolysiloxane coatings do not in all instances possess the desired degree of uniform adherence to and durability on the polycarbonate surfaces. There is a need for poly-carbonate articles having uniformly, tenaciously and durably adhered scratch, mar and chemical solvent resistant coatings thereon~ and it is a primary object of the present invention to provide such articles and a relatively simple and economical process for porducing these articles.
In accordance with this object, the present inven-tion as it relates to the article aspect comprises a 1~5~ 8SP 2901 polycarbonate substrate coated with a first primer layer which is overcoated with an organopolysiloxane resin of the aforementioned type. The primer layer provides a suitable substrate for a uniform, tenaciously adhering overcoat layer. The primer layer comprises the cured reaction product of a polyfunctional ester of an acrylic acid monomer and an organic silicon compound containing at least one organic group having olefinic unsaturation.
Optionally there may be included in the monomers forming the primer layer an acrylate modified polymer. Such combination of coating materials comprises one aspect of the invention.
In the method aspect of the invention, the coated primer layer is cured by exposure to UV light in the presenc of an effective photoinitiator.
The cured primer coating is then overcoated with the thermosetting organopolysiloxane of a type and in a manner generally known in the prior art earlier referred to.
These organopolysiloxanes may optionally and preferably contain therein a silica filler material so as to further improve the scratch and mar resistance of this outer layer.
The substrates of the present combination are polycarbonates such as-sold under the trade mark LEXAN
and in general comprise a plurality of units of the formula - R - C - R - O - C - O I.
B O
wherein each -R- is selected from the group consisting of phenylene, halo-substituted phenylene and alkyi substituted phenylene; and A and B are each selected from the group ~ I ~ ~ 8SP 2901 consisting of hydrogen, hydrocarbon radicals free from aliphatic unsaturation and of radicals which together with the adjoining -C- atom form a cycloalkane radical, the total number of carbon atoms in A and B being up to 12.
The aromatic carbonate polymer of this invention may be prepared by methods well known in the art and as described in U. S. Patent 3,989,672 dated November 2, 1976.
Also included herein are branched polycarbonates wherein a polyfunctional aromatic compound is reacted with the dihydric phenol and carbonate precursor to provide a thermoplastic randomly branched polycarbonate wherein the recurring units of formla I. contain branching groups.
The preferred polycarbonate resins may be derived from the reaction of bisphenol-A and phosgene. These poly-carbonates have from 10-400 recurring units of the formula:
The polycarbonate will generally have an intrinsic viscosity betwen 0.3 and 1.0, preferably from 0.40 to 0.65 as measured at 25C in methylene chloride.
The UV curable primer compositions comprises: ~i) a polyfunctional acrylic ester monomer; (ii) an organic silicon compound containing at least one organic group having olefinic unsaturation; (iii) optionally an acrylate modified polymer, and (iv) a UV photoinitiator. The poly-functional acrylic ester monomers of the present inven-tion are represented by the general formula I1 ~ 8SP 2901 r H2C = C - C - O - R III.
H n wherein n is an integer from 2 to 8, preferably from 2 to 6, and more preferably from 2 to 4, inclusive; and, Rl is an n valent saturated aliphatic hydrocarbon radical, n valent substituted saturated aliphatic hydrocarbon radical, n valent ether radical, n valent polyether radical, n valent substituted ether radical, n valent substituted polyether radical, n valent olefinically unsaturated aliphatic hydro-carbon radical, n valent substituted olefinically unsaturated aliphatic hydrocarbon radical, n valent aromatic hydrocarbon radicals, and n valent substituted aromatic hydrocarbon radicals.
By n valent saturated aliphatic hydrocarbon radicals is meant n valent radicals derived from saturated aliphatic hydrocarbons, i.e., alkanes by removal of n hydrogens there-from. Preferred n valent saturated aliphatic hydrocarbon radicals are those containing from 1 to about 20 carbon atoms. Some non-limiting examples of these preferred n valent saturated aliphatic hydrocarbon radicals include ~CH2-,
2 2 2 2 ~ CH2CH2CH2CH2-, -CH2CH2CHCH2CHCH -_ CH-CH2CH2-CH , -CH -C-CH2-, and the like.
l H2 These n valent saturated aliphatic hydrocarbon radicals may contain substituent groups thereon. Preferred n valent substituted saturated aliphatic hydrocarbon radicals are those containing from 1 to about 20 carbon atoms. These preferred n valent substituted saturated aliphatic hydrocarbon radicals can contain ~1 ~ ~ 8SP-2901 substituent groups such as the halogens, i.e., fluorine, chlorine, bromine and iodine, hydroxyl, -COOR2, -oR2, -CN, -COOH, -NO2, -NH2, and -NR2 wherein R2 represents alkyl radicals containing from 1 to about 6 carbon atoms. Some non-limiting examples of n valent substituted saturated aliphatic hydrocarbon radicals include --CH -C--CH --, -CH2--c--cH2--~ --CH2--CH2-f CH2 CH2 ' 2 1 1 2 2 Br Cl H OH
-CH2-CH2-CIH-CH2-, and the like.
By n valent olefinically unsaturated aliphatic hydrocarbon radicals is meant n valent radicals derived from olefinically unsaturated aliphatic hydrocarbons, i.e., alkenes by removal of n hydrogens therefrom. Preferred n valent olefinically unsaturated aliphatic hydrocarbon radicals are those containing from 2 to about 20 carbon atoms. Some non-limiting examples of these radicals I
include -CH=CH-, -CH2-CH=CH-CH2-, -CH2-CH-CH=CH-CH2-, -CH -CH-CH=CH-CH -CH2-, CH-CH=CH-CH , and the llke.
These n valent olefinically unsaturated aliphatic hydrocarbon radicals may contain substituent groups thereon. Preferred n valent substituted olefinically unsaturated aliphatic hydrocarbon radicals are those containing from 2 to about 20 carbon atoms~
These radicals can contain substituent groups such as the halogens, -COOR , -OR , -CN, -COOH, -NO2, -NH2, and -NR wherein R is as defined above. Some non-limiting examples of n valent substituted olefinically unsaturated aliphatic hydrocarbon radicals include H OH
_CH2_fH_CH=cH_cH2_, --CH2-CH=CH-C-CH-C~2- ~ ~CH-C~=CH-C-Cl ~H2 H
` 8SP-2901 Cl oOR2 -C-CH2-CH=CH-CH-CH2, and the like.
H
By n valent ether radicals is meant n valent radicals derived from ethers by removal of n hydrogens therefrom. Preferred n valent ether radicals are those containing from 2 to about 20 carbon atoms. Some non-limiting examples of these n valent ether radicals include -CH2-O-CH2-, ~ CH-CH2-O-CH2-CH ~ , 2 2 2 CHCH2-, -CH2CHCH2-O-CH -CH
These n valent ether radicals may contains substituent groups thereon. Preferred n valent substituted ether radicals are those 1~ containing from 2 to about 20 carbon atoms. These radicals can contain substituent groups such as the halogens, -COOR2, _oR2 -CN, -COOH, -NO2, -NH2, and -NR2 wherein R is as defined above.
Some non-limiting examples of n valent substituted ether radicals Br OH
2 2 2 CH2-CH2-, ~ CH-CH-CH -O-CH CH
CH-CH-CH -O-CH -CH ~ , -CH -CH-CH -O-CH -CHCH -, and the like By n valent polyether radicals is meant n valent radicals derived from polyethers, which polyethers are represented by the general formula ~R3O~X wherein x is an integer from 2 to about 5 and R3 is a lower alkyl, by removal of n hydrogens therefrom.
Preferred n valent polyether radicals are those containing from
l H2 These n valent saturated aliphatic hydrocarbon radicals may contain substituent groups thereon. Preferred n valent substituted saturated aliphatic hydrocarbon radicals are those containing from 1 to about 20 carbon atoms. These preferred n valent substituted saturated aliphatic hydrocarbon radicals can contain ~1 ~ ~ 8SP-2901 substituent groups such as the halogens, i.e., fluorine, chlorine, bromine and iodine, hydroxyl, -COOR2, -oR2, -CN, -COOH, -NO2, -NH2, and -NR2 wherein R2 represents alkyl radicals containing from 1 to about 6 carbon atoms. Some non-limiting examples of n valent substituted saturated aliphatic hydrocarbon radicals include --CH -C--CH --, -CH2--c--cH2--~ --CH2--CH2-f CH2 CH2 ' 2 1 1 2 2 Br Cl H OH
-CH2-CH2-CIH-CH2-, and the like.
By n valent olefinically unsaturated aliphatic hydrocarbon radicals is meant n valent radicals derived from olefinically unsaturated aliphatic hydrocarbons, i.e., alkenes by removal of n hydrogens therefrom. Preferred n valent olefinically unsaturated aliphatic hydrocarbon radicals are those containing from 2 to about 20 carbon atoms. Some non-limiting examples of these radicals I
include -CH=CH-, -CH2-CH=CH-CH2-, -CH2-CH-CH=CH-CH2-, -CH -CH-CH=CH-CH -CH2-, CH-CH=CH-CH , and the llke.
These n valent olefinically unsaturated aliphatic hydrocarbon radicals may contain substituent groups thereon. Preferred n valent substituted olefinically unsaturated aliphatic hydrocarbon radicals are those containing from 2 to about 20 carbon atoms~
These radicals can contain substituent groups such as the halogens, -COOR , -OR , -CN, -COOH, -NO2, -NH2, and -NR wherein R is as defined above. Some non-limiting examples of n valent substituted olefinically unsaturated aliphatic hydrocarbon radicals include H OH
_CH2_fH_CH=cH_cH2_, --CH2-CH=CH-C-CH-C~2- ~ ~CH-C~=CH-C-Cl ~H2 H
` 8SP-2901 Cl oOR2 -C-CH2-CH=CH-CH-CH2, and the like.
H
By n valent ether radicals is meant n valent radicals derived from ethers by removal of n hydrogens therefrom. Preferred n valent ether radicals are those containing from 2 to about 20 carbon atoms. Some non-limiting examples of these n valent ether radicals include -CH2-O-CH2-, ~ CH-CH2-O-CH2-CH ~ , 2 2 2 CHCH2-, -CH2CHCH2-O-CH -CH
These n valent ether radicals may contains substituent groups thereon. Preferred n valent substituted ether radicals are those 1~ containing from 2 to about 20 carbon atoms. These radicals can contain substituent groups such as the halogens, -COOR2, _oR2 -CN, -COOH, -NO2, -NH2, and -NR2 wherein R is as defined above.
Some non-limiting examples of n valent substituted ether radicals Br OH
2 2 2 CH2-CH2-, ~ CH-CH-CH -O-CH CH
CH-CH-CH -O-CH -CH ~ , -CH -CH-CH -O-CH -CHCH -, and the like By n valent polyether radicals is meant n valent radicals derived from polyethers, which polyethers are represented by the general formula ~R3O~X wherein x is an integer from 2 to about 5 and R3 is a lower alkyl, by removal of n hydrogens therefrom.
Preferred n valent polyether radicals are those containing from
3 to about 20 carbon atoms. Some non-limiting examples of these n valent polyether radicals include -CH2-CH2-O-CH2CH2-O-CH2CH2-, C C 2 2 2 C 2C ~ ~ CH2 O C 2 CH2 t CH2 C O C 2 C 2 -O-CH2-CH2~, and the like.
~1 These n valent polyether radicals may contain substituent groups such as halogens, hydroxyl, -COOR2, CN, -COOH, -NO2, -NH2 and -NR thereon. Some non-limiting examples of these n valent substituted polyether radicals include Cl Br -CH-CH2-0-CH2CH2-0-CH2CH2 0 CH2CH2, By n valent aromatic hydrocarbon radicals is meant n valent radicals derived from aromatic hydrocarbons, e.g., benzene, naphthalene and anthracene, by removal of n hydrogens therefrom.
Preferred n valent aromatic hydrocarbon radicals are those con-taining from 6 to 18 carbon atoms. Some non-limiting examples of these preferred n valent saturated aliphatic hydrocarbon radicals include and the like. These n valent aromatic hydrocarbon radicals may further contain substituent groups such as halogens, lower alkyls, hydroxyl, -COOR2, -COOH, -NH2, -NO2, -oR2, and -CN thereon.
It is to be understood that where substituent groups are present, they should be such that they do not unduly hinder or interfere with the photocure of the polyfunctional acrylic monomers.
In the practice of the present invention, it is preferred that Rl be a n valent saturated aliphatic hydrocarbon radical, a n valent ether radical, or a n valent pclyether radical.
,~ _ ~138S90 ``
~ore particularly, the difunctional acrylic acid ester ' monomers, or diacrylates, are represented by formula III wherein n is 2; the trifunctional acrylic acid ester monomers, or tri-acrylates, are represented by formula III wherein n is 3; and the tetra-functional acrylic acid ester monomers, or tetraacrylates, are represented by formula III wherein n is 4.
.lustrative of suitable polyfunctional acrylate ester monomers of formula III are those listed below in TABLE I.
TABLE I
1~ Diacrylates of Formula III
1. CH2=CHCOO-CH2-OOCCH=CH2 2. CH2=CHCOO-CH2-CH2-OOCCH=CH2 3. CH2=CHCOO-CH2-CHOHCH2-OOCCH=CH2
~1 These n valent polyether radicals may contain substituent groups such as halogens, hydroxyl, -COOR2, CN, -COOH, -NO2, -NH2 and -NR thereon. Some non-limiting examples of these n valent substituted polyether radicals include Cl Br -CH-CH2-0-CH2CH2-0-CH2CH2 0 CH2CH2, By n valent aromatic hydrocarbon radicals is meant n valent radicals derived from aromatic hydrocarbons, e.g., benzene, naphthalene and anthracene, by removal of n hydrogens therefrom.
Preferred n valent aromatic hydrocarbon radicals are those con-taining from 6 to 18 carbon atoms. Some non-limiting examples of these preferred n valent saturated aliphatic hydrocarbon radicals include and the like. These n valent aromatic hydrocarbon radicals may further contain substituent groups such as halogens, lower alkyls, hydroxyl, -COOR2, -COOH, -NH2, -NO2, -oR2, and -CN thereon.
It is to be understood that where substituent groups are present, they should be such that they do not unduly hinder or interfere with the photocure of the polyfunctional acrylic monomers.
In the practice of the present invention, it is preferred that Rl be a n valent saturated aliphatic hydrocarbon radical, a n valent ether radical, or a n valent pclyether radical.
,~ _ ~138S90 ``
~ore particularly, the difunctional acrylic acid ester ' monomers, or diacrylates, are represented by formula III wherein n is 2; the trifunctional acrylic acid ester monomers, or tri-acrylates, are represented by formula III wherein n is 3; and the tetra-functional acrylic acid ester monomers, or tetraacrylates, are represented by formula III wherein n is 4.
.lustrative of suitable polyfunctional acrylate ester monomers of formula III are those listed below in TABLE I.
TABLE I
1~ Diacrylates of Formula III
1. CH2=CHCOO-CH2-OOCCH=CH2 2. CH2=CHCOO-CH2-CH2-OOCCH=CH2 3. CH2=CHCOO-CH2-CHOHCH2-OOCCH=CH2
4. CH2=CHCOO-(CH2)6-OOCCH=CH2
5. CH2=CHCOO-CH2-CH2-fH-CH3
6. CH2=CHCOO-CH2CH2OCH2CH2-OOCCH=CH2
7. CH2=CHCOO-CH2CH2OCH2CH2OCH2CH2OCH2CH2-OOCCH=CH2 fH3
8. CH2=CHCO0-CH2-C-OOCCH=CH2 CH2Br g. CH2=CHCOO-CH2-f-OOCCH-CH2 10. CH2-CHCOO-CH2-C-OOCCH=CH2 fH2H
11. CH2-CHCOO-CH2-f-OOCCH=CH2 C~20X
il38590 fH20~
12. CH2=CHCOO-CH2-f-OOCCH=CH2 - CH2Br 13. CH2=CHCOO-CH2-CH=CH-CH2-CH2-OOCCH=CH2 14. CR2=CHCOO-CH2-CH=CH-fH-OOCH=CH2 fH20H
15. CH2--CHCOO-CH2-f-CH2OOCCH=CH2 CH2Cl _ _ 5 16._ CH2-CHCOO-CH2-CH - CH2-OOCCH=CH2 17. CH2=CHCOO ~ OOCCH=CH2 18. CH2=CHCOO ~ OOCCH=CH2 Br 19. CH2=CHCOO~OOCCH=CH2 OH
20. CH2=CHCOO ~ OOCCH=CH2 1021. CH2=CHCOO-CHCH2CH2-OOCCH=CH2 ~3 22. CH2=CHCOQ-CH2CH2CH CH2-OOCCH=CH2 . Triacrylates_of Formula III
23. CH2=cHcoo-fH2 C82=CHCOO-CH2-f-CH2-CH3 CH2=CHCOO-CH~
1 1 ~ ~ 8SP-2901 24.fH2OH
CH2=CHCOO-CH2-C-C~I2-OOCCH=CH2 1H2-OOCCH=CH2 OOCCH=CH2 25. CH2=CHCOO~ --OOCCH=CH2 Tetraacrylates of Formula III
26.CH2=CHCOO-IH2 CH2=CHCOO-CH2-C--CH2-OOCCH=CH2 27. CH2=CHCOO-CH2 CH-CH CH2-OOCCH=CH2 CH2=CHOO-CH2CH2-OOCCH=CH2 ~H
28. CH2=CHCOO-CH2fHCH-CH2fH-OOCCH=CH2 CH2=cHcoo-cH2 CH2-OOCCH-CH2 These polyacrylate esters and their production are well known to those skilled in the art. One method of producing the di-, tri-, and tetraacrylate esters involves reacting acrylic acid with a di-, tri-, or tetrahydroxyl compound to produce thediester, triester or tetraester. Thus, for example, acrylic acid can be reacted with ethylene glycol to produce ethylene glycol diacrylate (compound 2 in Table I).
It is to be understood that the instant primer compositions may contain only one polyfunctional acrylic acid ester msnomer or a mixture of two or more, preferably two, differen~ monomers. In certain instances, it is preferred that the primer compositions contain mixtures of two or more, preferably two, different monomers.
The organic silicon compounds of the present invention are represented by the formula ~ 1 ~ ~ 8SP-2901 R2CSiX4_c IV.
wherein X independently represents an alkoxy, acyloxy and aryloxy group, R2 represents an organic group containing olefinic unsatura-tion, and c is an integer from 1 to 3.
Preferred alkoxy groups are those containing from 1 to about 10 carbon atoms. Exemplary preferred alkoxy groups include methoxy, propoxy, butoxy, pentoxy, heptoxy, and the like. Preferred acyloxy groups are those containing from 2 to about 10 carbon atoms. Exemplary preferred alkoxy groups include acetoxy, propionoxy, butyroxy, pentanoxy, hexanoxy and the like. The preferred aryloxy group is phenoxy.
R2 represents an organic group containing olefinic unsatur-ation such that the compound of formula IV will co-react with the polyfunctional acrylic acid ester monomer and with ~Y acrylate modified polymer upon exposure to W light and in the presence of a W photoinitiator to form a thermoset reaction product which im-proves the adhesion of an organopolysiloxane to the polycarbonate sub-strate. R is preferably selected from the group consisting Of-acry-loxy-alkyls and methacryloxy alkyls represented by the general formula Y p CH2 = C - C - O - R3 V.
wherein R3 is an alkylene group~ preferably containing 1 to about 12 carbon atoms, and more preferably containing from 2 to 6 carbon atoms, and Y is hydrogen or methyl; and an alkyl maleamic acid represented by the formula ¦¦ H
HC ~ ~ - R3 - VI.
ll HC ~ ~ H
~ SP 2901 wherein R is as defined above.
The primer compositions of the present invention may contain only one organic silicon compound of formula IV
or they may contain mixtures of two or more, but preferably two, different compounds of formula IV. Thus, for example, the primer compositions may contain two different compounds of formula V, two different compounds of formula VI, or one compound of formula V and one compound of formula VI.
The third optional component of the coating composi-tions of the present invention is an acrylate modified poly-.eric resin. The acrylate modified polymeric resins are convetnional polymer types whose structure and preparation are known in the art. These acrylate modified polymers have UV reactive acrylate groups incorporated into the polymer.
Generally, these acrylate modified polymers are represented by the general formula _ Polymer ¦ Acrylate VII.
wherein z is an integer of from 1 to about 5 and Polymer is a z valent polymeric material, and Acrylate is a mono-, di-, tri- or tetraacrylate group. Thus, a difunctional polymer, (z is 2) would have a structure represented by the formula Acrylate - Polymer - Acrylate, VIII.
a trifunctional polymer, (z is 3) would have the structure represented by the formula Acrylate - Polymer - Acrylate, Acrylate and so forth.
Thus, a polymer having monofunctional acrylates attached thereto would be represented by the formula Polymer - O - C - CH - CH2l IX.
11:~8590 wherein Polymer and z are as defined above. A polymer having polyfunctional acrylates attached thereto would be represented by the formula O
Polymer-t~-Rl ~ O _ C - CH = CH~ n \) Z X.
wherein Polymer, Rl, n and z are as defined above.
Polymers having both monofunctional and poly-functional acrylate groups attached thereto are also useful in the practice of the preSent invention. These types of acrylate modified polymers are represented by the structural formula C H2C=CH-C-O~ R -Polymer ~-R - L C~CH=C~ n 1) P
wherein Polymer, R , and n are defined above, and m and p are integers having a value of from 1 to 3, provided that the sum of m + p does not exceed 5.
Exemplary typical acrylate modified polymers, wherein the acrylate is a monoacrylate, are acrylate poly-esters represented by the formula O O O O
2 ( 2)6 r C tcH2 4 c 0-(cH2)~ O-C-CH=CH
acrylate epoxies represented by the formula O OH CH OH O
20CH2=CH-C-O ECH2 CH CH2 ~3_1 3 ~nlCH2-1H-CH2--C-CH=CH2 and acrylate urethanes represented by the formula O O O O
CH2=CH-C-OCL2CH2 [~-O-C-NH~ 3-C-O-CH2CH~l n,O-C-CH=CH2 where n' is a number such that the molecular weight of the polymer is in the approximate range of about 400 to about several thousand, although this range is not at all critical.
Preferred acrylate modified polymers are the acrylate epoxies as described in U.S. 3,586,526 issued June 22, 1971, acrylate urethanes as described in U.S.
3,297,745, issued Jan. 10, 1967, acrylate alkyd urethanes as described in U.S. 3,673,140 issued June 27, 1972, acrylate polycaprolactones as described in U.S. 3,700,643 issued Jan. 23, 1973, acrylate polyesters, and acrylate polyethers as described in U.S. 3,380,831 issued April 30, 1968.
Generally, the primer compositions of the present invention contain a ratio, by weight, of acrylate poly-functional acrylic acid ester monomer to acrylate modified polymer of up to about 1:10; preferably the ration of these components will be in the range of about 1:2 to about 2:1.
The amount of polyfunctional acrylic acid ester monomer plus acrylate modified polymer present in the primer composi-tions is generally from about 10 to about 80 weight percent, preferably from about 20 to about 40 weight percent, while the amount of organic silicon compound present is generally from about 20 to about 90 weight percent, preferably from about 40 to about 80 weight percent.
The photocurable primer compositions also contain a photoinitiating amount of a suitable photoinitiator, i.e.
an amount effective to effect the photocure of the coating composition. Generally, this amount is from abcut 0.01% to about 10% by weight, preferably from about 0.1% to about 5% by weight of the photocurable primer composition, exclu-sive of any solvent present. These additives and the cure thereof are generally well known in the art. Some non-limiting examples of these UV radiation photosensitizers 1 ~ ~ ~ 8SP 2901 include ketones, such as benzophenone, acetophenone, benzil, benzyl methyl ketone; benzoins and substituted benzoins such as benzoin methyl ether, ~ -hydroxymethyl benzoin iso-propyl ether; halogen containing compounds such as ~ -bromo-acetophenone, p-bromoacetophenone, ~ -chloromethylnaph-thalene; sulfur compounds such as aromatic disulfides;
and other photosensitizers such as azides, thioketones, or mixture of synergistic mixtures thereof; the diaryl peroxides;
the hydroperoxides; the peracids and peresters; the azo compounds, or any other known free radical initiator, such as di-t-butyl peroxide, benzoyl peroxide, 2,4-dichloro-benzoyl peroxide, t-butyl hydroperoxide, peroxyacetic acid, perioxybenzoic acid, t-butyl peroxypivalate, t-butyl per-acetate, azobisisobutyronitrile and the like.
The primer compositions of the present invention may contain a resorcinol monobenzoate. The resorcinol mono-benzoate is preferably unsubstituted, although a lower alkyl substituted resorcinol monobenzoate may also be used.
Generally, the resorcinol monobenzoate is present in an amount of from about 1 to about 10 percent by weight. Although the resorcinol monobenzoate or substituted resorcinol mono-benzoate or substituted resorcinol monobenzoate is generally not believed to be directly involved in the reaction between the polyfunctional acrylic acid ester monomer and the silicon containing compound, and, therefore, is not believed to be generally directly incorporated into the cured cross-linked polymer structure formed by the coreaction of the polyfunctional acrylic acid ester monomer and the silicon containing compound, it nevertheless functions in a manner to promote and increase the durability of adhesion of the organopolysiloxane top coat to the primary layer, especially upon exposure of the coated polycarbonate article 1 ~ _ 1 ~ ~ ~ 8SP 2901 to light. More specifically, during the cure of the primer layer by the action of ultraviolet light, the resorcinol monobenzoate present in said layer is converted by the ultra-violet radiation to a dihydroxybenxophenone. This dihydroxy-benzophenone then acts, in the cured primer, as an ultra-violet light absorber and promotes the durability and adhesion of the organopolysiloxane top coat to the primer layer.
The primer compositions of the instant invention may also optionally contain various flatting agents, surface active agents and thioxtropic agents. All of these additive and the use thereof are well known in the art and do not require extensive discussions. Therefore, only a limited number will be referred to, it being understood that any compounds possessing the ability to function in such a manner, i.e., as a flatting agent, surface active agent and the like, can be used so long as they do not deleter-iously affect the photocuring of the primer compositions and do not adversely affect the non-opaque character of the coated polycarbonate article where it is desirable that this be retained.
The various surface-active agents, including anionic, cationic and nonionic surface-active agents are described in Kirk-Othmer Encyclopedia of Chemical Technology, Vol. 13, Interscience Publishers, New York, 1969, pp. 507-593, and Encyclopedia of Polymer Science and Technology, Vol. 13, Interscience Publishers, New York, 1960, pp. 477-486.
In the practice of the present in~ention, the photo-curable primer compositions are first compounded by adding together the polyfunctional acrylic acid ester monomer, thP organo silicon compound, the UV photoinitiator, and - 16 ~
~ SP 2901 where indicated one or more of the other aforementioned additives. Additionally, if so desired to reduce the vis-cosity of the primer formulation or to aid in stabilizing the organo silicon compounds, an organic solvent may be incorporated into the formulation. Generally, the amount of solvent, if any, should be such that evaporation of the solvent occurs before any deleterious effect on the substrate due to the aggressiveness (in the chemical etching sense) of the primer compositions develops. The various components are thoroughly mixed so as to form a generally homogeneous primer composition. A thin, uniform film of the primer solution is then applied onto the polycarbonate surface by any of the known means such as dipping, spraying, roll-coating and the like. Generally, the primer composition is applied in an amount sufficient to provide a cured film of from about 0.005 mil to about 0.5 mil, preferably from about 0.05 mil to about 0.2 mil thick. The primer film is then cured in an inert, e.g., nitrogen, atomosphere, by UV irradiation which can have a wavelength of from 1849A. to 4000A. The lamp systems used to generate such radiation can consist of ultraviolet lamps which can consist of discharge lamps, as for example, xenon, metallic halide, metallic arc, such as low or high pressure mercury vapor discharge lamps, etc., having generating pressure of from as low as a few milli- torr up to about 10 atmospheres, can be employed. After UV curing, there is present on the surface of the polycarbonate a non-opaque primer which is adhered to the polycarbonate. This UV cured primer is believed to be the polymerizable product of the aforedescribed (i) polyfunctional acrylic acid ester monomer or mixtures of polyfunctional acrylic acid ester monomers; (ii) organic silicon compound or mixtures of organic silicon ~ ~ ~ ~ 8SP 2901 compounds; and when employed, (iii) the crylate modified polymers or mixtures of acrylate modified polymers. The ultraviolet radiation cured primer may further contain the photoreaction products of the resorcinol or substituted mono-benzoate, or mixtures thereof, where employed in the afore-described manner. These products consist mainly of dihydroxybenzophenone, or in the case of alkyl substituted resorcinol monobenzoate, alkyl substituted dihydroxybenzo-phenone. The resulting cured primer coat is a thermoset, hard, non-tacky material which is tenaciously adhered to the polycarbonate substrate.
The organopolysiloxane compound which is useful in the formulation of the silicone top coat that is applied to the foregoing cured primer composition is generally a silane selected from silanes of the formula R4aSi(OR )4-a XI.
and the silanes of the formula R4bSi(OCOR )4 b XII.
and partial hydrolysis and condesation products thereof where R3 is selected from monovalent hydrocarbon radicals and halogenated monovalent hydrocarbon radicals and is preferably an alkyl radical of 1 to about 8 carbon atoms or phenyl radicals, where a is a zero or 1, and R4 and R5 may be monovalent hydrocarbon radicals and halogenated mono-valent hydrocarbon radicals but are preferably alkyl radicals of l to about 8 carbon atoms and phenyl radicals, where b may vary from 0 to 2. The above silanes or partial hydrolysis and condensation products of such silanes are applied in anywhere from about 10% to about 100% solids, wherein the solvent is water or an organic solvent, pre-ferably alkanol. Such silane top coat composition is then allowed to cure at a temperature anywhere from 20 to ~ 1 ~ ~ 8SP 2901 to 130C. The silicone top coat composition has to be cured preferably at an elevated temperature to effect the proper cure, but the temperature has to be below the glass transi-tion temperature of the polycarbonate.
Such alkoxylated and acyloxy functional silanes are well known materials to silicone manufacturers and are easily obrainable. Thus, for instance, these silanes are noted in U.S. Patents 3,720,699 issued March 13, 1973;
3,650,808 issued March 21, 1972 and 3,701,7~3 issued October 31, 1972.
These are not the only silicone top coats that may be utilized with the primer composition of the instant case. Less preferred silicone top coats which can be hydro-lyzed or partially dissolved in a solvent in the foregoing solids content of 10 to 100% solids are, for instance, silicone resins composed of trifunctional and difunctional units, silicone resins composed of trifunctional units, difunctional units and tetrafunctional units where the organo substituent groups in the trifunctional units may be selected from alkyl radicals of 1 to 8 carbon atoms and are preferably, methyl, phenyl and vinyl; and wherein the organo substituent groups in the difunctional siloxy units may be selected again from alkyl radicals of 1 to 8 carbon atoms, vinyl radicals and phenyl radicals. Such silicon resins usually have an organic to silicon atom ratio of 1:1 to 1.9:1; may have a silanol content that varies anywhere from 4 to 10 weight percent and optionally may have an alkoxy content that varies from 2 to 4~. The prepara-tion of such silicone resins which may be utilized at top coats in the invention of the instant case are, for instance, to be found in the patents of Duane F. Merrill, i.e.
~ 1 ~ ~ 8SP 2901 U.S. Patents 3,375,223 issued March 28, 1968; 3,435,001 issued Mar. 25, 1969; 3,450,672 issued Jun~ 17, 1969;
3,790,527 issued Feb. 5, 1974; 3,832,319 issued Aug. 27, 1974; 3,865,766 issued Feb. 11, 1975; 3,887,~14 issued Jan. 3, 1975 and 3,925,276 issued Dec. 9, 1975. However, it must be pointed out that such silicone resins are not the preferred ilicone top coat materials of the invention of the instant case. The foregoing alkoxy silanes of Formula XI and the foregoing acyloxy functional silanes of Formula XII are the most preferred. Other well known silicone top coat compositions for metals, plastics, ceramics and glass may be utilized with the primer composition of the instant case. As stated previously, the foregoing alkoxy functional silanes of Formula XI and the acyloxy functional silanes of Formula XII are preferred.
When the curable organopolysiloxane composition applied as a top coat is silica filled, the silica will normally be an aqueous hydrosol, ie a colloidal silica.
Aqueous colloidal silica dispersons generally have a particle size in the range of 5 to 150 millimicrons in diameter. These silica dispersions are prepared by methods well-known in the art and are commercially available. It is preferred to use colloidal silica having a particle size in the range of 10 to 30 millimicrons in diameter in order to obtain dispersions having a greater stability and to provide top coatings having superior optical properties.
The silica filled organopolysiloxane top coat compositions may be prepared by adding trialkoxysilanes to colloidal silica hydrosol and adjusting the pH to a range of 3.0 to 6.0 by the addition of acid to prevent gellation. The suitable acids include both il38S90 organic and inorganic acids such as hydrochloric, choroacetic, acetic, citric, benzoic, formic, propionic, maleic, oxalic, glycolic and the like. The acid may be added to either the silance or the silica hydrosol before the two components are mixed. In this medium the silanes of formulae XI and XII will of course be hydrolysed to form silanes of the formula:
Ra Si(OH)4 a XIII.
and partial siloxane condensation products thereof.
Desirably a in formula XIII will have a value 1. Also desirably, R4 is selected from lower alkyl of 1-3 carbons vinyl; 3,3,3,-trifluoropropyl, gamma-glycidoxypropyl and gamma-methacryloxypropyl, with at least 70% of the R4 radicals being methyl. Most preferably R is methyl.
The most suitable trialkoxysilanes are those containing methoxy, ethoxy, isoporpoxy and t-butoxy groups. The hydrolysis of the preferred silanes, ie those of formula XI wherein a is 1, will generate the corresponding trisilanols and alcohol. Depending upon the percent solids desired in the final coating composition, additional alcohol, water, or a water-miscible solvent can be added. Suitable alcohols are the lower aliphatci alcohols such as methanol, ethanol, isopropanol, t-butanol, and mi~tures thereof.
Generally, the solvent system should contain from about 20 to about 75 weight percent alcohol to ensure solubility of the siloxanol formed by the condesnation of the silanol.
~f desired, a minor amount of an additional water-miscible polar solvent such as acetone, butyl Cellosolve ~ , and the like can be added to the water-alcohol solvent system.
Generally, sufficient alcohol or water alcohol solvent is added to give a composition containing from about 10 to 50 percent by weight of solids, said solids generally tl~S~ 8SP 2901 comprising from about 10 to about 70 percent by weight of colloidal silica and from about 30 to about 90 percent by weight of the partial condensate of the silanol. The composition is allowed to age for a short period of time to ensure formation of the partial condensat of the silanol, i.e., the siloxanol. This condensation occurs upon generation of the silanol in the acidic aqueous medium through the hydroxyl substituents to form Si-O-Si bonding. The condensation is not complete, resulting in a siloxane having an appreciable quantity of silicon-bonded hydroxyl group.
The foregoing top coat composition whether or not silica filled is then applied onto the primed polycaronate by any of the commonly known methods such as dipping, spraying, flow-coating and the like. After the top coat composition is applied to the primed polycarbonate, the polycarbonate is air dried if necessary to evaporate the volatile solvents from the top coat composition. There-after, heat is applied to cure the top coat. During curing, the residual hydroxyls of the siloxane condense to give a silsesquioxane, R SiO3/2. The result is a silica filled cross-linked organopolysiloxane top coat which is tena-ciously adhered to the substrate and is highly resistant to scratching, abrasion, chemical solvents, and marring.
Generally, the silica filled top coat contains from about 10 to about 70 weight percent silica and from about 30 to about 90 weight percent of the organopolysiloxane present as the silsesquioxane RSio3/2.
The thickness of the top-coat generally is dependent upon such factors as upon the method of application and the weight percent solids present in silica filled further curable organopolysiloxane top coat composition. In general, the higher the percent solids, and the longer the application i~ ~ ~ 8SP 2901 time, the greater the thickness of the top coat. Thicker coats can in general be prepared when using the silica filled materials. It is preferred that the cured top coat have a thickness of from about 0.1 to about 0.5 mils, more preferably from 0.15 to about 0.4 mils, and most preferably from about 0.2 to about 0.25 mils.
Another embodiment of the present invention is a process of producing a mar, abrasion, scratch and chemical resistant polcarbonate article. The process comprises the steps of: (i) applying onto the polycarbonate an ultraviolet light curable primer composition containing (a) at least one polyfunctional acrylic acid ester monomer represented by formula III, (b) an organo silicon compound containing at least one olefinically unsaturated organic group, said compound being represented by formula IV, (c) and optionally a further reactive acrylate modified polymer; (d) an ultra-violet light photoinitiator, and preferably te) a resorcinol monobenzoate; (ii) applying ultraviolet light of sufficient strength and for a period of time effective to cure said primer composition and form a cured primer layer on said polucarbonate substrate; then (iii) applying a silica filled further curable organopolysiloxane top coat composi-tion onto said cured primer layer, (iv) evaporating off the volatile solvents present in the top coat composition;
and tv3 curing the top coating by the application of heat thereto to form a silica filled thermoset organopolysiloxane, i.e., a silsequioxane.
In order to more fully and clearly illustrate the present invention, the following specific examples are presented. It is intended that the examples be considered as illustrative rather than limiting the invention disclosed and claimed herein.
~ 1 ~ 5 ~ 8SP 2901 An aromatic polycarbonate is prepared by reacting 2,2-bis(4-hydroxyphenyl) propane and phosgene in the presence of an acid acceptor and a molecular weight regulator and having an intrinsic viscosity of 0.57. The product is then fed to an extruder, which extruder is operated at about 265C and the extrudate is comminuted into pellets.
The pellets are then injection molded at about 315C into test panels of about 4 in. by 4 in. by about 1/8 in. thick. The test panels are subjected to an abrasion test.
The abrasion test is one wherein test panels having a 1/4 inch diameter hole cut in the center are sub-jected to a Taber Abraser. The Taber Abraser is equipped with CS-lOF wheels which are resurfaced every 200 cycles by abrading for 25 cycles on a S-ll refacing disc. The weights are used in combination with the CS-lOF wheels are 500 gm. weights. Initial measurements of ~ Haze are made at four places around the future wear track of the sample using a Gardner Hazemeter. The sample is abraded for 500 cycles, cleaned with isoporpanol, and the ~ Haze is remeasured at the same four places. The four differences in % Haze are calculated and averaged to give the Haze. The results are set forth in Table II.
~38S~ 8SP 2901 A primer composition is prepared by blending 50 gms. of 1,6-hexanediol diacrylate, 50 gms. of a 50~
ethanolic solution of N- L- (triethoxysilyl) propy~ maleamic acid which has been aged, i.e., allowed to stand for an extended period fo time, 1.5 gms. of ~ , ~ -diethyoxyaceto-phenone, 7.5 gms. of resorcinol monobenzoate, and 7.5 gms. of resorcinol monobenzoate, and 750 gms. of isobutanol.
To 250 gms. of this solution are added 250 gms. of isobutanol.
A thin film of this primer composition is applied to poly-~
carbonate test panels prepared in accordance with Example 1.
The film is cured by passing the polycarbonate panels through a combination Linde photocuring apparatus (this consists of a variable speed conveyor running through a chamber containing germicidal type mercury vapor lamps which emit light mainly at 2537A, 3150A, and 3605A) wherein the nitrogen pressure is 25 psi nitrogen and the speed of the conveyor is 30 ft/min. The film is tack free and cured after this treatment.
~38590 :
A primer composition is prepared by blending 250 gms. of 1,6-hexanediol diacrylate, 125 gms. of an aged 50% ethanolic solu-tion of N-/3-(triethoxysilyl) propyl7 maleamic acid, 62 gms. of pentaerythitol-triacrylate, 7.5 gms. of ~, ~ -diethoxy-acetophen-one, 1.2 gms. of resorcinol monobenzoate and 600 gms. of isobutanol. 250 gms. of the resulting solution is diluted in 1900 gms. of isobutanol. A thin f ilm of this primer composition is applied to polycarbonate test panels prepared in accordance with Example 1. The film is cured by priming through a Linde photo-curing apparatus as set forth in Example 2.
- ~ primer composition is prepared by blending 250 gms. of 1,6-hexanediol diacrylate, 125 gms. of y-methacryloxy-propyl trimeth-oxysilane, 62 gms. of trimethylolpropane triacrylate, 7.5 gms. of ~ , ~-diethoxyacetophenone, 36.5 gms. of resorcinol monobenzoate, and 600 gms. of isobutanol. To 250 gms. of the resulting solution are added 1900 gms. of isobutanol.
EX~PLE 5 The primed polycarbonate panels prepared in accordance with Example 2 are coated with an organopolysiloxane coating composition containing a further curable organopolysiloxane and an alkanol solvent, the further curable organopolysiloxane being a precured hydrolysis and partial condensation product of a methyltrialkoxy silane, e.g., methyltrimethoxysilane. ~fter the organopolysiloxane coating composition is applied to the primed surface of the poly-carbonate test panels, the coated panels are air dried for 30 minutes to evaporate the solvent, followed by a one hour bake at 250F t~ cure the organopolysiloxane. The coated panels are then ~138S~ 8SP 2901 subjected to the abrasion test as in Example 1 and the results are set forth in Table II.
The primed polycarbonate panels prepared in accor-dance with Example 3 are coated with an organopolysiloxane coating composition containing a further curable organopoly-siloxane being a precured hydrolysis and partial condensation product of a methyltrialkoxysilane, e.g., methyltrimethoxy-silane. After the organopolysiloxane coating composition is applied to the primed surface of the polycarbonate test panels, the coated panels are air dried for 30 minutes to evaporate the solvent, followed by a one hour bake at 250F to cure the organopolysiloxane. The coated panels are then subjected to the abrasion test as in Example 1 and the results are set forth in Table II.
TABLE II
Example No. ~ ~ Haze 1 34.0 4.1 6 2.3 A primer coating composition is prepared by blending 10 parts by weight of Uvimer ~ 545 resin (an acrylated urethane polymer derived from 2,4-toluene diisocyanate, hydroxy ethyl acrylate, and pentaerythritol triacrylate) sold by Polychrome Corp., 10 parts by weight of diethyleneglycol diacrylate, 10 parts by weight of a 50% ethanolic solution of N- ~ -(triethoxysiloxysilyl)propul7 maleamic acid which has been aged, i.e., allowed to stand for an extended period of time, 2 parts by weight of resorcinol monobenzoate, and 1/2 part by weight of diethoxyacetophenone. This blend is diluted with isobutanol to give a final solution having a weight to 1~3~S~ 8SP 2901 volume percent of 2% of said blend in 98% of isobutanol.
A wet film 23 mils in thickness of this primer composi-tion is applied to polycarbonate panels prepared in accordance with Example 1. After evaporation of the solvent, the primer film, being about 0.46 mils in thickness is cured as in Example 2.
The primed polycarbonate panels prepared in accordance with Example 7 are coated with an organopoly-siloxane coating composition containing a further curable organopolysiloxane and an alkanol solvent, the further curable organopolysiloxane being a precured hydrolysis and partial condensation product of methyltrimethoxysilane.
After the organopolysiloxane coating composition is applied to the primed surface of the polycarbonate panels, the coated panels are air dried for 30 minutes to evaporate the solvent, and are then baked for one hour at 250F to cure the organopolysiloxane.
A silica filled organopolysiloxane top coat composition containing 37 weight percent solids, 50%
of which are SiO2, is formulated by adding a commer-cially available aqueous disperson of colloidal silica, having SiO2 of approximately 13-14 millimicron particle size, to methyltrimethoxysilane which has been acidified by the addition of 2.5 weight percent glacial acetic acid.
This composition is mixed for four hours and is then adjusted to a pH of 3.9 by addition of more glacial acetic acid. This acidified composition is then diluted to 18%
solids by the addition of isopropanol and aged for four days to ensure formation of the partial condensate of CH~Si~OH)3-~13~ 8SP 2901 A primed polycarbonate panel prepared in accordance with Example 7 is coated with a silica filled further curable organopoly-siloxane top coat composition prepared in accordance with Example 9.
The panel is air dried for 30 minutes to evaporate the solvent from the silica filled further curable organopolysiloxane top coat composition, followed by a one-hour bake at 250F to cure the further curable organopolysiloxane thereby forming a silica filled thermoset organopolysiloxane top coat.
The durability of adhesion of the silica filled theremoset organopolysiloxane top coat to the polycarbonate substrate is greatly increased by the use of the specific primer layer of the present inven-tion, as may be seen by the following example.
Unprimed polycarbonate panels are pxepared in accordance with Example 1 and are flow-coated with a silica filled organopolysiloxane topy coat composition prepared in accordance with Example 9. The coated unprimed panels are air dried for 30 minutes to evaporate the solvent, followed by a one hour bake at 250F to cure the further curable organopolysiloxane.
These coated, unprimed panels, as well as the coated, primed, panels described below, are subjected to various tests designed to determine the durability of the coating on the substrate. One of these durability tests is a weathering test which includes exposing the coated samples in a 6 kilowatt Xenon arc ~eather-O-Meter ~
manufactured by Atlas Electric Devices Co. After exposure to the Weather-O-Meter ~ for a predetermined time, the coated samples are subjected to an adhesion test. This test consists of using a multiple blade tool to cut parallel grooves about 1 ~m apaxt thro~lgh the coating into the substrate, rotating the sample 11~8590 90 and repeating the cutting process thereby forming a grid "attern of 1 mm squares cut into the coating; and applying an adhesive tape over the cross-hatched area and quickly pulling said tape off. A sample fails the adhesion test if any of the squares in the grid are pulled off. The results of the Weather-O-Meter~
and adhesion test are set forth in Table II below.
Another test designed to determine the durability of the silica filled organopolysiloxane coating on the substrate involves subjecting the coated samples to a humidity test. This test involves subjecting samples to a number of humidity oven cycleæ, and after each cycle subjecting said samples to the afore-described adhesion test. One humidity oven cycle consists of placing the sample into a cabinet maintained at 99% relative humidity and 80-85F, raising the temperature to 140F, maintaining the temperature at 140F for 6 hours, and thereafter lowering the temperature to 80-85F, at which time one cycle is complete and the sample is removed and undergoes the adhesion test.
The results of this test are set forth in Table III below.
Yet another test used to ascertain the durability and adhesion of the silica filled organopolysiloxane coating on the substrate is the sunlamp aging t~st. This test is one wherein the sample undergoes severe exposure to ultraviolet radiation. In the sunlamp aging test, the coated samples are exposed to an RS-sunlamp, and after exposure for a predetermined period of time are removed and subjected to the adhesion test. The results of this test are set forth in Table ~.
Primed polycarbonate panels are prepared in accordance with Example 2 and are flow coated with a silica filled organopoly-il38S9O
siloxane top coat composition prepare~ in accordance with Example 9. These panels are air dried for 30 minutes to evaporate the solvent, followed by a one-hour ba~e at 250F to cure the further curable organopolysiloxane. These primed, top coated S panels are then exposed to the afore-described weathering test, humidity test, abrasion test and sunlamp aging test and the results are set forth in Tables IIA, III, IV and V, respe-ctively.
Primed polycarbonate panels are prepared in accordance with Example 3 and are flow-coated with a silica filled organopolysilox-ane top coat composition prepared in accordance with Example 9.
These panels are air dried for 30 minutes to evaporate the solvent, followed by a one-hour bake at 250F to cure the further curable organopolysiloxane. These primed, top coated panels are then subjected to the afore-described weathering test, humidity test, an abrasion test, and the sunlamp aging test and the results are set forth in Tables IIA, III, IV and V, respectively.
TABLE I IA
Weathering Test No. of hours exposu~e in the Weather-O-Meter at . which sample fails adhesion Example No. .test .
12 Over 700 13 Over 700 TABLE III
Humidity Test No. of cycles in humidity oven .
after which sample fails Example No. adhesion test 12 - Passes adhesion test after 30 cycles 13 Passes adhesion test after 30 cycles 113859~
TABLE IV
Abrasion Resistance _ Example No. ~ % Haze 12 4.1 13 2.3 TABLE V
Sunlamp Aging Test No. of hours exposure to RS-sunlamp at which sample Example No. fails adhesion test _ _ _ ._ . . . . . _ .
11 36 hours 12 ~etween 100 - 200 hours 13 Between 100 - 200 hours Furthermore, a sample prepared in accordance with Example 1~2 which had been exposed in the Weather-O-Meter~ for about 1000 hours was subjected to the abrasion test. It was found that the ~ %
haze of this weathered sample was 4.2, which is almost the same as the 4.1 ~ % haze for the unweathered sample, as set forth in Table IV above.
From the foregoing E~amples and Tables, it is quite evident that the durability of a silica filled organopolysiloxane top coat which is applied onto a polycarbonate substrate primed in accordance with the present invention is greatly improved over the same top coat applied to an unprimed polycarbonate substrate.
The foregoing disclosure of this invention is not to be considered as limiting, since many variations may be made by those skilled in the art without departing from the scope or spirit of the foregoing description.
11. CH2-CHCOO-CH2-f-OOCCH=CH2 C~20X
il38590 fH20~
12. CH2=CHCOO-CH2-f-OOCCH=CH2 - CH2Br 13. CH2=CHCOO-CH2-CH=CH-CH2-CH2-OOCCH=CH2 14. CR2=CHCOO-CH2-CH=CH-fH-OOCH=CH2 fH20H
15. CH2--CHCOO-CH2-f-CH2OOCCH=CH2 CH2Cl _ _ 5 16._ CH2-CHCOO-CH2-CH - CH2-OOCCH=CH2 17. CH2=CHCOO ~ OOCCH=CH2 18. CH2=CHCOO ~ OOCCH=CH2 Br 19. CH2=CHCOO~OOCCH=CH2 OH
20. CH2=CHCOO ~ OOCCH=CH2 1021. CH2=CHCOO-CHCH2CH2-OOCCH=CH2 ~3 22. CH2=CHCOQ-CH2CH2CH CH2-OOCCH=CH2 . Triacrylates_of Formula III
23. CH2=cHcoo-fH2 C82=CHCOO-CH2-f-CH2-CH3 CH2=CHCOO-CH~
1 1 ~ ~ 8SP-2901 24.fH2OH
CH2=CHCOO-CH2-C-C~I2-OOCCH=CH2 1H2-OOCCH=CH2 OOCCH=CH2 25. CH2=CHCOO~ --OOCCH=CH2 Tetraacrylates of Formula III
26.CH2=CHCOO-IH2 CH2=CHCOO-CH2-C--CH2-OOCCH=CH2 27. CH2=CHCOO-CH2 CH-CH CH2-OOCCH=CH2 CH2=CHOO-CH2CH2-OOCCH=CH2 ~H
28. CH2=CHCOO-CH2fHCH-CH2fH-OOCCH=CH2 CH2=cHcoo-cH2 CH2-OOCCH-CH2 These polyacrylate esters and their production are well known to those skilled in the art. One method of producing the di-, tri-, and tetraacrylate esters involves reacting acrylic acid with a di-, tri-, or tetrahydroxyl compound to produce thediester, triester or tetraester. Thus, for example, acrylic acid can be reacted with ethylene glycol to produce ethylene glycol diacrylate (compound 2 in Table I).
It is to be understood that the instant primer compositions may contain only one polyfunctional acrylic acid ester msnomer or a mixture of two or more, preferably two, differen~ monomers. In certain instances, it is preferred that the primer compositions contain mixtures of two or more, preferably two, different monomers.
The organic silicon compounds of the present invention are represented by the formula ~ 1 ~ ~ 8SP-2901 R2CSiX4_c IV.
wherein X independently represents an alkoxy, acyloxy and aryloxy group, R2 represents an organic group containing olefinic unsatura-tion, and c is an integer from 1 to 3.
Preferred alkoxy groups are those containing from 1 to about 10 carbon atoms. Exemplary preferred alkoxy groups include methoxy, propoxy, butoxy, pentoxy, heptoxy, and the like. Preferred acyloxy groups are those containing from 2 to about 10 carbon atoms. Exemplary preferred alkoxy groups include acetoxy, propionoxy, butyroxy, pentanoxy, hexanoxy and the like. The preferred aryloxy group is phenoxy.
R2 represents an organic group containing olefinic unsatur-ation such that the compound of formula IV will co-react with the polyfunctional acrylic acid ester monomer and with ~Y acrylate modified polymer upon exposure to W light and in the presence of a W photoinitiator to form a thermoset reaction product which im-proves the adhesion of an organopolysiloxane to the polycarbonate sub-strate. R is preferably selected from the group consisting Of-acry-loxy-alkyls and methacryloxy alkyls represented by the general formula Y p CH2 = C - C - O - R3 V.
wherein R3 is an alkylene group~ preferably containing 1 to about 12 carbon atoms, and more preferably containing from 2 to 6 carbon atoms, and Y is hydrogen or methyl; and an alkyl maleamic acid represented by the formula ¦¦ H
HC ~ ~ - R3 - VI.
ll HC ~ ~ H
~ SP 2901 wherein R is as defined above.
The primer compositions of the present invention may contain only one organic silicon compound of formula IV
or they may contain mixtures of two or more, but preferably two, different compounds of formula IV. Thus, for example, the primer compositions may contain two different compounds of formula V, two different compounds of formula VI, or one compound of formula V and one compound of formula VI.
The third optional component of the coating composi-tions of the present invention is an acrylate modified poly-.eric resin. The acrylate modified polymeric resins are convetnional polymer types whose structure and preparation are known in the art. These acrylate modified polymers have UV reactive acrylate groups incorporated into the polymer.
Generally, these acrylate modified polymers are represented by the general formula _ Polymer ¦ Acrylate VII.
wherein z is an integer of from 1 to about 5 and Polymer is a z valent polymeric material, and Acrylate is a mono-, di-, tri- or tetraacrylate group. Thus, a difunctional polymer, (z is 2) would have a structure represented by the formula Acrylate - Polymer - Acrylate, VIII.
a trifunctional polymer, (z is 3) would have the structure represented by the formula Acrylate - Polymer - Acrylate, Acrylate and so forth.
Thus, a polymer having monofunctional acrylates attached thereto would be represented by the formula Polymer - O - C - CH - CH2l IX.
11:~8590 wherein Polymer and z are as defined above. A polymer having polyfunctional acrylates attached thereto would be represented by the formula O
Polymer-t~-Rl ~ O _ C - CH = CH~ n \) Z X.
wherein Polymer, Rl, n and z are as defined above.
Polymers having both monofunctional and poly-functional acrylate groups attached thereto are also useful in the practice of the preSent invention. These types of acrylate modified polymers are represented by the structural formula C H2C=CH-C-O~ R -Polymer ~-R - L C~CH=C~ n 1) P
wherein Polymer, R , and n are defined above, and m and p are integers having a value of from 1 to 3, provided that the sum of m + p does not exceed 5.
Exemplary typical acrylate modified polymers, wherein the acrylate is a monoacrylate, are acrylate poly-esters represented by the formula O O O O
2 ( 2)6 r C tcH2 4 c 0-(cH2)~ O-C-CH=CH
acrylate epoxies represented by the formula O OH CH OH O
20CH2=CH-C-O ECH2 CH CH2 ~3_1 3 ~nlCH2-1H-CH2--C-CH=CH2 and acrylate urethanes represented by the formula O O O O
CH2=CH-C-OCL2CH2 [~-O-C-NH~ 3-C-O-CH2CH~l n,O-C-CH=CH2 where n' is a number such that the molecular weight of the polymer is in the approximate range of about 400 to about several thousand, although this range is not at all critical.
Preferred acrylate modified polymers are the acrylate epoxies as described in U.S. 3,586,526 issued June 22, 1971, acrylate urethanes as described in U.S.
3,297,745, issued Jan. 10, 1967, acrylate alkyd urethanes as described in U.S. 3,673,140 issued June 27, 1972, acrylate polycaprolactones as described in U.S. 3,700,643 issued Jan. 23, 1973, acrylate polyesters, and acrylate polyethers as described in U.S. 3,380,831 issued April 30, 1968.
Generally, the primer compositions of the present invention contain a ratio, by weight, of acrylate poly-functional acrylic acid ester monomer to acrylate modified polymer of up to about 1:10; preferably the ration of these components will be in the range of about 1:2 to about 2:1.
The amount of polyfunctional acrylic acid ester monomer plus acrylate modified polymer present in the primer composi-tions is generally from about 10 to about 80 weight percent, preferably from about 20 to about 40 weight percent, while the amount of organic silicon compound present is generally from about 20 to about 90 weight percent, preferably from about 40 to about 80 weight percent.
The photocurable primer compositions also contain a photoinitiating amount of a suitable photoinitiator, i.e.
an amount effective to effect the photocure of the coating composition. Generally, this amount is from abcut 0.01% to about 10% by weight, preferably from about 0.1% to about 5% by weight of the photocurable primer composition, exclu-sive of any solvent present. These additives and the cure thereof are generally well known in the art. Some non-limiting examples of these UV radiation photosensitizers 1 ~ ~ ~ 8SP 2901 include ketones, such as benzophenone, acetophenone, benzil, benzyl methyl ketone; benzoins and substituted benzoins such as benzoin methyl ether, ~ -hydroxymethyl benzoin iso-propyl ether; halogen containing compounds such as ~ -bromo-acetophenone, p-bromoacetophenone, ~ -chloromethylnaph-thalene; sulfur compounds such as aromatic disulfides;
and other photosensitizers such as azides, thioketones, or mixture of synergistic mixtures thereof; the diaryl peroxides;
the hydroperoxides; the peracids and peresters; the azo compounds, or any other known free radical initiator, such as di-t-butyl peroxide, benzoyl peroxide, 2,4-dichloro-benzoyl peroxide, t-butyl hydroperoxide, peroxyacetic acid, perioxybenzoic acid, t-butyl peroxypivalate, t-butyl per-acetate, azobisisobutyronitrile and the like.
The primer compositions of the present invention may contain a resorcinol monobenzoate. The resorcinol mono-benzoate is preferably unsubstituted, although a lower alkyl substituted resorcinol monobenzoate may also be used.
Generally, the resorcinol monobenzoate is present in an amount of from about 1 to about 10 percent by weight. Although the resorcinol monobenzoate or substituted resorcinol mono-benzoate or substituted resorcinol monobenzoate is generally not believed to be directly involved in the reaction between the polyfunctional acrylic acid ester monomer and the silicon containing compound, and, therefore, is not believed to be generally directly incorporated into the cured cross-linked polymer structure formed by the coreaction of the polyfunctional acrylic acid ester monomer and the silicon containing compound, it nevertheless functions in a manner to promote and increase the durability of adhesion of the organopolysiloxane top coat to the primary layer, especially upon exposure of the coated polycarbonate article 1 ~ _ 1 ~ ~ ~ 8SP 2901 to light. More specifically, during the cure of the primer layer by the action of ultraviolet light, the resorcinol monobenzoate present in said layer is converted by the ultra-violet radiation to a dihydroxybenxophenone. This dihydroxy-benzophenone then acts, in the cured primer, as an ultra-violet light absorber and promotes the durability and adhesion of the organopolysiloxane top coat to the primer layer.
The primer compositions of the instant invention may also optionally contain various flatting agents, surface active agents and thioxtropic agents. All of these additive and the use thereof are well known in the art and do not require extensive discussions. Therefore, only a limited number will be referred to, it being understood that any compounds possessing the ability to function in such a manner, i.e., as a flatting agent, surface active agent and the like, can be used so long as they do not deleter-iously affect the photocuring of the primer compositions and do not adversely affect the non-opaque character of the coated polycarbonate article where it is desirable that this be retained.
The various surface-active agents, including anionic, cationic and nonionic surface-active agents are described in Kirk-Othmer Encyclopedia of Chemical Technology, Vol. 13, Interscience Publishers, New York, 1969, pp. 507-593, and Encyclopedia of Polymer Science and Technology, Vol. 13, Interscience Publishers, New York, 1960, pp. 477-486.
In the practice of the present in~ention, the photo-curable primer compositions are first compounded by adding together the polyfunctional acrylic acid ester monomer, thP organo silicon compound, the UV photoinitiator, and - 16 ~
~ SP 2901 where indicated one or more of the other aforementioned additives. Additionally, if so desired to reduce the vis-cosity of the primer formulation or to aid in stabilizing the organo silicon compounds, an organic solvent may be incorporated into the formulation. Generally, the amount of solvent, if any, should be such that evaporation of the solvent occurs before any deleterious effect on the substrate due to the aggressiveness (in the chemical etching sense) of the primer compositions develops. The various components are thoroughly mixed so as to form a generally homogeneous primer composition. A thin, uniform film of the primer solution is then applied onto the polycarbonate surface by any of the known means such as dipping, spraying, roll-coating and the like. Generally, the primer composition is applied in an amount sufficient to provide a cured film of from about 0.005 mil to about 0.5 mil, preferably from about 0.05 mil to about 0.2 mil thick. The primer film is then cured in an inert, e.g., nitrogen, atomosphere, by UV irradiation which can have a wavelength of from 1849A. to 4000A. The lamp systems used to generate such radiation can consist of ultraviolet lamps which can consist of discharge lamps, as for example, xenon, metallic halide, metallic arc, such as low or high pressure mercury vapor discharge lamps, etc., having generating pressure of from as low as a few milli- torr up to about 10 atmospheres, can be employed. After UV curing, there is present on the surface of the polycarbonate a non-opaque primer which is adhered to the polycarbonate. This UV cured primer is believed to be the polymerizable product of the aforedescribed (i) polyfunctional acrylic acid ester monomer or mixtures of polyfunctional acrylic acid ester monomers; (ii) organic silicon compound or mixtures of organic silicon ~ ~ ~ ~ 8SP 2901 compounds; and when employed, (iii) the crylate modified polymers or mixtures of acrylate modified polymers. The ultraviolet radiation cured primer may further contain the photoreaction products of the resorcinol or substituted mono-benzoate, or mixtures thereof, where employed in the afore-described manner. These products consist mainly of dihydroxybenzophenone, or in the case of alkyl substituted resorcinol monobenzoate, alkyl substituted dihydroxybenzo-phenone. The resulting cured primer coat is a thermoset, hard, non-tacky material which is tenaciously adhered to the polycarbonate substrate.
The organopolysiloxane compound which is useful in the formulation of the silicone top coat that is applied to the foregoing cured primer composition is generally a silane selected from silanes of the formula R4aSi(OR )4-a XI.
and the silanes of the formula R4bSi(OCOR )4 b XII.
and partial hydrolysis and condesation products thereof where R3 is selected from monovalent hydrocarbon radicals and halogenated monovalent hydrocarbon radicals and is preferably an alkyl radical of 1 to about 8 carbon atoms or phenyl radicals, where a is a zero or 1, and R4 and R5 may be monovalent hydrocarbon radicals and halogenated mono-valent hydrocarbon radicals but are preferably alkyl radicals of l to about 8 carbon atoms and phenyl radicals, where b may vary from 0 to 2. The above silanes or partial hydrolysis and condensation products of such silanes are applied in anywhere from about 10% to about 100% solids, wherein the solvent is water or an organic solvent, pre-ferably alkanol. Such silane top coat composition is then allowed to cure at a temperature anywhere from 20 to ~ 1 ~ ~ 8SP 2901 to 130C. The silicone top coat composition has to be cured preferably at an elevated temperature to effect the proper cure, but the temperature has to be below the glass transi-tion temperature of the polycarbonate.
Such alkoxylated and acyloxy functional silanes are well known materials to silicone manufacturers and are easily obrainable. Thus, for instance, these silanes are noted in U.S. Patents 3,720,699 issued March 13, 1973;
3,650,808 issued March 21, 1972 and 3,701,7~3 issued October 31, 1972.
These are not the only silicone top coats that may be utilized with the primer composition of the instant case. Less preferred silicone top coats which can be hydro-lyzed or partially dissolved in a solvent in the foregoing solids content of 10 to 100% solids are, for instance, silicone resins composed of trifunctional and difunctional units, silicone resins composed of trifunctional units, difunctional units and tetrafunctional units where the organo substituent groups in the trifunctional units may be selected from alkyl radicals of 1 to 8 carbon atoms and are preferably, methyl, phenyl and vinyl; and wherein the organo substituent groups in the difunctional siloxy units may be selected again from alkyl radicals of 1 to 8 carbon atoms, vinyl radicals and phenyl radicals. Such silicon resins usually have an organic to silicon atom ratio of 1:1 to 1.9:1; may have a silanol content that varies anywhere from 4 to 10 weight percent and optionally may have an alkoxy content that varies from 2 to 4~. The prepara-tion of such silicone resins which may be utilized at top coats in the invention of the instant case are, for instance, to be found in the patents of Duane F. Merrill, i.e.
~ 1 ~ ~ 8SP 2901 U.S. Patents 3,375,223 issued March 28, 1968; 3,435,001 issued Mar. 25, 1969; 3,450,672 issued Jun~ 17, 1969;
3,790,527 issued Feb. 5, 1974; 3,832,319 issued Aug. 27, 1974; 3,865,766 issued Feb. 11, 1975; 3,887,~14 issued Jan. 3, 1975 and 3,925,276 issued Dec. 9, 1975. However, it must be pointed out that such silicone resins are not the preferred ilicone top coat materials of the invention of the instant case. The foregoing alkoxy silanes of Formula XI and the foregoing acyloxy functional silanes of Formula XII are the most preferred. Other well known silicone top coat compositions for metals, plastics, ceramics and glass may be utilized with the primer composition of the instant case. As stated previously, the foregoing alkoxy functional silanes of Formula XI and the acyloxy functional silanes of Formula XII are preferred.
When the curable organopolysiloxane composition applied as a top coat is silica filled, the silica will normally be an aqueous hydrosol, ie a colloidal silica.
Aqueous colloidal silica dispersons generally have a particle size in the range of 5 to 150 millimicrons in diameter. These silica dispersions are prepared by methods well-known in the art and are commercially available. It is preferred to use colloidal silica having a particle size in the range of 10 to 30 millimicrons in diameter in order to obtain dispersions having a greater stability and to provide top coatings having superior optical properties.
The silica filled organopolysiloxane top coat compositions may be prepared by adding trialkoxysilanes to colloidal silica hydrosol and adjusting the pH to a range of 3.0 to 6.0 by the addition of acid to prevent gellation. The suitable acids include both il38S90 organic and inorganic acids such as hydrochloric, choroacetic, acetic, citric, benzoic, formic, propionic, maleic, oxalic, glycolic and the like. The acid may be added to either the silance or the silica hydrosol before the two components are mixed. In this medium the silanes of formulae XI and XII will of course be hydrolysed to form silanes of the formula:
Ra Si(OH)4 a XIII.
and partial siloxane condensation products thereof.
Desirably a in formula XIII will have a value 1. Also desirably, R4 is selected from lower alkyl of 1-3 carbons vinyl; 3,3,3,-trifluoropropyl, gamma-glycidoxypropyl and gamma-methacryloxypropyl, with at least 70% of the R4 radicals being methyl. Most preferably R is methyl.
The most suitable trialkoxysilanes are those containing methoxy, ethoxy, isoporpoxy and t-butoxy groups. The hydrolysis of the preferred silanes, ie those of formula XI wherein a is 1, will generate the corresponding trisilanols and alcohol. Depending upon the percent solids desired in the final coating composition, additional alcohol, water, or a water-miscible solvent can be added. Suitable alcohols are the lower aliphatci alcohols such as methanol, ethanol, isopropanol, t-butanol, and mi~tures thereof.
Generally, the solvent system should contain from about 20 to about 75 weight percent alcohol to ensure solubility of the siloxanol formed by the condesnation of the silanol.
~f desired, a minor amount of an additional water-miscible polar solvent such as acetone, butyl Cellosolve ~ , and the like can be added to the water-alcohol solvent system.
Generally, sufficient alcohol or water alcohol solvent is added to give a composition containing from about 10 to 50 percent by weight of solids, said solids generally tl~S~ 8SP 2901 comprising from about 10 to about 70 percent by weight of colloidal silica and from about 30 to about 90 percent by weight of the partial condensate of the silanol. The composition is allowed to age for a short period of time to ensure formation of the partial condensat of the silanol, i.e., the siloxanol. This condensation occurs upon generation of the silanol in the acidic aqueous medium through the hydroxyl substituents to form Si-O-Si bonding. The condensation is not complete, resulting in a siloxane having an appreciable quantity of silicon-bonded hydroxyl group.
The foregoing top coat composition whether or not silica filled is then applied onto the primed polycaronate by any of the commonly known methods such as dipping, spraying, flow-coating and the like. After the top coat composition is applied to the primed polycarbonate, the polycarbonate is air dried if necessary to evaporate the volatile solvents from the top coat composition. There-after, heat is applied to cure the top coat. During curing, the residual hydroxyls of the siloxane condense to give a silsesquioxane, R SiO3/2. The result is a silica filled cross-linked organopolysiloxane top coat which is tena-ciously adhered to the substrate and is highly resistant to scratching, abrasion, chemical solvents, and marring.
Generally, the silica filled top coat contains from about 10 to about 70 weight percent silica and from about 30 to about 90 weight percent of the organopolysiloxane present as the silsesquioxane RSio3/2.
The thickness of the top-coat generally is dependent upon such factors as upon the method of application and the weight percent solids present in silica filled further curable organopolysiloxane top coat composition. In general, the higher the percent solids, and the longer the application i~ ~ ~ 8SP 2901 time, the greater the thickness of the top coat. Thicker coats can in general be prepared when using the silica filled materials. It is preferred that the cured top coat have a thickness of from about 0.1 to about 0.5 mils, more preferably from 0.15 to about 0.4 mils, and most preferably from about 0.2 to about 0.25 mils.
Another embodiment of the present invention is a process of producing a mar, abrasion, scratch and chemical resistant polcarbonate article. The process comprises the steps of: (i) applying onto the polycarbonate an ultraviolet light curable primer composition containing (a) at least one polyfunctional acrylic acid ester monomer represented by formula III, (b) an organo silicon compound containing at least one olefinically unsaturated organic group, said compound being represented by formula IV, (c) and optionally a further reactive acrylate modified polymer; (d) an ultra-violet light photoinitiator, and preferably te) a resorcinol monobenzoate; (ii) applying ultraviolet light of sufficient strength and for a period of time effective to cure said primer composition and form a cured primer layer on said polucarbonate substrate; then (iii) applying a silica filled further curable organopolysiloxane top coat composi-tion onto said cured primer layer, (iv) evaporating off the volatile solvents present in the top coat composition;
and tv3 curing the top coating by the application of heat thereto to form a silica filled thermoset organopolysiloxane, i.e., a silsequioxane.
In order to more fully and clearly illustrate the present invention, the following specific examples are presented. It is intended that the examples be considered as illustrative rather than limiting the invention disclosed and claimed herein.
~ 1 ~ 5 ~ 8SP 2901 An aromatic polycarbonate is prepared by reacting 2,2-bis(4-hydroxyphenyl) propane and phosgene in the presence of an acid acceptor and a molecular weight regulator and having an intrinsic viscosity of 0.57. The product is then fed to an extruder, which extruder is operated at about 265C and the extrudate is comminuted into pellets.
The pellets are then injection molded at about 315C into test panels of about 4 in. by 4 in. by about 1/8 in. thick. The test panels are subjected to an abrasion test.
The abrasion test is one wherein test panels having a 1/4 inch diameter hole cut in the center are sub-jected to a Taber Abraser. The Taber Abraser is equipped with CS-lOF wheels which are resurfaced every 200 cycles by abrading for 25 cycles on a S-ll refacing disc. The weights are used in combination with the CS-lOF wheels are 500 gm. weights. Initial measurements of ~ Haze are made at four places around the future wear track of the sample using a Gardner Hazemeter. The sample is abraded for 500 cycles, cleaned with isoporpanol, and the ~ Haze is remeasured at the same four places. The four differences in % Haze are calculated and averaged to give the Haze. The results are set forth in Table II.
~38S~ 8SP 2901 A primer composition is prepared by blending 50 gms. of 1,6-hexanediol diacrylate, 50 gms. of a 50~
ethanolic solution of N- L- (triethoxysilyl) propy~ maleamic acid which has been aged, i.e., allowed to stand for an extended period fo time, 1.5 gms. of ~ , ~ -diethyoxyaceto-phenone, 7.5 gms. of resorcinol monobenzoate, and 7.5 gms. of resorcinol monobenzoate, and 750 gms. of isobutanol.
To 250 gms. of this solution are added 250 gms. of isobutanol.
A thin film of this primer composition is applied to poly-~
carbonate test panels prepared in accordance with Example 1.
The film is cured by passing the polycarbonate panels through a combination Linde photocuring apparatus (this consists of a variable speed conveyor running through a chamber containing germicidal type mercury vapor lamps which emit light mainly at 2537A, 3150A, and 3605A) wherein the nitrogen pressure is 25 psi nitrogen and the speed of the conveyor is 30 ft/min. The film is tack free and cured after this treatment.
~38590 :
A primer composition is prepared by blending 250 gms. of 1,6-hexanediol diacrylate, 125 gms. of an aged 50% ethanolic solu-tion of N-/3-(triethoxysilyl) propyl7 maleamic acid, 62 gms. of pentaerythitol-triacrylate, 7.5 gms. of ~, ~ -diethoxy-acetophen-one, 1.2 gms. of resorcinol monobenzoate and 600 gms. of isobutanol. 250 gms. of the resulting solution is diluted in 1900 gms. of isobutanol. A thin f ilm of this primer composition is applied to polycarbonate test panels prepared in accordance with Example 1. The film is cured by priming through a Linde photo-curing apparatus as set forth in Example 2.
- ~ primer composition is prepared by blending 250 gms. of 1,6-hexanediol diacrylate, 125 gms. of y-methacryloxy-propyl trimeth-oxysilane, 62 gms. of trimethylolpropane triacrylate, 7.5 gms. of ~ , ~-diethoxyacetophenone, 36.5 gms. of resorcinol monobenzoate, and 600 gms. of isobutanol. To 250 gms. of the resulting solution are added 1900 gms. of isobutanol.
EX~PLE 5 The primed polycarbonate panels prepared in accordance with Example 2 are coated with an organopolysiloxane coating composition containing a further curable organopolysiloxane and an alkanol solvent, the further curable organopolysiloxane being a precured hydrolysis and partial condensation product of a methyltrialkoxy silane, e.g., methyltrimethoxysilane. ~fter the organopolysiloxane coating composition is applied to the primed surface of the poly-carbonate test panels, the coated panels are air dried for 30 minutes to evaporate the solvent, followed by a one hour bake at 250F t~ cure the organopolysiloxane. The coated panels are then ~138S~ 8SP 2901 subjected to the abrasion test as in Example 1 and the results are set forth in Table II.
The primed polycarbonate panels prepared in accor-dance with Example 3 are coated with an organopolysiloxane coating composition containing a further curable organopoly-siloxane being a precured hydrolysis and partial condensation product of a methyltrialkoxysilane, e.g., methyltrimethoxy-silane. After the organopolysiloxane coating composition is applied to the primed surface of the polycarbonate test panels, the coated panels are air dried for 30 minutes to evaporate the solvent, followed by a one hour bake at 250F to cure the organopolysiloxane. The coated panels are then subjected to the abrasion test as in Example 1 and the results are set forth in Table II.
TABLE II
Example No. ~ ~ Haze 1 34.0 4.1 6 2.3 A primer coating composition is prepared by blending 10 parts by weight of Uvimer ~ 545 resin (an acrylated urethane polymer derived from 2,4-toluene diisocyanate, hydroxy ethyl acrylate, and pentaerythritol triacrylate) sold by Polychrome Corp., 10 parts by weight of diethyleneglycol diacrylate, 10 parts by weight of a 50% ethanolic solution of N- ~ -(triethoxysiloxysilyl)propul7 maleamic acid which has been aged, i.e., allowed to stand for an extended period of time, 2 parts by weight of resorcinol monobenzoate, and 1/2 part by weight of diethoxyacetophenone. This blend is diluted with isobutanol to give a final solution having a weight to 1~3~S~ 8SP 2901 volume percent of 2% of said blend in 98% of isobutanol.
A wet film 23 mils in thickness of this primer composi-tion is applied to polycarbonate panels prepared in accordance with Example 1. After evaporation of the solvent, the primer film, being about 0.46 mils in thickness is cured as in Example 2.
The primed polycarbonate panels prepared in accordance with Example 7 are coated with an organopoly-siloxane coating composition containing a further curable organopolysiloxane and an alkanol solvent, the further curable organopolysiloxane being a precured hydrolysis and partial condensation product of methyltrimethoxysilane.
After the organopolysiloxane coating composition is applied to the primed surface of the polycarbonate panels, the coated panels are air dried for 30 minutes to evaporate the solvent, and are then baked for one hour at 250F to cure the organopolysiloxane.
A silica filled organopolysiloxane top coat composition containing 37 weight percent solids, 50%
of which are SiO2, is formulated by adding a commer-cially available aqueous disperson of colloidal silica, having SiO2 of approximately 13-14 millimicron particle size, to methyltrimethoxysilane which has been acidified by the addition of 2.5 weight percent glacial acetic acid.
This composition is mixed for four hours and is then adjusted to a pH of 3.9 by addition of more glacial acetic acid. This acidified composition is then diluted to 18%
solids by the addition of isopropanol and aged for four days to ensure formation of the partial condensate of CH~Si~OH)3-~13~ 8SP 2901 A primed polycarbonate panel prepared in accordance with Example 7 is coated with a silica filled further curable organopoly-siloxane top coat composition prepared in accordance with Example 9.
The panel is air dried for 30 minutes to evaporate the solvent from the silica filled further curable organopolysiloxane top coat composition, followed by a one-hour bake at 250F to cure the further curable organopolysiloxane thereby forming a silica filled thermoset organopolysiloxane top coat.
The durability of adhesion of the silica filled theremoset organopolysiloxane top coat to the polycarbonate substrate is greatly increased by the use of the specific primer layer of the present inven-tion, as may be seen by the following example.
Unprimed polycarbonate panels are pxepared in accordance with Example 1 and are flow-coated with a silica filled organopolysiloxane topy coat composition prepared in accordance with Example 9. The coated unprimed panels are air dried for 30 minutes to evaporate the solvent, followed by a one hour bake at 250F to cure the further curable organopolysiloxane.
These coated, unprimed panels, as well as the coated, primed, panels described below, are subjected to various tests designed to determine the durability of the coating on the substrate. One of these durability tests is a weathering test which includes exposing the coated samples in a 6 kilowatt Xenon arc ~eather-O-Meter ~
manufactured by Atlas Electric Devices Co. After exposure to the Weather-O-Meter ~ for a predetermined time, the coated samples are subjected to an adhesion test. This test consists of using a multiple blade tool to cut parallel grooves about 1 ~m apaxt thro~lgh the coating into the substrate, rotating the sample 11~8590 90 and repeating the cutting process thereby forming a grid "attern of 1 mm squares cut into the coating; and applying an adhesive tape over the cross-hatched area and quickly pulling said tape off. A sample fails the adhesion test if any of the squares in the grid are pulled off. The results of the Weather-O-Meter~
and adhesion test are set forth in Table II below.
Another test designed to determine the durability of the silica filled organopolysiloxane coating on the substrate involves subjecting the coated samples to a humidity test. This test involves subjecting samples to a number of humidity oven cycleæ, and after each cycle subjecting said samples to the afore-described adhesion test. One humidity oven cycle consists of placing the sample into a cabinet maintained at 99% relative humidity and 80-85F, raising the temperature to 140F, maintaining the temperature at 140F for 6 hours, and thereafter lowering the temperature to 80-85F, at which time one cycle is complete and the sample is removed and undergoes the adhesion test.
The results of this test are set forth in Table III below.
Yet another test used to ascertain the durability and adhesion of the silica filled organopolysiloxane coating on the substrate is the sunlamp aging t~st. This test is one wherein the sample undergoes severe exposure to ultraviolet radiation. In the sunlamp aging test, the coated samples are exposed to an RS-sunlamp, and after exposure for a predetermined period of time are removed and subjected to the adhesion test. The results of this test are set forth in Table ~.
Primed polycarbonate panels are prepared in accordance with Example 2 and are flow coated with a silica filled organopoly-il38S9O
siloxane top coat composition prepare~ in accordance with Example 9. These panels are air dried for 30 minutes to evaporate the solvent, followed by a one-hour ba~e at 250F to cure the further curable organopolysiloxane. These primed, top coated S panels are then exposed to the afore-described weathering test, humidity test, abrasion test and sunlamp aging test and the results are set forth in Tables IIA, III, IV and V, respe-ctively.
Primed polycarbonate panels are prepared in accordance with Example 3 and are flow-coated with a silica filled organopolysilox-ane top coat composition prepared in accordance with Example 9.
These panels are air dried for 30 minutes to evaporate the solvent, followed by a one-hour bake at 250F to cure the further curable organopolysiloxane. These primed, top coated panels are then subjected to the afore-described weathering test, humidity test, an abrasion test, and the sunlamp aging test and the results are set forth in Tables IIA, III, IV and V, respectively.
TABLE I IA
Weathering Test No. of hours exposu~e in the Weather-O-Meter at . which sample fails adhesion Example No. .test .
12 Over 700 13 Over 700 TABLE III
Humidity Test No. of cycles in humidity oven .
after which sample fails Example No. adhesion test 12 - Passes adhesion test after 30 cycles 13 Passes adhesion test after 30 cycles 113859~
TABLE IV
Abrasion Resistance _ Example No. ~ % Haze 12 4.1 13 2.3 TABLE V
Sunlamp Aging Test No. of hours exposure to RS-sunlamp at which sample Example No. fails adhesion test _ _ _ ._ . . . . . _ .
11 36 hours 12 ~etween 100 - 200 hours 13 Between 100 - 200 hours Furthermore, a sample prepared in accordance with Example 1~2 which had been exposed in the Weather-O-Meter~ for about 1000 hours was subjected to the abrasion test. It was found that the ~ %
haze of this weathered sample was 4.2, which is almost the same as the 4.1 ~ % haze for the unweathered sample, as set forth in Table IV above.
From the foregoing E~amples and Tables, it is quite evident that the durability of a silica filled organopolysiloxane top coat which is applied onto a polycarbonate substrate primed in accordance with the present invention is greatly improved over the same top coat applied to an unprimed polycarbonate substrate.
The foregoing disclosure of this invention is not to be considered as limiting, since many variations may be made by those skilled in the art without departing from the scope or spirit of the foregoing description.
Claims (72)
1. A polycarbonate article having improved scratch, mar, abrasion and chemical solvent resistance comprising a polycarbonate substrate having deposited thereon (i) an ultra-violet radiation cured primer layer which contains the photochemical reaction product of (a) at least one polyfunctional acrylic acid ester monomer, and (b) an organic silicon compound containing at least one organic group having olefinic unsaturation, said organic silicon compound being represented by the formula R2cSiX4-c wherein X independently represents an alkoxy, acyloxy and aryloxy group, R2 represents said at least one organic group containing olefinic unsaturation, and c is an integer from 1 to 3; and (ii) having deposited on said primer layer a cured top coat comprising a colloidal silica filled thermoset organopolysiloxane.
2. The polycarbonate article of claim 1 wherein said cured primer layer further contains the photochemical reaction products of resorcinol monobenzoate, alkyl substituted resorcinol monobenzoate, or mixtures thereof.
3. The article of claim 2 wherein said polyfunctional acrylic acid ester monomer is represented by the formula wherein n is an integer from 2 to 4 and R is an n valent alkyl, ether, polyether, alkenyl, aryl, alkaryl and aralkyl group.
4. The article of claim 3 wherein R is an n valent alkyl, ether, and polyether group.
5. The article of claim 4 wherein said polyether group is represented by the formula ?R1O?x wherein R1 is a lower alkyl group and x is an integer of from 2 to about 5.
6. The article of claim 1 wherein R2 is an acryloxyalkyl, methacryloxyalkyl, or an alkyl substituted maleamic acid group.
7. The article of claim 5 wherein R2 is an acryloxyalkyl group represented by the formula CH2 = CH - COO - R3 -wherein R3 is a lower alkyl radical.
8. The article of claim 6 wherein R2 is a methacryloxyalkyl group represented by the formula wherein R3 is a lower alkyl radical.
9. The article of claim 1 wherein R2 is an alkyl substituted maleamic acid represented by the formula wherein R3 is a lower alkyl radical.
10. The article of claim 9 wherein said alkyl radical is a propyl radical.
11. The article of claim 10 wherein X is an alkoxy group and wherein c is 1.
12. The article of claim 11 wherein said alkoxy group is an ethoxy group.
13. The article of claim 11 wherein said alkoxy group is a methoxy group.
14. The article of claim 1 wherein said top coat is collidal silica filled.
15. The article of claim 14 wherein said thermoset organopolysiloxane is a condensation product of a silanol having the formula R4Si(OH)3, wherein R4 is an alkyl radical of from 1 to 3 carbon atoms, the vinyl radical, the 3,3,3-trifluoropropyl radical, the gamma-glycidoxypropyl radical and the gamma-methacryloxypropyl radical, at least 70 weight percent of the silanol being CH3Si(OH)3.
16. The article of claim 14 wherein said top coat contains from about 10 to about 70 weight percent of colloidal silica and from about 30 to about 90 weight percent of the condensation product of said silanol.
17. The article of claim 14, 15 or 16 wherein said thermoset organopolysiloxane is the condensation product of CH3Si(OH)3.
18. The article of claim 2 or 3 wherein said primer coat comprises an acrylate modified polymer.
19. The article of claim 14, 15 or 16 wherein said primer coat comprises an acrylate modified polymer.
20. A polycarbonate article having improved scratch, mar, abrasion and chemical solvent resistance comprising a polycarbonate substrate having thereon (i) an ultraviolet radiation cured primer layer, said cured primer layer being the photochemical reaction product of a primer composition containing at least one polyfunctional acrylic acid ester monomer, an organic silicon compound containing at least one organic group having olefinic unsaturation, said organic silicon compound being represented by the formula R3cSiX4-c wherein X is an alkoxy, acyloxy or aryloxy radical, R3 represents said at least one organic group having olefinic unsaturation, and c is an integer from 1 to 3, a photo-initiator, and a compound selected from resorcinol monobenzoate, lower alkyl substituted resorcinol monobenzoate, or mixtures thereof; and (ii) a cured colloidal silica filled thermoset organopolysiloxane top coat on said cured primer layer, said top coat being the thermally cured product of a top coat composition comprising a dispersion of colloidal silica in a lower aliphatic alcohol-water solution of the partial condensate of a silanol of the formula RSi(OH)3 wherein R is selected from alkyl radicals containing 1 to 3 carbon atoms, the vinyl radical, the 3,3,3-trifluoropropyl radical, the gamma-glycidoxypropyl radical and the gamma-methacryloxypropyl radical, at least 70 weight percent of the silanol being CH3Si(OH)3, said composition containing sufficient acid to provide a pH in the range of 3.0 to 6.0
21. The article of claim 20 wherein said polyfunctional acrylic acid ester monomer is represented by the general formula [H2C = CH - COO?nR1 wherein n has a value from 2 to 4, and R1 is an n valent alkyl, ether, polyether, alkenyl, aryl, alkaryl and aralkyl group.
22. The article of claim 20 or 21 wherein R1 is an n valent alkyl, ether and polyether group.
23. The article of claim 20 wherein R3 is an acryloxyalkyl, methacryloxyalkyl, or an alkyl maleamic acid group.
24. The article of claim 23 wherein R3 is an acryloxyalkyl group represented by the formula CH2 = CH - COO - R4 -wherein R4 is a lower alkyl radical.
25. The article of claim 23 wherein R3 is a methacryloxy alkyl group represented by the formula wherein R is a lower alkyl radical.
26. The article of claim 23 wherein R3 is an alkyl maleamic acid group represented by the formula wherein R4 is a lower alkyl radical.
27. The article of claim 26 wherein R4 is a propyl radical.
28. The article of 27 wherein X is an alkoxy radical and c is 1.
29. The article of claim 28 wherein said alkoxy radical is an ethoxy radical.
30. The article of claim 28 wherein said alkoxy radical is a methoxy radical.
31. The polycarbonate article having improved scratch, mar, abrasion and chemical solvent resistance comprising a polycarbonate substrate having thereon (i) an ultraviolet radiation cured primer layer, said cured primer layer being the photochemical reaction product of a primer composition containing at least one polyfunction acrylic acid ester monomer, an acrylate modified polymer, an organic silicon compound containing at least one organic group having olefinic unsaturation, said organic silicon compound being represented by the formula R4cSiX4-c wherein X is an alkoxy, acyloxy or aryloxy radical, R3 represents said at least one organic group having olefinic unsaturation, and c is an integer from 1 to 3, a photoinitiator, and a compound selected from resorcinol monobenzoate, lower alkyl substituted resorcinol monobenzoate, or mixtures thereof; and (ii) cured colloidal silica filled thermoset organopolysiloxane top coat on said cured primer layer said top coat being the thermally cured product of a top coat composition comprising a dispersion of colloidal silica in a lower aliphatic alcohol-water solution of the partial condensate of a silanol of the formula RSi(OH)3 wherein R is selected from alkyl radicals containing 1 to 3 carbon atoms, the vinyl radical, the 3,3,3-trifluoropropyl radical, the gamma-glycidoxypropyl radical and the gamma-methacryloxypropyl radical, at least 70 weight percent of the silanol being CH3Si(OH)3, said composition containing sufficient acid to provide a pH in the range of 3.0 to 6Ø
32. The article of claim 31 wherein said polyfunctional acrylic acid ester monomer is represented by the general formula [H2C = CH - COO ?nR1 wherein n has a value of from 2 to 4, and R1 is an n valent alkyl, ether, polyether, alkenyl, aryl, alkaryl and aralkyl group.
33. The article of claim 32 wherein R1 is an n valent alkyl, ether and polyether group.
34. The article of claim 33 wherein said polyether group is represented by the formula ?R2O?x wherein R2 is a lower alkyl radical and x is an integer of from 2 to about 5.
35. The article of claim 31 wherein R3 is an acryloxyalkyl, methacryloxyalkyl, or an alkyl maleamic acid group.
36. The article of claim 35 wherein R3 is an acryloxyalkyl group represented by the formula CH2 = CH - COO - R4 -wherein R4 is a lower alkyl radical.
37. The article of claim 35 wherein R3 is a methacryloxy alkyl group represented by the formula wherein R4 is a lower alkyl radical.
38. The article of claim 35 wherein R3 is an alkyl maleamic acid group represented by the formula wherein R4 is a lower alkyl radical.
39. The article of claim 38 wherein R4 is a propyl radical.
40. The article of claim 39 wherein X is an alkoxy radical and c is 1.
41. The article of claim 40 wherein said alkoxy radical is an ethoxy radical.
42. The article of claim 41 wherein said alkoxy radical is a methoxy radical.
43. The article of claim 32 wherein said acrylate modified polymer is selected from the group consisting of acrylate polyurethanes, acrylate alkyd polyurethanes, acrylate polycaprolactones, acrylate unsaturated acid modified drying oils, acrylate polyesters, and acrylate polyethers.
44. A UV curable primer composition for improving the adhesion of an organopolysiloxane to a polycarbonate substrate comprising (i) a polyfunctional acrylic acid ester monomer, (ii) an organic silicon compound containing at least one organic group having olefinic unsaturation, said organic silicon compound being represented by the formula R"cSiX4-c wherein X independently represents an alkoxy, ocyloxy, and aryloxy group, R" represents said at least one organic group containing olefinic unsaturation, and c is an integer of from 1 to 3, and (iii) a UV light photoinitiator, wherein said polyfunctional acrylic acid ester monomer is represented by the formula [H2C=CH-?-O?nR' wherein n is an integer from 2 to 8, preferably from 2 to 6, and more preferably from 2 to 4, and R' is a n valent alkyl, ether, polyether, alkenyl, aryl, alkaryl and aralkyl group.
45. The composition of claim 44 further comprising an acrylate modified polymer.
46. The composition of claim 44 further comprising resorcinol monobenzoate or an alkyl derivative thereof.
47. The composition of claim 44, 45 or 46 wherein R' is an n valent alkyl, ether and polyether group.
48. The composition of claim 44, 45 or 46 wherein R' is a polyether group represented by the formula ?R6O?x wherein R6 is a lower alkyl group and x is an integer of from 2 to about 5.
49. The composition of claim 44, 45 or 46 wherein the organo group containing olefinic unsaturation is selected from acryloxyalkyl, methacryloxyalkyl, and alkyl maleamic acid groups.
50. The composition of claim 44 wherein said organic silicon compound containing at least one organic group having olefinic unsaturation is represented by the formula R"cSiX4-c and c is 1 and X is an alkoxy group.
51. The composition of claim 50 wherein R" is an acryloxyalkyl group represented by the formula wherein R"' is an alkyl group.
52. The composition of claim 50 wherein R" is a methacryloxyalkyl group represented by the formula wherein R"' is an alkyl group.
53. The composition of claim 50 wherein R" is an alkylmaleamic acid represented by the formula wherein R"' is an alkyl group.
54. The composition of claim 53 wherein R"' is a propyl group.
55. The composition of claim 54 wherein said alkoxy group is an ethoxy group.
56. The composition of claim 52 wherein R"' is a propyl group.
57. The composition of claim 56 wherein said alkoxy group is a methoxy group.
58. A process for providing a uniformly and tenaciously adhered, scratch resistant, mar resistant and organic solvent resistant organopolysiloxane coating on a polycarbonate surface which comprises:
(i) applying a UV curable primer composition comprised of (a) a polyfunctional acrylic acid ester monomer, (b) an organic silicon compound containing at least one organic group having olefinic unsaturation, said organic silicon compound being represented by the formula R"cSiX4-c wherein X independently represents an alkoxy, acyloxy, and aryloxy group, R" represents said at least one organic group containing olefinic unsaturation, and c is an integer from 1 to 3, and (c) a UV light photoinitiator onto said polycarbonate surface;
(ii) curing said primer composition by exposure to UV light;
(iii) applying a coating composition containing a further curable organopolysiloxane onto said cured primer;
and (iv) bring said further curable organopolysiloxane to a thermoset condition and thereby producing said coating.
(i) applying a UV curable primer composition comprised of (a) a polyfunctional acrylic acid ester monomer, (b) an organic silicon compound containing at least one organic group having olefinic unsaturation, said organic silicon compound being represented by the formula R"cSiX4-c wherein X independently represents an alkoxy, acyloxy, and aryloxy group, R" represents said at least one organic group containing olefinic unsaturation, and c is an integer from 1 to 3, and (c) a UV light photoinitiator onto said polycarbonate surface;
(ii) curing said primer composition by exposure to UV light;
(iii) applying a coating composition containing a further curable organopolysiloxane onto said cured primer;
and (iv) bring said further curable organopolysiloxane to a thermoset condition and thereby producing said coating.
59. The process of claim 58 wherein said poly-functional acrylic acid ester monomer is represented by the formula [H2C=CH-?-O?nR' wherein n is an integer from 2 to 8, and R' is an n valent alkyl, ether, polyether, alkenyl, aryl, alkaryl and aralkyl group.
60. The process of claim 59 wherein R' is an n valent alkyl, ether and polyether group.
61. The process of claim 59 wherein said polyether group is represented by the formula ?R6O?x wherein R6 is a lower alkyl group and x is an integer of from 2 to about 5.
62. The process of claim 59 wherein R' is an acryloxy alkyl, methacryloxyalkyl, and an alkylmaleamic acid group.
63. The process of claim 62 wherein c is 1 and X is an alkoxy group.
64. The process of claim 63 wherein R" is an acryloxyalkyl group represented by the formula CH2=CH-?-O-R"'-wherein R"' is an alkyl group.
65. The process of claim 63 wherein R" is a methacryloxyalkyl group represented by the formula wherein R"' is an alkyl group.
66. The process of claim 63 wherein R" is an alkyl maleamic acid represented by the formula wherein R"' is an alkyl group.
67. The process of claim 66 wherein R"' is a propyl group.
68. The process of claim 67 wherein said alkoxy group is an ethoxy group.
69. The process of claim 65 wherein R"' is a propyl group.
70. The process of claim 65 wherein said alkoxy group is a methoxy group.
71. The process of claim 58 or 59 wherein said applied composition further includes an acrylate modified polymer.
72. The process of claim 59, 62 or 63 wherein said applied composition further includes an acrylate modified polymer.
Applications Claiming Priority (8)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US12,579 | 1979-02-15 | ||
| US06/012,579 US4188451A (en) | 1978-04-12 | 1979-02-15 | Polycarbonate article coated with an adherent, durable, silica filled organopolysiloxane coating and process for producing same |
| US26,059 | 1979-04-02 | ||
| US06/026,059 US4232088A (en) | 1978-04-12 | 1979-04-02 | Polycarbonate articles coated with an adherent, durable organopolysiloxane coating and process for producing same |
| US06/034,434 US4218508A (en) | 1978-04-12 | 1979-04-30 | Polycarbonate articles coated with an adherent, durable silica filled organopolysiloxane coating and process for producing same |
| US34,434 | 1979-04-30 | ||
| US06/042,140 US4235954A (en) | 1978-04-12 | 1979-05-24 | Polycarbonate article coated with an adherent, durable organopolysiloxane coating and process for producing same |
| US42,140 | 1979-05-24 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1138590A true CA1138590A (en) | 1982-12-28 |
Family
ID=27486204
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000332238A Expired CA1138590A (en) | 1979-02-15 | 1979-07-20 | Polycarbonate articles coated with an adherent organopolysiloxane |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1138590A (en) |
-
1979
- 1979-07-20 CA CA000332238A patent/CA1138590A/en not_active Expired
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4188451A (en) | Polycarbonate article coated with an adherent, durable, silica filled organopolysiloxane coating and process for producing same | |
| US4207357A (en) | Method for coating a polycarbonate article with silica filled organopolysiloxane | |
| US4235954A (en) | Polycarbonate article coated with an adherent, durable organopolysiloxane coating and process for producing same | |
| US4478876A (en) | Process of coating a substrate with an abrasion resistant ultraviolet curable composition | |
| US4210699A (en) | Abrasion resistant silicone coated polycarbonate article | |
| US4242381A (en) | Method of providing a polycarbonate article with a uniform and durable silica filled organopolysiloxane coating | |
| US4395463A (en) | Article comprising silicone resin coated, methacrylate-primed substrate | |
| US4239798A (en) | Abrasion resistant silicone coated polycarbonate article | |
| US4070526A (en) | Radiation-curable coating compositions comprising mercaptoalkyl silicone and vinyl monomer, method of coating therewith and coated article | |
| US4232088A (en) | Polycarbonate articles coated with an adherent, durable organopolysiloxane coating and process for producing same | |
| US4863802A (en) | UV-stabilized coatings | |
| US4218508A (en) | Polycarbonate articles coated with an adherent, durable silica filled organopolysiloxane coating and process for producing same | |
| GB2066101A (en) | Abrasion resistant silicone coated polycarbonate article | |
| GB2089826A (en) | Abrasion resistant ultraviolet light curable hard coating compositions | |
| JPH055865B2 (en) | ||
| CA1224182A (en) | Abrasion resistant ultraviolet light curable hard coating compositions | |
| US4243720A (en) | Silicone coated abrasion resistant polycarbonate article | |
| US4313979A (en) | Method for improving adhesion of silicone resin coating composition | |
| JP2002167552A (en) | Hard coating material composition and hard coat material | |
| US4298632A (en) | Silicone coated abrasion resistant polycarbonate article | |
| NL7903333A (en) | POLYCARBONATE PRODUCTS COATED WITH AN ADHESIVE SUSTAINABLE SILICON OXIDE AS A FILLER ORGANOPOLYSILOXANE LAYER AND METHOD OF MANUFACTURE HEREBY. | |
| CA1138590A (en) | Polycarbonate articles coated with an adherent organopolysiloxane | |
| NL7903334A (en) | POLYCARBONATE PREPARATIONS COATED WITH AN ADHESIVE, SUSTAINABLE SILICON OXIDE AS A FILLER ORGANOPOLYSILOXANE LAYER, AND METHOD OF MANUFACTURING THE SAME. | |
| JPS6352667B2 (en) | ||
| CA1162448A (en) | Abrasion resistant silicone coated polycarbonate article |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |