CH628673A5 - Curable coating composition - Google Patents

Description

The invention has for its object to provide a curable coating composition that is easy to process, in particular requires no hydrolysis, can be cured at moderately elevated temperatures, provides coatings with good resistance to corrosion and solvents that

5

10th

15

20th

25th

30th

35

40

45

50

55

60

65

3rd

628 673

give sensitive, soft base materials good abrasion resistance and have a low surface energy so that foreign particles do not adhere easily. The curable coating compositions according to the invention should be able to be applied to any soft, easily damaged surfaces, including plastics, natural materials, metals, ceramics and glass.

The object was achieved by a curable coating composition, which is characterized in that it contains the following components in a mixture with one another:

a) a compound of titanium, aluminum or zirconium of the formula

R'nM (OR) m ^ n wherein

M titanium, aluminum or zircon,

R is an alkyl or acyl group with 1 to 18 carbon atoms and

R 'is a ligand which is not RO- with the abovementioned meaning of R,

m represents the valence of M,

n has the value 0.1 or 2 and m-n has at least the value 2; and b) an ambifunctional silane of the formula

R1

n-Si-R2

are generally preferred because of their easy availability and advantageous properties. R is preferably an alkyl or acyl radical having 1 to 8 carbon atoms.

s It is critical that the metal compound is not fully hydrolyzed or hydrolyzed to the extent that there are fewer than two ester groups per metal atom on the metal compound. If it is largely hydrolyzed in this way, the ambifunctional silane and the metal compound precipitate together in an insoluble form because the reactive sites for the silane are missing from the compound.

Components (a) of the coating composition should preferably not be hydrolyzed. Although partially hydrolyzed components can also be used, the proportion of water present in the coating material may not be greater than 0.5 equivalent per equivalent of metal compound. For example, a larger proportion of water in compositions containing titanium alkoxide leads to the formation of titanium dioxide, which easily precipitates out of the mixture. The use of hy-20 drolyzed components has the further disadvantage that an additional step in the production of the coating composition is necessary. Furthermore, hydrolyzed components do not have the required durability.

In the silane compounds of the formula

R1- n'Si -R2 4_ n.

wherein

R1 for the group of the formula CH2 = CH-, for group 30 R1 is preferably the group of the formula of the formula

CH-, = C-C-O-R3-,

I II R40

CH, = C-C-O-R3

R40

35

wherein

R3 is an alkylene radical with 1 to 8 C atoms and R4 is hydrogen or a hydrocarbon radical with 1-8 C atoms or for the group of the formula

0 40

O

CH2 ^ CH-CR5) ^. or

(R5) n where

R5 is a divalent hydrocarbon radical with less than 20 carbon atoms or a divalent radical with less than 20 carbon atoms, the two free valences of which emanate from carbon, and the one carbon skeleton which is linked by 50 one or more heteroatoms which combine the carbon atoms and consist of nitrogen, sulfur and Ether oxygen is selected, is interrupted, has and is free from directly bonded heteroatoms and from atoms other than carbon, hydrogen, nitrogen, sulfur and 55 ether oxygen atoms, and m 'has the value 0 or 1, stands,

n 'is 1 or 2 and

R2 means a radical whose free valence starts from an oxygen bound to carbon. 60

In the metal compounds to be used in the coating composition according to the invention, all metal valences are preferably saturated by ester groups, but other groups can also be present as long as at least two ester groups are present. Metal compounds of the following 65 formula

M (OR) m

In the epoxy groups mentioned above, R5 is a divalent hydrocarbon radical with less than 20 carbon atoms, preferably an aliphatic, aromatic or aliphatic-aromatic hydrocarbon radical,

or then a divalent radical with less than 20 carbon atoms, the two free valences of which emanate from carbon and which has a carbon skeleton which is interrupted by one or more heteroatoms which connect the carbon atoms and are selected from nitrogen, sulfur and ether oxygen, and is free from hetero atoms bonded directly to one another and from atoms other than carbon, hydrogen, nitrogen, sulfur and ether oxygen atoms. R2 denotes a radical whose free valence originates from an oxygen atom bound to carbon, preferably an alkoxy or acyloxy radical having 1 to 8 carbon atoms, or R2 can also be a radical of the formula -0 (CH2CH20) k, in which Z is an aliphatic coal water -solid residue with less than 10 carbon atoms or a hydrogen atom and k is an integer with a value of at least 1. The radical R2 is a hydrocarbon radical optionally containing a nitrogen, sulfur or oxygen atom in the skeleton chain per 2 carbon atoms in the skeleton chain, in which a hydrogen atom bonded to a carbon has been replaced by a divalent oxygen atom, which therefore still has a free valence. Such a radical R2 can have the formula -0-CH2CH20CH3.

Specific examples of the skeleton chains of the radical R2 are the hydrocarbon radicals, such as aromatic radicals, e.g. the phenyl, naphthyl and benzothienyl group, and aliphatic linear, branched or cyclic radicals, including the cy-clohexyl, tetrahydrofuryl, dioxanyl, piperidyl, pyrrolidinyl and ethoxy-ethoxyethyl group. These R 2 radicals preferably contain 1 to 10 carbon atoms.

628 673

Specific examples of silanes which can be used are vinyltri-ethoxysilane, vinyltris (2-methoxyethoxy) silane, vinyltriacetoxysilane, Y-methacryloxypropyltrimethoxysilane, β- (3,4-epoxy-cyclohexyl) ethyltrimethoxysilane and Y-glycidoxysilane. The silanes can also be used in a mixture. Furthermore, it is also preferably possible to use compounds which are co-condensable or copolymerizable with the functional groups of component (b).

The molar ratio of metal compound to the reactive silanes usually depends on the composition of the coating composition. When using titanium alkoxides and epoxysilanes, the molar ratio is generally 2: 1 to 1: 7, preferably 1: 4. When using titanium alkoxides and acryloyloxysilane, the molar ratio is usually 1: 3 5 to 1:15, preferably 1: 3 to 1: 7 and in particular about 1: 4. When using titanium alkoxides and vinyl silanes, the most favorable molar ratio is approximately 1: 4. Further possible molar ratios of metal compound to reactive silanes are summarized in Table 1.

Table 1

curable coating material

Al aloxide

Epoxysilane

Al alkoxide

Acryloyloxysilane

Zr alkoxide

Epoxysilane

Zr alkoxide

Acryloyloxysilane

Molar ratio metal compound: reactive silane wide range

1: 1 to 1: 5 1: 1 to 1:10 1: 3.5 to 1: 4.5 1: 3.5 to 1: 4.5

preferred area

1: 2 to 1: 5 1: 2 to 1: 5 1: 4 1: 4

more preferred

Area

1: 4

1: 4

1: 4

1: 4

The coating compositions according to the invention can also contain conventional additives and / or auxiliaries, for example 30 pigments or dyes, solvents (for component a), furthermore solvents or other viscosity regulators and leveling agents.

Curing accelerators, fillers and polymeric modifiers can also be incorporated into the coating composition.

To reduce the viscosity of the coating composition, solvents can be added, such as lower alcohols, lower carboxylic acids, halogenated hydrocarbons or aromatic hydrocarbons, such as ethanol, methanol, tert-40 butanol, chloroform, methylene chloride, acetic acid, toluene, benzene, xylene, trichloroethane and 1,2-dichloroethane. The amount of solvent added normally depends on the metal compound used and the viscosity of the coating composition. «

To increase the viscosity of the coating composition, oligomerized silanes can be added in an amount of 1 to 20 percent by weight, based on the coating composition. For example, y-methacryloxypropyl-trimeth-oxysilane, which was previously polymerized for 20 minutes at 100 ° C. via a free radical mechanism and then diluted to a 50% solution in ethanol, increases the viscosity of the coating composition.

Equalization agents can also be used with advantage. Specific examples of leveling agents that can be used are the silicone-based surfactant from General Electric “SF-1023” and the fluorocarbon-based surfactants from Minnesota Mining and Manufacturing Co. “FC-430” and “FC-431”. These leveling agents are preferably added in an amount of approximately 0.3 percent by weight, based on the coating mass. However, larger or smaller amounts can also be added. A preferred leveling agent is «SF-1023».

Generally, the coating composition is filtered through a 10 micron filter after it is made. 65

The curable coating composition according to the invention can be applied to a large number of substrates or base materials in order to impart abrasion resistance, solvent resistance and corrosion resistance. In general, both rigid and flexible substrates can be coated, for example molded parts made of plastic, glass, metals or ceramics. Soft base materials, such as plastics, can be made scratch and abrasion resistant. Examples of this are lenses for glasses, sunglasses, optical instruments, lamps, watch crystals, plastic discs, signs and decorative surfaces. Metal surfaces can be made corrosion-resistant, while the gloss on decorative metal strips and the surface of mirrors can be retained. Furthermore, the coating material can be colored and applied to surfaces as a paint.

Those base materials to which the coating composition according to the invention does not show good natural adhesion can nevertheless be coated well if their surface is first pretreated, for example by roughening the surface (mechanically, by solvent, by chemical etching, oxidation, etc.) and applying one Primer.

The curable coating composition can be applied to the substrate in any desired thickness. Coatings of 3 to 5 microns thick provide excellent abrasion resistance. However, thicker coatings (up to 20 microns and more) can be obtained by applying multiple layers on the substrate. This can be achieved by first applying a layer of the coating composition to the substrate and then partially curing it, for example by heating to about 75 ° C. for 1 minute. A second layer can then be applied. This process can be repeated until the desired thickness of the coating is reached. These multiple coatings show a much higher abrasion resistance than a single coating.

The coating can be cured by various methods, for example by heat, ultraviolet light or electron beams. The method to be used depends in the standard on the coating composition and the substrate to be coated.

All curable coating compositions described here can be cured by exposure to heat. From-

5

628 673

Hardening time and temperature generally depends on the type of force being controlled by the weights 28 which depend on a rod of the coating composition. For example, the vinyl 30 need to be put on and supported by a ring 32. The and acryloyloxysilane metal compound coating compositions rod 30 is connected to the grinding block 24. The weights

Curing times of 30 to 60 minutes at temperatures 28 are achieved with the help of a bearing 34 directly above the grinding

from 130 ° C to 170 ° C, preferably at about 150 ° C. In contrast, 5 block 24 held by arms 36. Bearing 34 allows epoxy silane metal compound coatings to move freely vertically while allowing horizontal

at temperatures of 75 ° C to 100 ° C within about 16 le movement of the grinding block 24 prevented.

can be cured up to 40 hours. The abrasion resistance is measured by using a

curing temperature generally shortens the curing time. layered substrate 18 as described above on the

The hardening time of the coating composition is fixed to the top of the shaking plate 14, the abrasive 20

named temperatures can be pressed against the coated surface 22 by adding a small amount and a previously accelerator can be significantly reduced. Use the weights 28 to apply the specified grinding force. Then accelerators are preferably set in an amount of approximately the shaker plate 14 in motion. The number

0.4 to 2.5 percent by weight, based on the coating of complete oscillating movements, is calculated using a counter 38

mass, used. Specific examples of usable 15 counted. After 100 cycles (1 cycle includes a full accelerator, mineral acids such as hydrochloric acid, nitric acid forward and backward movement) the vibrating or sulfuric acid, further Lewis acids such as boron trifluoride and shaking plate are stopped and the surface 22 of the coated

Aluminum trichloride. Visually examined substrate 18 for scratches. The weights 28

All coating compositions which contain titanium alkoxide are then either increased or decreased in stages, and are preferably cured by irradiation with ultraviolet light 20. The process is cured using a new, non-ground test. The radiation should preferably be repeated under a sample.

Shielding gas, such as nitrogen, carbon dioxide, helium or argon, the maximum weight (including grinding block 24, rod can be carried out since oxygen inhibits curing. 30, ring 32 and weights 28), which the abrasive 20

The time required for the coatings to cure changes can be set without visible scratches on the test sample, generally inversely related to the intensity of the light. 25 causing after 100 cycles is recorded. The value

For example, the irradiation with light of a 275 watt for the abrasion resistance can be specified in g / cm2. The

UV lamp through a quartz glass filter into a nitrogen-bonded strength of the hardened coating on the substrate, the chamber which contains the coated substrate is generally determined as follows:

leads. The quartz glass filter is permeable to ultraviolet. With a sharp blade, light is shone into the coated surface in the range of approximately 2000 to 4000 Â. Replacing a series of parallel incisions, which may harden approximately 0.318 cm, may be within 5 to 20 minutes depending on the spacing, and another similar series of removal of the light source from the substrate. cut at right angles to it, which are also about 0.318 cm vinyl and acryloyloxysilane metal compound coating apart. Around 50 squares can be cut into the masses by irradiation with an electrode beam-hardened coating. Harden a piece of «Scotch» oil. Here, too, the irradiation is preferably carried out 35 Brand Magic Transparent Band No. 810 is firmly pressed onto the protective gas, such as nitrogen, carbon dioxide, helium or layered surface, so that the whole cruciform argon is carried out. The area cut to harden the coating is covered. The tape is then changed under the necessary time, usually reversely to the angle of 90 °, quickly pulled off the substrate by hand. Strength of the electron beam source. The radiation can be - The adhesive strength is given in values from 0 to 100%. be carried out, for example, in such a way that the coated substrate 40 is passed through a chamber flushed with an inert gas for each square removed during the test, the value for the adhesive strength reduced by 2%.

to which an electron beam is directed. The following examples illustrate the invention. Parts and source can e.g. the model CB-150 Electro-Curtain from the company percentages relate to the weight, if nothing

Energy Sciences, Incorporated, Burlington, Massachusetts. other is indicated.

The coatings can be removed within 4 seconds

be hardened. example 1

The abrasion resistance of the tetraisopropyl titanate and y-methacryloxypropyltrimeth-

The coating obtained can be mixed by the oxysilane in a molar ratio of 1:10 and at

Vibration abrasion test can be demonstrated. This test stirred room temperature. The coating compound is applied on a

is carried out using the device shown in FIG. 1 and made of polydiallyl glycol carbonate and by irradiation. cured with ultraviolet light for 15 minutes.

The device 10 consists of a shaking plate 14 in. The 3 to 5 micron thick coating is smooth, clear, transparent.

a housing 12. The shaking plate 14 is parent with a motor, firmly bonded to the substrate and resistant to abrasion.

which swings them back and forth over an arm 16 The experiment is carried out with a molar ratio of the components

drives. This device is repeated by the company Eberbach Corpoten 55: 1: 4 with comparable results.

ration available as model 6000. The shaking plate 14

vibrates at a frequency of 1.25 U / sec. and a hub Examples 2 to 8

of 3.75 cm. Aluminum isopropoxide (0.1 mol) is melted

A coated substrate 18 to be examined is heated at the point (117 to 120 ° C.) and dissolved in 80 g of toluene at the top of the shaking plate 14 at a temperature of 80 ° C. The dissolution takes V2 hour attached to a double coated strip. An abrasive and the solution is filtered through Whatman # 12 filter paper against the coated surface 22 of the substrate 18. The solution is then pressed with y-glycidoxypropyltrimetho and attached to the bottom of a grinding block 24 with the aid of a xysilane in the molar ratio given in Table II, double-coated strip. The abrasive 20 mixes on 5 x 5 x 0.16 cm polydiallylgly plates made of steel wool No. 3/0. The bottom 26 of the sanding block 65 is applied in carbonate and cured at 85 ° C. for 16 hours. 24 cm 2.5 cm x 2.5 cm and the area of the abrasive 20, the coatings obtained (3 to 5 microns) are clear, even, which is in pressure contact with the surface 22, transparent and abrasion-resistant.

therefore carries about 2.5 cm X 2.5 cm. The desired abrasion results are summarized in Table II.

628 673

6

Table II example

Molar ratio of metal alkoxide: reactive silane abrasion resistance, g / cm2

5 6 7

1: 1 1: 2 1: 3

704 1056 1408

Table III Example

Molar ratio of metal alkoxide: reactive silane

Abrasion resistance, kg, g / cm

Half strength,%

Examples 9 to 18

8 Aluminum isopropoxide is described in

Toluene dissolved and mixed with y-methacryloxypropyltrimethoxysilane. The mixture is applied to plates made of polydiallyl glycol car bonate and cured in an oven for 60 minutes at 150 ° C. 1: 4 1: 5 1: 7 1:10. All coatings are clear, flat and transparent. The results are summarized in Table III.

1760 1408 352 0

9 10 11 12 13 14 15 15 16 17 18

1: 1 1: 2 1: 3 1: 4 1: 5 1: 7 1:10 1:15 1:20 1:30

845 2112 1197 1760 845 1056 845 704 704 493

100 100 100 100 100 100 100 100 100 100

Example 19

A 5 cm x 5 cm x 0.64 cm plate made of a polycarbonate made from bisphenol A and phosgene ("Lexan") is washed with anhydrous ethanol and then dried with a fiber-free cloth. A coating composition of the following composition is then applied:

Tetraisopropyl titanate 2 g

Y-glycidoxypropyltrimethoxysilane 3 g y-methacryloxypropyltrimethoxysilane 3 g conc. Hydrochloric acid 4 drops

"SF-1023" 1 drop

(Leveling agent based on silicone)

The plate is placed in an oven at 150 ° C for 15 minutes.

t is heating. The coated plate is used for complete curing

35

placed in a nitrogen purged chamber and irradiated with ultraviolet light. The hardened coating (about 3 to 5 microns thick) is clear, flat, transparent, firmly bonded to the substrate and very abrasion-resistant.

Examples 20 to 29 Coating compositions are prepared from tetraisopropyl titanate and y-methacryloxypropyltrimethoxysilane in various molar ratios in beakers at room temperature. The coating compositions obtained are then applied to the plastic plates used in Example 19 and cured. The cured coatings (about 3 to 5 microns thick) are clear, flat, transparent and firmly bonded to the substrate. They are very resistant to solvents and corrosion. The results are summarized in Table IV.

Table IV example

Molar ratio of metal alkoxide: reactive silane

Abrasion resistance, g / cm2

Adhesion strength,%

20th

1: 1

140

100

212223242526272829 1: 2 1: 3 1: 4 1: 5 1: 7 1:10 1:15 1:20 1:30

211 1056 2112 1760 1056 985 704 633 211 100 100 100 100 100 100 100 100 100

Examples 30 to 38 Coating compositions are prepared from tetraisopropyl titanate and v-glyidoxypropyltrimethoxysilane in various molar ratios in beakers at room temperature. The coating compositions obtained are applied to plates made of polydiallyl glycol carbonate and according to Example 1

Irradiated with UV light for approximately 7.5 cm in minutes. The curing is then completed by heating to 85 ° C. for 16 hours. The coatings have properties similar to the coatings mentioned above. The results are summarized in Table V.

7

628 673

Table V example

Molar ratio of metal alkoxide: reactive silane

30th

1: 0.5

31 32 33 34 35 36 37 38

1: 1.5 1: 4 1: 5 1: 6 1:10 1:15 1:20 1:30

Abrasion resistance, g / cm2

Adhesion strength,%

2253

100

Comparative Examples A and B 15

Substrates coated with commercially available coating compositions were examined for their abrasion resistance with the aid of the vibrating abrasion device. The results are summarized in Table VI.

Table VI 20

Comparative example coating composition

General Electric

"MR-4000",

Melamine resin

B

du Pont «Abcite» silicone fluorocarbon resin

Substrate

Abrasion resistance, g / cm2

Polycarbonate made from polymethyl bisphenol A and meth phosgene ("Lexan") acrylate

140

704

30th

35

Example 39

A 5 cm X 5 cm X 0.16 cm sheet of polydiallyl glycol carbonate is washed with anhydrous ethanol and dried with a lint-free cloth. A coating composition of the composition given below is prepared in a beaker at room temperature and applied to the substrate.

Tetraisopropyl titanate y-glycidoxypropyltrimethoxysilane borotrifluoride ether complex silicone leveling agent (SF1023)

1.75 g 6.0 g

4.0 drops 45 1.0 drops

The coated substrate is brought into a chamber flushed with nitrogen and, according to Example 14, irradiated with UV 50 light at a distance of 7.5 cm. The curing is then completed by heating to 85 ° C. for 8 hours. The coating obtained (about 3 to 5 microns thick) is clear, transparent and firmly bonded to the substrate. The coating is also very abrasion-resistant (it shows an abrasion resistance of 1760 g / cm2), very solvent-resistant and very corrosion-resistant.

Example 40

33 g of zirconium isopropoxide are dissolved in 167 g of toluene at 75 ° C 60. The warm solution is filtered using a Buchner funnel and Whatman # 1 filter paper.

A 5 cm X 5 cm X 0.16 cm sheet of polydiallyl glycol carbonate is washed with anhydrous ethanol and dried with a lint-free cloth. A coating composition of the composition given below is prepared in a beaker at room temperature and applied to the substrate.

2253 2464 1408 1267 281 422 211 140

100 100 100 100 100 100 100 100

Zirconium isopropoxide toluene solution 12.0 g y-methacryloxypropyltrimethoxysilane 6.0 g

Leveling agent based on silicone (SF 1023) 1.0 drops

The coated substrate is cured at 140 ° C for 60 minutes. The coating obtained (about 3 to 5 microns thick) is clear, flat, transparent and firmly bonded to the substrate. The coating is also abrasion-resistant (it shows an abrasion resistance of 845 g / cm2), very solvent-resistant and very corrosion-resistant.

Example 41

A 5 cm X 5 cm X 0.16 cm sheet of polymethyl methacrylate is washed with anhydrous ethanol and dried with a lint-free cloth. A coating composition of the composition given below is prepared in a beaker at room temperature and applied to the substrate.

Tetraisopropyl titanate

Vinyl tris (2-methoxyethoxy) silane

(«A-172»)

1.75 g 7.0 g

The coated substrate is passed through a chamber which is purged with nitrogen. An electron beam is radiated into this chamber. The electron source is operated at 10 mil liampère and 150 kV. The coated substrate is exposed to the electron beam for 4 seconds. The coating obtained (about 3 to 5 microns thick) is clear, flat, transparent and firmly bonded to the substrate. The coating is also abrasion-resistant (it has an abrasion resistance of 704 to 845 g / m2), very solvent-resistant and very corrosion-resistant.

Example 42

A coating composition is made using partially hydrolyzed tetraisopropyl titanate. The tetraisopropyl titanate is hydrolyzed as follows:

a) 4.7 g of 37 percent (concentrated) hydrochloric acid are mixed with 67 g of anhydrous ethanol;

b) 28.4 g (0.1 mol) of tetraisopropyl titanate are added to solution (a).

The hydrolysis is carried out at room temperature for about 15 minutes. The following ingredients are then mixed together at room temperature:

Hydrolyzed tetraisopropyl titanate solution 5.0 g y-methacryloxypropyltrimethoxysilane 6.0 g

Leveling agent based on silicone (SF 1023) 0.26 g

Example 43

A 5 cm x 7 cm x 0.16 cm aluminum plate is cleaned with an abrasive pad and water, washed with anhydrous ethanol and dried with a lint-free cloth. The coating composition of Example 42 is applied to the surface of the aluminum plate and cured at 150 ° C. for 60 minutes. The coating obtained

628 673

8th

(about 3 to 5 microns thick) is clear, flat, transparent, abrasion-resistant and firmly bonded to the substrate.

Example 44

Polyester plates are etched with a dilute solution of 5 sulfuric acid in anhydrous ethanol. The coating composition from Example 42 is applied to the etched-on polyester plates and cured at 150 ° C. for 60 minutes. The coatings obtained (about 3 to 5 microns thick) are clear, flat, transparent, abrasion-resistant and firmly bonded to the substrate, OK

Example 45

Plates made of an acrylic polymer are pretreated by a) immersion in chloroform for 2 minutes, 15

b) immersion in dichloromethane (30 seconds at 25 ° C),

c) roughening the surface with fine sandpaper,

d) roughening the surface with aluminum oxide grinding powder and then in each case coated with the coating material from Example 42 and cured at 150 ° C. for 60 minutes. 20th

The coatings obtained (about 3 to 5 microns thick)

are clear, even, transparent, abrasion-resistant, solvent-resistant and firmly bonded to the substrate.

is primed with a solution of amidated and epoxidized poly-butadiene in methanol. Then a coating composition of the following composition

Example 46 25

A 5 cm X 5 cm X 0.16 cm plate made of polydiallyl glycol carbonate is washed with anhydrous ethanol and dried with a fiber-free cloth. A coating composition of the following composition

30th

Tetraisopropyl titanate 2 g y-methacryloxypropyltrimethoxysilane 6 g

Leveling agent based on silicone 1 drop is then applied to the plate and cured according to Example 41-35 within about 8 seconds. The coating obtained (about 3 to 5 microns thick) is clear, flat, transparent, resistant to abrasion and solvents and is firmly bonded to the substrate.

Tetraisopropyl titanate 2.0 g

Y-glycidoxypropyltrimethoxysilane 6.0 g

Leveling agent based on silicone 1.0 drops

(SF 1023)

applied to the plate and partially hardened for 1 minute at 75 ° C. The coated plate is cooled to room temperature (25 ° C.) and provided with a second layer of the coating composition. The coating is cured at 75 ° C for 16 hours.

The coating (about 8 microns thick) is clear, flat, flexible, transparent and is firmly bonded to the substrate. The coating is also abrasion-resistant (it shows an abrasion resistance of 1408 g / cm2), very solvent-resistant and very corrosion-resistant.

Examples 49 to 52 These examples illustrate the use of various metal alkoxides containing at least two alkoxy groups per metal atom. 36 g of Y-glycidoxypropyltrimethoxysilane are divided into 3 parts A, B and C. Part A is mixed with 5.0 g of bis-diethanolamino-bis-isopropoxytitanate

[(OHCH2CH2) 2N] 2 Ti (OC3H7) 2,

Part B with 8.5 g of dichlorodibutoxytitanate solution Cl2Ti (0 (CH2) 3CH3) 2 and part C with 8.0 g of chlorodibutoxyaluminate solution

40

Example 47

A coating composition of tetraisopropyl titanate and γ-methacrylicoxypropyltrimethoxysilane in a molar ratio of 1: 4 is applied to a plate made of the polycarbonate according to Example 19 and heated to 150 ° C. for 20 minutes, and then 45 minutes with UV light at a distance of irradiated approximately 7.5 cm.

The solvent resistance of the cured coating is determined as follows: Four or five small pools of solvent are applied to the surface of the plate for 50 and left to act for about 20 minutes. The puddles are then wiped dry and the surface of the coating is visually examined for damage. It has been found that the coating is not attacked by the following solvents: 55

a) water b) ethanol c) methanol d) acetone e) 2-butanone f) chloroform g) dimethylformamide h) conc. Hydrochloric acid i) toluene

60

Example 48

A 10 cm X 10 cm X 0.13 cm sheet made of polyester

CIA1 (0 (CH2) 3CH3) 2 added.

The metal compounds of B and C are added as solutions in methylene chloride with a solids content of 25 percent by weight. 2 drops of an oligomeric leveling agent based on fluorocarbon are added as a coating aid.

The coating solution D is made up of 6.0 g -glycidoxypropyltrimethoxysilane and 4.5 g of a polymeric titanate with basic building blocks of the formula o- (CH2) 3CH3 [Ti ^ -0] x

0- (CH2) 3CH3

prepared and mixed with a drop of SF 1023 (leveling agent).

Polydiallyl glycol carbonate plates (about 7.7 X 7.7 X 0.16 cm) are washed with anhydrous ethanol and dried with a lint-free cloth. The coating solutions are applied to the plates and cured in an oven at 85 ° C for 16 hours.

The coatings obtained are in all cases flat, transparent, solvent-resistant and have very good abrasion resistance compared to steel wool No. 3/0.

1 sheet of drawings

Claims (10)

628 673 2. Coating composition according to claim 1, characterized in that R 'is hydrogen, halogen or Q-Cg-alkyl. 2nd PATENT CLAIMS 1. Curable coating composition, characterized in that it contains the following components in a mixture with one another: a) a compound of titanium, aluminum or zirconium of the formula r'nm (or) m. " wherein M titanium, aluminum or zircon, R is an alkyl or acyl group with 1 to 18 carbon atoms and R 'is a ligand that is not RO- with the abovementioned meaning of R, m represents the valence of M n has the value 0.1 or 2 and m-n has at least the value 2; and b) an ambifunctional silane of the formula [R '-] nSi [-R2] 4_n. wherein R1 for the group of the formula CH2 = CH—, for the group of the formula ch2 = c-c-o-r3-, I II r4 o where R3 is an alkylene radical with 1 to 8 C atoms and R4 is hydrogen or a hydrocarbon radical with 1-8 C atoms, or for the group of the formula / \, CH2 - CH - (R) m-, or wherein R5 is a divalent hydrocarbon radical with less than 20 carbon atoms or a divalent radical with less than 20 carbon atoms, the two free valences of which emanate from carbon, and the one carbon skeleton which is joined by one or more heteroatoms and which consists of nitrogen, sulfur and Ether oxygen is selected, is interrupted, has and is free of directly bonded heteroatoms and of atoms other than carbon, hydrogen, nitrogen, sulfur and ether oxygen atoms, and m 'has the value 0 or 1 , n 'is 1 or 2 and R2 represents a radical whose free valence starts from an oxygen atom bound to carbon. 3. Coating composition according to claim 1, characterized in that it as component b) is one of the formula O / \ CH.-CH-rR'j ,, 'Si (—OR ") .- 4. Coating composition according to claim 3, characterized in that the metal compound has the formula Ti (OR) 4, in which R is an alkyl or acyl radical having 1 to 18 carbon atoms, and the molar ratio of metal compound to epoxysilane 2: 1 to Is 1: 7. 4 m contains, where n "is 0 or 1, m "means 2 or 3 and R "is a hydrocarbon radical having 1-18 carbon atoms or a radical of the formula - (CH2CH20) concentration camp where k is an integer with a value of at least 1 and Z represents a hydrogen atom or an aliphatic hydrocarbon radical having less than 10 carbon atoms. 4 m or 5. Coating composition according to claim 3, characterized in that the metal compound has the formula Al (OR) 3, in which R is an alkyl or acyl radical having 1 to 18 carbon atoms, and the molar ratio of metal compound to epoxysilane 1: 1 to 1: 5 is. 6. Coating composition according to claim 3, characterized in that the metal compound has the formula Zr (OR) 4, in which R is an alkyl or acyl radical having 1 to 18 carbon atoms, and the molar ratio of metal compound to epoxysilane 1: 1 to 1: 4 is. 7. Coating composition according to claim 1, characterized in that the metal compound is tetraisopropyl titanate, t-trabutyl titanate, tetra-2-ethylhexyl titanate, tetraethyl titanate, aluminum isopropoxide, aluminum n-butoxide or tetraisopropyl zirconate. 8. Coating composition according to claim 1, characterized by an additional content of a compound which is co-condensable or copolymerizable with component b). 9. Use of the coating composition according to claim 1 for the production of abrasion-resistant surfaces of base materials by applying the coating composition to the surface of the base material and curing the paint film by irradiation with UV light and / or electron beams and / or by heat. 10. Use according to claim 9, characterized in that the coating composition is applied to a surface which is pretreated with a primer. It is often necessary to protect sensitive surfaces from abrasion by coating them with a protective coating. Numerous publications are known in the field of anti-abrasion protective coatings; see. U.S. Patents 3,687,882.3,637,416.3,642,681.3 708 225.3 460,956, 3,762,981 and 2,768,909; and JA-PS r. 49-117529.