Coating material and process for the production of functional coatings

• US 6,534,187 B2
• Filed: 04/27/2001
• Issued: 03/18/2003
• Est. Priority Date: 02/08/1993
• Status: Expired due to Fees

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: Greiwe, Klaus, Kron, Johanna, Schottner, Gerhard
• Primary Examiner(s): Moore, Margaret G.
• Assistant Examiner(s): Peng, Kuo Liang
• Application Number:
  US09/843,628
• Publication Number:
  US 20020018900A1
• Time in Patent Office: 690 Days
• Field of Search: 528/33, 528/25, 528/12, 524/430, 106/287.16, 106/287.12, 106/287.17, 525/474, 428/447, 427/493
• US Class Current: 428/447
• CPC Class Codes: C03C 17/009 Mixtures of organic and inorganic materials, e.g. ormosils and ormocers
• CPC Class Codes: C03C 17/30 with silicon-containing compounds
• CPC Class Codes: C08L 2666/14 Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
• CPC Class Codes: C09D 183/14 in which at least two but not all the silicon atoms are connected by linkages other than oxygen atoms C09D183/10 takes precedence
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

The invention relates to a process for producing functional coatings with organofunctional silanes, a metal compound and difficultly volatile oxides, in which

a) a hydrolytic condensation is performed, optionally in the presence of a condensation catalyst and/or additives, of the following components

1. at least one crosslinkable organofunctional silane,

2. at least one metal compound,

3. optionally at least one non-crosslinkable organofunctional silane and

4. optionally one or more difficultly volatile oxides soluble in the reaction medium;

b) that to said hydrolytic condensate is added an organic, crosslinkable prepolymer; and

c) the thus obtained coating solution is applied to a substrate and subsequently cured.

Claims

1. Process for the production of abrasion resistant functional coatings utilizing organofunctional silanes, a metal compound and difficultly volatile oxides, comprising the steps of:

a) performing a hydrolytic condensation, optionally in the presence of a condensation catalyst and/or additives, of the following components

1) at least one crosslinkable, organofunctional silane of formula (II)

2. Process according to claim 1, characterized in that the metal compound of general formula III (component 2) is added in chelated form.

3. Production process according to claim 1, characterized in that in place of process stages a) and b), there is initially a hydrolytic precondensation with a smaller water quantity than is stoichiometrically necessary for the complete hydrolysis of the hydrolyzable groups, then the prepolymer is added and this is followed by further condensation by adding further water, which wholly or partly brings about the hydrolysis of the remaining hydrolyzable groups and optionally a condensation catalyst.

4. Process according to claim 1, characterized in that, based on the total number of moles of the starting components, 2 to 90 mole % component 1, 5 to 60 mole % of component 2, 0 to 50 mole % of component 3 and 0 to 40 mole % of component 4 are used.

5. Process according to claim 1, characterized in that the hydrolytic condensation or the further condensation takes place in the presence of an acid or basic condensation catalyst.

6. Process according to claim 3, characterized in that the water quantity used for precondensation is introduced by means of moisture-containing adsorbents, water-containing organic solvents, salt hydrates or water-forming systems.

7. Process according to claim 1, characterized in that the additives are chosen from organic thinners, flow-control agents, colouring agents, UV-stabilizers, fillers, viscosity regulators, lubricants, spreading agents, sedimentation inhibitors or oxidation inhibitors or mixtures thereof.

8. Process according to claim 1, characterized in that, prior to the application of the coating material, the substrate surface is treated with a primer, heated, leached out, precleaned by means of aqueous or organic media and/or exposed to an electric discharge.

9. Process according to claim 1, characterized in that the coating is hardened by heat treatment at a temperature up to 200°

C., and/or by treatment with rays.

10. Process according to claim 1, characterized in that the hardened coating undergoes chemical and/or physical aftertreatment.

18. Process according to claim 1 characterized in that the coating is hardened by heat treatment at a temperature in the range of about 60 to 160°

C., and/or treatment with rays.

19. Process according to claim 1, characterized in that, based on the total number of moles of the starting components, 30 to 90 mole % of component 1, 10 to 40 mole % of component 2, 0 to 40 mole % of component 3 and 0 to 40 mole % of component 4 are used.

11. A coating material for producing coatings on substrates, characterized in that it is obtained by hydrolytic condensation, said coating material comprising:

1) at least one crosslinkable, organofunctional silane of formula (II)

12. A coating material according to claim 11, characterized in that the metal compound of general formula III (component 2) is added in chelated form.

13. A coating material according to claim 12, characterized in that for producing the hydrolytic condensate, firstly there is a hydrolytic precondensation of components 1 to 4 with a smaller water quantity than is stoichiometrically necessary for the complete hydrolysis of the hydrolyzable groups, the prepolymer is then added, followed by further condensation by adding further water, which brings about the partial or complete hydrolysis of the remaining hydrolyzable groups, as well as optionally a condensation catalyst.

15. A coating material according to claim 12, further comprises additives chosen from organic thinners, flow-control agents, coloring agents, UV-stabilizers, fillers, viscosity regulators, lubricants, spreading agents, sedimentation inhibitors or oxidation inhibitors or mixtures thereof.

16. A coating material according to claim 12 further comprises a condensation catalyst selected form an acid or a basic condensation catalyst.

17. A coating material according to claim 12, characterized in that the viscosity is adjusted to 5 to 50 mPa·

s.

14. A scratch-proof coated substrate prepared by a process comprising the steps of:

a) performing a hydrolytic condensation, optionally in the presence of a condensation catalyst and/or additives, of the following components;

1) at least one crosslinkable, organofunctional silane of formula (II)