UV curable transparent conductive compositions

• US 6,784,223 B2
• Filed: 07/11/2002
• Issued: 08/31/2004
• Est. Priority Date: 01/13/2000
• Status: Expired due to Fees

• Current Assignee: UV Specialties, Inc.
• Original Assignee: Allied PhotoChemical, Inc.
• Inventors: Krohn, Roy C.
• Primary Examiner(s): Seidleck, James J.
• Assistant Examiner(s): McClendon, Sanza L.
• Application Number:
  US10/193,389
• Publication Number:
  US 20030045596A1
• Time in Patent Office: 782 Days
• Field of Search: 522/90, 522/92, 522/81, 522/96, 522/100, 522/109, 522/110, 522/113, 522/114, 522/120, 522/181, 427/508, 427/510, 427/512
• US Class Current: 522/92
• CPC Class Codes: C08F 220/1811 C10or C11-(Meth)acrylate, e.g. isodecyl (meth)acrylate, isobornyl (meth)acrylate or 2-naphthyl (meth)acrylate
• CPC Class Codes: C08F 290/06 Polymers provided for in subclass C08G
• CPC Class Codes: C08F 290/14 Polymers provided for in subclass C08G
• CPC Class Codes: C09D 4/00 Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16
• CPC Class Codes: C09D 4/06 Organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond in combination with a macromolecular compound other than an unsaturated polymer of groups C09D159/00 - C09D187/00
• CPC Class Codes: C09D 5/24 Electrically-conducting paints conductive materials H01B1/00

Abstract

The present invention discloses an ultraviolet light curable transparent conductive composition and method for making such a composition that may be used to produce a transparent conductive coating on a suitable substrate. These coatings may be used in such applications as touch screens, membrane switches, TV screens, and VCRs. The disclosed composition does not contain any significant amount of volatile organic solvents that do not become incorporated in the active layer after curing.

Claims

1. A photocurable transparent conductive composition comprising:

at least one aliphatic acrylated oligomer selected from an aliphatic urethane diacrylate or aliphatic urethane triacrylate;

an acrylated epoxy oligomer;

an isobornyl acrylate monomer;

an electrically conductive powder present in an amount from 20% to 50% of the weight of the transparent conductive composition; and

a photoinitiator,

wherein the photocurable transparent conductive composition is curable by ultraviolet light into a transparent conductive coating.

2. The photocurable transparent conductive composition of claim 1 wherein the electrically conductive powder a metal powders, a metal oxide powder, a metal nitride powder, or mixtures thereof.

3. The photocurable transparent conductive composition of claim 1 further comprising a flow promoting agent.

4. The photocurable transparent conductive composition of claim 3 wherein:

the aliphatic acrylated oligomer is 10% to 40% of the weight of the transparent conductive composition;

the acrylated epoxy oligomer is 3% to 11% of the weight of the transparent conductive composition;

the isobornyl acrylate monomer is 10% to 40% of the weight of the transparent conductive composition;

the photoinitiator is 2% to 10% of the weight of the transparent conductive composition; and

the flow promoting agent is 0.1% to 8% of the weight of the transparent conductive composition.

5. The photocurable transparent conductive composition of claim 3 wherein:

the aliphatic acrylated oligomer is 20% to 30% of the weight of the transparent conductive composition;

the acrylated epoxy oligomer is 5% to 9% of the weight of the transparent conductive composition;

the isobornyl acrylate monomer is 20% to 35% of the weight of the transparent conductive composition;

the photoinitiator is 4% to 6% of the weight of the transparent conductive composition;

the flow promoting agent is 3% to 5% of the weight of the transparent conductive composition; and

the electrically conductive powder is 30% to 40% of the weight of the transparent conductive composition.

6. The photocurable transparent conductive composition of claim 3 wherein:

the aliphatic acrylated oligomer is 27% of the weight of the transparent conductive composition;

the acrylated epoxy oligomer is 7% of the weight of the transparent conductive composition;

the isobornyl acrylate monomer is 28% of the weight of the transparent conductive composition;

the photoinitiator is 5% of the weight of the transparent conductive composition;

the flow promoting agent is 3.5% of the weight of the transparent conductive composition; and

the electrically conductive powder is 33% of the weight of the transparent conductive composition.

7. The transparent conductive composition of claim 1 wherein the isobornyl acrylate monomer is selected from the group consisting of isobornyl acrylate, isobornyl methacrylate, and mixtures thereof.

8. The transparent conductive composition of claim 1 wherein the photoinitiator is selected from the group consisting of:

1-hydroxycyclohexyl phenyl ketone;

2-methyl-1-[4-(methylthio)phenyl]-2-morpholino propan-1-one;

the combination of 50% 1-hydroxy cyclohexyl phenyl ketone and 50% benzophenone;

2,2-dimethoxy-1,2-diphenylethan-1-one;

the combination of 25% bis(2,6-dimethoxybenzoyl-2,4-, 4-trimethyl pentyl phosphine oxide and 75% 2-hydroxy-2-methyl-1-phenyl-propan-1-one;

2-hydroxy-2-methyl-1-phenyl-1-propane;

the combination of 50% 2,4,6-trimethylbenzoyldiphenyl-phosphine oxide and 50% 2-hydroxy 2-methyl-1-phenyl-propan-1-one;

mixed triaryl sulfonium hexafluoroantimonate salts, mixed triaryl sulfonium hexafluorophosphate salts; and

mixtures thereof.

9. The transparent conductive composition of claim 1 wherein the acrylated epoxy oligomer is selected from the group consisting of:

novolac epoxy acrylate diluted 20% by weight with tripropylene glycol diacrylate;

difunctional bisphenol based epoxy acrylate; and

mixtures thereof.

10. A method for coating a substrate with a photocurable transparent conductive composition, the method comprising:

applying a transparent conductive composition to the substrate, wherein the transparent conductive composition includes;

an aliphatic acrylated oligomer selected from an aliphatic urethane diacrylate or aliphatic urethane triacrylate present in an amount from 10% to 40% of the weight of the transparent conductive composition;

an acrylated epoxy oligomer present in an amount from 3% to 11% of the weight of the transparent conductive composition;

an isobornyl acrylate monomer present in an amount from 10% to 40% of the weight of the transparent conductive composition;

a photoinitiator present in an amount from 2% to 10% of the weight of the transparent conductive composition;

a flow promoting agent present in an amount from 0.1% to 8% of the weight of the transparent conductive composition; and

an electrically conductive powder present in an amount from 20% to 50% of the weight of the transparent conductive composition and

illuminating the transparent conductive composition with an UV light sufficient to cause the transparent conductive composition to cure into a transparent conductive coating.

11. The method of claim 10, wherein UV light used in illuminating impinges upon the transparent conductive composition so that the transparent conductive composition is caused to form a coating as it cures.

12. The method of claim 10, wherein the method of applying the transparent conductive composition is spraying.

13. The method of claim 10, wherein the method of applying the transparent conductive composition is screen printing.

14. The method of claim 10, wherein the method of applying the transparent conductive composition is dipping the substrate into the composition sufficiently to cause the composition to uniformly coat the substrate.

15. The method of claim 10, wherein the method of applying the transparent conductive composition is brushing.

16. The method of claim 10, wherein the method of applying the transparent conductive composition is selectively depositing to the substrate at predetermined locations.

17. A method for coating a substrate with a photocurable transparent conductive composition, the method comprising:

applying a transparent conductive composition to the substrate, wherein the transparent conductive composition includes;

an aliphatic acrylated oligomer selected from an aliphatic urethane diacrylate or aliphatic urethane triacrylate present in an amount from 20% to 30% of the weight of the transparent conductive composition;

an acrylated epoxy oligomer present in an amount from 5% to 9% of the weight of the transparent conductive composition;

an isobornyl acrylate monomer present in an amount from 20% to 35% of the weight of the transparent conductive composition;

a photoinitiator present in an amount from 4% to 6% of the weight of the transparent conductive composition;

a flow promoting agent present in an amount from 3% to 5% of the weight of the transparent conductive composition; and

an electrically conductive powder present in an amount from 30% to 40% of the weight of the transparent conductive composition; and

illuminating the transparent conductive composition with an UV light sufficient to cause the transparent conductive composition to be incorporated into the transparent conductive coating by the time the composition is cured.

18. The method of claim 17, wherein:

the aliphatic acrylated oligomer is 27% of the weight of the transparent conductive composition;

the acrylated epoxy oligomer is 7% of the weight of the transparent conductive composition;

the isobornyl acrylate monomer is 28% of the weight of the transparent conductive composition;

the photoinitiator is 5% of the weight of the transparent conductive composition;

the flow promoting agent is 3.5% of the weight of the transparent conductive composition; and

the electrically conductive powder is 33% of the weight of the transparent conductive composition.

19. A method of making a photocurable transparent conductive composition comprising:

mixing an isobornyl acrylate monomer and a photoinitiator in a pan;

introducing an aliphatic acrylated oligomer, a flow promoting agent and an acrylated epoxy oligomer into the pan;

mixing the aliphatic acrylated oligomer, the flow promoting agent, and the acrylated epoxy oligomer in the pan;

introducing the electrically conductive powder into the pan; and

mixing the electrically conductive powder in the pan.

20. A photocurable transparent conductive composition comprising:

at least one aliphatic acrylated oligomer selected from an aliphatic urethane diacrylate or aliphatic urethane triacrylate;

an acrylated epoxy oligomer;

an isobornyl acrylate monomer present in an amount from 20% to 35% of the weight of the transparent conductive composition;

an electrically conductive powder present in an amount from 20% to 50% of the weight of the transparent conductive composition; and

a photoinitiator.