Heat curable conductive ink

• US 4,406,826 A
• Filed: 03/05/1981
• Issued: 09/27/1983
• Est. Priority Date: 03/05/1981
• Status: Expired due to Fees

• Current Assignee: W.R. Grace & Co.-Conn. (WR Grace & Company)
• Original Assignee: WR Grace & Company
• Inventors: Morgan, Charles R., Ketley, Arthur D.
• Primary Examiner(s): Marquis, Melvyn I.
• Assistant Examiner(s): Lilling, Herbert J.
• Application Number:
  US06/241,144
• Time in Patent Office: 936 Days
• Field of Search: 260/42.14, 260/42.52, 260/42.22, 252/502, 252/513, 252/514, 252/500, 252/511, 523/223, 524/780, 524/754, 524/781, 524/783, 524/785, 524/786, 524/789, 524/878, 524/881, 524/854
• US Class Current: 252/512
• CPC Class Codes: B41M 7/009 using thermal means, e.g. infrared radiation, heat
• CPC Class Codes: C08G 75/045 from mercapto compounds and unsaturated compounds
• CPC Class Codes: C08G 75/12 Polythioether-ethers C08G75/0245 takes precedence
• CPC Class Codes: C09D 11/106 containing macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: C09D 11/52 Electrically conductive inks
• CPC Class Codes: H05K 1/095 for polymer thick films, i.e. having a permanent organic polymeric binder

Abstract

This invention relates to a heat curing process and to a solventless screen printable, heat curable conductive ink composition comprising

(1) an ethylenically unsaturated member of the group consisting of

(a) a liquid, ethylenically, unsaturated monomer, oligomer or prepolymer of the formula: ##STR1## wherein R is H or CH₃, R₁ is an organic moiety and n is at least 2,

(b) a polythiol in combination with (a) supra,

(c) a polythiol in combination with a liquid ethylenically unsaturated monomer, oligomer or prepolymer of the formula: ##STR2## wherein R₂ is H or CH₃, R₃ is an organic moiety and n is at least 2, and

(d) mixtures of (a), (b) and (c),

(2) a thermal initiator, and

(3) an electrically conductive material.

Heating of the composition in a desired pattern on a substrate results in a printed electric circuit.

Claims

1. A solventless screen printable, heat curable conductive ink composition comprising

(1) a member of the group consisting of

(a) a polythiol in combination with a liquid, ethylenically, unsaturated monomer, oligomer or prepolymer of the formula:

##STR11## wherein R is H or CH₃, R₁ is an organic moiety and n is at least 2,

(b) a polythiol in combination with a liquid ethylenically unsaturated monomer, oligomer or prepolymer of the formula;

##STR12## wherein R₂ is H or CH₃, R₃ is an organic moiety and n is at least 2, and

(c) mixtures of (a) and (b);

(2) a thermal initiator; and

(3) a metal as an electrically conductive material in the range of 65-85 weight percent of the conductive ink composition.

2. The composition according to claim 1 wherein the group member is a liquid, ethylenically, unsaturated monomer, oligomer or prepolymer of the formula:

##STR13## wherein R is H or CH₃, R₁ is an organic moiety and n is at least 2, and a polythiol.

3. The composition according to claim 1 wherein the group member is a polythiol in combination with a liquid ethylenically unsaturated monomer, oligomer or prepolymer of the formula:

##STR14## wherein R₂ is H or CH₃, R₃ is an organic moiety and n is at least 2.

4. The composition according to claim 1 wherein the composition contains a reactive diluent.

5. The composition according to claim 1 wherein the thermal initiator is a substituted or unsubstituted pinacol having the general formula:

##STR15## wherein R₁ and R₃ are the same or different substituted or unsubstituted aromatic radicals, R₂ and R₄ are substituted or unsubstituted aliphatic or aromatic radicals and X and Y which may be the same or different are hydroxyl, alkoxy or aryloxy.

6. The composition according to claim 1 wherein the thermal initiator is an organic peroxide of the general formula:

space="preserve" listing-type="equation">R-O-O-(R.sub.1 -O-O).sub.n -R

wherein n=0 or 1, R is independently selected from hydrogen, aryl, alkyl, aryl carbonyl, alkaryl carbonyl, aralkyl carbonyl and alkyl carbonyl and R₁ is alkyl or aryl, said alkyl groups containing 1 to 20 carbon atoms.