Process for applying a composite insulative coating to a substrate

Patent 4921723 Issued on May 1, 1990. Estimated Expiration Date:

October 16, 2007. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Process for chemically bonding a poly-p-xylylene to a thermosetting resin and article produced thereby
Patent #: 4123308
Issued on: 10/31/1978
Inventor: Nowlin , et al.

Process for forming polymeric paraxylylene coatings and films possessing improved oxidation resistance
Patent #: 4176209
Issued on: 11/27/1979
Inventor: Baker , et al.

Electrets Patent #: 4291245
Issued on: 09/22/1981
Inventor: Nowlin , et al.

Inventors

Assignee

The Curators of the University of Missouri

Application

No. 109079 filed on 10/16/1987

US Classes:

427/488, Plasma initiated polymerization257/E21.505, Insulative mounting semiconductor device on support (EPO)427/96.6, Barrier to diffusion of specific fluid (e.g., silicone rubber, selectively permeable membrane which excludes water or moisture, etc.)427/96.8, Vapor or gas deposition427/255.4, Base supplied constituent427/255.7, Plural coatings applied by vapor, gas, or smoke427/294, VACUUM UTILIZED PRIOR TO OR DURING COATING427/407.1, Synthetic resin coating427/495, Polymerization involving the control of oxygen containing gas as an inhibitor (e.g., air, etc.)427/570Utilizing plasma with other nonionizing energy sources

Examiners

Primary: Pianalto, Bernard

Attorney, Agent or Firm

Senniger, Powers, Leavitt and Roedel

Foreign Patent References

1445546 GB. 08/11/1976

International Class

B05D 003/06

Abstract

A process for applying an adherent electrically insulative moisture-resistant composite coating to a substrate. A thin, adherent, highly cross-linked, substantially liquid moisture-impervious primer coating is provided on the substrate by glow discharge polymerization of a low molecular weight hydrocarbon monomer in a low pressure chamber containing the substrate, the monomer being selected from among methane, ethane, propane, ethylene, and propylene. A second polymeric coating layer is provided over the primer coating by glow discharge polymerization of a second precursor comprising a hydrocarbon or substituted hydrocarbon. The precursor exhibits a hydrogen yield of not greater than about 0.75 hydrogen atoms per molecule under the glow discharge polymerization conditions under which the second layer is deposited, whereby the second polymeric coating layer is substantially resilient and strongly bonded to the primer coating and the second layer comprises a high concentration of surface and bulk free radicals.

Other References

Hahn et al., "Biocompatibility of Glow Discharge Polymerized Films and Vacuum Deposited Parylene", J. Appl. Polym. Sci.: Appl. Polym. Symp., 1984, 38, 55-64
Charlson et al, "Electrical Properties of Glow Discharge Polymerized Films," Org. Coat. Appl. Polym. Sci. Proc., 1982, 47, 146-50
Hahn et al, "Biocompatibility of Glow Discharge Polymerized Films," Org. Coat. Appl. Polym. Sci. Proc., 1982, 47, 386-90
Raschke et al, "Polyparaxylylene Electrets Usable at High Temperatures," J. Appl. Polym. Sci., 1980, 25(8), 1639-44
Yasuda et al, "Improvement of Blood Compatibility of Membranes by Discharge Polymerization," Am. Chem. Soc., Div. Org. Coat. Plast. Chem., Pap. 1974, 34(1), 574-7
Lee et al, "Polymer Films for Semiconductor Passivation. II. Sputtering," Soc. Plast. Eng., Tech. Pap. 1972, 18(Pt. 1), 419-23
Sharma et al, "Effect of Surface Energetics of Substrates on Adhesion Characteristics of Poly-p-Xylylenes", J. Adhes., 1982, 13(3-4), 201-14
Sharma et al, "Effect of Glow Discharge Treatment of Substrates on Parylene-Substrate Adhesion", J. Vac. Sci. Technol., 21(4), Nov./Dec. 1982
Nichols et al, "Evaluating the Adhesion Characteristics of Glow-Discharge Plasma-Polymerized Films by a Novel Voltage Cycling Technique", J. Appl. Polymer Sci.: Applied Polymer Symposium, 38, 21-33 (1984)
H. Yasuda, Plasma Polymerization, Academic Press (1985), pp. 193-19