Process for thick film circuit patterning
AssigneeE.I. du Pont de Nemours and Company
InventorRoupen Leon Keusseyan
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Abstract
A process for patterning thick film electrically functional patterns using a photosensitive polymer layer. A tacky photosensitive layer is applied onto a substrate surface. The photosensitive layer is imaged with a pattern using actinic radiation, the exposed areas of the photosensitive layer become hardened and non-tacky. A subsequent application of a thick film composition sheet will cause the thick film to adhere to the remaining tacky areas. Upon peeling the sheet, a thick film print pattern will be produced. This step is followed by a processing profile prescribed by the thick film composition used which results in a pattern having electrically functional properties. The invention also extends to a process wherein a thick film composition is recovered from a used sheet.
Claims16
A process for forming a pattern having electrically functional properties on a substrate comprising the steps of:
- (a) providing a photosensitive layer having a tacky surface disposed on a substrate;
- (b) providing a transfer sheet comprising a removable support and at least one layer of a thick film composition disposed on the support;
- (c) image-wise exposing the photosensitive tacky surface to form an imaged layer having unexposed tacky and exposed non-tacky areas;
- (d) applying the thick film composition of the transfer sheet onto the imaged layer;
- (e) separating the transfer sheet from the substrate wherein the thick film composition substantially remains on the support in the exposed non-tacky areas of the imaged layer and substantially adheres to the unexposed tacky areas to form a patterned thick film composition;
- and
- (f) subjecting the patterned thick film composition to heat thereby forming a patterned article.
A method for using a photosensitive layer to form a pattern having electrically functional properties with a thick film composition, comprising the steps of:
- (a) forming tacky and non-tacky areas on the surface of a photosensitive layer by image-wise exposing the photosensitive layer to actinic radiation to form an image-wise exposed surface;
- (b) contacting the image-wise exposed surface with a thick film composition which substantially adheres to the tacky areas but does not adhere to the nontacky areas to form a pattern of thick film composition on the image-wise exposed surface;
- and
- (c) firing the thick film composition on the image-wise exposed surface.
Dependencies are inferred from the claim text.