Method of applying discrete coating patches on a moving web
AssigneeMinnesota Mining and Manufacturing Company
InventorsThomas M. Milbourn, Jerry J. Barth
Life of this patent
Estimating the term…
Abstract
An apparatus for coating a pattern of spaced discrete patches on a web of material includes an extrusion die and a metering pump which supplies coating fluid to the extrusion die from a fluid reservoir. A valve directs fluid to either the extrusion die or the fluid reservoir and a piston provides a controlled excess of flow of fluid to the extrusion die. A controller, including a digital preset counter, controls the length of the coated portions of the web, the distance between the coated portions of the web, and the timing of the valve with respect to the operation of the piston.
Claims13
A method of coating a pattern of a plurality of spaced discrete coating patches on a single web of material, wherein each patch has a length and a width, comprising the steps of:
- providing relative movement between the web of material and a coating die, wherein the coating die has a width, at speeds of at least 10 m/min;
- delivering coating fluid from a reservoir to the die at intervals corresponding to when coating is desired;
- directing coating fluid to either the die or the reservoir depending on whether coating is desired;
- providing, at the start of each patch, a controlled excess flow of coating fluid to the die to provide sharp, linear front edges of the coating patches to quickly establish the coating fluid flow from the die while maintaining a constant distance between the coating die and the web;
- providing a sharp break in the coating fluid flowing from the die to provide sharp, linear rear edges of the coating patches to quickly end the coating fluid flow from the die while maintaining a constant distance between the coating die and the web;
- extruding coating fluid onto the web at a nonexcess flow after the start of the patch while maintaining a constant distance between the coating die and the web, wherein the providing a controlled excess flow, providing a sharp break, and extruding coating steps are performed without obstructing the flow within the die and are performed to create uniform coating patches;
- controlling length of and distance between the coated patches on the web;
- and
- coordinating timing of the directing step with respect to the operation of the two providing steps.
A method of coating a pattern of a plurality of spaced discrete coating patches on a single web of material, wherein each patch has a length, comprising the steps of:
- providing relative movement between the web of material and a coating die at speeds of at least 10 m/min;
- delivering coating fluid from a reservoir to a die at intervals corresponding to when coating is desired;
- directing coating fluid to either the die or the reservoir depending on whether coating is desired;
- providing, at the start of each patch, a controlled excess flow of coating fluid to the die to provide sharp, linear front edges of the coating patches to quickly establish the coating fluid flow from the die while maintaining a constant distance between the coating die and the web;
- providing a sharp break in the coating fluid flowing from the die to provide sharp, linear rear edges of the coating patches to quickly end the coating fluid flow from the die while maintaining a constant distance between the coating die and the web;
- extruding coating fluid onto the web at a nonexcess flow after the start of the patch while maintaining a constant distance between the coating die and the web, wherein the providing a controlled excess flow, providing a sharp break, and extruding coating steps are performed without obstructing the flow within the die and are performed to create uniform coating patches;
- controlling length of and distance between the coated patches on the web;
- and
- coordinating timing of the directing step with respect to the operation of the two providing steps to permit coating of up to 100 patches per second on the web.
A method of coating a pattern of a plurality of spaced discrete coating patches on a single web of material, wherein each patch has a length, comprising the steps of:
- providing relative movement between the web of material and a coating die at speeds of at least 10 m/min;
- delivering low viscosity coating fluid from a reservoir to an die at intervals corresponding to when coating is desired;
- directing coating fluid to either the die or the reservoir depending on whether coating is desired;
- providing, at the start of each patch, a controlled excess flow of coating fluid to the die to provide sharp, linear front edges of the coating patches to quickly establish the coating fluid flow from the die while maintaining a constant distance between the coating die and the web;
- providing a sharp break in the coating fluid flowing from the die to provide sharp, linear rear edges of the coating patches to quickly end the coating fluid flow from the die while maintaining a constant distance between the coating die and the web;
- extruding coating fluid onto the web at a nonexcess flow after the start of the patch while maintaining a constant distance between the coating die and the web, wherein the providing a controlled excess flow, providing a sharp break, and extruding coating steps are performed without obstructing the flow within the die and are performed to create uniform coating patches;
- controlling length of and distance between the coated patches on the web;
- and
- coordinating timing of the directing step with respect to the operation of the two providing steps.
Dependencies are inferred from the claim text.