Production of polyvinylbutyral sheet rolls
AssigneeMonsanto Company
InventorsVan Pelt Brower, Robert A. Esposito, Thomas E. Soar
Life of this patent
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Abstract
A process comprising winding polyvinylbutyral interlayer sheet at a controlled low tension reduces blocking at the core of the roll and minimizes stretch variations within the roll and storing the roll until use at a temperature below 15.degree. C.
Claims7
A process for the production of a roll of polyvinyl butyral interlayer sheet for use in laminated glazing units which comprises (a) forwarding a polyvinyl butyral interlayer sheet through a tension-sensing device at a constant tension between 35 and 173 grams per linear centimeter;
- (b) thereafter winding the sheet onto a core rotated at a speed that is responsive to variations in tension picked up by the sensing device such that the sheet is wound at a substantially constant tension between 35 and 173 grams per linear centimeter;
- and (c) storing the roll at a temperature of below 15.degree. C. until it is used.
A process for the production of a roll of polyvinyl butyral interlayer sheet adapted for use in laminated glazing units which comprises seasoning a polyvinyl butyral sheet for at least ten days at from 50.degree. to 70.degree. C., then forwarding the seasoned sheet at a constant tension in the range of from 50 to 120 grams per linear centimeter through a tension-sensing device and thereafter winding the sheet on a core rotated at a speed that is responsive to the tension-sensing device such that the sheet is wound at the same constant tension and at a temperature of from 7.degree. to 12.degree. C. and stored at that temperature until used.
Dependencies are inferred from the claim text.