IL42500A - Production of high strength packaging paper from straw - Google Patents

Claims (1)

1. WHAT IS CLAIMED IS: ^ strength w 1. A. straw paper having cons tituently more than 40 percent by weight of straw fiber with a majority of the straw fibers being in the range of approximately 0,70 to 4.00 millimeters in length, a proportion of at least one other type of fiber^ which is randomly and generally uniformly intermixed with the straw fibers, and the straw paper having substantially all of its fibers locally crimped and intertwined such that the paper exhibits substantial permanent extensibility in excess of the paper web as laid, 2. The straw paper of Claim 1 wherein the other fiber is a softwood. 3. The straw paper of Claim 1 wherein the straw fiber is a cereal straw* 4. The straw paper of Claim 1 wherein the other fiber is present in excess of approximately 10 percent by weight . 5. The straw paper of Claim 4 wherein the paper includes 1.0 to 2.5 percent of rosin sizing by total weight. 6o The straw paper of Claim 1 wherein the basis weight of the paper is 90 pounds or greater and additives are present in amount of less than 1.0 percent of the fiber weight, 7. The process of making^ straw paper including the steps as follows? introducing cut straw into a digester, metering cooking liquor into mixture with the straw, cooking the straw-liquor mixture under pressure and in the presence of superheated steam, blowing the straw, removing the spent liquor, mixing the straw with such as softwood pulp, blending to form a furnish, passing the furnish to the papermaking wire at a consistency in on the paperraaking wire under the influence of suction to remove water, drying the web to a range of approximately 30 to 45 percent moisture by weight, passing the partially dried web to a pressure nip, upsetting the fibers of the web within the plane of the web surfaces and then passing the web to drying rolls to complete the drying, 8. The process of Claim 7 wherein the weight of solids on the wire is approximately 10 percent lower than the basis weight at the dry end of the papermaking machine., 9„ The process of Claim 7 wherein rosin sizing is added to the furnish. The process of Claim 7 wherein the consistency is approximately 0,65 percent. The process of Claim 7 wherein the web is dried to approximately 37 percent by weight prior to upsetting. 12, The process of Claim 7 wherein the web is pas to the upsetting nip under tight draw. The process of Claim 12 wherein the web is pa to the drying rolls for final drying under slack draw. Γ P. O. Box 33116 , Tel-Aviv Attorneys for Applicant