Abstract: A thinner, less-expensive-to-produce, and more easily handled, opaque sheet is formed by coextrusion of two polymeric layers containing relatively low loadings of black pigment around a third layer of polymer which is pigmented at levels higher than would be practical using conventional extrusion processes, rather than a coextrusion procedure. The sheet is an improved product for use in packaging photographic film or like products to be protected from light.

Abstract: Novel process for dispersing electroconductive carbon black to make novel conductive web products and the dispersions produced therewith. The process comprises dispersing said carbon black in an aqueous media using tris (2,3 dibromopropyl) phosphate, or the like, as a dispersing agent and then coating a porous fibrous substrate with the resulting carbon black dispersion.

Abstract: A process for improving the readability of a data-recording line on a chart recording paper whereby the improvement is achieved by moving the recording line across a field largely composed of a matrix of dots. The procedure is particularly advantageous in improving the readability of thin lines achievable with pressure-responsive or thermographic paper, but it is also advantageous when common inking procedures are used. A novel chart paper consisting of a dot matrix format is also disclosed.

Abstract: A thinner, less-expensive-to produce, and more easily handled, opaque sheet is formed by coextrusion of two polymeric layers containing relatively low loadings of black pigment around a third layer of polymer which is pigmented at levels higher than would be practical using conventional extrusion processes, rather than a coextrusion procedure. The sheet is an improved product for use in packaging photographic film or like products to be protected from light.

Abstract: An information-bearing article for conveying indicia from one person to a second person in such a way that the information cannot be surreptitiously detected by an intervening person.Thus, the information-bearing means is so constructed that detection thereof necessarily requires some irreparable and detectable disfigurement or mutilation of the information-bearing article. Use of the article in lottery ticket distribution and use in connection with the transfer of highly confidential governmental or business information, are typical applications.The most advantageous construction of the invention combines means to avoid surreptitious detection of the hidden indicia by optical, chemical, thermal and mechanical processes.

Abstract: A process and apparatus for selectively compressing paper stock of the type which is used as a protective backing sheet for adhesive-coated systems. The process comprises use of a novel compression tool, the precise characteristics of which depend on the paper stock being utilized. The compression tool comprises a blunt, rotatable, circular, working edge which has a radius of at least 0.02, but preferably at least 0.04 inches in diameter and at least one half of the thickness of the paper being weakened. This tool advantageously comprises the compressing edge, being mounted integrally with a bearing surface which makes pressure control easier and limits penetration of the tool. In the preferred embodiments of the invention, the bearing surface is faced with elastomeric material. Disclosure is also made of a novel release sheet and adhesive sheet assembly which is manufactured utilizing the process and apparatus of the invention.