Abstract: Alkylation processes wherein diazoalkane alkylation reagents are generated in situ and utilized to alkylate substrates are disclosed. These processes utilize the relatively slow base-catalyzed decomposition of an N-alkyl, N-nitrosourea to produce a corresponding diazoalkane alkylation reagent, followed by the much faster reaction between the alkylation reagent and the substrate to be alkylated. Generically, suitable ureas can be represented by the structural formula, ##EQU1## wherein R represents the alkyl moiety to be added to the substrate; R can be alkyl, cycloalkyl, heteroalkyl, aralkyl or heterocyclic.This process is useful in producing alkylated products without the concomitant disadvantage of building up significant amounts of diazoalkane alkylation reagents during the course of the reaction, many of which have deleterious properties.

Abstract: A coherent silver image which is bonded to the grained surface of an aluminum lithographic plate having an aluminum oxide layer thereon is transformed into a hydrophilic non-image area by contacting the silver image with a viscous composition comprising an aqueous nitric acid solution of sufficient concentration to rapidly effect the removal of the silver image and thereby expose the aluminum oxide under this image and wherein the viscous composition has a viscosity of at least about 500 centipoises. The preferred viscous composition is a thixotropic composition consisting essentially of (1) an aqueous solution of nitric acid present in an amount between about 35% and 70% by volume based upon the total volume of nitric acid solution, and (2) finely divided inert metal oxide capable of imparting thixotropic properties to the solution.

Abstract: An electrophotographic method is disclosed which produces multiple electrophotograhic copies from the same electrostatic image by multiply cycling the electrostatic image through development and transfer steps. To reduce copy density losses in subsequent copies, the biasing potential applied across the development zone is reduced on subsequent cycles of the electrostatic image through the development zone.

Abstract: Continuous tone images are reproduced on a plate having metallic images adherently and preferably conductively bonded to a physically roughened support by contacting with a photographic physical developer an imaging medium comprising a physically developable image of the continuous tone image. The process has the capability of producing an imaged plate containing metal images of varying contrast and varying tonal range and then using the imaged plate as a printing plate. A preferred copy medium comprises a thin silver halide layer coated on a grained and anodized aluminum support.

Abstract: Photoconductive compositions are disclosed which are formed from merocyanine dyes, preferably dispersed in insulating binders.

Abstract: A clip is disclosed which is used to support signage having information thereon. The clip is uniquely designed so that it can be inserted into a standard price-tag display channel such as that used on the edge of supermarket shelves, or alternatively be secured to rod-like supports such as wire, railing, posts, etc. or to a side of cartons.The clip is continuously formed from resilient sheet material, such as spring steel, into attaching, connecting, release and gripping members which are all generally planar in shape. A continuous nature is obtained by having these members terminate in reverse bends from which the next member extends. A dimension of the attaching member is appropriate for resilient insertion into a display channel and the attaching member also has one or more tongues which extend towards the connecting member to provide means for mounting the clip on rod-like supports or carton sides.

Abstract: A data bearing card having a magnetizable, transparent, colorless coating thereon is disclosed. The coating can comprise a transparent, colorless plastic matrix containing a dispersed particulate crystalline phase. The dispersed phase is prepared by mixing 20-60% of a rare earth compound containing a colorless ferromagnetic ion such as gadolinium with 0.1-5% of titanium dioxide or zirconium oxide, 0.05-2.5% of an inorganic fluoride salt and the balance up to 100% of a glass forming matrix such as inorganic borates. The mixture is heated above its melting point to form a homogeneous melt and subsequently crystallized. The resulting crystalline product can be ground to any desired particle size for dispersion in the transparent plastic matrix.In general, the coating composition is useful in all applications where magnetic coatings are presently used.

Abstract: A frame for displaying a poster is disclosed which is formed from a plurality of frame members joined together. The poster can be retained in a mounting groove or slot provided on each frame member. Each frame member also contains first and second guide means defining a slot therebetween into which a joiner, such as an L-shaped angle joiner, can be inserted to join frame members together.

Abstract: Improved techniques for vacuum evaporating glass, using an electron beam to vaporize the glass, onto a polymeric substrate is disclosed. Suitable substrates include ophthalmic lenses formed from polymeric materials such as polymerized CR-39 resin.The improved technique necessitates the maintenance of certain critical coating conditions. These conditions are: (a) low background pressures; and, (b) an angle of glass vapor impringement below about 40.degree., measured from the normal; and, (c) an elevated substrate temperature. Additionally, the source glass has a relatively low water content and a relatively low thermal coefficient of expansion.

Abstract: A process is disclosed for applying an adherent, optically clear, abrasion resistant coating to plastic ophthalmic substrates such as plastic lenses. The process includes: (a) forming a partially hydrolyzed solution of a vinyltri(lower alkoxy)silane, such as vinyltriethoxysilane, in a water-miscible, volatile, organic solvent, the silane being present from 25-75% by weight; (b) applying a thin, uniform coating of the partially hydrolyzed solution to a clean surface of the ophthalmic lens; (c) maintaining the coated substrate in a high humidity and preferably elevated temperature environment until the silane is substantially completely hydrolyzed; and, (d) dehydrating the coated substrate under low humidity conditions at an elevated temperature below the temperature at which the substrate degrades until an adherent, abrasion resistant coating is formed. Plastic lenses and other ophthalmic plastic components coated according to the above process are also described.

Abstract: An improved apparatus is disclosed for transferring toner from the surface of a toner-bearing drum, such as a xerographic drum, to a support medium for the toner, such as plain paper. The improvement relates to apparatus of the type which employs a transfer web or belt to remove toner from the toner-bearing drum and to transfer it to a support medium. In such apparatus, it is typical for the transfer web to be at least partially driven by means of its contact with the toner-bearing drum and/or transfer rollers.The improvement described herein comprises providing means for simultaneously disengaging the toner-bearing drum and at least one of the transfer rollers from the transfer web at least once per web cycle, and also providing means for mechanically correcting web alignment and registration while the toner-bearing drum and transfer roller are disengaged. Suitable means for disengaging the toner-bearing drum and transfer roller include the provision of indented surfaces on the drum and transfer roller.

Abstract: Gelable or gelled compositions are disclosed which comprise a liquid medium, agar, and a combination of natural gum gel-forming agents including xanthan gum and locust bean gum. The gelable dispersions are easily gelled by heating to the gel-critical temperature and subsequently cooling them below the setting temperature. In the gelled state, these compositions are useful as carriers for many types of liquids including photo-processing solutions and therapeutic solutions.

Abstract: Polymeric replica molds formed from certain specific polymeric compositions are disclosed. The polymeric compositions impart properties to the replica molds which allow the casting of high-quality plastic optical components such as ophthalmic lenses.Among the polymeric compositions which have been found useful are: (1) cross-linked polymethyl methacrylate; (2) a copolymer of 99-20 parts methyl methacrylate and 1-80 parts acrylonitrile, preferably but not necessarily cross-linked; (3) cross-linked polystyrene; (4) a cross-linked copolymer of 90-10 parts styrene and 10-90 parts acrylonitrile; and, (5) a cross-linked copolymer of 90-10 parts styrene and 10-90 parts methyl methacrylate.Replication processes including the steps of forming the polymeric replica molds described herein and subsequently using them in the casting of plastic lenses from materials such as polymerized allyl diglycol carbonate are also disclosed.