Abstract: Colorless precursors of preformed image dyes are provided which are useful as the color image-forming materials in thermal imaging systems. These colorless precursors possess at least one thermal protecting group that undergoes fragmentation upon heating and at least one leaving group that undergoes irreversible elimination upon heating, said protecting and leaving groups maintaining the precursor in its colorless form until heat is applied to effect removal of these groups whereby the precursor is converted to an image dye.

Abstract: The storage and processing times of sprayed concrete can be significantly extended by the addition of a retarder, a chemical compound which is capable of chelating with calcium ions. Preferred retarders are phosphonic acid derivatives which have at least one amino and/or hydroxyl group. The retarder can be used for both wet- and dry-sprayed concrete, the usual accelerators can be used for activation, and the strength is not adversely affected.

Abstract: A novel class of N-substituted triarylmethane sulfonamides is provided which undergo reversible oxidation into colored form and reversible reduction of the oxidized form into colorless form. The N-substituted triarylmethane sulfonamides can be represented by the formulae: ##STR1## wherein B is a carbocyclic ring or rings; T is a 5- or 6-membered ring; Y is a moiety selected from ##STR2## wherein E, positioned ortho or para to said --OH group, is selected from --OH, --NH.sub.2, --NHR', --NR'R" and --NHSO.sub.

Abstract: A hardenable monomer composition useful for flooring composition, grouts, mortars and the like comprises a mixture of crosslinkable acrylic monomer, carbon black and/or polyester- or polyether-methane oligomer having at least two polymerizable double bonds and a paraffin oil.The monomer is preferably of the formula I ##STR1## and there is preferably present other monomers, particularly hydroxypropyl methacrylate.

Abstract: A method of accessing water from an aquifer which underlies an impervious stratum without contamination of the aquifer by polluted water from above the stratum by drilling a bore hole to the aquifer, comprises the steps of(a) drilling a first bore hole into, but not through the impervious stratum and a second bore hole of smaller diameter to the aquifer;(b) inserting therein a protective tube of diameter intermediate between those of the bore holes and which extends to the ground surface; and(c) adding a protective mortar to the annular space between the protective tube and the larger diameter bore hole;there being circumferentially wound around the tube at the level of the protective mortar, transfer tubing which comprises radial perforations which permit passage of fluids, e.g. sealing composition from the interior of the transfer tubing to the mortar. The method works best with certain reinforced mortar formulations.

Abstract: An aqueous solution, for use as a cement dispersing agent, of a polymer salt, which is formed by reacting a polycarboxylic acid with a nitrogenous acrylic polymer.

Abstract: A process for improving the rebound properties of sprayed concrete comprises the inclusion therein of micro-silica which has been pretreated with from 2 to 25% by weight thereof of a liquid selected from water, an alkanolamine, a polyol and an aqueous solution of at least one concrete additive, an alkanolamine, a polyol and a water-soluble cellulosic compound. The process is especially effective when used in conjunction with the dry spraying process.

Abstract: A method for applying a cementitious composition to a surface comprising1) adding to the cementitious compositiona) a set retarding agent;b) a cement quick-setting agent;c) a cement dispersing agent;d) a slow release dispersing agent, that hydrolyzes under alkaline conditions to form a dispersing agent; and2) applying the concrete to a surface while the concrete is fluid.

Abstract: Leuco dyes are provided which comprise the coupling product of a N-acyl substituted aromatic amino color developer and a dye-forming coupler moiety substituted at the coupling carbon with a thermally removable leaving group. Thermal imaging systems employing these leuco dyes have the advantage of reduced bubble formation relative to thermal imaging systems employing prior art leuco dyes containing a group which thermally fragments into one or more gases.

Abstract: There are disclosed dye-providing compounds comprising color coupler dyes substituted on the phenylene diamine portion with one or two cyclic 1,3 -sulfur-nitrogen groups. The dye-providing compounds are capable of releasing the coupler dye upon cleavage in the presence of silver ions or a soluble silver complex. The dye-providing compounds are useful as image-forming materials in color thermographic, photothermographic and other photographic processes.

Abstract: Sheet materials for use in thermal transfer imaging systems comprising a donor sheet and a receiving sheet are provided wherein the donor sheet and the receiving sheet do not stick to each other during thermal processing.

Abstract: A novel class of N-substituted triarylmethane sulfonamides is provided which undergo reversible oxidation into colored form and reversible reduction of the oxidized form into colorless form. Preferred embodiments comprise xanthene sulfonamides having N-aryl substituents, e.g., hydroquinone substituents. These compounds possess redox potentials ranging between about +200 to -500 millivolts and thus are useful as dyes for producing photographic, photothermographic, thermal, and pressure-induced images, as well as being useful as redox indicators in a wide variety of biological and chemical reactions.

Abstract: Photothermographic and thermographic diffusion transfer image-recording materials are provided wherein an auxiliary ligand for silver ions is employed to enhance transfer image density and discrimination.

Abstract: A storable cement-mortar dry mix, which comprises the components cement, aggregate, reaction resin and hardener in a single mixture, wherein the hardener is present as the reaction product of the hardener with an organic acid or a functional derivative thereof.

Abstract: There are disclosed compounds comprising at least one cyclic 1,3-sulfur-nitrogen substituted color-providing material and at least one ballast group which are linked to each other through a triazine group. The compounds are capable of releasing the color-providing material upon cleavage in the presence of silver ions or a soluble silver complex. The color-providing compounds are useful as image-forming materials in color thermographic, photothermographic and other photographic processes.

Abstract: There are disclosed certain bis(aminoethanethiols) and the salts thereof which find utility as intermediates in the preparation of certain dye-providing compounds useful in photographic imaging systems.

Abstract: There are disclosed color-providing compounds comprising two or more cyclic 1,3 sulfur-nitrogen groups and two or more color-providing moieties, i.e., complete dyes or dye intermediates, capable of releasing the color-forming moieties upon cleavage in the presence of silver ions or a soluble silver complex. The color-providing compounds are useful as image-forming materials in color photographic processes.

Abstract: Disclosed is a class of bridged phthalides and sulfinate esters which exhibit reversible thermochromism. At room temperature and in the presence of base, these compounds are substantially colorless but upon the application of heat they become colored, reverting to their original colorless or weakly colored state upon cooling. This colorless to colored, temperature-dependent cycle can be repeated many times. These compounds have utility as temperature sensors and as thermal pH indicators.

Abstract: This invention relates to the use of a compound containing at least two epoxide moieties in the protective topcoat layer and/or in a layer on top of the protective topcoat layer of certain thermographic recording films to reduce gouging and streaking of the printed image film and to reduce head build-up on the thermal printhead.

Abstract: An admixture for inhibiting chloride-induced corrosion in steel reinforcing in place in concrete comprises an O/W emulsion wherein the oil phase comprises an unsaturated fatty acid ester and ethoxylated nonyl phenol and the ester of an aliphatic carboxylic acid with a mono-, di- or trihydric alcohol and the water phase comprises a saturated fatty acid, an amphoteric compound, a glycol and a soap. The admixture is added to the concrete prior to placement.