A method is disclosed for washing silver halide photographic emulsions, including desalting and/or concentrating, based on depletion phase separation mechanism, wherein phase separation is effected by the addition of water-soluble non-interactive and non-adsorbing carboxyl polymers. The process involves the separation of the supernatant fluid, containing the undesirable water soluble salts and the added phase separating agents, from the washed and condensed silver halide phase for desalting and ...

Apparatus for drying coated web material and preferably moving web material comprises a nozzle, means for supplying air to the nozzle and means to distribute the air through said nozzle substantially uniformly across the web width, said nozzle arcing from a position perpendicular with respect to the plane of the web to a position substantially parallel with respect to the plane of the web, said nozzle having an exit slot wherein the air is discharged from the exit slot at an angle of between 1.d...

A merocyanine dye having the formula: ##STR1## wherein: R.sub.1 and R.sub.2 independently are H, alkyl, alkoxy or aryl, R.sub.7 and R.sub.8 are H or any of R.sub.1 and R.sub.2, R.sub.1 and R.sub.7, R.sub.2 and R.sub.8 can together comprise the atoms necessary to form a fused aromatic ring on the benzene radical to which they are attached; R.sub.5 and R.sub.6 comprise alkyl of from 1-18 carbon atoms provided that the sum of the carbon atoms in R.sub.5 and R.sub.6 is at least 8; R.sub.9 is an alky...

A process for selectively preparing isomers of polysubstituted pyrylium salts from isoolefins or isoolefin precursors comprises diacylating the isoolefin or isoolefin precursor with a carboxylic acid anhydride in the presence of an acid having a Hammett acidity function, at about 22.degree.-25.degree. C. when pure, between -10 and -5. This method is selective to obtain the most substituted isomer of pyrylium salt that can be obtained from the isoolefin or isoolefin precursor.

A method of obtaining a photothermographic or thermographic film with reduced fog, such as pepper fog, comprises preparing a dispersion of: an oxidation-reduction image-forming combination comprising: a silver behenate oxidizing agent the improvement wherein said oxidizing agent contains less than about 800 micrograms of polyunsaturated and 3800 micrograms of monounsaturated fatty acid silver salts per gram of oxidizing agent or the film contains less than about 100 micrograms of polyunsaturated...

A novel copper (I) complex having the formula Cu[P(OR).sub.3 ].sub.n BH.sub.3 CN wherein R is lower alkyl and n is an integer from 1 to 3 is employed as an actinic radiation sensitive component in an imaging process comprising imagewise exposing a support carrying the copper (I) complex to actinic radiation and developing an image in a chemical or physical development bath. The complex has excellent speed and may be handled under room light conditions prior to development.

A means of selectively lysing leukocytes but not bacteria is described. This technique is useful in conjunction with a reduction analysis to provide a rapid interference-free determination of either leukocytes or bacteria in clinical samples. The method is adaptable to a solution or dry element mode.

Reticulation caused by swelling with processing solutions in photographic elements is reduced for elements containing at least two contiguous gelatin-containing layers wherein the uppermost layer has a lateral swell coefficient at least 10% greater than the lower gelatin-containing layer before polymer addition and wherein said uppermost layer comprises an essentially non-diffusible vinyl polymer having reactive groups which crosslink by reaction with primary amine or secondary amine groups on g...

An optical element, consisting essentially of an amorphous compound and having a varying refractive index, is prepared by introducing a melt of the material into a mold and cooling it in such a manner that the material gradually solidifies, while simultaneously applying a programmed pressure to the cooling melt. When the material is fully solidified, it possesses a refractive index gradient. An element manufactured by this method has a capacity for guiding and focusing light.

There are described stable fluorescent labels comprising a complex of lanthanide metal and a chelating agent comprising a nucleus which is a triplet sensitizer having a triplet energy greater than that of said lanthanide metal and at least two heteroatom-containing groups which form coordinate complexes with lanthanide metals and a third heteroatom-containing group or heteratom in or appended to the triplet sensitizer. Labeled physiologically active materials useful in specific binding assays su...