The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 27, 1994
Filed:
Jun. 17, 1993
Stephen P Singer, Spencerport, NY (US);
Paul B Merkel, Rochester, NY (US);
Bernard Arthur Clark, Berkshire, GB;
Paul Louis Stanley, Harrow, GB;
Eastman Kodak Company, Rochester, NY (US);
Abstract
A photographic element contains a light-sensitive silver halide layer having associated therewith a coupler which is a pyrazolone compound with a coupling-off substituent at the -4-position, said compound having the formula: ##STR1## wherein each R.sup.1 is independently a substituted or unsubstituted alkylsulfonyl or arylsulfonyl group; each R.sup.2 and R.sup.3 is independently a substituent; R.sup.4, R.sup.5, and R.sup.6 are independently hydrogen or substituted or unsubstituted alkyl groups; m and n are independently 0 or 1 but both are not 0; x1 and x2 are independently 0 to 5; and y is 0 to 3; provided that each of R.sup.3, R.sup.4, R.sup.5, and R.sup.6 is selected such that the calculated log P of the thiophenol corresponding to the substituent at the 4-position of the pyrazolone is at least 4. The photographic element provides an improved combination of low continued coupling together with a magenta hue exhibiting a long wavelength of maximum absorption.