Patent number: 5384237
Abstract: A thermal-dye-bleach construction comprising a dye in association with a thermal dye-bleaching agent of general formula I: ##STR1## wherein: each of R.sup.a and R.sup.b are individually selected from: hydrogen, an alkyl group, an alkenyl group, a cycloalkyl group, an aralkyl group, an aryl group, and a heterocyclic group, and preferably, both R.sup.a and R.sup.b represent hydrogen;p is one or two, and when p is one, Z is a monovalent group selected from: an akyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group, and a heterocyclic group, and when p is two, Z is a divalent group selected from: an alkylene group, an arylene group, an alkenylene group, an alkynylene group, an aralkylene group, a cycloalkene group, and a heterocyclic group; and,M.sup.+ is a cation which will not react with a carbanion generated from the thermal-carbanion-generating agent in such manner as to render the carbanion ineffective as a bleaching agent for the dye.
Type:
Grant
Filed:
January 25, 1994
Date of Patent:
January 24, 1995
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Dian E. Stevenson, Mark P. Kirk, Sylvia A. Farnum, William C. Frank, Randall H. Helland, Jonathan P., Kitchin, Roger A. Mader, Mark B. Mizen, Richard A. Newmark, William D. Ramsden, Kumars Sakizadeh, Terence D. Spawn, George V. Tiers
Patent number: 5324627
Abstract: A thermal-dye-bleach construction comprising a dye in association with a thermal dye-bleaching agent of general formula I: ##STR1## wherein: each of R.sup.a and R.sup.b are individually selected from: hydrogen, an alkyl group, an alkenyl group, a cycloalkyl group, an aralkyl group, an aryl group, and a heterocyclic group, and preferably, both R.sup.a and R.sup.b represent hydrogen;p is one or two, and when p is one, Z is a monovalent group selected from: an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, an aralkyl group, an aryl group, and a heterocyclic group, and when p is two, Z is a divalent group selected from: an alkylene group, an arylene group, an alkenylene group, an alkynylene group, an aralkylene group, a cycloalkene group, and a heterocyclic group; and,M.sup.+ is cation which will not react with acarbanion generated from the thermal-carbanion-generating agent in such manner as to render the carbanion ineffective as a bleaching agent for the dye.
Type:
Grant
Filed:
December 21, 1992
Date of Patent:
June 28, 1994
Assignee:
Minnesota Mining and Manufacturing Company
Inventors:
Dian E. Stevenson, Mark P. Kirk, Sylvia A. Farnum, William C. Frank, Randall H. Helland, Jonathan P. Kitchin, Roger A. Mader, Mark B. Mizen, Richard A. Newmark, William D. Ramsden, Kumars Sakizadeh, Terence D. Spawn, George V. Tiers
