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Publication of NL6918711ApublicationCriticalpatent/NL6918711A/xx
B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
B41M5/00—Duplicating or marking methods; Sheet materials for use therein
B41M5/124—Duplicating or marking methods; Sheet materials for use therein using pressure to make a masked colour visible, e.g. to make a coloured support visible, to create an opaque or transparent pattern, or to form colour by uniting colour-forming components
B41M5/132—Chemical colour-forming components; Additives or binders therefor
B41M5/136—Organic colour formers, e.g. leuco dyes
B41M5/15—Spiro-pyrans
Landscapes
Chemical & Material Sciences
(AREA)
Chemical Kinetics & Catalysis
(AREA)
General Chemical & Material Sciences
(AREA)
Color Printing
(AREA)
Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur
(AREA)
Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography
(AREA)