Imaging compositions and methods
AssigneeMinnesota Mining and Manufacturing Company
InventorsDonald D. Buerkley, Norman P. Sweeny, Daniel N. Vivona
Life of this patent
Estimating the term…
Abstract
Color-forming precursor compositions comprising a metal-complexing compound having a plurality of ligand groups and color-activating compositions comprising transition metal salts of oleophilic, organic acids are combined to form dark, permanent images on substrates. The methods and compositions are particularly useful for providing permanent fingerprints and other dermographs.
Claims28
A color-forming precursor composition comprising an organic color-forming, metal-complexing compound having a plurality of ligand groups and an organic cosolvent for said compound, said compound having the formula
- R.sup.1 (L).sub.n
- wherein
- n is a number from 2 to about 100,
- L is a metal-complexing ligand group, and
- R.sup.1 is a polyvalent organic group having a valence of n, provided that when n is 2 or 3 and R.sup.1 is a fatty hydrocarbon group, R.sup.1 contains about 34 and 51 carbon atoms respectively,
- said compound being capable of complexing with transition metal ions to form metal-containing colored products which are substantially insoluble in organic cosolvents for said compound.
A color-forming precursor composition comprising an organic color-forming, metal-complexing compound having a plurality of ligand groups and an organic cosolvent for said compound, said compound having the formula ##STR14## wherein n is a number from 2 to about 100
- R.sup.1 is a polyvalent organic group having a valence of n
- R.sup.2 is an organic group independently selected from the group consisting of H, or hydrocarbyl,
- a is an integer from 1 to 5, and
- b is o or an integer from 1-4 and a+b is less than 6 .
Dependencies are inferred from the claim text.