Method of making nanosized particles of monoazo laked pigment
AssigneeXerox Corporation
InventorsRina Carlini, Karl W. Dawson, Sandra J. Gardner, C. Geoffrey Allen
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Abstract
A nanoscale pigment particle composition includes an organic monoazo laked pigment including at least one functional moiety, and a sterically bulky stabilizer compound including at least one functional group, wherein the functional moiety associates non-covalently with the functional group; and the presence of the associated stabilizer limits the extent of particle growth and aggregation, to afford nanoscale-sized pigment particles.
Claims22
A process for preparing nanoscale particles of monoazo laked pigments, comprising:
- providing an organic pigment precursor to a monoazo laked pigment that contains at least one functional moiety,
- providing a sterically bulky stabilizer compound that contains at least one functional group, and
- carrying out a chemical reaction to form a monoazo laked pigment composition, whereby the functional moiety found on the pigment precursor is incorporated within the monoazo laked pigment and non-covalently associated with the functional group of the stabilizer, so as to allow the formation of nanoscale-sized pigment particles.
A process for preparing nanoscale-sized monoazo laked pigment particles, comprising:
- preparing a first reaction mixture comprising:
- (a) a diazonium salt having at least one functional moiety as a first precursor to the laked pigment and (b) a liquid medium containing diazotizing agents;
- and
- preparing a second reaction mixture comprising:
- (a) a coupling agent having at least one functional moiety as a second precursor to the laked pigment and (b) a sterically bulky stabilizer compound having one or more functional groups that associate non-covalently with the coupling agent;
- and (c) a liquid medium
- combining the first reaction mixture into the second reaction mixture to form a solution and
- effecting a direct coupling reaction which forms a monoazo laked pigment composition having nanoscale particle size, and wherein a functional moiety of the pigment associates non-covalently with the functional group of the stabilizer.
A process for preparing nanoscale monoazo laked pigment particles, comprising:
- providing a monoazo precursor dye to the monoazo laked pigment that has at least one functional moiety;
- subjecting the monoazo precursor dye to an ion exchange reaction with a cation in the presence of a sterically bulky stabilizer compound having one or more functional groups;
- and
- precipitating the monoazo laked pigment having nanoscale particle size, wherein the functional moiety of the pigment associates non-covalently with the functional group of sterically bulky stabilizer compound.
Dependencies are inferred from the claim text.