Lexmark International, Inc.

Trent Duane Peter

Kasturi Rangan Srinivasan

Rahel Bekru Bogale

Tao Yu

Anna Sara McLeland

Brian David Munson

John Melvin Olson

Jing X Sun

Gary Allen Denton

Cary Patterson Ravitz

John Joseph Kraseski

George P Marshall

Vincent Wen-Hwa Ting

John Joseph Earley

Albert Mann Carter, Jr

Joseph Edward Johnson

Minerva Piffarerio

Ronald James Whildin

Walter Mychajlowski

The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In particular, the crash cooling process involves the addition of a toner slurry having a temperature between 70&#xb0; C. and 90&#xb0; C. to an equivalent amount of cold water having a temperature between 5&#xb0; C. and 20&#xb0; C. Polyester and styrene acrylic toners as well as polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this cooling process results in an improvement to the amount of toner waste, thereby achieving a higher toner usage efficiency for an electrophotographic printing system.

Crash cooling method to prepare toner

The present disclosure relates generally to a method to make a chemically prepared toner that employs a crash cooling process. In the crash cooling process, an amount of hot toner slurry is added to an external reactor holding an amount of chilled cooling water, wherein the temperature of the chilled cooling water in the external reactor is from about 8&#xb0; C. to about 25&#xb0; C. The amount of the chilled cooling water in the external reactor is about 10% to about 40% lower compared to the amount of the added hot toner slurry. Toner prepared using this crash cooling method is cooled at a rate of less than 0.8&#xb0; C./min. Polyester toners and polyester core shell toners having a borax coupling agent between the toner core and toner shell made from this crash cooling processes using less water results in an improvement to the toner's print density and usage efficiency.

A chemically prepared toner composition according to one example embodiment includes a core including a first polymer binder, a second polymer binder, a colorant and a release agent; a shell that is formed around the core and includes a third polymer binder; and a borax coupling agent between the core and the shell. The first and third polymer binders are different amorphous polyester resins. The second polymer binder is a crystalline polyester resin and acts as a plasticizing agent in the core. The borax coupling agent assists in adhering the shell to the outer surface of the core. Optionally, the toner of the present invention may be finished with a set of extra particulate additives.

Chemically prepared core shell toner formulation including a borax coupling agent and a plasticizing agent in the core

A toner formulation is disclosed comprising a binder and an IR absorbing black pigment at a concentration of 0.25-2.0% by weight, including one or more infrared transmissive pigments, wherein the infrared transmissive pigments are configured to provide a black color. Such toner formulation may provide a response to a toner patch sensor to indicate a mass per unit area of 0.1-1.5 mg/cmor a reflectance relative to a substrate to define a reflectance ratio that varies relative to L* values for the toner over the range L*=0-50 or a bulk reflectivity of greater than 6.0% for a portion of the wavelength range of 850-2000 nanometers.

Black toners containing infrared transmissive and reflecting colorants

The present disclosure relates to a process for producing a toner particulate composition from aqueous dispersions containing aggregates of a polymer binder and other toner ingredients. An ionic surfactant may be used to form the dispersion along with an ionic polymer flocculent wherein the ionic polymer flocculent undergoes a molecular conformational change, which may be triggered by pH adjustment, leading to flocculation and particle growth.

Ionic polymer flocculants for the preparation of chemically processed toner

Toner is rounded by vigorously mixing less than about 5 percent by weight of particulate silica to the total weight of a starting toner in a closed, recirculating air system. The starting toner contains at least about 4.5 percent by weight of the starting toner of a wax and additionally contains at least 5 percent by weight of the starting toner of a softening agent. The temperature during the mixing is no more than 13 degrees C. above the onset of the glass transition temperature of the starting toner. The final toner comprises rounded starting toner having particulate silica embedded during the mixing process.

Closed air circulation toner rounding

Growing community of inventors

Johnstown, CO, United States of America

Trent Duane Peter