US PATENT SUBCLASS 528 / 308.5-- .~.~.~.~.~.~ At least two claimed distinct temperature or pressure gradients

US PATENT SUBCLASS 528 / 308.5
.~.~.~.~.~.~ At least two claimed distinct temperature or pressure gradients

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999 Terms of Use

528 /	HD	SYNTHETIC RESINS OR NATURAL RUBBERS -- PART OF THE CLASS 520 SERIES

*	DD	SYNTHETIC RESINS (Class 520, Subclass 1) {23}
271	DF	.~ FROM CARBOXYLIC ACID OR DERIVATIVE THEREOF {10}
272	DF	.~.~ From di- or higher ester of a polycarboxylic acid as sole reactant, or from a polycarboxylic acid or derivative with a compound containing two or more hydroxyl groups or salts thereof {15}
308	DF	.~.~.~ Aryl-containing carboxylic acid or derivative of an aryl-containing dicarboxylic acid {2}
308.1	DF	.~.~.~.~ Polyethylene Terephthalate per se {2}
308.3	DF	.~.~.~.~.~ Processes of preparing {2}
308.5		.~.~.~.~.~.~ At least two claimed distinct temperature or pressure gradients

DEFINITION

Classification: 528/308.5

At least two claimed distinct temperature or pressure gradients:

(under subclass 308.3) Subject matter wherein the process involves at least two distinct gradients, either temperature and/or pressure.

(1) Note. A temperature range, such as 273 deg.C - 283 deg.C or "a temperature less than 300 deg.C, "is considered to be one distinct gradient for this subclass. A temperature described as commencing at 273 deg.C and gradually being increased to 283 deg.C is considered to be "at least two distinct gradients" for purposes of this subclass.