Publishers of technical books and magazines yesterday filed a copyright-infringement lawsuit against Texaco Inc., charging the giant oil company with "large-scale, covert, unauthorized photocopying" of protected material.

The publishers did not ask for a specific amount of damages, but the case could cost Texaco millions of dollars in damages. The publishers asked a federal court to award them the maximum permitted under the law in cases of "willful infringement" of copyright restrictions: $50,000 for each incident.

The lawsuit, filed in U.S. District Court in New York, claims Texaco's research department routinely and secretly uses copyright material photocopied from books and periodicals such as the Journal of Polymer Science and the Journal of Rheology.

The suit opens a new front in the publishers' long legal battle against the photocopying machine. In previous cases sponsored by the Association of American Publishers, publishing companies sued universities and pharmaceutical companies -- which, like oil companies, are major consumers of research material -- and won settlements that the publishers then used as models for other agreements.

Texaco knew of these settlements and agreed to abide by them but did not do so, according to a spokesman for the publishers.

A spokesman said Texaco would have no comment until its attorneys had studied the legal papers. A company official said, however, that signs are posted at photocopying machines in Texaco offices reminding users of the requirement to observe copyright laws.

The publishers who sued yesterday are the American Geophysical Union, Elsevier Science Publishing Co. Inc., Pergamon Press Ltd., Springer-Verlag & Co., John Wiley & Sons Inc., and Wiley Heyden Ltd., of England. They asked the court to certify their case as a class action, which would make them the representatives of some 600 publishers whose material they say Texaco has used without authorization.

All the publishers are members of the industry's Copyright Clearance Center in Salem, Mass., which is authorized to grant reprint permissions on behalf of all the publishers to users who pay either a one-time fee or an annual fee covering all material. They said that Texaco agreed to cooperate with the center but has made only "token payments."

Townsend Hoopes, president of the Association of American Publishers, said in a statement that "major businesses that either make no effort to obtain clearance for their photocopying from scientific and technical journals or, like Texaco, make only token payments, must understand that publishers will not remain silent regarding violations of their copyrights."

The publishers said Texaco not only maintains a library of technical material reproduced without authorization, but also "regularly requests that libraries, owners of other collections and others make and deliver to it copies of materials from scientific and technical journals for distribution . . . to its employes for use in the course of their employment."