SCIENCE/TECHNOLOGY : 2 Briefcase Computers Unveiled by Toshiba as Its Key 1992 Lines

Toshiba strikes back. A good name for a movie? Stay tuned.

After suffering from market-share erosion most of this year, computer maker Toshiba America in Irvine on Monday introduced two lines of briefcase-size computers that the company says will be its key products for the coming year.

“It is hard to stay No. 1 forever, but the real story is how does a company respond to market challenges,” said Grant Johnson, director of product marketing at the company’s computer division.

Toshiba has about 21% of the notebook-computer market, but it acknowledges that it has lost ground in the past year to scores of upstart companies entering the $1.4-billion notebook-computer market, such as AST Research Inc. in Irvine.

In December, the Toshiba division plans to ship its T4400SX notebook computer that weighs 7.5 pounds and has a speedy 486SX microprocessor, a chip that performs a computer’s basic processing and number-crunching functions, from Intel Corp.

The T4400SX can also be upgraded to the 486DX microprocessor, the Ferrari of all processing chips. The line, designed to provide a notebook computer with the same essential capabilities as a desktop machine with the exception of a color screen, is priced from $5,599 to $5,899, depending on the type of screen.

Toshiba will also introduce its T3300SL notebook computer, a lighter, 5.9-pound machine with an Intel 386SL microprocessor that is engineered especially for notebook computers. The machine, priced at $5,299, should be available in January.