Maker of Foam Being Bought : Acquisition: Great Western Carpet Cushion in Orange will be owned by one of nation’s biggest polyurethane makers.

Polyurethane foam usually doesn’t elicit much notice, despite the fact that it’s everywhere--in mattresses, sofas, packaging, car seats.

That omnipresent substance has made Great Western Carpet Cushion Co. in Orange a success. In 1991, the foam manufacturer had revenue of $100 million and 600 people on its payroll.

Now the privately held company, one of the largest foam makers in California, is being bought by one of the largest foam makers in the country.

Foamex L.P., which boasts annual sales of half a billion dollars, on Wednesday announced an agreement to acquire most of the assets of Great Western Carpet Cushion. The purchase will give Foamex, based in East Providence, R.I., a chance to market its product on the opposite side of the continent, a feat that would be prohibitively expensive without a base here.

“We provide Foamex an immediate influence on the West Coast, and they provide us the advantage of being associated with a national firm,” said Brad DeCapite, chief financial officer of Great Western Carpet Cushion.

Shipping foam long distances is financially impractical, DeCapite explained: “It’s a light and bulky product, so it fills a truck very rapidly with air.”

DeCapite said he does not expect changes in personnel at Great Western Carpet Cushion, which has 300 employees at its Orange County plant and another 300 distributors and salespeople in Northern California and Washington state.

Foamex is carving out an agreement to buy another foam maker, General Felt Industries Inc. in Saddlebrook, N.J. It said it is purchasing both of the smaller manufacturers for a combined $137 million but would not give specifics of the individual transactions.

The company said it expects to complete the acquisitions during the first half of 1993.

Foamex is a subsidiary of privately held 21 International Holdings Inc. in New York, a $1.1-billion holding company whose interests include the 21 restaurant in Manhattan.