WALLPAPER IS fast becoming wall-vinyl, according to Candace Johnston. She could be prejudiced -- she's a designer and consultant for wall-covering manufacturer Vicoa Inc. It does appear that vinyl coverings are threatening to take over now that, as Johnston notes, "the plastic look is gone." Wallpaper has been on the want for the last decade; paper-backed vinyl and canvas-backed vinyl as well as vinyl-coated paper have almost totally replaced it, says Phyllis Bernstein, interior designer for Decorator Showroom, 4350 East-West Highway in Bethesda. "We make very few [uncoated] wallpaper sales these days," says Bernstein. "Wallpaper is just what it says, paper. And like paper, it tears, yellows and cannot really be washed without damage being done to it. It makes sense for consumers to turn to vinyl."

"Consumers are quite knowledgeable about what they want these days," says Henry Bolter, executive vice president of Capital Asam Inc., a wall-coverings distributor. Bolter, who's been in the wall-covering business for more than 40 years, says that although vinyl entered the wall-coverings market in the late '50s, it "really didn't make an impact until the '70s and '80s."

Keith Byrd, store manager for Duron Paint and Hardware Store in Silver Spring, says vinyl wall-covering sales are definitely up. "We still get some orders for wallpaper but mostly from older folks who grew up with paper. Some people just don't like to change."

Of course many fine and expensive wallpapers are still available -- Scalamandre and Louis Bowen, both of New York, are just two paper manufacturers who are doing quite well, according to Suzanne Shaw of Suzanne Shaw Interiors, 2825 48th St. NW.

Shaw, herself, admits, "I still love the look of wallpaper, but the majority of my customers buy the vinyl. I tell those customers who prefer wall-paper about the new Scotch-gard type coating called ResiStain. It's a chemical substance that can be applied to wallpaper by the manufacturer at the time the customer places his order. It makes the paper washable -- though not scrubbable."

Jean Benham, interior decorator and president of Small Spaces likes vinyl wall coverings because "redoing a room with wallpaper used to be such a chore. To remove the old paper you had to rent a steamer to steam it off -- and even that didn't always work." Or, as another expert suggests: "Wet the paper off the wall," (from "420 Ways to Clean Everything" by Harriet Wylie).

"With many vinyls," says Benham, "all you have to do is pull or peel them off." To put up one of the new coverings, apply a pre-mixed paste to the back side of the covering. Let it set for about four minutes. Then put the covering on the wall with a latex roller.

"The vinyls are also easier to hang," adds Benham. "They're more durable and don't lose their shape once they're dampened. Once a vinyl wall covering is put up, you can fanagle it until you get it in just the right position. With wallpaper you should really apply it as perfectly as possible to start with. Playing with it to make it fit can ruin it."

Not surprisingly, vinyl wall covering is much preferred by wallpaper hangers. One wall-covering hanger says his company tries to avoid a wallpaper job when possible. Another, Kenneth Spohn of the Edward W. Minte Co. says, "You seldom see a wallpaper job anymore -- although it does look nice. Vinyl lasts longer and wallpaper takes so long to hang - usually a day longer than a vinyl job."

"Vinyl wall coverings are also longer lasting than paint," says Capital Asam's Bolter. "Paint shows wear -- alter a year and a half, you have to repaint. People usually replace vinyl or paper coverings after five or seven years, not because it's wearing but because they're tired of it. Like buying a new dress -- even if the old one is in good condition, you want a new style, color . . ."

Time-consuming wallpaper-cleaning recipes, such as "remove grease spots by placing a piece of clean blotting paper over the mark and press with a warm iron; repeat until the spot has gone," are no longer necessary with vinyl.

To clean vinyl wall coverings, says Johnston, a sponging with a mild detergent will do or, "if the spot is stubborn, try scrubbing with baking soda and warm water -- about a half-cup soda to one gallon water."

Prices for wallpaper and vinyl wall covering vary. Designer vinyl wall coverings run as high as wallpaper prices -- from $25 a roll to as high as $80. cBerstein of the Decorator Showroom, says "the paper-backed designer lines are handmade silk screen prints for which the manufacturer charges as much as, and often more, for the more delicate wallpaper." The designer vinyls are at least twice the price of the maching-printed canvas-backed vinyl wall coverings, which run about $10-$20 per roll. Designer paper runs about $35 per roll, while machine-printed paper starts at about $15.

Joan Smith, a sales representative for B. F. Goodrich, another manufacturer of vinyl wall coverings, points out that the price of vinyl coverings is greatly affected by the price of oil. "One of the main ingredients in vinyl is an oil derivative, known as PVC (polyvinyl choloride) resin. As oil increases in price, so do vinyl wall coverings." Smith recalls that during the 1974 oil crisis, the wall coverings were difficult to manufacture because of the scarcity of PVC resin. She points out that other factors, such as the increasing price of cotton used in the fabric backing of many of the wall coverings and the rising energy costs of running the production plant also contribute to the increased cost of vinyl wall coverings.

Very often the companies that make vinyl wall coverings also make color-coordinated fabrics to complement the coverings. Vicoa (eatontown, N.J.) has a new collection of coordianted coverings and cotton-polyester blend fabrics, called "Special Request." The plastic look of vinyl is disappearing. The new Vicoa collection resembles -- until you touch it -- the romantic, flower pattersn of popular fabrics. The new line of 40 separate designs (priced between $9.95 - $12.95 per roll) can be found at local paint and hardware stores, including Duron Paint and Hardware in Silver Spring, Md. (Duron also makes their own wall covering called "Potomac Wallcovering," which runs from $6.99 to $89 per roll.) Vicoa is also carried by Accent Wallcoverings, Green Wallpaper and Paint, as well as Decorator Showroom in Bethesda.

Wall-coverings manufacturer The James Seeman Studios of Garden City Park, N.Y., has a new collection of coverings and fabrics, called "Tessitura II." Tessitura includes 25 designs ranging from mini-prints and stripes and checks to delicate florals and Oriental-inspired motifs. Tessitura comes in 87 colors and with a selection of four companion fabrics in 15 colors. Tessitura is carried locally by Capital Asam Inc., Capitol Heights, Md.

Essex Wallcoverings of Glen Rock, N.J., (a subsidiary of the General Tire and Rubber Co.) has a new line of wall coverings called "The Eighties." This collection contains 41 patterns, emphasizing the elegant country look, in 143 colors of fabric-backed vinyl wall coverings with correlating fabrics. Locally carried by Union Wallpaper and Paint Co. in Rockville.

B. Berger of Cleveland, Ohio, puts out a coordinated wall covering and fabric collection as does Bob Mitchell of California. Both manufacturers are carried by Decorator Showroom.

Stores in this area that carry coordinating fabrics and wall coverings are Conran's and Laura Ashley, both in Georgetown.

Wall coverings are not limited to walls. As in the 17th century, you can glue them on your kitchen cannisters, waste baskets, even wrap gifts with them . . . Kitchens and bathrooms -- high spillage areas -- are especially good rooms to test your imagination.