Spray adhesive

Spray adhesive is another application format rather than a single chemistry. Most aerosol products deposit a thin solution of rubber or resin while propellant and solvent flash off. Water-based bulk sprays and pressure-sensitive repositionable grades also exist. The family therefore has mixed cure behaviour and a wide spread of strength and heat resistance. The useful feature is fast, even coverage over a large area with little soak-through when the product suits the material. It is best for paper, card, fabric, foam, insulation, foil and lightweight laminates. It is usually bad for a small high-load joint because the film is thin and overspray is hard to control. Follow the pattern, distance and coat weight on the can. Some products bond while wet; others need both faces sprayed and allowed to become tacky like a contact adhesive. Missing that window gives either trapped solvent or a dry, weak film. Mask surrounding areas and protect the floor. Foam, flexible vinyl, plasticised materials and printed surfaces need testing because solvents can attack them or plasticiser can weaken the bond. A permanent label on one can does not make all spray adhesive structural or heat-resistant. For headlinings, upholstery and vehicle interiors, use a grade with a suitable temperature rating.

Mounting paper, card and photographs where the grade is photo-safe; laminating fabric, foam, foil and lightweight sheet; fixing insulation and acoustic material; temporary positioning with a repositionable grade; broad-area craft and display work.

Remove dust and grease, and mask well beyond the joint. Shake the can for the stated time. Test foam, vinyl, printed ink and delicate fabric. Hold the can at the specified distance and overlap passes evenly. Observe whether the product calls for one or two coated faces and wait the stated tack time. Use a roller or firm pressure to remove trapped air.