Adhesive-Backed (PSA, Peel-and-Stick) Gasket Material

What peel-and-stick adds, and what it does not

A PSA lamination holds a sponge, foam, felt or thin rubber gasket on a door, lid, panel or housing while the assembly closes, and keeps it from falling out when the cover comes off for service. It is not the seal. The compressed gasket seals, and the adhesive only keeps it in place, so a gasket that leaks with adhesive leaks without it. The adhesive is put on by the sheet maker, and the gasket is cut from the laminated sheet with the liner still on.

The base sheet usually limits the gasket before the adhesive does. The cited acrylic holds 149 C long term and 204 C short term on steel [S1], but a neoprene sponge gives up long before that, so read the base sheet's own page for the service range. Where the base sheet runs hot or cold, silicone sponge with a silicone PSA is the usual pairing.

The three adhesive families

Every PSA on a gasket sheet is one of three chemistries, acrylic, rubber or silicone, and the choice follows the base sheet and the surface it sticks to. The cited acrylic, 3M's 200MP on 467MP and 468MP, holds 149 C long term [S1]. For silicone sheet, 3M's 9731-100 double-coated tape carries a silicone adhesive on one face, which bonds silicone rubbers and low-surface-energy plastics, and an acrylic adhesive on the other [S2].

Transfer tape, film-supported tape and foam tape

A transfer tape is adhesive alone on a liner, so the gasket keeps all of its flexibility; it is the usual lamination on foam and sponge. A film-supported (double-coated) tape carries the adhesive on a thin polyester film, which stops a soft, stretchy cut gasket from distorting as the liner comes off and holds its shape on installation. An acrylic foam tape is itself a soft, conformable core with adhesive on both faces, used where the tape must fill a gap as well as hold. The print names the construction when it matters; otherwise the sheet maker's standard lamination is quoted.

Bonding silicone sheet

PSA bonds by wetting the surface, so the surface decides the bond. Silicone sheet needs its own adhesive face: 3M's 9731-100 puts a silicone adhesive against silicone rubber and an acrylic adhesive against the other surface, and 3M lists silicone gasket bonding among its uses [S2]. Clean, dry surfaces and firm pressure at application matter as much as the adhesive; the 3M sheet reports the peel bond on steel still rising from 15 minutes to 72 hours of dwell [S1].

Ordering and cutting

Say which face gets the adhesive, or draw it, and name the tape if the print does. Adhesive-backed sheet is cut on the waterjet with the liner on, so each part arrives ready to peel and place. Kiss-cut parts that must stay on a continuous liner for hand or machine placement are not a waterjet job; they are cut by a converting partner and quoted from the same drawing, so say so on the request.

The foam and sponge sheets that most often carry a PSA face are compared on the foam gaskets page.