Лако-красочные материалы — производство

During the early 20th century, the 3M Company (St. Paul, Minnesota, USA) developed the world’s first adhesive tape designed specifically for masking purposes in automobile body shops. Today’s applications (masking, fastening, bundling, decorating) of most different varieties of adhesive tape are as manifold as the material combinations and resulting properties. The wide spectrum of adhesive tapes features a variety of backings (paper, polyester, polyurethane, coated fabrics, cellophane, PTFE, aluminum or PVC; see Table 8.4), incorporating many adhesives, colors, widths and lengths.

Three different types of adhesive are employed in industrial adhesive tapes, each with its own advantages and disadvantages (Table 8.5).

Adhesive Tapes with Paper Backings This group of products comprises adhesive tapes basically used for reinforcing, closing, splicing, masking during painting, and for belt applications.

Adhesive Tapes with PVC Backings Adhesive tapes with PVC backings have a wide field of applications owing to their high performance. Indeed, they are resistant to solvents, possess a high quality of color, can be stretched, and are resistant to abrasion. They are used for closing, marking and labeling, protecting, masking, bundling, fastening/tacking, and for many other purposes.

Adhesive Tapes with Polyester Backings Tapes with polyester backings are used for fastening, processing web materials, protecting and covering. They possess high

resistance to aging, high tensile strength, and excellent resistance to chemicals and abrasion. They are available as colored or transparent tapes, and have a temperature performance between —50 °C and +180 °C.

Adhesive Tapes with Metal Backings There is no easier, faster or cleaner way to process metals. Metal backings possess excellent resistance to aging, and resis­tance to high — if not the highest — temperatures. Furthermore, they are very resistant to solvents, show low water-vapor permeability, and are suitable for die cutting.

Sliding Tapes Sliding tapes are based upon PTFE and ultra-high molecular weight (UHMW) PE, and have special properties. Both offer a high resistance to tempera­tures and the lowest coefficient of friction. UHMW PE tapes were specifically designed to have a high abrasion resistance. PTFE tapes have the following properties:

• low coefficient of friction (the ‘self-lubrication effect’ of PTFE adhesive films improves the processability of web materials)

• excellent heat resistance (PTFE glass cloth tapes with high resistance to elevated temperature provide longlasting performance on many heat-sealing machines)

• anti-stick/release effect (facilitates clean-up of hot plastic extrusion coating by not allowing plastic build-up on rolls)

• resistance to chemicals (PTFE tapes provide a chemical barrier in production sectors with high exposure to chemicals)

• conformability (PTFE tapes provide for easy use and effective service of rolls)

The important properties of UHMW PE tapes are:

• abrasion resistance (UHMW PE tapes are used to protect the plastic or metal surfaces of conveyor belts, guide rails and containers from wear)

• noise damping (efficient damping of noise and vibrations in many fields of application)

• anti-stick/release effect (provide for easy clean-up of components/surfaces because sticky materials such as paints, adhesives or varnishes do not adhere to UHMW PE tapes)

Cloth Adhesive Tapes Cloth adhesive tapes and special tapes made from aluminum and/or glass cloth have a wide field of application owing to their coated cloth backing, in combination with adhesive varieties. They offer high tensile strength (glass cloth backings have an unmatched tensile strength that is seven times higher than that of polyester backings) and high resistance to elevated temperatures.

Adhesive Tapes with Polyurethane Backings Polyurethane tapes comprise a perform­ing polyurethane backing coated with different types of adhesives on one side. Polyurethane tapes coated with acrylic adhesive are suitable for permanent bonding applications, and have very good resistance to solvents and UV radiation. Polyure­thane tapes coated with rubber-resin adhesives are employed for temporary bonding applications. The outstanding properties of such tapes include excellent abrasion resistance, optimal protection against erosion, excellent tensile and disruptive strength, and good printability.

Adhesive Tapes with Cellulose Acetate and Cellophane Backings These tapes possess high transparency and resistance to aging, and are used mainly for the splicing of film footage, for closing, covering and protecting, tacking and marking purposes.

8.6.3