Transfer tapes

In transfer tapes, the PSA is coated on the release liner without additional backing. Therefore the release forces on both sides of the liner have to be precisely different and constant over storage time. The adhesives sometimes contain short-cut glass fibers to decrease the elongation during unwinding. Such tapes are used to transfer the PSA to extruded profiles or other parts to endow them with pressure-sensitive adhesion. For use in household and office, special dispensers are available. 

Producers and Trade Names Avery-Dennison Corporation (Fas tapes), Beiersdorf (tesa tapes), MACtac, 3M (Scotch tapes), Scapa Tapes Klebetechnik (Cellux). 

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In conventional tenter orientation, the sequence of steps is as described above (MD—TD). In some cases it is advantageous to reverse the draw order (TD—MD) or to use multiple draw steps, eg, MD—TD—MD. These other techniques are used to produce "tensilized" films, where the MD tensile properties are enhanced by further stretching. The films are generally unbalanced in properties and in extreme cases may be fibrillated to give fiber-like elements for special textile appHcations. Tensilized poly(ethylene terephthalate) is a common substrate for audio and video magnetic tape and thermal transfer tape. 

Fig. 18. Transfer tape use in membrane switch assembly. (On right liner is removed, leaving die cut PSA ready for placement of laminate on the left.)...

Common applications for transfer tapes include the assembly of membrane switches used in the electronic industry, the attachment of face plates to appliances and other equipment, the assembly of automotive displays in the in.strument cluster, and the assembly of displays, such as touch screens for computers and teller machines. Fig. 18 pictures the use of a transfer tape adhesive in the assembly of a membrane switch. 

Like transfer tapes, reliable label performance will very much depend on the... 

Release coatings are important components of pressure sensitive adhesive (PSA) products such as tapes and labels [1]. Release materials are coated onto the backside of PSA tape backings (often called low adhesion backsizes or LABs in this form) to provide the desired tape roll unwind force. They are also coated onto various substrates to form release liners for PSA products such as labels and transfer tapes. Typically the thickness of the release coating is less than 1 p,m, and often times less than 0.1 jLm. Release coatings can be thought of as the PSA delivery system, providing a controlled unwind or release force and protecting the adhesive from contamination and unintentional contact until it is applied. 

This is a one step economical process for selectively transferring a high quality image to a plastic product. A heated die transfers the pattern from selected transfer tape to a flat plastic surface. Lettering or decorative designs can be transferred in pigmented, wood grain, or metallic finishes. 

Pressure-sensitive adhesives may also be coated directly onto release paper in order to produce transfer tapes, in which, as the name implies, the adhesive film will transfer from the release coating onto a substrate with which it is brought into contact. This permits exact placement of accurately controlled quantities of adhesive. Great care must be exercised in the choice of release paper to ensure successful application. 

Many commercially available office or packaging tapes and commercial blue tapes made double-sided sticky with adhesive transfer tape on the nonsticky side are not suitable. The adhesive on these tapes is usually not homogeneous. 

For completeness, it should be mentioned that there are adhesive transfer tapes. The adhesive layer is protected by two removable liners. This transfer adhesive may be a choice if very thin channels are required not allowing for accommodation of a double-sided adhesive tape with a stabilizing polymer substrate between the two adhesive layers. Transfer adhesive tapes can also be used for self-made double-sided adhesive tapes with a nonstandard substrate material. 

Unifilm, Unsupported pressure-sensitive transfer tape, Scapa Tapes North America... 

Many commercially available office or packaging tapes and commercial blue tapes made double-sided sticky with adhesive transfer tape on the non-sticky side are not suitable. The adhesive on these tapes is usually not homogeneous, i.e. it forms islands resulting in leaks when the glass chip and the thermoplastic fluidic scaffold are bonded together. Further, these tapes tend to make poor contact with low-energy surfaces (thermoplastics). 

Double-sided tapes generally consist of a carrier with adhesives on both sides and an intermediate release liner, to prevent contact of the adhesive layers when the tape is wound into a roll. There are also transfer tapes without carrier and tapes without release liner. 

Glass and polymer fibers are used to decrease strain under the influence of unwinding stress in unsupported double sided tapes (transfer tapes). 

Small pieces of rubber are cut from the ASTM sheets using a razor blade and placed in aluminium crucibles for direct mass spectral analysis. El and Cl spectra were acquired by using the same MAT 311A instrument with the conditions as described above. Spectra were acquired as the probe was heated from 50 to 300°C. For direct FAB analysis, the vulcanizates were cut into strips (8x3x2 mm) which were attached to the stainless steel FAB probe with scotch 924 transfer tape. The experimental conditions for FAB were the same as described above (no FAB solvent was used with the samples). 

PSA are widely used to attach labels and decals. They are increasingly used for trim bonding, particularly in the form of two-sided tapes or transfer tapes. New PSA show good adhesion to polyolefin-based substrates. 

Unbacked, two-sided tapes can be adhesive alone or, more commonly, two adhesive layers with a central core reinforcement layer of paper, fabric, or foam. These are commonly called transfer tapes, and are used in a variety of product assembly applications in industry and around the home. 

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