Backing for pressure sensitive

When produced as a thin film, it is often used in tape applications such as the carrier for magnetic tape and as a backing for pressure-sensitive tapes. 

Paper is a widely used backing for pressure-sensitive adhesive tapes. It is more expensive than simple plastic films but has several advantages. It is easy to tear by hand, tear strength is sufficient for many applications, it does not soften at high temperatures, and it can be upgraded by coating or saturating with polymers. 

Release Paper n A layer of paper which can be readily separated from the surface of a plastic article to which it has been applied or against which the plastic article has been formed. The term applies to papers used to protect the surfaces of plastic sheets, to temporary backings for pressure-sensitive adhesives, and to papers used as temporary carriers in film- and foam-casting processes. See also Transfer Coating. 

A variety of standard and specialized applicators exist for pressure-sensitive labeling. Standard portable head applicators provide top, side, and bottom labeling. These applicators use one of several basic methods available for application of automatic pressure-sensitive labels. In a tamp-blow method of application, the label is dispensed from the backing web and held in position by vacuum on a tamp pad. The tamp pad is indexed 0.8-1.5 cm away from the product, and then the label is applied to the product by a gentle blast of air. Tamp-blow applications are used for a large array of packages that have irregular, curved, or recessed surfaces. 

Tapes may be classified according to application areas, sueh as eleetrical, packaging, or medical, or in terms of the type of tape, usually defined by the backing, which may be paper, fiber, film, foil, or foam. Figures drawn from various tables produced by the Fredonia Group Inc. and published in Adhesives Age in June 1991 and the Frost and Sullivan Report, The USA Market for Pressure Sensitive Adhesives, in Adhesives Age in August 1991 showed that of a total U.S. pressure-sensitive adhesives market in 1989 of 4.9 billion, 2.6 billion was for sales of pressure-sensitive tapes. Table 6 illustrates the relative importance of the various backings and application areas. 

Uses Surfactant, emulsifier for latex or paper coatings, carpet backings, textiles, pressure-sensitive adhesives, esp. S/B, styrendacrylic, and acrylic emulsion polymer systems... 

Cellulosics. CeUulosic adhesives are obtained by modification of cellulose [9004-34-6] (qv) which comes from cotton linters and wood pulp. Cellulose can be nitrated to provide cellulose nitrate [9004-70-0] which is soluble in organic solvents. When cellulose nitrate is dissolved in amyl acetate [628-63-7] for example, a general purpose solvent-based adhesive which is both waterproof and flexible is formed. Cellulose esterification leads to materials such as cellulose acetate [9004-35-7], which has been used as a pressure-sensitive adhesive tape backing. Cellulose can also be ethoxylated, providing hydroxyethylceUulose which is useful as a thickening agent for poly(vinyl acetate) emulsion adhesives. Etherification leads to materials such as methylceUulose [9004-67-5] which are soluble in water and can be modified with glyceral [56-81-5] to produce adhesives used as wallpaper paste (see Cellulose esters Cellulose ethers). 

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. 

Way back in 1968 Dr. Silver was working for 3M on pressure-sensitive adhesives. These are glues that bond instantly to a surface but can be removed without destroying that surface. Today we are very familiar with such products peel-off stickers are everywhere. In 1968, however, they were virtually unknown. Scientists did realize that certain polymers, like natural rubber, could be peeled off under the right conditions, but they were not ideal. So Silver went to work. He investigated various synthetic polymers and eventually came up with one that was a weak adhesive and could be pulled off a surface. The difficulty was that it would not always pull off cleanly, and Silver lost interest. 

D 2686 Specification for Polytetrafluoroethylene Backed Pressure Sensitive Electrical... 

Pressure-sensitive adhesives are used for labelling applications. They are permanently tacky and adhere to the surface of the desired substrate under pressure. A paper or plastic film label is coated with a pressure-sensitive adhesive and applied to a backing layer - usually siliconised paper from which the label can be removed easily. The labels are then printed and sent... 

Batteries are typically produced with deep drawn metal cans on which a pressure sensitive adhesive label is applied for product identification, branding and safety information. Customers began complaining of batteries becoming jammed in various types of equipment. Devices returned to the manufacturer showed that the pressure sensitive labels had peeled back, resulting in adhesion between the overturned label and the device. Further examination of batteries on store shelves for more than a year also indicated peeling labels in a low frequency of batteries. These labels consisted of laminates of paper and polyester. The labels are normally flat and stiff and when applied over a battery, the labels will return to the flat condition if the adhesive fails. This results in peel-back at the edges of the label. 

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