Paper pressure sensitive adhesive

Sihcone products dominate the pressure-sensitive adhesive release paper market, but other materials such as Quilon (E.I. du Pont de Nemours Co., Inc.), a Werner-type chromium complex, stearato chromic chloride [12768-56-8] are also used. Various base papers are used, including polyethylene-coated kraft as well as polymer substrates such as polyethylene or polyester film. Sihcone coatings that cross-link to form a film and also bond to the cellulose are used in various forms, such as solvent and solventless dispersions and emulsions. Technical requirements for the coated papers include good release, no contamination of the adhesive being protected, no blocking in roUs, good solvent holdout with respect to adhesives appHed from solvent, and good thermal and dimensional stabiUty (see Silicon COMPOUNDS, silicones). 

In the adhesives area, thermoplastic, fatty polyamides are used in hot-melt and heat-seal adhesives for leather, paper, plastic and metal. Blends of EDA- and DETA-based polyamides are suggested for use in metal can seam sealants with improved toughness (234) pressure sensitive adhesives have been formulated with DETA-based polyamides (235) and anionic and cationic suspensoid adhesives are used as heat-seal coatings in paper converting (236). PIP and certain PIP derivatives are used with EDA in some appHcations (237). 

A number of higher poly(vinyl ether)s, in particular the ethyl and butyl polymers, have found use as adhesives. When antioxidants are incorporated, pressure-sensitive adhesive tapes from poly(vinyl ethyl ether) are said to have twice the shelf life of similar tapes from natural rubber. Copolymers of vinyl isobutyl ether with methyl acrylate and ethyl acrylate (Acronal series) and with vinyl chloride have been commercially marketed. The first two products have been used as adhesives and impregnating agents for textile, paper and leather whilst the latter (Vinoflex MP 400) has found use in surface coatings. 

Pressure sensitive adhesives can be coated on a substrate such as a polyester or paper backing to make a tape or label, or on a release liner to make a transfer adhesive, or a special substrate to make a graphic film or retro-reflective sheeting product. In some cases, where precision placement of the PSA is required, one may also coat directly on the substrate using techniques such as screen-printing. 

A product is only considered to be totally biodegradable if all its single components can be degraded naturally. Currently, pressure sensitive adhesives (PSA) are mostly based on non-biodegradable synthetic polymers such as polyacrylates, ethylene-vinyl acetate copolymers and styrene block copolymers [124]. Therefore there is a growing demand for the application of biodegradable PSAs on naturally degradable products like paper and cardboard. 

Silicone release liners are used as a nonadhering surface to which adhesive materials, such as, for example, pressure-sensitive adhesives, can be laminated. UV curable release coatings are based on poly(dimethylsiloxane) oligomers functionalized with acrylate or epoxy groups and are mostly coated onto papers or thin films. 

Film Adhesive. A further type which is of importance commercially is the film adhesive which exists usually as pre-formed shapes on suitable substrate materials (often, siliconized release paper). When being applied, such adhesives are activated by heat or pressure and so converted into a semi-fluid condition, when they can wet the surface to be bonded. The pressure-sensitive adhesives are an example of this type—the application of finger pressure alone being sufficient to form the bond. 

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... 

There are two main types of coldseal adhesive and these are based on natural latex or synthetic polymers. They differ from pressure-sensitive adhesives in that they stick only to themselves. They are applied to form dry but gummy adhesive layers on flexible plastic films or paper and can be subsequently sealed together by pressure alone to form wrappers for food items and especially for confectionery. 

The primary mode of bonding for a pressure-sensitive adhesive is not chemical or mechanical but rather a polar attraction to the substrate. This always requires pressure to achieve sufficient wet-out onto the surface thereby providing adequate adhesion. The four main varieties of pressure-sensitive adhesives are derived from rubber-based, acrylic, modified acrylic and silicone formulations. Release liners are used to carry the sticky label and enable it to be printed. The release liners are normally paper, treated with a very thin silicone coating to allow the label to be peeled away easily without tearing. Some transfer of the silicone into the adhesive is inevitable. 

Organosilicone Coating Products. SiHcone products are used in a large variety of coatings appHcations most prominent among these are siHcone pressure-sensitive adhesives (PSA), plastic hardcoats, and paper release coatings (398,399). 

The release effect of silicones is put to use in baking paper or baking ware coatings, and pressure-sensitive adhesives release paper coatings. 

Silicone release coated papers and films, when laminated to pressure-sensitive adhesive (PSA) coated materials, such as adhesive coated labels and tapes, provide both protection for the adhesive coated product (such as in preparation for slitting, die-cutting, and the like) and they provide subsequent easy release of the release coated paper or film from the adhesive surface immediately prior to its intended final use... 

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. 

Use Tire carcasses and linings, especially for tractors and other outsize vehicles electric wire insulation encapsulating compounds steam hose and other mechanical rubber goods pond and reservoir sealant. Latex is used for paper coating, textile and leather finishing, adhesive formulations, air bags, tire vulcanization, self-curing cements, pressure-sensitive adhesives, tire-cord dips, sealants. 

Use Hot-melt and pressure-sensitive adhesives, mastics and sealants, varnishes, ester gum, soldering compounds, core oils, insulating compounds, soaps, paper sizing, printing inks, polyesters (formed by reaction of the conjugated acids of rosin with acrylic acid, followed by reaction with a glycol). 

Pressure-sensitive adhesives are the essential components of adhesive tapes and labels. They are polymers with permanent tack, usually applied on substrates (plastic/metal films, siliconized papers). To enhance their tack, compounds with high inherent tack are added, for example, resins, plasticizers. Pressure-sensitive adhesives reach their adhesion on the material to be bonded by contact pressure, from which the term pressure-sensitive adhesive (PSA) derives. Apart from electron radiation, also UV-radiation curing described in Section 4.3.2 is applied in adhesive tape manufacturing. The monomer molecules to be polymerized are applied, in liquid form, to the substrates to be coated by rolling and are continuously cured to a polymer layer within seconds under a UV-radiation source. Depending on their composition, predetermined adhesion values can be adjusted. The adhesive tapes can be subsumed under the systems shown in Figure 5.4 ... 

Depending on the formulation, permanent pressure-sensitive adhesives (e.g., for car tax vignettes, price-labels) or removable pressure-sensitive adhesives are available. In the past, so-called repositionable pressure-sensitive adhesives have gained special importance, which are mainly applied to papers used as multiadhesive memo sheets. 

A weight G (approx. 250 g) acts on a sheet of paper (on a smooth board). A paper coated with pressure-sensitive adhesive (Multi-adhesive memo sheets available at the stationery shop are best suited) is loaded by force F, according to Figure 11.2, drawing (a) (shear stress). It is possible to draw the paper sheet over the board with the weight on it. 

Adhesive tapes Consisting of plastic, plastic foam, metal, paper or textile tapes with or without reinforcement, coated with a pressure-sensitive adhesive layer on one or two sides. 

Other decorative boards home interior components water treatment plants pressure sensitive adhesives, papers and films pesticides health foods sweeteners special films. 

The backing material and release liner can be fabricated from a variety of materials including polyvinylchloride, polyethylene, polypropylene, ethylene-vinyl acetate and aluminium foil. The most important property of these materials is that they are impervious to both drug and formulation excipients. The most useful backing materials conform with the skin and provide a balanced resistance to transepidermal water loss, which will allow some hydration of the stratum corneum, yet maintain a healthy subpatch environment. The release liners are usually films or coated papers and must separate easily from the adhesive layer without lifting off any of the pressure-sensitive adhesive. Silicone release coatings are used with acrylate and rubber-based adhesive systems, and fluorocarbon coatings with silicone adhesives. 

Numerous papers, usually of the single face coated types, are now available with a wide range of pressure sensitive adhesives. These adhesives may be ... 

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