Self-adhesive envelope

Natural rubber Not "sticky enough" by itself Self-adhesive envelopes and other... 

Adhesive Coating of Paper and Board. Pressure-sensitive coatings, for example, for self-adhesive labels and envelopes include natural rubber-resin combinations in solvents, polyacrylate emulsions, and hot-melt adhesives. Polyacrylate emulsions and hot-melt adhesives are becoming increasingly significant because they are solvent-free. 

Formulation I at the end of this chapter is a suitable base. Preservation against bacterial attack is necessary, as also is a fungicide, as the dried film is open to the atmosphere. Zinc di-ethyldithiocarbamate performs both functions. It is sometimes found that an occasional batch of latex does not display a sufficient degree of self adhesion, and this may be overcome by adding a small amount of a high molecular weight plasticizer. A liquid polybutene added up to 10 pphr as a 50% emulsion is suitable. In some cases it may be necessary to improve the bond to the paper so that the envelope may not be opened without tearing the paper a polyvinyl acetate latex added at about 10 pphr has been found to achieve this without noticeable loss of self tack. 

Envelope sealing adhesives are usually remoistenable, and typically blends of dextrin and compatible polyvinyl aeetate homopolymers as well as all dextrin or all resin types. Some water-borne and hot melt pressure sensitive adhesives based on acryhc or rubber resin liquids and rubber resin hot melts are also used. Natural rubber latex is the basis for self sealing envelopes. 

Nonvulcanizing natmal rubber latex adhesives widi taekifiers have been used for self-adhesive envelopes, floor tiles, leather applieations, and the... 

This mechanism of adhesion advanced and originally promoted by the Soviets (1963) is of the greatest importance to applications where a material is being adhered to itself, such as in the self tack of rubber. Another familiar example is the application of the same adhesive to two diflerent surfaces from a solvent system, allowing the solvent to dry partially or totally, and then comhining the treated surfaces, such as in the use of contact cement or self-sealing envelopes. 

MacKenzie, R., Newman, D., Burger, M.M., Roy, R., Kuhns, W. J. Adhesion of a viral envelope protein to a non-self-binding domain... 

Natural rubber adhesive, or latex, is used in self-seal applications, where it makes use of its unique ability to bond only to itself with pressure. Applications include selfseal envelopes, press-to-seal cases, and cold-seal candy wraps. Natural rubber latex is also used in adhesives for lamination of polyethylene film to paper, such as in multiwall hags. 

Coating and binding products used for carpet backings, adhesives, adhesive tapes, self-seal envelopes, etc. 

Natural rubber has an excellent flexibility, high initial tack, and good tack retention properties. Typical applications include its use as an adhesive in self-sealing envelopes, and, in general, as pressure sensitive adhesive. It also has wide applications in the footwear and upholstery industries, for the attachment of leather, fabrics, and ruhher to one another or to wood and metal, bonding of paper, felt and textiles in the manufacturing of stationery, packaging, etc. 

Rubber-based solvent cements are adhesives made hy combining one or more rubbers or elastomers in a solvent. These solutions are further modified with additives to improve the tack or stickiness and the degree of peel strength, flexibility, and the viscosity, or body. Rubber-based adhesive is used in a wide variety of applications, such as contact adhesive from plastic laminates used for counter tops, cabinets, desks, and tables. Adhesive is used on pressure-sensitive tapes as floor tile adhesive and carpeting adhesive. Self-sealing envelopes and shipping containers use rubber cements. Solvent-based rubber adhesives have been the mainstay of the shoe and leather industry. 

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