Лако-красочные материалы — производство

William F. Harrington Adhesive Information Services, Mishawaka, Indiana, U. S.A. I. INTRODUCTION At first, there was only natural rubber, a substance “discovered” by Christopher Columbus on his second voyage to the New World. Soft and tacky when solidified from the tree latex, it remained a curiosity for many years, eventually finding use as a ‘‘rubber,’’ […]

Solid natural rubber is widely used in adhesive formulations for making electrical insula­tion tapes, packaging tapes, and surgical tapes and plasters. The backing may be made from paper crepe, cloth, or synthetic materials, depending on the application. The rubber can be applied from solvents or calendered directly onto the backing. The following formulations are for […]

Parts by weight (wet) 60% Natural rubber latex 167 50% Dispersion of zinc dibutylthiocarbamate 2 10% Solution of ammonium caseinate 10 2. Adhesives for the carpet industry. Formulations for backing carpets of hessian and polypropylene staple construction are given below. Parts by dry weight A:Primary B:Secondary backing backing 60% Natural rubber latex 100 100 Stabilizer/wetting […]

Latex adhesives are made from natural rubber latex by adding stabilizers, wetting agents, and other components. They are applied to the substrate by brush, spray, doctor knife, or reverse roll coater. The adhesive is dried to film near room temperature. The adhesive strength can be improved by vulcanizing the system. The applications of latex adhesives […]

Sadhan K. De Indian Institute of Technology, Kharagpur, India I. INTRODUCTION Natural rubber adhesives can be classified into two principal types: latex adhesives and solution adhesives. Natural rubber latex is obtained by tapping the tree Havea brasiliensis. The latex consists of about 35% solids. Ammonia is added to the latex immediately after the tapping to […]

Gums are hydrophobic or hydrophilic polysaccharides derived from plants or microor­ganisms that upon dispersing in either hot or cold water produce viscous mixtures or solutions. Natural gums include plant exudates (gum arabic, gum ghatti, gum karaya, gum tragacanth), seed gums (guar gum, locust bean gum, tamarind), plant extracts (ara — binogalactan from larch; agar, algin, […]

Adhesives for remoistening applications such as tapes, stamps, labels, and envelope flaps must be capable of rewetting. Such adhesives should also be glossy, noncurling, and nonblocking under humid conditions. This requires that the formulation contain acid — modified starch or high-soluble white and yellow dextrins to allow a high solids content. A plasticizer is added […]

Cartons from corrugated board are most often sealed with liquid glues or hot-melt adhe­sives. However, dextrin adhesives are still used as a result of their low cost and ready availability. Adhesives for sealing cartons must have low and stable viscosity, be able to form strong bonds, and set up quickly. If staining of the carton […]

Three types of adhesives are used in the manufacture of paper bags and sacks: side-seam adhesive, bottom paste, and cross paste. During production of a single-layer bag, the paper is first formed into a long tube held together by side-seam adhesive. To be compa­tible with machinery used in this process, the adhesive needs a viscosity […]

The majority of starch-derived adhesives are used in the paper and textile industries as binders and sizing materials. However, the discussion in this chapter is limited to glues and pastes, since paper and textile uses have been covered thoroughly elsewhere [12]. This section provides an overview of severa1 gluing applications, with specia1 attention to the […]