Glues of Animal Origin

Animal glue is the primary adhesive component in gummed tapes used in sealing commercial solid fiber and corrugated shipping uses, as well as the more common lightweight types used in retail packaging.  

Shellacs are thermoplastic resins derived from insects. They are used in alcoholic solutions or as hot-melt mastics. They have good electrical insulating properties but are brittle unless compounded with other materials. 

Shellacs are resistant to water, oils, and grease. Bond strengths are moderate. Shellacs are used to bond porous materials, metals, ceramics, cork, and mica. They are also used as adhesive primers for metal and mica, for insulating sealing waxes, and as components of hot-melt adhesives. Shellacs are the basic components of de Khotinsky cement. Their application has declined over time because of their high cost.  

Shellac is used as an alternative to alkyd resins in binding mica splitting to produce mica board. This is pressed into shapes used as insulation in electric motors, generators, and transformers. Mica tape, used as insulators in motors and generator coil slots, is fabricated by bonding mica flakes to glass cloth and tissue paper with shellac or silicones.  

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Glues of animal origin are very prone to biodegradation and will fail rapidly in hot damp conditions. 

Solutions of natural and synthetic high molecular mass substances in water, e.g., starch, dextrins, casein, cellulose ethers, water-soluble derivatives of poly(acrylic acid), poly(vinyl alcohol), poly(vinyl pyrrolidone) (adhesive sticks). Uses paper, fiberboard. Glutins (glues of animal origin). Uses wood, paper, fiberboard, moistenable adhesive tapes. 

Animal (Colla) Impure gelatinous mattet of animal origin, most commonly bone glue made from hides and bones, casein glue made from skimmed milk, and fish glue made from fish skins [Hackh s... 

Products of animal origin animal glues, casein... 

Animal glues are usually made from bones and hide. Casein from milk and fish glues are also of animal origin. 

From antiquity, glues had been made almost entirely from materials of animal or vegetable origin, and were sensitive to moisture, oxidation, and bacterial or fungus attack. Because of these deficiencies, production of durable plywood, for example, was not possible. The modern plywood industry actually owes its growth to the availabiUty of relatively low cost urea adhesives. Plywood and chipboard or wood chip glues are often made at the plywood and chip board mill. 

Plant Resin Formulations, Sometimes compounded with shellac, as in DeKhotinsky cement, these compounds have long been used as hot-melt glues. Likewise, waxes of plant and animal origin have also been used as hot-melt adhesives (22). They all should be reversible by application of heat, possibly in conjunction with solvent action in the more diflScult cases. 

Glue, n—Originally a hard gelatin obtained from hides, tendons, cartilage, bones, etc. of animals. Also, an adhesive prepared from this substance by... 

Glue, n Originally, a hard gelatin obtained ftom hides, tendons, cartilage, bones, and so on of animals. Also, an adhesive prepared from this substance by heating with water. Through general use, the term is now synonymous with the term adhesive. However, the term is most commonly used for wood adhesives. 

Adhesives of natural origin were mainly used prior to the beginning of the 20th century and by early civilizations as long ago as 2000 BC. These included animal glue, casein, natural rubber and starches. Today, specially developed adhesives based on semi- or fully synthetic products are used for a wide variety of bonding applications (Fig. 8-1). 

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