Лако-красочные материалы — производство

Recommended use temperature for dry animal glues and compounded products (except liquid glues) in most applications is 140 to 145°F (60 to 63°C). A range of 135 to 155°F (57 to 68°C) is acceptable but not preferred. Use at lower temperatures results in undesirable properties such as high viscosity, poor machinability, excessive glue use, and […]

Liquid animal glues are modified dry glue solutions containing a gel depressant, usually urea, thiourea, ammonium thiocyanate, or dicyandiamide, so that they remain fluid at and somewhat below room temperature. Liquid animal glues can be modified with clays or calcium carbonate as fillers, and wetting and dispersing agents, plasticizers, and other modifiers as required. Solids […]

Flexible and nonwarp glues are compounded animal glue-based products available in cake or dry blend form. Flexible cake glues are formulated to provide a permanent, flexible, resilient film. Glycerine is normally the primary plasticizer and may be modified with sorbitol and other glycols. Higher grades of animal glue are normally used to provide film strength […]

Since dry and compounded animal glues are used over a wide range of dilutions from 1% or lower to over 50%, no general ratio can be given. Dry glues are generally available in coarse (10 to 30 mesh) or fine (30 mesh and finer) granulation. Powdered glues (100 mesh and finer) are also available for […]

Animal glues are graded on the basis of gel strength (an arbitrary measure of the gelling property) and viscosity, which increases with an increase in gel strength. These properties have a marked bearing on glue application and end use. One of the earliest grading systems was introduced by Peter Cooper about 1844, establishing a basis […]

Commercially available animal glues are sold in granular or pulverized form, and are dry, hard, odorless materials that vary in color from light amber to brown. Animal glues may be stored indefinitely in the dry form. The density of animal glues is approximately 1.27. A moisture content of 8 to 15% is considered commercially dry. […]

Basic manufacturing procedures for animal glues generally involve alkaline pretreatment (for hide glues) or acidic pretreatment (for bone glues). The raw materials for hide glues include salted, limed, or pickled hide trimmings or splits, and chrome-tanned leather scrap. Tanned leather scrap requires special processing because of the chrome tannage. Hide glues from hide trim and […]

There are two major types of animal glue, hide glue and bone glue, differing in the type of raw materials used. Although process conditions may differ, both are obtained by hydro­lysis of the collagen in the hide and of connective tissue or bone structure of the raw material. Both types are principally of cattle origin […]

Animal glues are derived by the hydrolysis of the protein constituent collagen of animal hides and bones. Collagen in its natural state is water insoluble and must be conditioned to solubilize the protein. Collagen molecules are triple helices of amino acid sequences and contain both nonpolar and charged acidic and basic side chains. The conversion […]

Charles L. Pearson Swift Adhesives Division, Reichhold Chemicals, Inc., Downers Grove, Illinois, U. S.A. I. INTRODUCTION Animal glues have been used for thousands of years in traditional adhesive and sizing applications. In later times, they also found uses as protective colloids, flocculants, coat­ings, in composition, and as a component of compounded adhesives. The earliest known […]