Лако-красочные материалы — производство

As with almost all commercially available high performance products on the market today, there are many proprietary, highly formulated products described as ‘‘acrylic adhesives.’’ The formulations vary widely with different families and subfamilies of products constantly being introduced, each offering certain advantages over previous “generations.” In general, however, they can all be characterized as having […]

Most acrylic adhesives are supplied as two high viscosity liquids or pastes that are mixed together, called ‘‘Mix-in Accelerator” systems. Some types can also optionally be cured by no-mix accelerator lacquers. Accelerators are low viscosity liquids which are brush or spray applied to one or both of the substrates being bonded. Following accelerator appli­cation, the […]

Like most adhesive types, acrylic adhesives do not have an indefinite shelf life after manufacture. Typically suppliers of acrylic adhesives list shelf lives of at least three months, with some as long as a year. One difference with acrylic adhesives is the fact that they do often contain large amounts of highly reactive substances (monomers) […]

Acrylic adhesives cure by addition polymerization reactions. These chain reactions are initiated by the formation of free radicals that result in the adhesive curing by way of a very rapid polymer chain growth. This cure chemistry is significantly more rapid than a typical cure curve (i. e., condensation type) found in epoxy and urethane adhesives. […]

Dennis J. Damico Lord Corporation, Erie, Pennsylvania, U. S.A. I. INTRODUCTION ‘‘Curing acrylic adhesives’’ can be defined as reactive, cross-linked, high strength structural adhesives that cure by way of free radical initiation. They typically contain methacrylate monomers that are generally toughened with elastomeric polymers as part of the formulation. Curing acrylic adhesives are distinctly different […]

Following are formulas for hot melts in various applications. Ingredients are listed in parts by weight. A. General-Purpose Hot Melts for Both Wood and Plastic Veneers White Natural Brown Hydrocarbon resin, 90°C m. p. 5.50 5.50 5.50 Rosin ester, 85°C m. p. 8.00 8.00 8.00 Coumarone indene resin, 105°C m. p. 5.00 5.00 5.00 Butylated […]

The single most important component on an edgebander is the gravure wheel applicator. All other components of the machine support the performance of the gravure wheel applicator. It is the gravure wheel application that controls the amount of hot-melt adhe­sive that is applied to the substrates, which, in turn, determines the number of calories of […]

Where a cartridge heater is mounted in the center of the applicator wheel shaft, a high- temperature grease must be used as a heat-conducting medium between cartridge heater and applicator wheel; otherwise, there will be rapid cartridge heater burnout due to over­heating. Adhesive temperature at the applicator wheel should be 12 to 13°C cooler than […]

A. Application Process The gravure applicator wheel is the most important individual component on an edge — bander. Adhesive transfer to the substrate takes place when the substrate comes into contact with the gravure wheel applicator, which should rotate at the same speed as the moving track. Fresh adhesive is resupplied to the applicator wheel […]

Edge veneering and edge banding constitute by far the main area employing hot-melt adhesives which are based predominantly on EVA copolymer resins. For some applica­tions, however, formulated polyamide hot melts are also used, particularly where excep­tional heat resistance of the bond is required. Modern materials such as decorative surface board products, used in the manufacture […]