Лако-красочные материалы — производство

A. Veneer Splicing Particleboard with a decorative wooden veneer surface usually employs a hot-melt adhe­sive to effectively mate veneer edges down the length of the joint. Polyamide hot-melt adhesives are widely used for this veneer splicing process. The adhesive is more often than not supplied as a thread and positioned as such in a zigzag […]

In general, one should ensure that operation of the machine is in accordance with the manufacturer’s instructions, being sure to set the machine according to the adhesive supplier’s specifications for line speed, operating temperature, and adhesive coating weight. During application, the following guidelines should be observed: 1. Adhesive reservoir temperature: 204° C 2. Application roller […]

The polyamide hot melts are high-performance systems and are used selectively where good heat resistance is required. Their high cost relative to EVA types makes them rather unattractive for general use. Polyamide resins offer high tensile strengths and high initial tack, often without the need for additional formulating. Their higher melt points ensure good heat-resistance […]

Because of their relatively high melt viscosities, the EVA hot melts need special manufac­turing equipment. For example, a Z-blade mixer such as a Baker Perkins or Winkworth with oil-heated jacketing is required. Mix temperatures are kept as low as possible (± 110° C) to keep bulk thick. The high-viscosity kneading action ensures rapid dissolution of […]

EVA hot melts consist basically of the following: 1. EVA copolymer 2. Tackifying and adhesion-promoting resins (e. g., hydrocarbon, rosin esters, coumarone-indene, terpene resins) 3. Fillers, usually barium sulfate (barytes) or calcium carbonate (whiting) 4. Antioxidants 1. EVA Copolymer EVA copolymer is the main binder in the system and largely influences the following: (a) viscosity […]

A. Physical Characteristics Edge veneering requires use of a hot-melt adhesive that is relatively high in viscosity at application temperatures (usually around 200°C). The reasons for this are as follows: 1. The adhesive must have sufficient body to prevent flowing from vertical surfaces after application. 2. It must not penetrate the substrate surface too deeply, […]

A. Pizzi Ecole Nationale Superieure des Technologies et Industries du Bois, Universite de Nancy I, Epinal, France I. INTRODUCTION Hot melts are a widely used class of adhesives that are used for many applications but are rarely used for structural bonding, as seldom are they able to match the tensile strengths of other adhesive classes. […]

One of the main uses of polyester resin is to function as the adhesive for glass-fiber lamination. The cross-linking reaction of unsaturated polyesters is exothermic; that is, it is accompanied by a rise in temperature. Indeed, one of the useful features of an inorganic adherend functioning also as a reinforcing agent in these resins is […]

For a given polyester formulation, the properties of the final compound are a function of its condensation (e. g., carboxyl and hydroxyl group concentration), viscosity and mole­cular weight distribution, and the structural features of the three-dimensional network obtained after free-radical copolymerization. An increase in the molecular weight of an unsaturated polyester improves its hardness, tensile […]

The free radicals first react with the chemical inhibitor which has previously been added to the resin, since the inhibitor material must be chemically dissipated before any reaction between free radicals and the ^=C double bonds can proceed [5]. Apparently, the free radicals serve to open the double bonds in the polyester linear chain to […]