Solvent paper lamination

With up to six active hydrogen sites, melamine reacts with formaldehyde and methanol to form a large family of resins. A resin ratio of Z mol formaldehyde to 1 of melamine is used extensively to impregnate countertop surface paper laminates, making them flame and boil resistant. A resin ratio of 6 mol of formaldehyde to 1 of melamine followed by excess methanol forms a methylolated cross-linking resin used to impart heat and solvent resistance to numerous latex-based coatings. 

Laminates. While phenol-formaldehyde-kraft-paper laminates are used for counters, cahinets, walls, and panels in puhUc transportation, the dark hrown-hlack color requires a decorative overlay to make it attractive. Colored and printed paper is impregnated with melamine-formaldehyde resin and applied as the surface layer to these laminates, providing decoration along with resistance to scratches, heat, ultraviolet, water, solvents, and stains. The laminating resin is made with melamine/formaldehyde ratios of 1/2 to 3 and press-cured at 125 to 150°C. This uses 14 percent of the melamine-formaldehyde market. 

Paper laminates Degrease with solvent Abrade with fine-grit emery paper Repeat degreasing... 

The largest market for elastomer-based adhesives is that of lamination (see Laminates). Modem office furniture having Formica as a surfacing material is made with an elastomer-based adhesive. Tile adhesives for ceramic or carpet tile are also elastomer-based and usually solvent appHed. Paper adhesives and shoe manufacture also use substantial quantities of mbber-based materials. Solvent-weld adhesives are used to join plastic plumbing and to repair vinyl sheeting. 

Layered Structures. Whenever a barrier polymer lacks the necessary mechanical properties for an appHcation or the barrier would be adequate with only a small amount of the more expensive barrier polymer, a multilayer stmcture via coextmsion or lamination is appropriate. Whenever the barrier polymer is difficult to melt process or a particular traditional substrate such as paper or cellophane [9005-81-6] is necessary, a coating either from latex or a solvent is appropriate. A layered stmcture uses the barrier polymer most efficiently since permeation must occur through the barrier polymer and not around the barrier polymer. No short cuts are allowed for a permeant. The barrier properties of these stmctures are described by the permeance which is described in equation 16 where and L are the permeabiUties and thicknesses of the layers. 

Because of the lack of solubility in the usual solvents, aniline-formaldehyde laminates are made by a pre-mix method. In this process the aniline hydrochloride-formaldehyde product is run into a bath of paper pulp rather than of caustic soda. Soda is then added to precipitate the resin on to the paper fibres. The pulp is then passed through a paper-making machine to give a paper with a 50% resin content. 

Solvent-home urethanes are still widely used to bond leather and athletic shoes. The OEM automotive market uses some solvent-home urethanes together with chlorosulfonated polyethylene as a primer. Some urethane solvent-home packaging adhesives are used for cap liners and for paper and foil lamination. Some textile laminating applications are still based on solvent-home urethanes. 

Trace Solvent Removal. Several papers were written by Nadeau (4) and by Gilbert (5) and co-workers on gas chromatographic methods for determining solvent traces remaining in flexible packaging films after printing or adhesive lamination. With proper equipment and techniques,... 

When mentioned, deactivated silica gel means that it was treated with 5% triethy-lamine in pentane and the column was eluted with the same solvent mixture until the outflowing eluent was basic according to pH paper. 

Polychloroprene. Polychloroprene dispersions have a range of qualities similar to those of solvent-based polychloroprene adhesives and a similar range of uses. As an example, the bonding of vinyl materials with phenolic resin/paper decorative laminates often is carried out with these products. It is necessary to incorporate acid-acceptor dispersions of metallic oxides, and the dispersions in general do not provide such long open times as solvent-based polychloroprene adhesives. 

The phenol/furfural resins have a greater hydrocarbon solvent tolerance than phenol/formaldehyde resins. This is an advantage in the preparation of resin solutions used for the impregnation of paper or cloth for laminating. 

Use Ingredient of polishes, special lubricants, and coatings lubricants for metals and in textile and molding industries in wax polishes as dye solvent plasticizer for laminated fiber products rubber hydrochloride chlorinated rubber and cable lacquers carbon paper and inks emolhent in cosmetic and pharmaceutical products lipsticks damp proofer for concrete flavoring. 

Coated and laminated textiles usually consist of a textile substrate, which will typically be a woven, knitted or nonwoven fabric, combined with a thin, flexible fdm composed of a natural or synthetic polymeric substance. A coated fabric is one in which the textile substrate has a polymer film applied directly to one or both surfaces as a viscous liquid in a solvent or water, the thickness of which is controlled by application via a blade or similar aperture. A transfer coated fabric is an intermediate product in which a thermoplastic film is first prepared on a release paper prior to thermally bonding to the textile substrate. A laminated fabric usually consists of one or more textile substrates that are combined with a pre-prepared polymer film or membrane by adhesives or heat and pressure (Hall, 2000). 

Paper may also be solvent or aqueous coated, e.g. PVdC, emulsions, varnishes, lacquers, or laminated to plastics by adhesion or direct extrusion or to foils by adhesion, all to form laminates. These laminates containing paper are dealt with in Chapter 9. 

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