Surface tackiness

Print table adhesive remover. Used to remove print table adhesives or renew adhesive surface tackiness. Minimal odor development in use. 

The process of vulcanization was discovered independently by Goodyear (in 1839) in the U.S. and Hancock (in 1843) in the U.K. Both found that when natural rubber was heated with sulfur, the undesirable properties of surface tackiness and creep under stress could be eliminated. The chemical reaction involves the formation of interchain links, composed of two, three, or four sulfur atoms, between sites of unsaturation on adjacent chains. It has been foimd that about three parts sulfur per hundred parts rubber produces a useful elastomer, capable of reversible extensions of up to 700%. Increasing the sulfur, up to 30 parts per hundred, alters the material drastically and produces a hard, highly cross-linked substance called ebonite. The actual mechanism of the cross-linking reaction is still unclear, but it is thought to proceed via an ionic route. 

Vulcanization—A chemical reaction in which the physical properties of a rubber are changed in the direction of decreased plastic flow, less surface tackiness, and increased tensile strength by reacting it with sulfur or other suitable agents. The crosslinking of an adhesive material by means of heat or catalysis the chemical reaction of rubber with sulfur or other agents to alter its physical properties, e.g., to cause less tackiness, reduced plastic flow, and increased tensile strength. 

Slip n. (1) Film of coating is said to have slip when it has negligible surface tackiness, and appears to be lubricated. In actual fact, lubricants which are incompatible with the non-volatile constituents of finishes are frequently added in order that they may be exuded to the surface and confer slip. Nongreasing gold and silver baking varnishes are typical products to which lubricants are... 

However, there are concerns that N-vinyl lactams, such as N-vinyl caprolactam, may generate surface tackiness of the cured ink images or cause leaching (7). This arises since N-vinyl caprolactam does not readily copolymerize with acrylate monomers that are used in the composition (8). 

When the curing reaction is performed in a state in which the drying process is insufficient, a residual solvent or residual moisture is foamed by the heat release during pol5merization or is extruded from a cured material, bled out and left on the surface of the cured film, thereby causing a surface tackiness. 

Brief exposure to chemical media may cause surface tackiness, or, in severe cases, the chemical may truly dissolve the molecules in the case of thermoplastics... 

The changes in physical properties include decreased plastic flow, reduced surface tackiness, increased elasticity, much greater tensile strength, and considerably less solubility. More recently, certain thermoplastics (e.g., polyethylene) have been formulated to be vulcanizable. 

The other consideration in designing extended drying cycles is to understand the implication of temperature and time on the rubber formulation for characteristics other than moisture content. For instance, does surface tackiness of the closures increase or does coring of the closure change because of additional heat input ... 

Tensile strength Elastic modulus Melt viscosity Heat resistance Solvent resistance Elongation at break Surface tackiness Electrical properties... 

A thin, pure resin and sometimes pigmented finish, applied as a final operation to the reverse face only of a hand-laminated or spray-deposited thermoset composites moulding. The purpose is to seal, or offer further moisture and other protection to that irregular, fibre-textured surface, it prevents the reinforcement at the surface layer from becoming exposed during the components in-service life. To ensure that there is no residual surface tackiness, flowcoats often contain a small percentage of paraffin wax. 

The rise in adhesive force on painted surfaces (Fig. III.22) is clearly explained by the development of surface tackiness, which increases with temperature. 

The presence of an oil film on the surface causes adhesion as a result of surface tackiness. In this case the adhesive forces of the particles depend on the rheological properties and thickness of the oil film. 

Oiliness makes the surfaces tacky and increases the adhesion of particles (see 14). 

For a flow velocity exceeding a certain value (first critical velocity) the particles will rebound. The value of the first critical velocity depends on the elastic properties of the particle and obstacle surfaces and is inversely proportional to the particle size [see formula (V.ll)l. The coefficient of deposition increases when the possibility of particle rebound is eliminated. This may be achieved by making the surface tacky or increasing the adhesive force, particularly by virtue of the triboeffect and the cooling of the molten zone of contact. 

Surface-tacky hot-melt adhesives are marketed in containers or in the form of blocks or cubes in readily removable packs (silicone-coated paper) [33] or in meltable polyethylene bags. 

Pressure-sensitive hot-melt adhesives are surface-tacky and can be used by the application of pressure alone. These adhesives have infinite open times and are used at room temperature. Typically, pressure-sensitive hot-melt adhesives are supplied in form of blocks or cubes in silicone coated packaging units or preferably in polyethylene bags, which after melting form part of the adhesive. 

Ferric Chloride, saturated solution 1 week Surface tacky... 

Some processing aids can either improve or eliminate the surface tackiness of uncured compounds. Tackifying resins, especially phenolic types, are excellent for increasing surface tack, while materials such as primary amides can be used to reduce or eliminate surface tack. The primary amides may not be desirable for use in compounds meant for compression molded products because the resultant surface bloom on the preforms may cause knitting problems during the molding operation. 

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