Print elevated temperatures

Polymerization. Thermal polymerization or curing of an ink film at elevated temperatures can foUow many different chemical paths. Condensation and cross-linking reactions may be accompHshed with or without the use of catalysts. However, this method of drying generally has not been widely used for printing inks, except those used for metal and glass decoration, and some clear coatings. 

Because the heat distortion temperature of cured epoxy resins (qv) increases with the functionality of the curing agents, pyromellitic dianhydride is used to cross-link epoxy resins for elevated temperature service. The dianhydride may be added as a dispersion of micropulverized powder in liquid epoxy resin or as a glycol adduct (158). Such epoxies may be used as an insulating layer in printed circuit boards to improve heat resistance (159). Other uses include inhibition of corrosion (160,161), hot melt traffic paints (162), azo pigments (163), adhesives (164), and photoresist compounds (165). 

Ultem polyetherknides have appHcations in areas where high strength, dimensional stabiUty, creep resistance, and chemical stabiUty at elevated temperatures are important. Uses include electrical coimectors, wave guides and printed ckcuit boards for electronic equipment, food appHcations (microwaveable containers, utensils, and films), akcraft interior materials, and stetilizable medical equipment. 

This package contains Supplement 1 of API Recommended Practice 941, Steels for Hydrogen Service at Elevated Temperatures and Pressures in Petroleum Refineries and Petrochemical Plants, Fifth Edition. This package consists of the pages that have changed since the January 1997 printing and incorporates the changes in the October 1997 Errata. 

Flushing involves kneading the aqueous pigment presscake with varnish until a complete exchange has taken place between the two liquid phases. The aqueous phase is then separated and residual water removed by vacuum distillation at elevated temperature. Flushing affords a product which can be incorporated directly into a printing ink (Sec. 1.6.5.8). 

P.R.81 is used especially in three and four color printing and lends itself to various printing processes, therefore pigments of this type are referred to as Process Red in the USA. Used as a colorant for NC-based printing inks, SM types of P.R.81 may present problems as they are dispersed with steel balls or stored in steel containers as well as at elevated temperature. Catalytic decomposition of the binder and damage to the pigment may induce a color shift and increase the viscosity. 

PEN is a good candidate for labels where temperature tolerance is required, such as multi-layer labels for automobile bodies when being painted and dried at high temperatures. PEN is ideally suited for bar code labels where dimensional stability and registration are required at elevated temperatures. PEN labels have dimensional-excellence performance on printed circuit boards, in solvent- and aqueous-based painting operations, and in under-the-hood applications. PEN labels also provide substantially improved performance over PET or vinyl labels when the label must survive in harsh chemical environments. PEN performs extremely well in applications where the label must be in contact with organic solvents, such as acetone, ethers, toluene and phenol, as well as strong bases (30 % NaOH) and moderate acids. 

Lindsay, W. T., Jr. Liu, C. T. "Vapor Pressure Lowering of Aqueous Solutions at Elevated Temperatures" Office of Saline Water, U.S. Government Printing Office,... 

The target consists of a printed circuit board with two circuits. One circuit is exposed. The second circuit is protected and is used to compensate for the effect of elevated temperature on the electrical resistance of the circuit. The target is removed from the chamber 1 h after the start of a test and the reduction of the electrical resistance of the exposed circuit is measured. The target is then exposed to an atmosphere of 23°C and relative humidity of 75% for 24 h. The electrical resistance is measured again after the 24 h post-test exposure. The electrical resistance measurements are converted to the equivalent reductions in metal thickness, C, and C2 respectively, expressed in nanometers. 

B. The extractable pH of many well-washed photographic prints has been in ihe range of 5.5 to 6.0 (only a medium permanence level by ASTM Specification D-3290-74), but well-washed photographic prints have endured for many years. Estimates of paper permanence based upon rates of change at several elevated temperatures assess the overall effect of degradative reactions and resistance to those reactions, including the effects of acidity. 

For migration testing of printed materials intended for use at elevated temperatures only Tenax is used as food simulant. Testing should take into account possible degradation products formed at elevated temperatures. Prior to testing, the sample should be preheated in a closed container. 

Critical requirements for PE are rapid processing, thinner yet stronger films, ease of direct printing or adherence of labels, rapid heat sealing, high strain rate at high strain for stretch wrap, plastic memory for shrink wrap, cross-linkability to resist creep and stress relaxation, cross-linking to resist elevated temperatures when the... 

The first use of ink-jet printing to construct MEMS has recently been described by Fuller et al. [64]. Metal nanoparticles suspended in a solvent were deposited, followed by sintering at elevated temperatures. 

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