Thermal transfer

Thermal reforming Thermal sensitization Thermal stability Thermal transfer Thermal-transfer printing Thermal treatment Thermal wave imaging Thermate Thermate-TH2 Thermate-TH3 Therm-Chek... 

In conventional tenter orientation, the sequence of steps is as described above (MD—TD). In some cases it is advantageous to reverse the draw order (TD—MD) or to use multiple draw steps, eg, MD—TD—MD. These other techniques are used to produce "tensilized" films, where the MD tensile properties are enhanced by further stretching. The films are generally unbalanced in properties and in extreme cases may be fibrillated to give fiber-like elements for special textile appHcations. Tensilized poly(ethylene terephthalate) is a common substrate for audio and video magnetic tape and thermal transfer tape. 

PWRs operate differendy from BWRs. In PWRs, no boiling takes place in the primary heat-transfer loop. Instead, only heating of highly pressurized water occurs. In a separate heat-exchanger vessel, heat is transferred from the pressurized water circuit to a secondary water circuit that operates at a lower pressure and therefore enables boiling. Because of thermal transfer limitations, ultimate steam conditions in PWR power plants ate similar to those in BWR plants. For this reason, materials used in nuclear plant steam turbines and piping must be more resistant to erosion and thermal stresses than those used in conventional units. 

Thermal transfer printers are relatively complex, both mechanically and electronically. In addition to precise mechanisms they require sophisticated electronics for networking and PostScript interpretation. Cost of equipment and consumables ( 0.50— 1.00 per page) is relatively high. 

Dye sublimation requires more heat dissipation and a longer (>10 ms) heating period to make a dark mark than does thermal transfer. Carehil manipulation of heating time and temperature can proportion mark size and dye content to cover a wide density range (0 to ca 2 optical density). 

In order to develop the dyes for these fields, characteristics of known dyes have been re-examined, and some anthraquinone dyes have been found usable. One example of use is in thermal-transfer recording where the sublimation properties of disperse dyes are appHed. Anthraquinone compounds have also been found to be usehil dichroic dyes for guest-host Hquid crystal displays when the substituents are properly selected to have high order parameters. These dichroic dyes can be used for polarizer films of LCD systems as well. Anthraquinone derivatives that absorb in the near-infrared region have also been discovered, which may be appHcable in semiconductor laser recording. 

The need to obtain color hard copies from electronic systems such as TV and video sets, or from personal computers, has been increasing. Several methods have been proposed to obtain hard copies of full color images. Among them, sublimation thermal-transfer printing has the following characteristics the quaHty of the printed color picture is extremely high, and the equipment is compact, quiet, and easy to manipulate as well as to maintain. 

Table 8. Examples of Magenta Dyes for Sublimation Thermal-Transfer Printing...

It is seen that a very significant temperature increase occurs particularly at high pressures. It would appear that, due to the poor radial thermal transfer in the column, the thermostat had little effect on the temperature change. Katz et al. [15] concluded that increases in column temperature resulting from high inlet pressures could seriously affect the accuracy of retention measurements. The heat evolved on changing the flow rate from 4 to 18 ml/min., accompanied by a corresponding... 

Almost all dyes are quinones or azaquinones of compound 2. The majority are used for thermal transfer processes a recent example is compound 306 (98USP5792587). The second major class are azo dyes, prepared either from aromatic diazonium salts as in compound 307 (95GEP4319296) or from a triazolopyridine 3-diazonium salt as in 308 (81BRP2054630). 

Conduction is heat transfer through a solid nonporous barrier when a temperature difference exists across the barrier. The thermal transfer capability of the specific barrier or wall material, known as thermal conductivity, determines the temperature gradient that will exist through the material. 

Conductive Good thermal transfer Requires a secondary operation... 

If the deposit is allowed to thicken significantly, thermal transfer is reduced and, in extreme cases, steam pressure drops. 

Little evidence for thermal transfer of a 7T-ring in recoil studies has been published, and that only when no other ligand was present in the molecule. It is found 85, 37) that ferrocene is susceptible to thermal annealing in a ferrocene matrix, where the reaction clearly must be... 

In the parallel-plate method, the heat flux downward is measured hy a fluxmeter under which the thermal bond material and the molten salt of interest are located. Because the thermal transfer is only conductive if the thermal contacts are perfect, the balance of heat flow through the... 

A number of experiments and flnite-element simulations were done to confirm even flow distribution, uniform pressure drop and isobaric properties and also to analyse quantitatively mass and thermal transfer for the wide packed-bed reactor [78]. 

Thermal conductivity enhancement in solid reactor bed becomes one of important subjects. Enhancement of reactor bed thermal transfer using mixture of reactants and heat transfer enhancer were discussed in France... 

At milli-kelvin temperatures, the problem of contact resistance between helium and solids becomes more complex. Thermal transfer phenomena take place involving spins and thermal resistance of sintered materials. The understanding of the thermal transport at very low temperature is of the utmost importance, also from a technical point of view, since helium is the working substance in dilution refrigerators (see Chapter 6). 

I tjzoIo[ 1,5-/] [1,2,4] triazole azomethines were investigated and used for manufacturing of inks, optical filters, thermal transfer printing materials, and toners. Some of them were prepared and formulated into a water-thinned jet printing ink <2002JAP256164, 2000EUP1035172>. 

MB Wolk, PF Baude, JM Florczak, FB McCormick, and Y Hsu, Thermal Transfer Element for Forming Multilayer Devices, U.S. Patent 6,114,088, 2000. 

---