Vehicles systems

Dispersibility. The dispersibiHty of a pigment is measured by the effort required to develop the fuU tinctorial potential of a pigment in a vehicle system. DispersibiHty differs from system to system depending on pigment—medium interaction and compatibiHty. 

Concentrates are made in the same manner as dispersions but often with less work placed into the colorant—vehicle system, thus higher yields and rates are obtained and a lower cost product is made. Usually, the concentrate goes through an additional processing step with the resin in which additional energy is provided to the system, thus ensuring more dispersion. 

Besides the solvent composition, the vehicle system is responsible for various drying deficiencies associated with water-borne coatings, such as slow initial dry time, loss of dry, poor through drying, and hardness (see Coatings). 

The vehicle system of water-borne coatings can be divided into two categories water-emulsifiable vehicles and water-soluble vehicles. 

Kato, Y., K. Ando, and Y. Yoshizawa, 2003. Study on a regenerative fuel reformer for a zero-emission vehicle system, J. Chem. Eng. Japan, 36 (7), 860-866. 

Standards Development General FC Vehicle Safety SAE Fuel Cell Vehicle Systems SAE Fuel System Components CSA Containers SAE Reformers SAE Emissions SAE Recycling SAE Service/Repair SAE... 

National template for hydrogen vehicle systems and refueling facilities. 

NASA is focusing on liquid-hydrogen power as part of its Vehicle Systems program. This includes a zero-emissions hydrogen-powered fuel-cell aircraft with cryogenic electric motors in the wing. 

The particle size distribution of an organic pigment powder is usually different from that found in the pigment-vehicle system and since both have practical importance, methods were developed for their determination. 

A number of potential users, such as the printing industry, are interested in the solvent fastness not only of a pigment but of an entire pigment-vehicle system. Standardized tests are available. A proof print of a certain size is placed inside a test tube and allowed to remain in the target solvent at 20°C for 5 minutes. The change in solvent color is determined and the print dried and compared with an untreated specimen. Standard solvents [14] are ethanol or the following mixture ... 

This limit, which might be referred to as the ultimate tinctorial strength , reflects the maximum degree of dispersion which can be achieved in a particular vehicle system under a certain set of conditions. However, experimental results may deviate more or less from the theoretical concepts and an ideal dispersion is not normally realized not all agglomerates are broken down entirely. This, however, is of no consequence, because even the experimentally determined ultimate tinctorial strength is by no means considered a standard for industrial application technical operations are not always allowed to go to completion, and the dispersion process is often discontinued, mainly for economical reasons. 

The dispersibility of a pigment in a particular vehicle system is also reflected by the viscosity of the pigmented medium and by the gloss that it produces in application. Viscosity and gloss are frequently considered more suitable parameters to indicate the state of dispersion of a pigment in an application medium than the tinctorial strength, which reaches its optimum at a point at which other parameters, such as gloss, can be improved. 

The lightfastness of a material is defined by the inherent ability of a given pigment-vehicle system to retain its initial color value upon exposure to daylight. It is thus a system-related parameter which cannot be determined in connection with pure pigment only. 

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