Coating Electrostatic

Baytron , a conducting polymer [154] derived from 3,4-ethylenedioxythiophene, is a commercially available product that can be used as an antistatic or electrostatic coating of plastics and glass. Moreover, it has successfully been applied as counterelectrode in capacitors and as a hole-injection layer in organic light-emitting diodes [155]. 

Upgrading towards use of a more-sophisticated plastic family use of more thermostable plastics that can withstand on-line electrostatic coating (e-coating). 

Considering the processing fundamentals of this dry process, almost all of the issues associated with the scale-up of more traditional film-coating processes are eliminated, and the key objective is to feed tablets directly from the tablet press into the electrostatic coating operation, and thence in to packaging. Thus, once the process is defined in terms of coating one tablet, it is replicated an appropriate number of times in order to coat all of the tablets in the batch. 

Electrostatic Coating None Identified None Identified... 

Because of the custom design associated with this class of coating, no electrostatic coating subclasses or examples have been identified. 

The organic cellulose ester plastics are versatile materials and can be processed by almost any hot-processing technique used for thermoplastics. The principal techniques for all three plastics are injection molding and extrusion. Blow molding is also possible. Butyrate and propionate powder are used in tluidized-bed and electrostatic coating processes, as well as in the rotational molding process. 

Electrostatic coating has been developed recently to allow for the deposition of thin polymeric films without the need for any solvent. Films are formed when a charged particle is attracted to a substrate of opposite charge.41 An example is the Accudep controlled release system.42... 

The powder can be applied directly to the substrate surface by electrostatic coating processes or dusting onto a warmed surface. It can also be formed into shapes or preforms by the application of pressure in a die mold. This process is similar to how pharmaceutical tablets are made. In this way shaped preforms can be made that will conform to a specific joint geometry. There are a wide variety of applications to which epoxy preforms can be adapted. They can be used to... 

The sol-gel reactions have mainly been investigated in alcoholic solution, which is a reaction medium easily allows electrostatic stabilization by propriate choice of the pH. This type of stabilization can only be used in a few cases as a means for incorporating the colloidal particle agglomerate-free into tailored matrices, since these matrices, as a rule, destroy the electrostatic "coating" around the particles. As a consequence, agglomeration takes place, and the high transparency required for optical application is lost For this reason, another type, the so-called short organic molecule stabilization by tailored surface modification for colloidal particles, has been developed, the principles of which in comparison to the electrostatic stabilization is schematically shown in Fig. 14. 

In dry coating processes the frit is ground dry with or without additives to the required fineness. For powder coating no further additives are necessary. Powders for electrostatic coating have to be hydrophobized to adjust the specific resistivity of the powder surface to lO to 10 Clem. This is achieved by adding charging agents to the mill. Special silicones are especially suitable therefor. 

Powders for electrostatic coating are brought to a. specific re.si.stivity of at lea.st 10 Q-cm by coating with silicone oils... 

In sheet steel enameling (particularly for flat-ware), the powder electrostatic coating has become the preferred process. The electric voltage difference between the pistol and the object is with 60 to 90 kV slightly weaker than that... 

The disk electrostatic system is perhaps the ultimate in electrostatic coating systems. It has a high application efficiency and great flexibility. It is being used to apply topcoat finishes to all types of household appliances, bicycle parts, toilet seats, and even golf balls. It represents the best means of getting the film-forming components of a liquid finish onto a surface so that they can be converted to a solid plastic film. 

Halar . [Ausimont] Ethylene chlorotri-fluoroeAylene copolymer, melt pro-cessable fluoropolymer for extrusion, itg. mtdding, blow molding, rotomold-ing, fluidized bed or electrostatic coating processes. 

RMB Products, Inc., has developed a tank that has been rotomolded ] around fins to improve heat transfer to and from the tank. The fins were first electrostatically coated with the resin powder before being placed in the rotational molding machine. The precoating of the fins was found to improve resin adhesion. The polymer of choice for this tank (Fig. 6.44) was PFA or ECTFE, which allows the tank to be used to store aggressive chemicals. 

A characteristic of electrostatic coating with both charging processes is that the charged powder will wrap around the back of the substrate, especially as the powder builds up on the front of the part being coated. This is usually referred to as electrostatic wrap. This can be both an advantage or a disadvantage. 

Ageflex FM-1Q80DMS EINECS 229-995-1 Ethan-aminium, N,N,N-trimethyl-2-((2-methyl-1-oxo-2-prop-enyl)oxy)-, methyl sulfate Ethanaminium, N,N,N-trimethyl-2-((2-methyl-1-oxo-2-propenyl)oxy)-, methyl sulfate (2-(Methacryloyloxy)ethyl)trimethylammonium methyl sulphate. Antistatic finish for polyester fibers, flocculant and coagulant for industrial process water treatment, flocculant for mineral recovery, ion exchange resins, adhesives, xid dye receptivity, electrostatic coatings on wood, retention aids for paper. Solid soluble in H2O, d = 1.183 cationic. Rit-Chem. 

As a result of the particulate nature of the binders only a low gloss and, in some cases, only limited corrosion protection can be obtained. Waterborne paints based on dispersions can be applied by spraying, however they are of only limited use for electrostatic coating and dipping applications due to their rapid drying properties. 

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