Solution dip coating

As with aqueous solutions, dip coatings can be obtained when more electronegative metals are placed in ionic liquids containing more electropositive metal ions e.g. silver ions will be deposited onto copper metal. Unlike aqueous solutions,... 

Typicai processing methods - calendering, compounding in solution, dip coating, extrusion, molding (compression, injection), sheeting, vulcanization ... 

Electrodes coated with both CoPP and CoPc films have been prepared mainly by two methods adsorption at the electrode surface from a solution (dip coating) [27] or by repetitive cyclic voltammetry [28]. Canevari et al. [29]. prepared a CoPc carbon-paste electrode where the CoPc was synthesized in situ on a SiOa/SnOa mixed oxide obtained by the sol-gel method. ... 

Tire Cord. Melamine resins are also used to improve the adhesion of mbber to reinforcing cord in tires. Textile cord is normally coated with a latex dip solution composed of a vinylpyridine—styrene—butadiene latex mbber containing resorcinol—formaldehyde resin.. The dip coat is cured prior to use. The dip coat improves the adhesion of the textile cord to mbber. Further improvement in adhesion is provided by adding resorcinol and hexa(methoxymethyl) melamine [3089-11 -0] (HMMM) to the mbber compound which is in contact with the textile cord. The HMMM resin and resorcinol cross-link during mbber vulcanization and cure to form an interpenetrating polymer within the mbber matrix which strengthens or reinforces the mbber and increases adhesion to the textile cord. Brass-coated steel cord is also widely used in tires for reinforcement. Steel belts and bead wire are common apphcations. Again, HMMM resins and resorcinol [108-46-3] are used in the mbber compound which is in contact with the steel cord to reinforce the mbber and increase the adhesion of the mbber to the steel cord. This use of melamine resins is described in the patent Hterature (49). 

Solution Deposition of Thin Films. Chemical methods of preparation may also be used for the fabrication of ceramic thin films (qv). MetaHo-organic precursors, notably metal alkoxides (see Alkoxides, metal) and metal carboxylates, are most frequently used for film preparation by sol-gel or metallo-organic decomposition (MOD) solution deposition processes (see Sol-GEL technology). These methods involve dissolution of the precursors in a mutual solvent control of solution characteristics such as viscosity and concentration, film deposition by spin-casting or dip-coating, and heat treatment to remove volatile organic species and induce crystaHhation of the as-deposited amorphous film into the desired stmcture. 

Dip and Spin Coating. The dip coating technique described for webs can also be used to coat discrete surfaces such as toys and automotive parts. The surface to be coated is suspended on a conveyor and the part dipped into the coating solution. The surface is then removed, the coating drains, then levels to give the desired coverage. The object is then dried or cured in an oven. 

We prepared ceria on Ni substrate by sol-gel coating method. Ceria sol solution was prepared with ceria sol solution (Alfa, 20% in H2O, colloidal dispersion) mixed with ethanol (99.9%, Hayman) with weight ratio (1 2) and stirred. Ceria was deposited on Ni substrate by dip coating method. The variation number of dipping was carried out to obtain different coating ratio. The anode was completely dipped into the ceria sol solution for several seconds and dried at a temperature of 50 C for 24 hours in air atmosphere followed by calcination at 700 C for 30 minutes in 5%H2-N2 atmosphere. 

Asymmetrical membrane capsules were prepared, for example, by dip coating mandrels with solutions containing 15 wt% CA and 33 wt% ethanol in acetone. After the mandrels were withdrawn from the coating solution they were immersed in water to precipitate the polymer and create the asymmetrical membrane capsule shell. This process was used to create both the body and the cap for the capsules. The capsules were sealed at the juncture between the cap and body by banding with a solution of CA in acetone. 

After the precursor stock solution is prepared, various techniques can be used to coat the substrate, depending on the solution viscosity, required film thickness and coverage. The most common methods in the semiconductor industry are spin- and dip-coating. Other processes that are used for deposition include spray coating and stamping. A summary of the uses, limitations, and advantages of the various thin film deposition methods is reported in Table 2.2. 

In the dip coating, a substrate is immersed in a liquid solution and then withdrawn with a well-defined extraction speed under controlled temperature and atmospheric conditions. There are five essential steps involved in this process immersion, extraction, wet layer formation, drainage, and solvent evaporation, as illustrated in Fig. 3.9. 

The use of the dip-coating technique allows to obtain different overlay thicknesses by acting on the solution viscosity and extraction speed as stated by the Landau-Levich equation (see (3.14)). In particular, thicker overlays can be obtained by increasing the extraction speed and/or by increasing the solution viscosity. 

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