Emulsion vehicle

Emulsion vehicles are prepared by emulsion polymerization in water in the presence of surfactant stabilizers. Viscosity is not dependent on molecular weight but only on solids content and particle size distribution. As a result, high molecular weights ( 200 000 g moT ) are achievable at low viscosity. Emulsions with small par- 

Most printing ink emulsions are resin supported . Printing ink emulsion polymers contain a support resin to reduce MFFT (minimum film forming temperature), and insure film coalescence. A support resin also decreases the need for surfactants. A support resin provides ink re-wettability, improves compatibility with pigment dispersions, and improves ink transfer and printability. Support resins are typically styrene acrylic polymers with acid functionality that are amine neutrahzed. 

Polyurethanes are known to give excellent chemical and product resistance properties but increase cost. A water soluble polyurethane is made by adding acid modified monomer to the polymer backbone, the polymer is neutralized with amine, then used as a support resin in ink grade styrene acrylic emulsions. Polyurethane supported styrene acrylic emulsion polymers may be used to balance the high cost of polyurethanes and provide improved chemical resistance [8]. 

Emulsion polymers are supplied in bulk quantities at sohds levels between 45 and 60 %. They are produced by emulsion polymer manufacturers such as SC Johnson Polymer, Rohm Haas, Avecia, Air Products, Westvaco, B.F. Goodrich and others. 

Outlined in Tab. 5-4 are applications, emulsion characteristics, and physical properties of the styrene acrylic emulsion vehicles used in flexo and gravure ink. An emulsion vehicle comprises 25 to 35 % of the total ink formula. The table is sorted by 

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Naveh, N., S. Muchtar, and S. Benita. 1994. Pilocarpine incorporated into a submicron emulsion vehicle causes an unexpectedly prolonged ocular hypotensive effect in rabbits. J Ocul Pharmacol 10 509. 

The concept of using anionic nanosized emulsion vehicles for enhanced percutaneous absorption of nonsteroidal anti-inflammatory drugs (NSAIDs) and diazepam was clearly proven [189, 190], NSAIDs and diazepam in a nanosized emulsion vehicle also demonstrated noticeable systemic activity. The o/w emulsion was tested for primary irritation in humans in a 48-h trial. Low irritancy and excellent human acceptance were observed, subsequently making the further development of a nanosized emulsion vehicle very attractive. 

Klang, S. H, Frucht-Pery, J., Hoffman, A., and Benita, S. (1994), Physicochemical characterization and acute toxicity evaluation of a positively-charged submicron emulsion vehicle, J. Pharm. Pharmacol, 46, 986-993. 

Friedman, D. I., Schwarz, J. S., and Weisspapir, M. (1995), Submicron emulsion vehicle for enhanced transdermal delivery of steroidal and nonsteroidal antiinflammatory drugs,/. Pharm. Sci., 84, 324-329. 

See paint emulsion vehicle protective coating antifouling paint. 

Each gram of lotion contains 10 mg clotrimazole USP dispersed in an emulsion vehicle composed of benzyl alcohol NF (1%), cetearyl alcohol 70/30 (3.7%), cetyl esters wax NF, octyldodecanol NF, polysorbate 60 NF, sodium... 

Figure 8.3 Permeation profile for dimethyinitrosamine (DMN) across human skin in vitro. DMN was applied at finite dose levels in an oil-in-water emulsion vehicle. Note that permeation was significantly reduced by evaporation following 6 h of exposure. (From Brain, K.R., Walters, K.A., James, V.J., Dressier, W.E., Howes, D., Kelling, C.K., Moloney, S.J., and Gettings, S.D., Food Chem. Toxicol., 33, 315-322, 1995. Used with permission.)...

Typically, emulsion formulations reported in the literature are negatively charged. They are based on lecithin combined with nonionic or anionic emulsili-ers. The approach to design an emulsion vehicle bearing a positive instead of a... 

R. I. Jepps.son, Parenteral administration of lipid-soluble drugs in oil emulsion vehicles. Acia Pharm. Suecica Suppl., 13 43, 1976. 

Uses in the manufacturing of acrylic resins for use in paint formulations, industrial coatings and latexes in the manufacturing of plastics, such as ethylene ethyl acrylate in the manufacturing of poly-acrylate elastomers and acrylic rubber in the forming of denture materials water-emulsion vehicle for paints, textiles and paper coatings, leather finishes, resins and adhesives lends flexibility to hard films A... 

This observation did promote great interest. Two big competitive systems at that time were essentially, vinylated oleoresinous materials, like styrenated al-kyds and oils, and the emerging, emulsion vehicles like SBR latices. 

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