Paint coating system binders

Since the 1970s a trend to use water-based coating systems and glues instead of solvent-based products has been apparent. Most water-based paints and lacquers use polyurethane or acrylate as binders. For technical reasons the systems still contain organic cosolvents as well as pigments, biocides and surfactants (Hansen et al., 1987). 

Organic coatings are used to block the penetration of carbon dioxide or chloride ions. They form a continuous polymeric film on the surface of the concrete, of a thickness ranging from 100 to 300 pm. The binder can already be present in the liquid paint as a polymer, or the polymer can be formed due to chemical reactions between monomeric components that are mixed just before application. Modem coating systems are usually built up of several layers applied consecutively. They are compatible with the alkalinity of the concrete and are based on various types of polymers (e. g. acrylate, polyurethane, epoxy), pigments and additives, and are made suitable for application by the addition of solvents or diluents. 

Chemically blocking one of the polyaddition binder components (e.g., the polyisocyanate) gives a coating system stable at room temperature. Heat is required to deblock the component and enable cross-linking to occur. Stoving paints of this type are used in industry and in powder coatings. 

The expression water glass paints is understood to mean coating systems based on the binder water glass (potassium, sodium, or occasionally, lithium water glass). The general expression silicate coatings has been adopted for these systems and is therefore used throughout Section 2.15.1. 

SILIKOFTAL ED binder, optical fiber coatings Actllane 230HD30 binder, org. solvent systems Ethyl hydroxyethyl ceUilose binder, outdoor paints Potassium silicate binder, oven anticorrosive paints SILIKOPHEN P 60/D SiLiKOPHEN P 65/W SiLiKOPHEN P 70/MPA SILIKOPHEN P 80/20 SILIKOPHEN ... 

Historic developments in the paint industry resulted in experience of which solvent(s) were the best to use in certain paint systems. A review of these solvent types is given in Table 3.1 in conjunction with convertible and in Table 3.2 in conjunction with non-convertible surface coating systems commonly used by present industry. The following examples provide details of the various binder types [1]. 

Whilst there are some thermoset acrylic emulsions cormnerdally available, the bulk of the thermoset resins, used as the main binder system, are produced in solution. Some may then be made waterborne by neutralisation and inversion (dispersion) into a water phase. Lower molecular weights favour this qrproach. The rate of conversion from solvent based to waterborne industrial thermoset coating systems has been, and is, much slower than the conversion from architectural alkyd paints to emulsion altonatives. There are two principle reasons for this. Firstly there are problems of application and substrate wetting of many waterborne systems. Secondly, the modifications frequently required to induce water dispersibility reduce one or more of the essential performance properties required from the cured film, compared to a solvent based system. Water resistance, with many films having an increased tendency for blushing is one example. However, for some applications, such as electrodeposition, only waterborne systems will work. 

Uses Pigment wetting, binder, film-former, and modifier in paints, coatings, primers, lacquers and enamels for automotive, wood, plastic, paper, consumer electronics and leather applications, in graphic arts, inks and overprint varnishes film-former, gloss aid in nail care controlled drug delivery system in phannaceuticals Eastman DB [Eastman]... 

In the manufacture of coating materials, paints, varnishes, lacquers, dyestuff pigments, binding materials, and binders, surfactants are of great importance. Most of the systems used in these fields are dispersed. Therefore surfactants can accelerate the preparations of dispersions and improve their stability. For rewetting processes, like the so-called flush process, besides other anionic surfactants sulfosuccinates are also used. 

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