Surface acidity pigments

The crystal structure of the OCP from Arthrospira maxima has been solved to 2.1 A resolution (Kerfeld et al. 2003). It is composed of two domains and the carotenoid, 3 -hydroxyechinenone, spans both. The carotenoid is almost completely buried within the protein only 3.4% of the pigment surface is accessible to solvent (see Figure 1.3a). The OCP is a dimer in solution the intermolecular interactions are largely mediated by hydrogen bonding among the N-terminal 30 amino acids, as shown in Figure 1.3b... 

Adsorption of e.g. rosin (abietic acid) at the pigment surface may - depending on the concentration of the rosin - reduce or accelerate the crystal growth. The presence of an excess amount of rosin during the production of diarylide yellow pigments of the Pigment Yellow 13 type affords an additional crystal modification, which can be identified by X-ray diffraction spectroscopy [4],... 

In general iron oxides are found to be predominantly acidic, but certain alloys may actually be mainly basic, as shown in the table for pigment 3. The performance of these pigments in dispersions correlated very well with the degree of surface acidity... 

A significant cation effect (with potentials in KCl higher than those in NaCI) in the acidic range is reported in [521], Unusual effects of the nature of 1-1 electrolytes on the electrokinetic behavior of a titania pigment (surface-modified with silica, alumina, and organic groups) are reported in [516]. 

The LSV dependence on surface acid concentration observed with most associative thickeners in this pigmented 20-latex study is illustrated in Figure 17. A latex-associative thickener network model for viscosities at low shear rates is proposed in Figure 18. This model is not the poly(acrylic acid)-poly(oxyethylene) complex observed over 2 decades ago (36). The coatings discussed are alkaline (pH 9). Examination of the data presented in... 

Figure 15. Low-shear-rate 2 s ) viscosity Pa s) dependence on the concentration of thickener, HEC ofM 700,000, in the aqueous phase of 0.32 volume fraction dispersions containing TiO% at a pigment to pigment plus latex volume ratio of 0.21. Key to latices open, 220, MMA-MAA (96 04) latex containing 0.00741 meqlm surface acid horizontal cross, 220, MMA-MAA (97 03) latex containing 0.00222 meqlm surface acid and vertical cross, 220, MMA-MAA (98 02) latex containing 0.00182 meqfm surface acid.

Synonyms Methyl bis (2-hydroxyethyl) cocoalkyl quaternary ammonium nitrates PEG-2 cocomethyl ammonium nitrate Quaternary ammonium compds., cocoalkylbis (hydroxyethyl) methyl, nitrates Uses Surfactant for cosmetics, agric., textiles, protective coatings, inks, pigment dispersions, acid pickling baths, metalworking, electroplating, plastics Trade Name Synonyms Arquad C/12 Nitrate t[Akzo Nobel Surf. Chem. AB http //www.surface.aiaonobei.com]... 

Seediness sed-e-nos n. (1) Particles in a coating caused by reactive pigments and acid components of the vehicle. (2) Defect in a clear varnish or lacquer caused by small particles sometimes visible when examined by transmitted light. On application, varnished or lacquered surfaces may present a bitty, specky or sandy appearance due to this defect. 

Wash primer Priming paint usually supplied as one- or two-component systems. The paint contains carefully balanced proportions of an inhibiting chromate pigment, phosphoric acid, and a synthetic resin binder mixed in an alcohol solvent. On clean, light alloy or ferrous surfaces, and on many non-ferrous surfaces, such paints give excellent adhesion, partly due to chemical... 

Prof. Fowkes s flow calorimetric work led to important advances in the understanding of the interactions between mineral fillers, polymers, and polymer additives. The work of S. T. Joslin and F. M. Fowkes [29] in which they time-sliced the outputs from an FMC and its accompanying DSD enabled them to determine differential molar heats of adsorption as a function of progress in the adsorption process, and gave an indication of the heterogeneity of strength of the acid or base adsorption sites on the filler or pigment surfaces. 

Today s requirements for dispersibility and dispersion stability of pigment-based ink jet inks require an extremely high level of performance. Dainippon Ink and Chemicals has developed new micro-encapsulation technologies for the solution of such problems. Their micro-encapsulated pigjnents exhibit concentrated polymer layers on the pigment surfaces. The encapsulation polymers used are basically (methjacryhc acid-(meth)acrylate ester copolymers. 

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