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Water‐borne coatings Increasing use of water‐borne emulsion coatings for original equipment manufacturers (OEM) and product finishes is requiring greater efficiency in coalescing‐aid solvents, an Eastman Chemical Co. representative said at a recent Chicago Society for Coatings Technology meeting. Eastman's Ronald K. Litton said emulsions designed for OEM and industrial applications have higher glass transition temperatures than emulsions used in architectural paints. That requires higher levels of coalescing aid to achieve good film formation. As a result, coalescing‐aid efficiency with a given emulsion system is a key factor, both from environmental (lower‐volatile organic compound (VOC)) and economic standpoints. Several properties should be examined when a coalescing aid is selected for water‐borne emulsion industrial coatings. The formulator should consider the evaporation rate and solubility parameter of the coalescing aid, along with its distribution pattern in a specific emulsion system. Those properties are important in defining the efficiency of a coalescing aid in terms of its ability to lower the minimum film‐forming temperature (MFFT) of an emulsion system. The coalescing aids also must be hydrolytically stable to provide minimum loss of efficiency due to ageing, Litton said. He showed several charts designed to assist formulators in the selection of optimum coalescing aids for emulsion systems. At the same conference, James T.K. Woo of The Glidden Co. discussed the grafting of high‐molecular‐weight epoxy resins with styrene‐methacrylic acid monomers, producing a water‐reducible copolymer. Grafting takes place at the aliphatic carbons of the epoxy resin, according to carbon‐13 NMR spectroscopy. The study was a follow‐up to a paper presented 14 years ago. Woo said recent research indicates that five grafting “peaks” were identified on a 400 megacycle carbon‐13 nuclear magnetic resonance spectroscopy instrument. The paper provided several theoretical calculation on grafting. Three of the graft peaks resulted from grafting at the secondary methylene carbons ‐CH2‐ and two resulted from grafting at the tertiary carbon ‐CH‐. The ratio of grafting at ‐CH2‐ to ‐CH‐appears to be 2.7:1 — lower than the 4:1 ratio of protons present on the aliphatic carbons that are susceptible to hydrogen abstraction leading to grafting. That indicates that the tertiary hydrogen is somwhat more susceptible to grafting than the methylene hydrogens, he said.

Scarcely a decade has passed since the paint industry embraced the concept of electrocoating in its modern sense. Its acceptance has been a gratifying one simply because it has been possible to translate this highly advanced scientific process into clearly demonstrated practical benefits. These benefits reflect themselves in the adaptation of the process to automation, and thus to economy in coating coupled with the achievement of highly desirable coating properties.

Ink transfer means for printing machine. In GB patent 2278574 David Edward McManamon describes an ink transfer means for a printing machine. It includes an application roller to receive ink from an ink rail and transfer ink to print rollers for printing. A pair of wiper rollers are provided above and below the centre of the application roller and in close proximity to the surface. The wiper rollers are driven in opposite directions so that they effectively wipe the surface of the application roller. This prevents build up of ink and the associated ink misting, irrespective of the direction of rotation of the application roller.

New facilities at Hoechst UK's northern headquarters of Holywell Green were officially opened by Donald Thompson MP on May 19, marking the completion of a major phase in a long‐term programme of reconstruction and redevelopment.

ASTM D01.56 on Printing Inks, a subcommittee of standards‐writing Committee D‐1 on Paint and Related Coatings and Materials, has announced the approval of five standard test methods for the evaluation of printing inks and prints.

Paints (surface coatings), primarily used to protect various substrates from the corroding action of acidic and alkaline substances, largely contain polymers as coating formulations. Examples of generally used polymers are: butadiene based (space), epoxy resins and silicone fluids (concrete vinyl polymers and polyurethanes (optical fibres) alkyds and acrylics (electronics) and polyester resins (wood, metal and fibre‐glass reinforcements). The binder‐pigment interaction controls important properties like hardness, flexibility, permeability, adhesion, gloss, and mechanical properties and contributes finally to the success or otherwise of the paint as a protective surface‐coating. Excellence of pigment dispersion and paint performance are thus intimately related.

ABM Chemicals Ltd is exhibiting its range of photosensitisers for uv curing including the Glocure benzoin ethers. These highly cost effective materials ensure maximum utilisation of uv energy for the polymerisation process.

A mixed metal oxide-based spinel ceramic pigment has been successfully synthesized incorporating inorganic, high-temperature stable furnace cement as an inbuilt binder. Step by step synthesis was done for the spinel and cement mix formulations.

The pigment mix was synthesized by a solid-solid method where the inorganic binder was incorporated in the mix. The results suggested that CoCuMn-based spinel ceramic pigment with cement mix could be obtained at an annealing temperature of 1,100ºC for 1 h and the size, morphology and crystallinity of spinel mix were greatly influenced by the calcination temperature.

The pigment mix synthesized was applied as a coating to different substrates such as aluminum, glass and Mild steel. The results revealed that spectral selectivity of TSSS paint coatings based on the CoMnCu spinel ceramic mix was much better than that of solvent-based coatings for high-temperature applications. The presence of cement as an inorganic binder makes the functioning and application of paint easy as it becomes that of a waterborne type.

Ease of application, stability at high temperatures, best absorptivity at the solar selective spectrum and excellent adhesion properties for the selected surface are the key features of the designed pigment system. The applied pigment mix was studied as a coating to get the results for solar selective system.

Tankfreight Ltd., of Harrogate, part of the employee‐owned National Freight Consortium, has been awarded a major contract by Vinyl Products on the basis of their ability to offer an extremely economical all‐round package.