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carboxy acrylics compatibility with conventional electrostatic powder coating systems
One of the big advantages of the SC Johnson hydroxy and carboxy acrylics is their compatibility with conventional electrostatic powder coating systems. This makes it possible for custom coaters to use powders formulated with these chemistries on their application lines without fear of major contamination problems. Hydroxy acrylic / IPDI systems can be formulated over a relatively wide gloss range. In lower gloss versions,they easily pass the new weathering requirements of the automotive industry . This makes them the preferredRead More …
Carboxy acrylics are intended to meet the new demands of automotive industry
Several types of acrylic resins have been introduced since the mid 1980s. Capable of producing powders that are highly weatherable, they are intended to meet the new demands of the automotive industry. Carboxy acrylics Carboxy acrylics/TGIC combinations never really showed significant weatherability improvements over carboxy polyester TGIC systems,and the general concern about the use of TGIC has just about killed off this chemistry. Carboxy acrylic / HAA combinations ,which have recently been promoted ,offer another possibility for this class ofRead More …
Acrylic graft copolymers free glycidyl groups-glycidyl methacrylate(GMA)
TGIC Replacement chemistries Acrylic graft copolymers containing free glycidyl groups These hardeners,which include glycidyl methacrylate(GMA) curatives have recently been promoted as crosslinkers for carboxy polyester. Since the cure mechanism is an addition reaction, film builds that exceed 3 mils(75 um) are possible. So far, accelerated weathering tests of polyester GMA combinations indicate results similar to those of TGIC. Some formulating problems exist when acrylic graft copolymers are used ,for example, flow and leveling properties are relatively poor. New carboxy polyesterRead More …
TGIC Replacement chemistries-Tetramethoxymethyl glycoluril (TMMGU)
TGIC Replacement chemistries Tetramethoxymethyl glycoluril (TMMGU) Hydroxyl polyester/TMMGU combinations,such as powderlink 1174,developed by Cytec, may offer an excellent opportunity to replace TGIC in applications that require thinner film builds. As this chemistry’s cure mechanism is a condensation reaction, some of the application problems described in the section on HAA curatives also occur with this curative. However, recent evaluations and data show that pin hole free coatings can be obtained with hydroxyl polyester / TMMGU combinations even when film builds exceedRead More …
TGIC replacement chemistries in powder coating-Hydroxyalkylamide(HAA)
TGIC Replacement chemistries Hydroxyalkylamide(HAA) As the future of TGIC is uncertain,manufacturers are searching for an equivalent replacement for it. HAA curatives such as Primid XL-552 ,developed and trademarked by Rohm and Haas,have been introduced. The chief drawback to such hardeners is that, since their cure mechanism is a condensation reaction, films that build to thicknesses exceeding 2 to 2.5 mils (50 to 63 microns) may display outgassing ,pinholing ,and poor flow and leveling . This is especially true when theseRead More …
Characteristics of electrostatic powder coating spraying
Electrostatic powder coating spraying because he does not use the solvent will not cause solvent pollution in the atmosphere, while avoiding the danger of fire due to the solvent, is also easy to transport and storage of raw materials. The spraying process, the overspray powder is not coated on the workpiece can be recovered, the recovery rate of up to more than 95%, to improve the utilization of raw materials, to reduce the material consumption costs. Superior film performance, betterRead More …
Characteristics of the electrostatic spraying
Generally speaking, where does not occur at 200 ℃ deformation, enables the charged powder particles are adsorbed on the surface to be painted, the surface coating can be by electrostatic powder spraying. Therefore, electrostatic powder coating spraying technology can be widely used instruments, household appliances, mechanical and electrical equipment, automobile and shipbuilding, light industry equipment, furniture, machinery and building materials, and other metal parts of the surface protection and decorative painting. View from currently used in spray technology, electrostatic powderRead More …