Huihong Pigment: Introduction of New Antirust Pigment

The research of new anti-rust pigments has always been a hot spot in the anti-corrosion industry. At present, the products on the market are uneven, and the performance differences are relatively large. Many people think that a simple combination of shielding anti-rust pigments and corrosion-inhibiting anti-rust pigments can also achieve a good anti-rust effect. In fact, it is necessary to fully understand the properties of various anti-rust pigments and pass experimental tests to achieve the best anti-rust effect. Listed below are several common new pigments.

Modified Phosphate Series Antirust Pigments

The practical application of traditional zinc phosphate has been greatly limited. Its particle size is too large, its dispersion performance is not ideal, and it is easy to crystallize. The main thing is that its early anti-rust performance is not ideal, and it is difficult to avoid flashing in water-based coatings. The problem of rust is still very different from the rust-proof effect of lead-based and chromium-based anti-rust pigments. However, the anti-rust performance and anti-rust mechanism have given us great inspiration, so many excellent anti-rust pigments have been developed on this basis.

It has been found abroad that there is rust prevention between calcium borosilicate, calcium strontium phosphosilicate, zinc strontium phosphosilicate, zinc phosphate, zinc molybdate, zinc oxide, zinc nitrophthalate and zinc salt of benzoic acid. Enhancement; the U.S. Navy has developed a new, self-priming, glossy Dedicated Metal (DTM) (aluminum and steel surface) coating for use on aircraft using zinc molybdate, zinc phosphate, and a small amount of zinc benzoate The mixed anti-rust pigment synergistic system, and replaced the original anti-rust paint of zinc chromate, its effect is excellent, and in the water-based epoxy primer, its anti-rust pigment system uses zinc phosphate, zinc salt of nitro compound , Aluminum zinc phosphate hydrate mixing system. Since the zinc salt of the nitro compound is more water-soluble than the zinc phosphate, it overcomes the disadvantage that the initial anti-corrosion effect of the pigment such as zinc phosphate is not strong, and the aluminum zinc phosphate hydrate also increases the zinc content and the phosphate ion concentration for the same reason. The anti-corrosion time of the anti-corrosion system is extended. These examples show that as long as the combination is reasonable, the performance of the composite anti-rust pigment can completely achieve the anti-rust effect of lead-based and chromium-based anti-rust pigments.

Introduction of new anti-rust pigments

Ion exchange type antirust pigment

It is a calcium ion-exchange type silica gel anti-rust pigment of heavy metal mainly developed by Grace Co., Ltd. When the corrosive electrolyte is used to enter the coating film, that is, in contact with the anti-rust pigment, the pigment intercepts the corrosive ions on the silica surface and releases the corresponding calcium ions to transfer to the metal substrate. When the process is continued, the calcium ion layer will accumulate on the interface between the metal and the coating, so as to play a blocking role to protect the substrate, enhance the adhesion of the coating, and greatly enhance the anti-corrosion performance of the coating. However, the price of such anti-rust pigments is generally high, and the oil absorption is too large. Secondly, due to its alkalescence, it is easy to adsorb the activity of the acid catalyst, which affects the curing of the coating. So it greatly affects its use.

In view of the characteristics of this type of anti-rust pigment, in order to solve its defects in the use process, Anhui Aobang New Materials Co., Ltd. has developed an inorganic silicate anti-rust pigment ABR series of vertical titanium powder, which is based on silica As the main body, surface modification is carried out to make it active. When corrosive factors such as chloride ions, water and oxygen are eroded to the steel surface, when Fe is oxidized and corroded, the critical surface between the coating and the substrate forms a micro-battery. At this time, the active ingredients on the silicon dioxide are activated, so that the silicon dioxide is partially dissolved into silicate ions, and the silicate ions react with iron ions to form iron silicate, which is deposited on the surface of the substrate and coated. In the voids of the layer, while protecting the substrate, it also effectively enhances the compactness of the coating.