Compositions: coating or plastic – Coating or plastic compositions – Corrosion inhibiting coating composition
Patent
1992-12-14
1994-07-05
Group, Karl
Compositions: coating or plastic
Coating or plastic compositions
Corrosion inhibiting coating composition
106 1405, 106424, 106419, 106429, A04B 902
Patent
active
053263898
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTIVE SUMMARY
The invention concerns an anti-corrosive pigmentary composition for coating characterized in that it contains zinc 8 -hydroxy-quinolate.
According to a preferred embodiment, the composition according to the invention is made of a pigment pulverulent mixture including, in combination, the percentage being expressed in relation to the total weight of the pigment mixture; phosphate, iron phosphate, chromium phosphate, manganese phosphate, aluminum phosphate, aluminum oxide, calcium ferrite, zinc ferrite, magnesium ferrite, barium ferrite, iron ferrite, calcium borosilicate, barium borosilicate, calcium phosphosilicate, barium phosphosilicate, the complement consisting in pigment known in that type of application.
Application to anti-corrosive coatings, in particular for shipbuilding and protection of metal industrial works.
The present invention concerns an anti-corrosive pigmentary composition for painting coatings.
The invention applies more particularly to anti-corrosive coatings in particular for shipbuilding and protection of metal industrial works.
Paintings are the most usual means of protection against the risk of corrosion. They are generally pigment mixtures insoluble in suspension in a liquid medium, generally organic, and polymeric binders. After application on the substrate to be covered, the mixture hardens and leaves a solid film, adhering to the surface to be protected.
The most efficient pigments and the most often used on metal substrates are minimum and zinc chromate.
However, the legistlation recently brought into force in several European countries and the world over, have constrained the painting and varnish industry to replace the traditional anti-corrosive pigments , generally toxic, by products less dangerous for health and environment.
Thus anti-corrosive paintings containing more than 1% of strontium or zinc chromate must have a label indicating the risk of cancer in connection with their use.
The compositions containing heavy metals such as lead compounds, in particular minimum, are also subjected to a dissuasive legislation regarding their use.
The harmful effects of this toxicity on the environment and the expenses necessary for the protection of people in contact with these products are very important.
Much research has been carried out, in order to discover anti-corrosive pigments at the same time as efficient and as universally used as the strontium or zinc chromates, but less toxic for man and less harmful for the environment.
The use of zinc phosphates was initially proposed. It is usually admitted, and it has been shown by experience that, in spite of its interesting properties, this product is not in itself sufficient enough to achieve anti-corrosive performance at the level of that obtained with zinc chromates.
On contrary, presently, in commerce, there is a multiplication of pigmentary compositions containing zinc phosphates said to be "activated" by various organic substances or by various metal salts such as compounds with an aluminum, molybdenum, calcium base.
Unfortunately, the results achieved with anti-corrosive paintings containing the previously mentioned pigments are often disappointing as they are not long-lasting, due to the fast exhaustion of the activating agents by dissolution or decomposition.
Moreover, if some compositions are sometimes efficient in a given family of polymeric binders, this efficiency is generally lost when they are introduced in another family of polymeric binders.
In addition, many pigmentary compositions of this type often lead to a bad storage stability of the corresponding painting, by increase of viscosity and feeding-up.
The purpose of the invention is to offer anti-corrosive pigmentary compositions allowing to compensate for the above mentioned disadvantages, and particularly, presenting the following properties: equal volume concentration, and for a similar binder, containing for example acrylic, vinyl binders, alkyde resins, epoxy resins, polyurethanes, chlorinated rubber,
The anti-corrosive pigmentary compo
REFERENCES:
patent: 4871532 (1989-10-01), Hoogendoorn
patent: 5226956 (1993-07-01), Askels et al.
patent: 5244738 (1993-09-01), Seibel
K. Konno et al, "Chemical and Electrochemical Modifications of Zinc Using Organic Compounds", Plating and Surface Finishing, vol. 74, No. 10, Oct. 1987, pp. 40-44.
Etat Francais (represente par le Delegue General pour l'Armement
Gallo Chris
Group Karl
LandOfFree
Anti-corrosive pigmentary composition for coatings does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Anti-corrosive pigmentary composition for coatings, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Anti-corrosive pigmentary composition for coatings will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-793972