RU2533388C2 - Moderately alkaline, thin, inorganic, anti-corrosion coating for metal substrates - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to the protection of metal surfaces against corrosion. Dried in a place, an anti-corrosion coating has morphology, including a continuous inorganic phase, containing from 9 to 73 wt % in terms of the total weight of dry solid substances of the coating, of, at least, one element of the IVB group of the Periodic table and a source of chrome in accordance to one of the versions of the coating, as well as a discrete phase, containing from 1 to 73 wt % in terms of the total weight of the dry solid substances of the coating of active solid substances of the organic polymer, dispersed in a continuous inorganic phase. A conversion composition for coatings includes an inorganic part, containing from 9 to 73 wt % in terms of the total weight of the dry solid substances of the coating of, at least, one element of the IVB group of the Periodic table and the source of chrome, as well as an organic part, containing from 1 to 73 wt % in terms of the total weight of the dry solid substances of the coating of the active solid substances of the organic polymer, in the form of discrete polymer balls. The coatings by the invention have a unique morphology, including two different phases, and provide good mouldability despite the high apparent solidity, an excellent adhesion to metals and alloys, such as iron- zinc- and aluminium-based metals and alloys, as well as the high chemical and corrosion resistance.

EFFECT: coatings, which additionally include chrome, are not subjected to chrome leaching and possess the considerably higher corrosion resistance in comparison with the known chrome-based coatings.

23 cl, 5 dwg, 25 tbl

Description

Related Applications

This application is a partial continuation of the known application No. PCT / US2009 / 044504 with an international filing date of May 19, 2009 stating the priority of provisional application US No. 61/054363, filed May 19, 2008

Regulation on Federal Research Subsidies

Absent.

FIELD OF THE INVENTION

The present invention generally relates to corrosion protection of metal substrates, and more particularly, to a neutral or moderately alkaline, fine, inorganic, in-situ dried coating composition that can be applied directly to a metal substrate without prior treatment, for example with a phosphating solution, and which provides enhanced corrosion protection of the metal substrate. The in-situ dried coatings of the present invention, when dried in-place, also provide a unique morphology including a continuous inorganic phase and a discrete dispersed polymer phase.

State of the art

Unprocessed metal surfaces are susceptible to corrosion, which can lead to rust, weakening, discoloration, and destruction of the surface. Thus, metal substrates are usually treated in various ways, making the surface less reactive and more corrosion resistant. In addition, metal surfaces are then often coated with decorative or additional protective coatings, such as plastic coatings, primers, paints and other surface treatments. The initial treatment of a metal surface often involves metal phosphate treatment followed by washing with a chromium-containing liquid.

Metal parts, the surfaces of which are treated and coated by various means, can be divided into several categories. For some industrial purposes, the metal is formed in the form of a three-dimensional part, after which any combination of various types of surface treatment and / or coating can be used. In the second category of industrial use, the processing of metal surfaces and / or the coating of it is carried out before formation, when the metal has the form of a flat smooth sheet, which is usually rolled up. For many types of coatings in this category, special properties are desirable to facilitate rolling and forming operations. For coatings such as organic passives, a high degree of hardness and resistance to sticking may be desirable in order to facilitate rolling, however, known coatings having high hardness often have poor formability, leading to the integrity of the coating and, ultimately, its corrosion resistance is deteriorated as a result of fashioning operations. It is desirable to obtain coatings having both high hardness and good formability.

It is advisable to develop a corrosion-resistant coating composition, which is inorganic and can be used in neutral or moderately alkaline conditions. It is also important to develop a coating composition that does not impede the subsequent use of other types of decorative surface treatments that have been used in the past. For many years, metal coatings, such as organic passivating coatings, have used hexavalent chromium stemming due to its ability to inhibit corrosion. However, hexavalent chromium is less in demand in the market for environmental reasons. Over time, coatings containing trivalent chromium have become more widespread due to lower levels of environmental pollution compared to products based on hexavalent chromium. In many cases, such a replacement occurred at the expense of corrosion resistance. It is always desirable to improve the performance of coatings, such as corrosion resistance. This applies to any coating, such as hexavalent chromium based coatings. It is even more desirable in a similar way to improve performance, such as corrosion resistance, of coatings based on non-hexavalent chromium, for example, coatings based on trivalent chromium or coatings based on non-chrome. It is also undesirable for coatings including chromium to leach chromium into the environment.

Disclosure of invention

In General terms, the present invention relates to a neutral or moderately alkaline, inorganic composition for coatings, which can be applied directly to a metal surface without prior phosphating and which provides significant protection against corrosion. The coatings of the present invention, when dried in situ, also provide a unique morphology comprising two distinct phases. The first phase is a continuous inorganic phase obtained from water-soluble inorganic components. The second phase is a dispersed phase containing a polymer dispersion in the first phase. Such morphology provides a number of desirable distinctive features of the coating. Such distinguishing features include good formability, despite high apparent hardness, excellent adhesion to metals and alloys, such as metals and alloys based on iron, zinc and aluminum, as well as high chemical and corrosion resistance. Embodiments of the present invention, i.e. coatings that additionally include chromium are not susceptible to chromium leaching and have significantly higher corrosion resistance compared to known coatings based on chromium.

The coating compositions obtained according to the present invention preferably have a pH of from about 6 to 11, more preferably from 8 to 10. In one embodiment, the coating composition according to the present invention includes a source of at least one of the transition metals of the group IVB of the Periodic Table, namely zirconium, titanium and hafnium, and, optionally, a source of at least one of the transition metals of group VB of the Periodic Table, namely vanadium, niobium and tantalum. The coating composition preferably comprises from 9 to 73% by weight. based on the total weight of dry solids of the coating of at least one element of group IVB of the Periodic table. A preferred element of group IVB is zirconium, preferably used in the form of zirconium ammonium carbonate. The preferred element of group IVB is vanadium, used as V ₂ O ₅ . The coating composition also includes an organic polymer, in which the weight percent of active solids of the organic polymer, based on the total weight of the dry solids of the coating, is from 1% to 75%.

In another embodiment, the coating composition of the present invention includes a source of at least one of the transition metals of Group IVB of the Periodic Table, namely zirconium, titanium and hafnium, and a chromium source. The coating composition preferably comprises from 9 to 73% by weight. based on the total weight of dry solids of the coating of at least one element of group IVB of the Periodic table. A preferred element of group IVB is zirconium, preferably used in the form of zirconium ammonium carbonate. In this embodiment, the coating composition comprises a chromium source, such as chromium trioxide. The coating composition also includes an organic polymer, in which the weight percent of active solids of the organic polymer, based on the total weight of the dry solids of the coating, is from 1% to 75%.

The coating compositions of the present invention are in situ dried conversion coatings. Such a coating is highly versatile, since a wide variety of organic polymers can be introduced into it, which can be added directly to the coating composition, thereby eliminating the need for multi-stage coating processes, while the corresponding synthetic polymers are dispersible or soluble in inorganic aqueous coating composition. In addition, such a coating has significant formability and hardness. Since the coating is conversion in the sense that is included in this term in the art, the components of the coating composition interact with the metal substrate during the coating process, providing a final, dried in situ coating.

Mentioned and other features and advantages of the present invention will become more apparent to those skilled in the art from a detailed description of a preferred embodiment thereof. Drawings illustrating the detailed disclosure are described below.

Brief Description of the Figures

Figure 1A is a photograph of a dark background of a chromium-based coating obtained according to the present invention, taken under a scanning transmission electron microscope;

Figure 1B represents a stronger increase in coverage from Figure 1A;

Figure 2A is a photograph on a dark background of a chromium-free coating obtained according to the present invention, taken under a scanning transmission electron microscope;

Figure 2B represents a stronger increase in coverage from Figure 2A; and

figure 3 is a photograph on a dark background of a known commercial chromium-based coating obtained not in accordance with the present invention, taken under a scanning transmission electron microscope.

Detailed Description of a Preferred Embodiment

The present invention relates to the treatment of uncoated metal surfaces; this means that the metal surface is not subjected to pre-treatment with any metal phosphate solutions containing chromium washes, or any other kind of passivating treatment. Metal surfaces that benefit from the process of the present invention include steel, cold rolled steel, hot rolled steel, stainless steel, aluminum, steel coated with zinc metal or zinc alloys such as electro galvanized steel, galvalume®, galvanneal and hot galvanized steel.

Before processing according to the present invention, the metal surface is preferably cleaned and degreased. Cleaning metal surfaces is well known in the art and may include the use of soft or strong alkaline cleaning agents. Examples of two alkaline cleaning agents include Parco® Cleaner ZX-1 and Parco® Cleaner 315 from Henkel Surface Technologies. After cleaning, before processing, according to the present invention, the surface is preferably washed with water.

In one embodiment, the corrosion protection coating of the present invention comprises a mixture of at least one element of group IVB and at least one element of group VB in deionized water at a pH of about 6 to 11, more preferably at pH equal to from 8 to 10. For the implementation of the coating process, it is important to maintain the pH of the composition within this range. In one embodiment, an element of group IVB is preferably present in an amount of from 1 to 7% by weight, more preferably from about 2 to 5% by weight, and most preferably from 3 to 5% by weight. composition based on the total weight of the composition. The coating composition may include any sub-range of 1 to 7% by weight. calculated on the total weight of the composition. In this embodiment, the content of an element of group VB in the composition is preferably from about 0.20 to 2.00% by weight, more preferably from about 0.40 to 1.00% by weight. calculated on the total weight of the composition. The coating composition may include any sub-range of 0.20 to 2.00% by weight. calculated on the total weight. The coating composition is preferably a mixture of zirconium and vanadium. One preferred source of zirconium is zirconium ammonium carbonate, called Bacote 20® and manufactured by MEI, Flemington, New Jersey. As described by MEI, Bacote 20® is a clear aqueous alkaline solution of stabilized zirconium ammonium carbonate containing anionic hydroxylated zirconium polymers. This ensures the presence of approximately 20% w / w. ZrO ₂ . It is marketed as a crosslinking agent for paper and paperboard. The preferred element of group IVB is vanadium, used as V ₂ O ₅ . Organic synthetic polymers for coatings of various kinds can also be incorporated into the coating described, including, by way of example only, epoxides, polyvinyl dichlorides, acrylic resins, methacrylate resins, styrene resins, polyurethane dispersions and hybrids of polyurethane dispersions. Examples of such synthetic polymers include Carboset®, Hauthane HD-2120, Hauthane L-2989, Maincote ^TM PR-15, Maincote ^TM PR-71, Avanse MV-100, Rhoplex AC 337N, and Alberdingk-Boley LV-51136 and M-2959 . This coating also allows the introduction of V ₂ O ₅ reducing agents, such as cysteine, Sn ²⁺ , ascorbic acid or thiojuccinic acid. Optionally, V ⁺⁴ from vanadyl sulfate or vanadyl acetylacetonate may be used as starting material. Such a coating may also optionally include processing aids, such as various kinds of waxes, which contribute to the formability of the coated substrates. The administration of such optional agents is described below.

In the first example, the inorganic coating composition of the present invention is prepared by combining 83.00% by weight. deionized (DI) water with 1.00% weight. V ₂ O ₅ and 16.00% by weight. Bacote 20®. This amount of Bacote 20® provides a content of 3.2% by weight. ZrO ₂ in the composition. The pH of the composition is approximately 9.5. The inorganic coating is applied to a series of hot-dip galvanized (HDG) panels, known as AST HDG APR 31893 panels, and US Steel Corp. panels. (USS) of Galvalume®, using a known method using a stretched wire for coating in the amount of 200 milligrams per square. ft (200 milligrams per 929.03 square centimeters). Galvalume® is the trade name for aluminum-zinc alloy coated sheet steel. After application, the coating is dried in place to a peak metal temperature (PMT) of 210 ° F (98 ° C) on the test panels. The panels are then subjected to a neutral salt spray (NSS) corrosion test on several panels at each point in time according to ASTM Method B117-03. In this study, uncoated panels of HDG or USS Galvalume® showed 100% corrosion within 24 hours in an NSS test. The test results in the form of the average percentage level of corrosion of each of the treated panels are shown below in table 1.

Table 1 Time, hours (NSS) 24 48 144 312 480 649 816 1008 HDG 70.00 USS Galvalume® 0.00 00.00 0.00 4.00 13.00 13.00 22.00 25.00

The results obtained show the advantages of the coating composition obtained according to the present invention. It is obvious that the coating composition according to the present invention is very effective for USS Galvalume® steel, providing its significant corrosion protection for more than 1008 hours. These results are very different from the USS Galvalume® uncoated steel test results, which were 100% corroded within 24 hours. The test results of the HDG substrate were also significant, but not so high.

As mentioned above, another advantage of the described coating composition is that it readily allows the incorporation of organic resins to further improve corrosion protection without requiring complex multi-stage processing or application. The desired resin can simply be incorporated into the coating composition. In the first example of mixing an inorganic coating composition with an organic resin, polyvinyl dichloride (PVDC) was used as the organic resin. The PVDC resin used is Noveon XPD-2903. A number of coating compositions were prepared as described in Table 2 below.

table 2 Component Composition 57B Composition 57C Composition 57D Deionized water 73.50 63.50 53.50 Bacote 20® 16.00 16.00 16.00 V ₂ O ₅ 0.50 0.50 0.50 PVDC 10.00 20.00 30.00

Each composition is then applied to a series of HDG panels and a series of USS Galvalume® panels using the in-place drying process described above and coating at 200 milligrams per square meter. ft (200 milligrams per 929.03 square centimeters), and dried to a RMT of 210 ° F (98 ° C). A series of HDG control panels and USS Galvalume® panels were prepared using a commercially available, chromium-free Granocoat® 342 ^TM (G342) coating manufactured by Henkel. G342 is applied according to the manufacturer's instructions. In the first test, the panels are subjected to the NSS test described above, after which the percentage of corrosion of several panels at each time point is determined and the average value is derived. The results are presented below in table 3, in which the reduction of Gal. Means USS Galvalume® panels.

Table 3 Time, hours (NSS) G342 Gal. 57B Gal. 57C Gal. 57D Gal. G342 HDG 57B HDG 57C HDG 57D HDG 24 0.10 0,03 0.00 0.00 0.00 1.10 0.13 0.77 48 0.10 0,03 0.00 0.00 0.20 1.10 0.30 2.67 72 0.33 0.33 0.00 0.00 0.67 1,67 4.33 3.00 96 0.67 0.33 0.00 0.00 2.67 3.67 8.67 7.33 168 5.00 1.00 0.00 0.00 17.00 8.67 18.33 20.00 336 13.33 1.00 0,03 0.05 63.33 35.00 56.67 43.33 504 48.67 2.67 0.33 0.50 60.00 75.00 70.00 672 76.67 2.67 2,33 1.00 840 3.00 4.33 3.00 1200 10.67 9.00 3.00

The above results finally demonstrate the improved corrosion protection afforded by the coating composition of the present invention. By analyzing USS Galvalume® panel data, we can see an improvement in corrosion protection for all panels compared to the G342 control after 168 hours of testing, with differences increasing as the duration of the test increases. After 504 hours of testing, the corrosion level of the coated panels according to the present invention is 18 to 147 times less than the control panels G342. After 840 hours, the corrosion level of the G342 control panels is 28-76 times higher than the corrosion level of the coated panels of the present invention. Even after 1200 hours of testing, the corrosion level of the coated panels of the present invention is only 3 to 11%. Such results are striking and show the effectiveness of the coating composition obtained according to the present invention. These results also show that increasing the level of polyvinyl dichloride from 10% to 30% has little effect on the degree of corrosion protection at the last moment in time. With regard to data on HDG panels, it is obvious that the coatings according to the present invention also provide improved protection compared with G342 up to approximately 504 hours. The results for HDG panels are not as striking as the results for panels from USS Galvalume®. In addition, the effect of increasing the level of polyvinyl dichloride seems to be the opposite of that observed with USS Galvalume® panels. The higher the content of polyvinyl dichloride, the lower the corrosion protection of HDG coated panels.

In the following group, USS Galvalume® or HDG panels tested for corrosion are coated as described above using the formulations of Table 2 in an amount of 200 milligrams per square meter. ft (200 milligrams per 929.03 square centimeters), and dried in place, on the panels, to a PMT of 210 ° F (98 ° C). A stacking test is then carried out, simulating the contact of the panels together in a humid environment. The stacking test is carried out by spraying deionized water on the coated side of the first panel, placing the coated side of the second panel on the coated side of the first panel, and then bonding the first and second panels together. The panels bonded together are then placed in a moisture test chamber at 100 ° F (38 ° C) and 100% humidity. At various points in time, several panels in each state are removed from the chamber, the percentage level of corrosion of each panel is determined, and the results are averaged. The average results are presented below in table 4.

Table 4 Time, hours (stack) G342 Gal. 57B Gal. 57C Gal. 57D Gal. G342 HDG 57B HDG 57C HDG 57D HDG 168 3.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 336 5.00 0.00 0.00 0.00 5.00 3.00 1.00 1.00 504 5.00 0.00 0.00 7.00 5.00 3.00 3.00 5.00 672 7.00 0.00 1.00 8.00 5.00 5.00 10.00 16.00 840 8.25 0.50 1.00 12.00 10.00 16.00 25.00 30.00 1200 10.00 2.00 3.00 12.00 50.00 40.00 60.00 60.00 1344 10.00 2.00 3.00 16.00 1512 10.00 2.00 3.00 20.00 1680 10.00 3.00 7.00 23.33 1848 20.00 5.00 7.00 30.00 2016 22.50 5.00 10.00 40.00

The results show that with a resin content of 10 and 20%, the coating composition according to the present invention turned out to be much more effective than the G342 coating at all times 16-2.2 times depending on the point in time. However, a coating containing 30% PVDC after 1200 hours was not as effective as the G342 control panels, and after 2016 hours it turned out to be almost twice as corroded than the control panel. The reason for this difference is unknown. Regarding HDG panels, the results show a smaller difference between the control panels and the coatings according to the present invention. All panels exhibit good corrosion protection for 504 hours. Then, coating compositions containing 20 and 30% PVDC were less effective than G342 panels and than panels containing 10% PVDC.

In the following group, USS Galvalume® or HDG panels tested for corrosion are coated as described above using the formulations of Table 2 in an amount of 200 milligrams per square meter. ft (200 milligrams per 929.03 square centimeters), and dried in place, on the panels, to a PMT of 210 ° F (98 ° C). The panels are then subjected to the Cleveland Moisture Test (STN) using the ASTM D4585 method. The results are presented below in table 5.

Table 5 Time, hours (SNT) G342 Gal. 57B Gal. 57C Gal. 57D Gal. G342 HDG 57B HDG 57C HDG 57D HDG 168 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 336 7.00 3.00 0.00 0.00 7.00 3.00 0.00 0.00 504 7.00 3.00 0.00 0.00 10.00 3.00 0.00 0.00 672 7.00 3.00 0.00 0.00 10.00 3.00 0.00 840 7.00 3.00 0.00 0.00 10.00 3.00 1.00 1200 7.00 7.00 1.00 0.3 16.00 5.00 5.00

The results obtained using USS Galvalume® show that the coating composition of the present invention was much more effective than the control coating G342, with the exception of the result obtained after 1200 hours, with a content of 10% PVDC equal to the result of the control G342. The results obtained clearly show that increasing the PVDC content has a very good effect on the corrosion protection of the coating obtained according to the present invention. Similar results are observed when using coated HDG panels according to the present invention, providing a much higher level of corrosion protection compared to G342. In addition, increasing the PVDC content appears to improve corrosion protection.

In the following group, USS Galvalume® or HDG panels tested for corrosion are coated as described above using the formulations of Table 2 in an amount of 200 milligrams per square meter. ft (200 milligrams per 929.03 square centimeters), and dried in place, on the panels, to a PMT of 210 ° F (98 ° C). The panel group is then subjected to a Butler water immersion test (BWI). Each test panel, while supporting, is immersed in a tank of distilled water so that under each panel is half an inch of water, and above each panel is three quarters of an inch of water. The tanks with the panels are then placed in a humidity chamber with a humidity of 100% and a temperature of 100 ° F (38 ° C). The panels are removed at selected points in time and the percentage of their corrosion is determined. The results are presented below in table 6.

Table 6 Time, hours (BWI) G342 Gal. 57B Gal. 57C Gal. 57D Gal. G342 HDG 57B HDG 57C HDG 57D HDG 168 0.00 0.00 1.00 0.00 0.00 1.00 0.00 0.00 336 0.00 0.00 1.00 1.00 16.00 1.00 0.00 1.00 504 0.00 0.00 1.00 1.00 50.00 1.00 0.00 3.00 672 3.00 0.00 1.00 1.00 1.00 0.00 3.00 840 7.00 7.00 1.00 3.00 7.00 7.00 7.00 1200 16.00 7.00 3.00 10.00 25.00 16.00 10.00 1344 16.00 7.00 3.00 10.00 25.00 16.00 16.00 1572 20.00 7.00 3.00 10.00 30.00 16.00 16.00 1680 20.00 7.00 3.00 10.00 30.00 20.00 20.00 1848 25.00 7.00 3.00 10.00 30.00 20.00 25.00 2016 30.00 7.00 3.00 16.00 40.00 30.00 40.00

The results obtained using USS Galvalume® show that the coating composition obtained according to the present invention provides much stronger corrosion protection than the control coating G342. A stronger protection of approximately 2-10 times increases corrosion resistance compared to G342. The effect of the PVDC content on corrosion protection is complex and non-linear, with the highest content being less effective than the content of 10 to 20% by weight. HDG panels also show the advantage of the panels of the present invention over G342. All coated panels of the present invention have improved corrosion protection compared to G342. Again, the effect of the PVDC level is complex and appears to show the best results at 20% PVDC.

As mentioned above, the advantage of the described coating lies in the fact that it easily allows the introduction of organic resins in order to further improve corrosion protection without requiring complex multi-stage processing or coating. The desired resin can simply be incorporated into the coating composition. In a second example of a compound of an inorganic coating composition with an organic resin, a thermoplastic emulsion based on a styrene-acrylic copolymer called Carboset® CR-760 is used as an organic resin. Carboset® CR-760 is available from Lubrizol Advanced Materials, Inc., Cleveland, Ohio. Carboset® CR-760 contains approximately 42% by weight. dry matter. In additional coatings, Carboset® CR-760 is also combined with PVDC, the use of which is described above. In additional compositions, the coating composition also includes an emulsion of carnauba wax to improve the formability of the coating composition. The carnauba wax emulsion is Michem®, Lube 160 manufactured by Michelman, Inc., Cincinnati, Ohio. A series of coating compositions was prepared, described in Table 7 below. Each composition was then applied to a series of HDG panels and a series of USS Galvalume® panels using the in-place drying method described above, with a coating weight of 175 to 180 milligrams per square meter. ft (175 to 180 milligrams per 929.03 square centimeters), and dried to a RMT of 210 ° F (98 ° C). In a first corrosion test, the panels are subjected to the NSS test described above and the percentage corrosion of several panels at a time is determined. The average results for each point in time are presented below in table 8. Samples of composition 162B in NSS are not available. Additional panels were used to evaluate coatings using the Butler water immersion tests described above, the Cleveland Moisture Test, and stacking tests. The results of the tests are presented below in tables 9, 10 and 11, respectively.

Table 7 Component 162A 162V 162C 162D Deionized water 32,50 26.00 39.50 33.00 Bacote 20® 16.00 16.00 16.00 16.00 V ₂ O ₅ 0.50 0.50 0.50 0.50 Carboset® CR760 51.00 51.00 26.00 26.00 PVDC 18.00 18.00 Carnauba wax 6.50 6.50

Table 8 Time, hours (NSS) 162A Gal. 162B Gal. 162C Gal. 162D Gal. 162A HDG 162B HDG 162C HDG 162D HDG 24 0.00 0.00 0.00 0.00 0.00 7.00 7.00 48 0.00 0.00 0.00 0.00 23.66 16.00 20.00 168 0.00 1.00 0.70 0.00 100.00 86.67 93.33 336 0.00 3.33 8.67 0.00 504 1.00 5.67 6.00 0.00 672 1.00 8.67 10.00 0.00 840 1.00 8.67 10.00 1.00 1008 1.00 15.00 16.00 1.00 1176 1.00 20.00 25.00 5.00 1344 5.00 25.33 50.00 15.33 1512 5.67 28.67 17.33 1680 6.33 30.00 20.00 1848 6.33 23.33 20.00 2016 6.33 36.67 21.67

The results obtained using USS Galvalume® show that all coatings according to the present invention are more effective than G342, the results of which are presented above in table 3. The coating containing only Carboset® CR760 is very effective even for more than 2016 hours. Comparison of composition 162A with 162B shows that the addition of carnauba wax to this composition reduces the effectiveness of the coating as a corrosion-resistant coating. The results also show that combining Carboset® CR760 with PVDC reduces the effectiveness of the coating composition compared to using only Carboset® CR760, however, adding carnauba wax to this mixture seems to increase its effectiveness. None of the coatings are highly effective on HDG samples, and the presence of Carnauba wax or PVDC does not appear to affect the effectiveness of Carboset® CR760 alone.

Table 9 Time, hours (BWI) 162A Gal. 162B Gal. 162C Gal. 162D Gal. 162A HDG 162B HDG 162C HDG 162D HDG 168 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 336 1.00 1.00 0.00 0.00 0.00 0.00 0.00 0.00 504 3.00 3.00 1.00 1.00 0.00 3.00 5.00 5.00 672 5.00 3.00 3.00 1.00 1.00 5.00 5.00 5.00 840 5.00 5.00 3.00 1.00 1.00 7.00 7.00 10.00 1008 5.00 5.00 5.00 1.00 1.00 7.00 7.00 16.00 1176 16.00 10.00 10.00 1.00 1.00 1.00 16.00 20.00 1344 16.00 16.00 16.00 3.00 3.00 7.00 20.00 20.00 1512 16.00 16.00 20.00 3.00 3.00 10.00 25.00 30.00 1680 16.00 16.00 30.00 5.00 7.00 30.00 30.00 30.00 1848 16.00 16.00 30.00 5.00 7.00 30.00 50.00 50.00 2016 16.00 16.00 40.00 5.00 7.00 40.00

The results obtained using USS Galvalume® panels show that with the exception of the Carboset® CR760 and PVDC mixtures, all coatings are more effective than the G342 coating of Table 6. The BWI test did not show a decrease in the effectiveness of Carboset® CR760 alone. Unlike the NSS test, the combination of Carboset® CR760 with PVDC and Carnauba Wax proved to be the most effective in the BWI test. Again, as NSS test results show, it is beneficial to add Carnauba wax by combining Carboset® CR760 with PVDC. The results obtained using HDG panels also show that all coatings obtained according to the present invention are more effective than the coating G342 from table 6. Significantly higher efficiency was obtained using only Carboset® CR760 compared to the addition of carnauba wax, PVDC, or Carnauba wax and PVDC.

Table 10 Time, hours (STN) 162A Gal. 162B Gal. 162C Gal. 162D Gal. 162A HDG 162B HDG 162C HDG 162D HDG 168 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 336 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 504 3.00 3.00 3.00 1.00 0.00 3.00 5.00 5.00 672 3.00 3.00 3.00 2.00 0.00 3.00 5.00 5.00 840 3.00 3.00 3.00 3.00 1.00 3.00 5.00 5.00 1008 3.00 3.00 3.00 3.00 3.00 3.00 5.00 5.00

The results obtained using both USS Galvalume® panels and HDG panels show that in the Cleveland Moisture Test all coatings according to the present invention are equally effective, regardless of the substrate, and that they all exceed the results obtained using a control coating G342 described in table 5.

Table 11 Time, hours (stack) 162A Gal. 162B Gal. 162C Gal. 162D Gal. 162A HDG 162B HDG 162C HDG 162D HDG 168 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 336 0.00 1.00 0.00 0.00 0.00 0.00 1.00 1.00 504 0.00 1.00 1.00 1.00 5.00 5.00 10.00 7.00 672 0.00 3.00 1.00 1.00 10.00 20.00 30.00 16.00 840 1.00 5.00 1.00 3.00 10.00 20.00 30.00 37.50 1008 1.00 5.00 3.00 3.00 20.00 30.00 40.00 40.00 1176 1.00 5.00 3.00 5.00 30.00 40.00 1344 3.00 5.00 3.00 5.00 50.00 1512 3.00 7.00 3.00 5.00 1680 3.00 7.00 3.00 5.00 1848 3.00 7.00 3.00 5.00 2016 5.00 7.00 5.00 5.00

The results obtained using USS Galvalume® panels show that all coatings according to the present invention are equally effective in stacking tests and that they exceed the results obtained using the control coating G342 described in Table 4. The results of using HDG panels are different, with only Carboset® CR760 coating appearing to be the most effective and other coatings being less effective. None of the coatings was much more effective than the coating G342 from table 4.

In another series of tests, the content of zirconium ammonium carbonate in the coating is varied in order to change the amount of ZrO ₂ in the coating composition and the effect of such a change on corrosion protection is determined. Coating compositions are shown in Table 12 below. In addition, control panels are coated with G342 as described above. Coatings are applied to USS Galvalume® panels, with a coating weight of approximately 200 milligrams per square meter. ft (200 milligrams per 929.03 square centimeters), and dried to a RMT of 210 ° F (98 ° C). The panels are then tested with NSS, a Butler water immersion test, and a stacking test; the results obtained are presented below in tables 13, 14 and 15, respectively.

Table 12 Component 162A 162V 183A / F 183E Deionized water 32,50 26.00 40.50 42.50 Bacote 20® 16.00 16.00 8.00 6.00 V ₂ O ₅ 0.50 0.50 0.50 0.50 Carboset® CR760 51.00 51.00 51.00 51.00 Carnauba wax 6.50

Table 13 Time, hours (NSS) G342 162A 162B 183 A / F 183E 24 0.00 0.00 0.00 0.00 0.00 72 0.00 0.00 0.00 0.00 0.00 168 3.00 0.00 0.00 0.00 1.00 336 31.67 0.00 0.00 3.83 21.67 504 60.00 0.00 1.00 31.00 80.00 672 1.00 1.00 31,50 840 1.00 1.00 25.33 1032 1.00 1.00 35.33 1172 1.00 1.00 30.00 1344 1,67 3.00 40.00 1560 2.00 3.00 40.00 1728 4.00 5.00 50.00

The results show that all coatings according to the present invention are at least as effective as G342, and most of them are much more effective. The results also show that increasing the level of ZrO ₂ from 1.20% to 3.20% dramatically increases the effectiveness of the coatings obtained according to the present invention.

Table 14 Time, hours (BWI) G342 162A 162B 183 A / F 183E 168 0.00 0.00 0.00 0.00 0.00 336 0.00 0.00 0.00 0.00 0.00 504 0.00 0.00 1.00 0.00 1.00 672 0.00 1.00 3.00 0.50 3.00 840 0.00 3.00 3.00 0.50 3.00 1032 0.00 3.00 3.00 3.00 7.00 1176 10.00 5.00 5.00 4.00 10.00 1344 30.00 7.00 7.00 4.00 20.00 1512 50.00 7.00 7.00 5.00 20.00 1680 1.00 1.00 3.00 20.00 1848 3.00 3.00 5.00 20.00 2016 5.00 5.00 7.5 20.00

The results obtained again show that all coatings according to the present invention are much more effective than G342. In addition, although not as much as in the NSS test, the results show that increasing the ZrO ₂ content increases the effectiveness of the coating against corrosion.

Table 15 Time, hours (stack) G342 162A 162B 183 A / F 183E 168 0.00 0.00 0.00 0.00 0.00 336 0.00 0.00 0.00 0.00 0.00 504 1.00 1.00 0.00 0.00 0.00 672 1.00 3.00 0.00 0.00 1.00 840 3.00 3.00 1.00 2.00 1.00 1032 3.00 3.00 3.00 2.00 1.00 1176 3.00 5.00 3.00 3.00 3.00 1344 5.00 5.00 5.00 3.00 3.00 1512 7.00 5.00 5.00 4.00 5.00 1680 10.00 5.00 5.00 5.00 5.00 1848 10.00 5.00 5.00 6.00 5.00 2016 10.00 5.00 7.00 13.00 7.00

The obtained results also show that the coatings according to the present invention are more effective than the control G342, however, with an increase in the ZrO ₂ content, the same increase in efficiency is not observed as in other tests.

As described below, in the next series of tests, two additional resins 3272-096 and 3272-103 were obtained, after which the obtained resins were used, as described in detail in table 16 below, to obtain coatings according to the present invention.

Resin 3272-096

Resin 3272-096 includes, as monomers: acetoacetoxyethyl methacrylate (AAEM), n-butyl methacrylate, styrene, methyl methacrylate, 2-ethylhexyl acrylate and ADD APT PolySurf HP, which is a mixture of methacrylated mono- and di-phosphate esters. The total monomer distribution in the resin is as follows: 20.00% AAEM, 12.50% n-butyl methacrylate, 15% styrene, 27.50% methyl methacrylate, 20.00% 2-ethylhexyl acrylate and 5.00% ADD APT PolySurf HP. The resin polymerization reaction is carried out in an atmosphere of N ₂ with stirring and setting temperature during heating, component 80 ° C. The initial charge to the reactor is 241.10 grams of deionized (DI) water, 2.62 grams of ammonium lauryl sulfate (Rhodapon L-22 EP) and 2.39 grams of iron sulfate heptahydrate (P) FeSO ₄ 7H ₂ O (3 ppm) . After loading this initial mixture into the reactor, a countdown to the setting temperature begins. After 30 minutes, a seed is added to the reactor comprising a combination of 5.73 grams of DI water, 0.90 grams of a nonionic surfactant (Tergitol 15-S-20), 0.13 grams of ammonium lauryl sulfate (Rhodapon L-22 EP), 2, 15 grams of n-butyl methacrylate, 2.57 grams of styrene, 4.74 grams of methyl methacrylate, 3.48 grams of 2-ethylhexyl acrylate, 3.41 grams of acetoacetoxyethylmethacrylate (AAEM), and 0.85 grams of ADD APT PolySurf HP and continue heating to set point at for another 15 minutes. Then, the initial initiating mixture was loaded into a reactor containing 0.32 grams of HOSN ₂ SO ₂ Na, 4.68 grams of DI water, 0.45 grams of tert-butyl hydroperoxide and an additional 4.54 grams of DI water, maintaining the temperature at the set temperature for another 30 minutes. Then the monomer and initiating mixtures are loaded into the reactor for three hours, maintaining the temperature at the set temperature. The chargeable monomer includes 106.92 grams of DI water, 17.10 grams of Tergitol 15-S-20, 2.49 grams of Rhodapon L-22 EP, 40.89 grams of n-butyl methacrylate, 48.83 grams of styrene, 89.97 grams of methyl methacrylate 66.10 grams of 2-ethylhexyl acrylate, 64.77 grams of AAEM and 16.19 grams of ADD APT PolySurf HP. The initiating, co-charged mixture includes 0.97 grams of HOSN ₂ SO ₂ Na, 14.03 grams of DI water, 1.39 grams of tert-butyl hydroperoxide and an additional 13.61 grams of DI water. After three hours, the final mixture was added to the reactor over 30 minutes. Such a mixture contains 0.32 grams of HOSN ₂ SO ₂ Na, 4.88 grams of DI water, 0.46 grams of tert-butyl hydroperoxide and an additional 4.54 grams of DI water. Then the reactor is kept at the set temperature for one and a half hours. After this, cooling starts from the setting temperature, continues for two hours until the temperature reaches 38 ° C. Then the buffer mixture is loaded into the reactor. The buffer mixture contains 5.19 grams of ammonium hydroxide (28%) and 18.48 grams of DI water. For the preparation of this resin and resin 3272-103 described below, another potential phosphate-containing monomer that can be used in place of the ADD APT PolySurf HP is Ebecryl 168 from Radcure Corporation. Additional non-ionic surface stabilizers that can be used in place of Tergitol 15-S-20, which is a secondary alcohol ethoxylate, are other non-ionic stabilizers having a hydrophilic lipophilic balance of 15 to 18. Examples of such stabilizers include: other secondary alcohol ethoxylates, such as Tergitol 15-S-20; mixtures of ethoxylates, such as Abex 2515; polyglycol ether such as Emulsogen LCN 118 or 258; solid fatty alcohol ethoxylate such as Genapol T 200 and T 250; isotridecyl alcohol ethoxylates such as Genapol X 158 and X 250; tridecyl alcohol ethoxylates, such as Rhodasurf BC-840, and oleyl alcohol ethoxylates, such as Rhodasurf ON-877.

Resin 3272-103

Organic resin 3272-103 for coatings obtained in the following way. This resin includes, as monomers: acetoacetoxyethyl methacrylate (AAEM), n-butyl methacrylate, styrene, methyl methacrylate, 2-ethylhexyl acrylate and ADD APT PolySurf HP, which is a mixture of methacrylated mono- and di-phosphate esters. The total monomer distribution in the resin is as follows: 20.00% AAEM, 12.50% n-butyl methacrylate, 15% styrene, 27.50% methyl methacrylate, 20.00% 2-ethylhexyl acrylate and 5.00% ADD APT PolySurf HP. The resin polymerization reaction is carried out in an atmosphere of N ₂ with stirring and setting temperature during heating, component 80 ° C. The initial loading into the reactor is 286.10 grams of DI water, 2.47 grams of Rhodapon L-22 EP. After loading this initial mixture into the reactor, a countdown to the setting temperature begins. After 30 minutes, a seed was added to the reactor, including a combination of 5.44 grams of DI water, 0.85 grams of Tergitol 15-S-20, 0.12 grams of Rhodapon L-22 EP, 2.04 grams of n-butyl methacrylate, 2.44 grams styrene, 4.49 grams of methyl methacrylate, 3.30 grams of 2-ethylhexyl acrylate, 3.24 grams of acetoacetoxyethyl methacrylate (AAEM) and 0.81 grams of ADD APT PolySurf HP and continue heating to set temperature for another 15 minutes. Then, the initial initiating mixture was loaded into a reactor containing 4.79 grams of DI water and 0.21 grams of (NH ₄ ) ₂ S ₂ O ₈ , maintaining the temperature at 80 ° C for another 30 minutes. Then the monomer and initiating mixtures are loaded into the reactor for three hours, maintaining the temperature at the set temperature. The chargeable monomer comprises 103.36 grams of DI water, 16.15 grams of Tergitol 15-S-20, 2.35 grams of Rhodapon L-22 EP, 38.81 grams of n-butyl methacrylate, 46.34 grams of styrene, 85.38 grams of methyl methacrylate 62.73 grams of 2-ethylhexyl acrylate, 61.47 grams of AAEM and 15.37 grams of ADD APT PolySurf HP. The initiating, co-loading mixture includes 14.36 grams of DI water and 0.64 grams (NH ₄ ) ₂ S ₂ O ₈ . After three hours, the final mixture was added to the reactor over 30 minutes. Such a mixture contains 0.35 grams of ascorbic acid, 4.65 grams of DI water, 0.44 grams of tert-butyl hydroperoxide, an additional 4.56 grams of DI water and 2.39 grams of iron (II) sulfate heptahydrate FeSO ₄ 7H ₂ O (3 ppm). Then the reactor is kept at the set temperature for one and a half hours. After this, cooling starts from the setting temperature and continues for two hours until the temperature reaches 38 ° C. Then the buffer mixture is loaded into the reactor. The buffer mixture contains 5.88 grams of ammonium hydroxide (28%) and 18.48 grams of DI water.

Using the resins described above, a number of coatings are obtained in order to determine the effect of alkaline treatment on the coatings and the benefits of introducing V ₂ O ₅ plus a reducing agent, cysteine, into the coating. Other reducing agents for V ⁺⁵ may include Sn ⁺² or ascorbic acid, or thiosuccinic acid, or you can start with V ⁺⁵ from vanadyl sulfate or vanadyl acetylacetonate. Then, coatings from Table 16 are applied to the HDG panels, with the coating weight on each panel being approximately 200 milligrams per square meter. ft (200 milligrams per 929.03 square centimeters), then dried to a PMT of 200 ° F or 300 ° F (93 or 149 ° C), and either immediately tested with NSS or washed first with an alkaline PCI 338 cleaner and then tested with NSS. The reduction in corrosion protection after pretreatment with PCI 338 means that the coatings are not alkali resistant. The test results with NSS are presented below in table 17.

Table 16 Component 8A 8H 9A 9H Deionized water 66.00 66.00 65.00 65.00 Bacote 20® 24.00 24.00 24.00 24.00 V ₂ O ₅ 0.50 0.50 Cysteine 0.50 0.50 3272-096 10.00 10.00 3272-103 10.00 10.00

Table 17 Treatment Time, hours (NSS) 8A 8H 9A 9H PMT of 200 ° F (93 ° C), no PCI 338 processing 24 10.00 16.00 0.00 0.00 48 30.00 60.00 3.70 1.00 72 60.00 8.70 1.00 96 11.30 43.00 168 50.00 33.30 336 76.70 PMT 300 ° F (149 ° C), no PCI 338 processing 24 80.00 50.00 0.00 0.00 48 0.00 1.00 72 0.00 18.70 96 1.70 40.00 168 50.00 65.30 336 93.30 PMT equal to 200 ° F (93 ° C), processing PCI 338 24 20.00 16.00 7.00 3.00 48 50.00 60.00 50.00 30.00 72 60.00 50.00 50.00 96 50.00 168 50.00 PMT equal to 300 ° F (149 ° C), processing PCI 338 24 80.00 50.00 3.00 0.00 48 10.00 20.00 72 80.00 50.00

The results show that in both resins the presence of V ₂ O ₅ and cysteine is highly favorable for the ability to protect against corrosion. The coatings obtained according to the present invention are intended to be applied directly to uncoated metal substrates without the need for any phosphate or other pretreatment other than cleaning. Such formulations can be applied in any quantity to obtain the desired coating mass required in a particular situation, but they are preferably applied in an amount of 150 to 400 milligrams per square meter. ft (150 to 400 milligrams per 929.03 square centimeters), more preferably in an amount of 175 to 300 milligrams per square meter. ft (from 175 to 300 milligrams per 929.03 square centimeters), and even more preferably in an amount of 175 to 250 milligrams per square meter. ft (from 175 to 250 milligrams per 929.03 square centimeters). The coatings of the present invention are in situ dried (by known methods) conversion coatings, preferably dried by heating to a peak metal temperature (PMT) of 180 to 350 ° F (82 to 177 ° C), more preferably 110 to 350 ° F (43 to 177 ° C), and even more preferably up to an MRI of 200 to 325 ° F (93 to 163 ° C).

Another series of coating formulations was obtained in order to demonstrate the need to introduce elements from both group IVB and group VB. Initially, in the manner described below, resin 3340-082 was prepared using the components listed in table 18 below.

Table 18 Part Material Content, g BUT Deionized water 245.3 Rhodapon L22 1.7 B1 Deionized water 76.1 Rhodapon L22 1.7 Tergital 15-S-20 11.9 IN 2 n-butyl methacrylate 28.6 Styrene 34.1 Methyl methacrylate 62.9 2-ethylhexyl acrylate 46.2 Acetoacetoxyethyl methacrylate 45.3 Polysurf HP 11.3 FROM Ammonium persulfate 0.60 Deionized water 11,4 D 70% t-butyl hydroperoxide 0.31 Deionized water 9.7 E Vitamin C 0.17 Deionized water 9.8 F 0.5% aqueous iron (II) sulfate heptahydrate 1.8 G 28.8% Ammonium hydroxide 4.3 Deionized water 10.5 N Deionized water 14,4

Part A is placed in a four-necked 3-liter flask equipped with a stirrer, condenser, thermocouple and nitrogen inlet. The contents of the flask are heated to 80 ° C and maintained at this temperature in a nitrogen atmosphere. Parts B1 and B2 are mixed separately to obtain uniform transparent formulations. Parts B1 and B2 are mixed together to obtain pre-emulsion B. 5% of pre-emulsion B and 25% of part C are loaded into a flask, the temperature of which is maintained at 80 ° C. After 40 minutes, the remainder of pre-emulsion B and part C are added at a constant speed to the flask for 3 hours, after which part H is used to flush the pump to supply the pre-emulsion to the flask. The contents of the flask are cooled to 70 ° C, while part F is added to the flask. Parts D and E are added to the flask for 30 minutes, after which the temperature of the mixture is maintained at 70 ° C for one hour. Then the mixture is cooled to 40 ° C, while adding part G. The solids content in the obtained latex is 37.2%, pH-6.9, and the particle size is 123 nanometers. The resin is then given the function of dihydropyridine to obtain resin 3340-83 by combining 300 parts by weight of resin 3340-082 with 0.79 parts by weight of propionaldehyde. The mixture is loaded into an airtight container and placed in an oven at 40 ° C for 24 hours, resulting in a resin 3340-083. As described below in table 19, receive a number of compositions for coatings. Composition for coating 164Q is the only one obtained according to the present invention, characterized in that it includes elements from groups IVB and VB. Compositions for coatings 164R and 164S, respectively, do not contain elements of group IVB or VB. Each coating composition is then applied to an HDG panel or Galvalume (Gal) panel with a coating density of approximately 200 milligrams per square meter. ft (200 milligrams per 929.03 square centimeters), after which it is dried to a peak metal temperature of 93 ° C. Then, several panels under all conditions are subjected to the above test with NSS; the obtained average results for several panels at each point in time and conditions are described below in table 20.

Table 19 Component 164Q 164R 164S Di water 62.85 83.95 63.35 Bacote 20 24.0 0,0 24.0 (NH ₄ ) ₂ CO ₃ 0,0 2.9 0,0 V ₂ O ₅ 0.5 0.5 0,0 Resin 3340-083 12.15 12.15 12.15 Cysteine 0.5 0.5 0.5

Table 20 Time, hours (NSS) 164Q Gal 164R Gal 164S Gal 164Q HDG 164R HDG 164S
HDG 24 0 11.0 3.0 0,0 33.3 1,0 48 0 15.3 4.3 0,0 69.0 3.0 72 0 50,0 12.0 0,0 83.3 3.0 96 0,0 3.0 168 1,0 25.0 0.3 4.3 336 9.0 3.0 50,0 504 10.0 10.0 672 12.0 43.3 840 12.0 83.3

The results shown in table 20 clearly show the advantages of using a combination of elements IVB and VB. If there is only one element, the coating composition has minimal corrosion protection.

In another embodiment, the coating compositions obtained according to the present invention include an inorganic part containing a source of at least one of the transition metals of Group IVB of the Periodic Table, namely zirconium, titanium and hafnium, and either at least one element Group VB of the Periodic Table, or a source of chromium. Coating compositions further include an organic polymer. In this embodiment, the coating composition preferably comprises from 9% to 73% by weight. element of group IVB calculated on the total weight of the solids of the coating. A preferred element of group IVB is zirconium, preferably added as zirconium ammonium carbonate. In this embodiment, the coating composition also contains either a chromium source, such as chromium trioxide, or an element of group VB, such as vanadium, niobium or tantalum. The coating composition of this embodiment is also an in situ dried conversion coating. Such a coating also includes at least one of a wide variety of resin-based organic polymers that can be added directly to the coating composition, thereby reducing multi-stage coating processes. The percentage by weight of active solids of the organic polymer, based on the total dry solids of the coating, is preferably from 1% to 75%, more preferably from 25% to 73%, and even more preferably from 40% to 70%. Applicable resin-based organic polymers can be of a wide variety of types, including, by way of example only: epoxy resins, polyvinyl dichlorides, acrylic resins, methacrylate resins, styrene resins, polyurethane dispersions, and polyurethane dispersion hybrids. Examples of such resin-based polymers include Carboset® CR760, Hauthane HD-2120, Hauthane L-2989, Maincote ^TM PR-15, Maincote ^TM PR-71, Avanse MV-100, Rhoplex AC 337N and Alberdingk-Boley LV-51136 and M -2959. Such a coating also allows the addition of reducing agents, such as cysteine, Sn ²⁺ , ascorbic acid or thiojuccinic acid and their oxidation products. The coating composition may also optionally include processing aids, such as various types of waxes, which contribute to the formability of the coated substrates. The introduction of such optional agents has been discussed above. Being a conversion coating, as the term is understood in the art, the components in the coating composition interact with the metal substrate during the coating process to produce a final, in situ dried coating.

The coating compositions obtained according to the present invention, allow to obtain dried in place coating having a unique morphology. The resulting morphology of the in situ dried coating has two phases: unexpectedly, the inorganic part of the coating composition is a continuous phase, while the discontinuous phase comprises an organic polymer. This is an unexpected difference from traditional coatings. A number of chromium-based coating compositions prepared according to the present invention and a number of comparative coating compositions are prepared in accordance with the formulas given in Table 21. The coating compositions are prepared by combining the components together in the order indicated for mixing. All formulations are aged for 24 hours after mixing before being used in the tests described below. In these examples, Bacote® 20 serves as a source for a member of the VB group. The percentage by weight of active solids of the organic polymer, based on the total dry solids of the coating, is preferably from 1% to 75%, more preferably from 25% to 73%, and even more preferably from 40% to 70%. Applicable organic polymers have been described in the previous examples. The organic polymers in all formulations in this example are Carboset® CR760 styrene-acrylic copolymer latex. The latex particle size is determined using laser light scattering measured by Zetasizer 3000HSA manufactured by Malvern Instruments. The average particle size is 111 nanometers, and the range is from 62 to 116 nanometers. The chromium content calculated on the active solids of the coating of compositions 21A and 21B is the same as the chromium content of compositions 21C and 21D. In compositions 21B and 21D of comparative examples, Bacote® 20 is not used, however, the calculated ammonium content of Bacote® 20 is obtained using ammonia. Compositions 21A and 21B have a bright yellow color corresponding to the characteristic color of hexavalent chromium. Compounds 21C and 21D, including a reducing agent such as ascorbic acid, on the contrary, have a green-brown color corresponding to the characteristic color of the composition, mainly containing trivalent chromium. The weight percentage of active solids of the latex-based polymer in Example 21A is 44% based on the total weight of the solids of the coating, while it is 41% in Example 21C. The weight percentage of an element of group IVB, calculated on the total weight of the dry solids of the coating, is 37.00% in Example 21A and 34.50% in Example 21C.

Table 21 Component 21A 21B 21C 21D Deionized water 65.45 73.85 64.70 74.10 Bacote® 20 24.00 0.00 24.00 0.00 Ammonia (29% NH ₃ ) 0.00 4.15 0.00 4.15 Chromium trioxide 0.55 0.55 0.55 0.55 Carboset® CR760 10.00 21.45 10.00 19.70 Vitamin C 0.00 0.00 0.75 1,50 Total 100.00 100.00 100.00 100.00 The total percentage of active solids 9.60 9.60 10.30 10.30

Another series of coatings is prepared using another polymer based on acrylic latex Avanse® MV100 from Rohm and Haas as an organic polymer. Again, the compositions are prepared by mixing the components in the order shown in table 22, and then each composition is aged for 24 hours before use.

The organic polymers in all formulations in this example are Avanse® MV100 latex. The latex particle size is determined using laser light scattering measured by Zetasizer 3000HSA manufactured by Malvern Instruments. The average particle size is 137 nanometers, and the range is from 90 to 207 nanometers. The chromium content calculated on the active solids of the coating of formulations 22A and 22B is the same as the chromium content of formulations 22C and 22D. In compositions 22B and 22D of comparative examples, Bacote® 20 is not used, however, the calculated ammonium content of Bacote® 20 is obtained using ammonia. Compositions 22A and 22B have a bright yellow color corresponding to the characteristic color of hexavalent chromium. Compounds 22C and 22D, including a reducing agent such as ascorbic acid, on the contrary, have a green-brown color corresponding to the characteristic color of the composition, mainly containing trivalent chromium. Example 22E illustrates a chromium-free coating prepared according to the present invention. This example illustrates an embodiment according to which the inorganic part comprises at least one element from group IVB of the periodic table and at least one element from group VB of the periodic table. As an organic polymer, it includes Avanse® MV100. The percentage by weight of active solids of the latex-based polymer in Example 22A is 67% based on the total dry solids of the coating, while it is 65% in Example 22C and 65.9% in Example 22E. The weight percentage of the element of group IVB calculated on the total weight of the dry solids of the coating in example 22A is 21.40%, in example 22C - 20.50%, and in example 22E - 20.80%.

Table 22 Component 22A 22V 22C 22D 22E Deionized water 45.05 57.20 44,20 56.70 44.50 Bacote® 20 28.15 0.00 28.15 0.00 28.15 Ammonia (29% NH ₃ ) 0.00 4.85 0.00 4.85 0.00 Chromium trioxide 0.65 0.65 0.65 0.65 0.00 V ₂ O ₅ 0.00 0.00 0.00 0.00 0.60 Avanse® MV 100 26.15 37.30 26.15 36.60 26.15 Vitamin C 0.00 0.00 0.85 1.20 0.60 Total 100.00 100.00 100.0 100.00 100.00 The total percentage of active solids 19.50 19.50 20.30 20.30 20.00

In comparative example 23, an organic coating solution based on commercial hexavalent chromium P3000B manufactured by Henkel Corporation was used.

In example 24, the composition 21A for coatings is applied to a cleaned aluminum panel with a wire pull rod and dried to a PMT of 93 ° C to obtain a coating whose dry weight is 150 ± 25 milligrams / sq. foot. A thin layer of gold and a thin layer of platinum are then applied to the coated metal in order to facilitate cross-section. After this, a cross section is made using a focused ion beam to obtain a very thin layer of a cross section of the coated substrate. Then, the obtained cross-section is examined using scanning transmission electron microscopy on a dark background. A new morphology of the coating composition obtained according to the present invention is shown in the image obtained by this method, illustrated in figures 1A and 1B. According to this method, the relative brightness compared with the dark areas in the image shows the average atomic number (Z) of the components of the composition. Light areas indicate the presence of components with a higher average Z, while darker areas are indicative of components with a lower average Z. In order to determine the elemental composition in these areas, an X-ray analysis is performed based on the energy dispersion method. The analysis shows that the continuous phase is an inorganic phase, including chromium, zirconium and oxygen. This method involves scanning through a thin layer of a dry coating containing both continuous and dispersed phases of the material, the average Z of which varies significantly. As a result, the image is obtained in 3-dimensional form, revealing a new morphology of the present invention. After drying the coating of Example 21A, residues of zirconium ammonium carbonate, Bacote® 20, produce bright spots. The acrylic latex polymer, which is mainly based on carbon and oxygen, is represented by darker areas. Polymer balls superimposed at various depths in this layer lead to the appearance of the darkest parts of the image. As the obtained image shows, the present invention allows to obtain a coating with a continuous inorganic matrix, inside of which discrete dispersed polymer balls are located. The size of the discrete polymer balls in the image corresponds to the measurement results of the particles of acrylic latex from example 21. The elongation of the polymer balls is explained by the action of shrinkage during drying of the composite structure. In Figure 1A, the platinum / gold topcoat is indicated by the number 10, the coating composition 21A is indicated by the number 20, the dispersed polymer balls are indicated by the number 22, and the continuous inorganic phase is indicated by the number 24. The substrate aluminum is indicated by the number 30. Figure 1B represents a stronger increase in the portion of figure 1A clearly showing the continuous inorganic phase 24 and the dispersed polymer beads 22. Obviously, contrary to expectations, in accordance with the present invention, the polymer latex does not stick together, but remains in the form ispergirovannoy phase in the continuous inorganic phase.

In Example 25, composition 22E, a chromium-free coating composition according to the present invention, is applied to a cleaned Galvalume® panel with a wire pull rod and dried to a PMT of 93 ° C. to obtain a coating whose dry weight is 200 ± 25 milligrams / sq. foot. A transverse section of the metal with the coating focused by the ion beam is carried out, obtaining a thin layer, which is examined using scanning transmission electron microscopy on a dark background as described in Example 24. A new characteristic morphology of the coating composition of the present invention is revealed, the continuous inorganic phase is mainly with a discrete dispersed polymer phase. In order to determine the elemental composition of the continuous and dispersed phases, an X-ray analysis is performed based on the energy dispersion method. Again, the continuous phase is inorganic and includes zirconium, vanadium and oxygen. The size of the observed polymer beads in the coating 22E corresponds to the measurement results of the latex particles used in the composition of example 22E. As for example 24, there is a higher density of polymer spheres in the coating, which corresponds to the difference in acrylic content in the compositions of example 21A and example 22E. The results are shown in figures 2A and 2B, representing a stronger increase in the area shown in figure 2A. The platinum / gold top layer is indicated by the number 60, the coating composition 50 includes polymer beads 54 and a continuous inorganic phase 52, and the substrate is indicated by the number 40.

In example 26, comparative composition 23 is applied to a cleaned aluminum panel with a wire pull rod and dried to a PMT of 93 ° C. to obtain a coating whose dry weight is 150 ± 25 milligrams / sq. foot. A cross section of the metal with the coating focused by the ion beam is carried out, obtaining a thin layer, which is examined using scanning transmission electron microscopy on a dark background as described in Example 24. The image obtained in this way shows that the new morphology of the coatings obtained according to the present the invention is not in the commercial composition for coatings based on chromium. A film is observed comprising a continuous organic phase formed from an adhered polymer characteristic of traditional polymer coatings. In order to determine the elemental composition of the continuous phase, an X-ray analysis is performed based on the energy dispersion method. In figure 3, the substrate is indicated by the number 80, the adhered polymer is indicated by the number 90, and the platinum / gold top layer is indicated by the number 100.

As mentioned above, one of the disadvantages of the described compositions for coatings based on chromium is manifested in the tendency of chromium to leach out of the composition for coatings after its application to the substrate. Therefore, the leaching in the examples illustrating the present invention is compared with the leaching of the comparative samples in example 27. In example 27, each of the chromium-containing coating compositions of examples 21 and 22 is applied to clean, hot-dip galvanized (HDG) steel panels and Galvalume® wire traction rod and dried to a PMT equal to 93 ° C. The dry weight of coatings on HDG panels is 175 ± 25 milligrams / sq. foot. The dry weight of the coatings on Galvalume® panels is 150 ± 25 milligrams / sq. foot. After coating, the panels are tested according to the protocol in order to determine the tendency of each of them to leach chromium under the influence of water. The panels are immersed in 1.5 liters of warm deionized water for 30 seconds, after which they are washed for 30 seconds with cold water and dried. The chromium content of the coated panels is determined before and after testing according to the protocol using a Portspec Model 2501 X-ray Spectrograph manufactured by Cianflone Scientific Instruments Corporation. The difference in chromium content after immersion is determined according to the protocol. The percentage loss of chromium is estimated in numbers from 0 to 5 as follows: 0 = <5%; 1 = 5% to 19.99%; 2 = from 20.00% to 39.99%; 3 = from 40.00% to 59.99%; 4 = from 60.00% to 79.99%; and 5 = from 80% to 100.00%. The results are shown below in table 28. These results show several significant trends. Firstly, none of the coatings obtained according to the present invention, did not significantly leach from any substrate. Secondly, in almost all comparative examples, leaching from all substrates occurred. Thirdly, mainly in comparative examples using trivalent chromium, a significantly higher level of leaching is observed than mainly in comparative examples using hexavalent compounds. And finally, the effectiveness of all comparative compositions is higher on HDG substrates than on Galvalume® substrates.

Table 28 The composition of the example Galvalume® HDG 21A 0 0 21B one 0 21C 0 0 21D 5 four 22A 0 0 22B 2 one 22C 0 0 22D four 2

In Example 29, formulations 21A, 21C and the comparative commercial composition of Example 23 are applied onto clean, hot-dip galvanized steel and Galvalume® panels with a wire pull rod and dried to a PMT of 93 ° C. The dry weight of coatings on HDG panels is 200 ± 25 milligrams / sq. ft, and on Galvalume® panels, 150 ± 25 milligrams / sq. foot. Then 3 additional coated panels from each composition are subjected to a neutral salt spray test according to ASTM-B117-07A and inspected at regular intervals. After each period of time, corrosion is evaluated as a percentage of surface rust. After the first 168 hours of exposure to the sprayed salt, the assessment is done every 24 hours, after which the assessment is carried out at intervals of 168 hours. Record the exposure time in hours for each of the three additional panels at which the percentage of surface rust reaches or falls outside the range of 10% and 25%. The average exposure time at which the specified limits are reached or exceeded is shown in Table 29 below. The results clearly show that the coating compositions prepared according to the present invention are significantly better than the tested commercial chromium-based coating composition. In addition, the effectiveness of all formulations is higher on Galvalume® substrates than on HDG substrates.

Table 29 Composition for coatings Substrate Hours before reaching or exceeding 10% surface rust Hours before reaching or exceeding 25% surface rust 21A Galvalume® 3584 3564 21C Galvalume® 2912 3360 Reference Example 23 Galvalume® 2352 2576 21A HDG 1568 1848 21C HDG 1344 1680 Reference Example 23 HDG 672 784

In example 30, the coating compositions of example 22 are compared with the coating composition of comparative example 23. The coating compositions of examples 22A, 22C and comparative example 23 are applied to clean, hot-dip galvanized steel panels and Galvalume® with a wire rod and dried to RMT equal to 93 ° C. The dry weight of the coatings is 200 ± 25 milligrams / sq. foot on HDG panels and 150 ± 25 milligrams / sq. foot on Galvalume® panels. Then, neutral salt is sprayed onto 3 additional coated panels from each composition and examined at intervals of 168 hours throughout the test period, with the exception of two intervals of 192 hours and 144 hours. After each interval, corrosion is evaluated as a percentage of surface rust. Record the exposure time in hours for each of the three additional panels at which the percentage of surface rust reaches or exceeds a limit of 3%. The average exposure times are shown in Table 30 below. Again, the coating compositions of the present invention are superior to the coating composition of the comparative example, and the effectiveness of all the compositions of the present invention is higher on Galvalume® substrates than on HDG substrates.

Table 30 Composition for coatings Substrate Hours before reaching or exceeding 3% surface rust 22A Galvalume® 1512 22V Galvalume® 1080 Reference Example 23 Galvalume® 1296 22A HDG 848 22C HDG 840 Reference Example 23 HDG 504

The present invention has been described in accordance with relevant legal standards, therefore, this description is illustrative and not limiting in nature. Variants and modifications of the described embodiment are obvious to those skilled in the art and are within the scope of the present invention. Accordingly, the scope of legal protection provided by the present invention is determined only by the following claims.

Claims (23)

1. An in situ dried, anti-corrosion coating applied to a metal substrate, which has a morphology comprising a continuous inorganic phase containing from 9 to 73 wt.% Based on the total weight of the dry solids of the coating of at least one element of the group IVB of the Periodic Table, and a discrete phase containing from 1 to 75 wt.% Calculated on the total weight of dry solids coating the active solids of an organic polymer dispersed in a continuous inorganic phase. 2. The coating according to claim 1, in which the element of group IVB is titanium, zirconium, hafnium, or a mixture thereof. 3. The coating according to claim 1, in which the weight percentage of active solids of the organic polymer, based on the total weight of dry solids of the coating, is from 25 to 73 wt.%. 4. The coating according to claim 1, in which the weight percentage of active solids of the organic polymer, based on the total weight of dry solids of the coating, is from 40 to 70 wt.%. 5. The coating according to claim 1, wherein said organic polymer is selected from the group consisting of epoxy resin, polyvinyl dichloride resin, acrylic resin, methacrylate resin, styrene resin, polyurethane and mixtures thereof. 6. The coating according to claim 1, in which said continuous inorganic phase further comprises at least one element of group VB of the Periodic table. 7. The coating according to claim 6, further comprising a reducing agent or a product of its interaction. 8. The coating according to claim 7, in which said reducing agent includes cysteine, ascorbic acid, Sn ²⁺ , thiocyanate acid, or a mixture thereof. 9. The coating according to claim 6, in which said at least one element of group VB of the Periodic table is vanadium. 10. An in-place dried, anti-corrosion coating on a metal substrate coating that has a morphology comprising a continuous inorganic phase containing from 9 to 73 wt.% Based on the total weight of the dry solids of the coating of at least one element of the group The IVB of the Periodic Table and a chromium source and a discrete phase containing from 1 to 73 wt.% Calculated on the total weight of dry solids coating the active solids of the organic polymer dispersed in a continuous inorganic phase. 11. The coating of claim 10, in which the element of group IVB is titanium, zirconium, hafnium, or a mixture thereof. 12. The coating of claim 10, in which the weight percent of active solids of the organic polymer, based on the total weight of dry solids of the coating, is from 25 to 73 wt.%. 13. The coating of claim 10, in which the weight percent of active solids of the organic polymer, based on the total weight of dry solids of the coating, is from 40 to 70 wt.%. 14. The coating of claim 10, further comprising a reducing agent or a product of its interaction. 15. The coating of claim 14, wherein said reducing agent comprises cysteine, ascorbic acid, Sn ²⁺ , thiocyanate acid, or a mixture thereof. 16. The coating of claim 10, wherein said organic polymer is selected from the group consisting of epoxy resin, polyvinyl dichloride resin, acrylic resin, methacrylate resin, styrene resin, polyurethane, and mixtures thereof. 17. A corrosion-resistant coating conversion composition for metal substrates, comprising an inorganic part containing from 9 to 73 wt.% Based on the total weight of the dry solids of the coating of at least one element of group IVB of the Periodic table and a chromium source and an organic part containing from 1 to 75 wt.% calculated on the total weight of dry solids coating the active solids of the organic polymer, and having a pH of from about 6 to 11. 18. The coating composition according to 17, in which the element of group IVB is titanium, zirconium, hafnium, or a mixture thereof. 19. The coating composition of claim 17, wherein the weight percent of active solids of the organic polymer, based on the total weight of the dry solids of the coating, is from 25 to 73% by weight. 20. The coating composition of claim 17, wherein the weight percent of active solids of the organic polymer, based on the total weight of the dry solids of the coating, is from 40 to 70% by weight. 21. The coating composition of claim 17, further comprising a reducing agent or a product of its interaction. 22. The coating composition of claim 21, wherein said reducing agent comprises cysteine, ascorbic acid, Sn ²⁺ , thiocyanate acid, or a mixture thereof. 23. The coating composition of claim 17, wherein said organic polymer is selected from the group consisting of epoxy resin, polyvinyl dichloride resin, acrylic resin, methacrylate resin, styrene resin, polyurethane, and mixtures thereof.

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