CA2269455A1 - Phosphate conversion coating composition and process - Google Patents
Phosphate conversion coating composition and process Download PDFInfo
- Publication number
- CA2269455A1 CA2269455A1 CA002269455A CA2269455A CA2269455A1 CA 2269455 A1 CA2269455 A1 CA 2269455A1 CA 002269455 A CA002269455 A CA 002269455A CA 2269455 A CA2269455 A CA 2269455A CA 2269455 A1 CA2269455 A1 CA 2269455A1
- Authority
- CA
- Canada
- Prior art keywords
- component
- amount
- range
- ratio
- water soluble
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/34—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides
- C23C22/36—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides containing also phosphates
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/34—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides
- C23C22/36—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides containing also phosphates
- C23C22/361—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing fluorides or complex fluorides containing also phosphates containing titanium, zirconium or hafnium compounds
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/40—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing molybdates, tungstates or vanadates
- C23C22/44—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing molybdates, tungstates or vanadates containing also fluorides or complex fluorides
Abstract
An aqueous liquid combination of simple and complex fluorides, citric acid and/or its salts, phosphate ions, a hydroxylamine source, and an oxidizing agent selected from among water soluble nitroaromatic organic compounds, molybdates, and tungstates, provides good quality protective phosphate conversion coatings on ferrous, zinciferous, aluminous, and magnesium and magnesium alloy metal surfaces, without needing any divalent or higher valent metal cations such as are generally used to produce high quality phosphate conversion coatings. These combinations that contain citric acid produce less sludge than otherwise similar combinations in which gluconic acid is used instead of citric acid. If the combination includes suitable surfactants, no prior chemical cleaning of the metal to be treated is required for good results.
Description
Description PHOSPHATE CONVERSION COATING COMPOSITION AND PROCESS
BACKGROUND OF THE INVENTION
Field of the Invention This invention relates to a composition and process for forming a phosphate con-version coating on active metal surfaces in order to increase the corrosion resistance of s the surfaces, either as treated or after subsequent conventional overcoating of the con-version coating layer formed by an organic based protective coating such as a paint or lacquer. Unlike many of the other compositions known for this general purpose, a com-position according to this invention is well adapted to treating any of a variety of base metals, including at least steel and galvanized steel, zinc and zinc based alloys, aium-,o inum and aluminum based alloys, and magnesium and magnesium based alloys.
The composition and method of the invention are therefore especially well adapted to treating objects having surfaces including more than one typE: of active metal to be protected against corrosion.
Statement of Related Art ~s This invention is an improvement of the invention described and claimed in U.S.
Patent 5,143,562 of Sep. 1, 1992 to Boulos.
DESCRIPTION OF THE INVENTION
Obiect of the Invention The major object of this invention is to achieve equally satisfactory phosphating zo quality as in U. S. Patent 5,143,562 with reduced amounts of sludge compared to the ex-amples in that patent.
General Principles of Description Except in the claims and the operating examples, or where otherwise expressly indicated, all numerical quantities in this description indicating amounts of material or zs conditions of reaction and/or use are to be understood as modified by the word "about"
in describing the broadest scope of the invention. Practice within the numerical limits stated is generally preferred, however. Also, throughout the specification, unless ex-pressly stated io the contrary: percent, "parts of', and ratio values are by weight; the de-scription of a group or class of materials as suitable or preferred for a given purpose in connection with the invention implies that mixtures of any two or more of the members of the group or class are equally suitable or preferred; description of constituents in chemical terms refers to the constituents at the time of addition to any combination speci-fied in the description, and does not necessarily preclude chemical interactions among the constituents of a mixture once mixed; specification of materials in ionic form implies the presence of sufficient counterions to produce electrical neutrality for the composition as a whole; any counterions thus implicitly specified should preferably be selected from among other constituents explicitly specified in ionic form, to the extent possible; other-wise such counterions may be freely selected, except for avoiding counterions that act s adversely to the objects) of the invention; the terms "molecule" and "mole"
(which herein means "gram mole") and their grammatical variations may be applied to ionic, elemental, or any other type of chemical entities defined by the number of atoms of each type pres-ent therein, as well as to substances with well-defined neutral molecules; the first definition of an acronym or other abbreviation applies to all subsequent uses herein of the same abbreviation and applies mutatis mutandis to normal grammatical variations of the initially defined abbreviation; the term "paint" includes all like materials that may be designated by more specialized terms such as lacquer, enamel, varnish, shellac, and the like; and the term "polymer' includes "oligomer", "homopolymer", "copolymer", "terpoly-mer", and the like.
~s Summary of the invention A composition according to this invention is an aqueous liquid composition com-prising, or preferably consisting essentially of, still more preferably consisting of, water and:
(A) a water soluble component providing in aqueous solution dissolved complex tluor-zo ide ions selected from the group consisting of tluoroborate (BF4 ), fluorohafnate (HfFs ~, fluorosificate (SiFs 2), fluorotitanate (TiFs Z), fluorozirconate (ZrFs 2), and mixtures thereof;
(B) a water soluble component providing in aqueous solution ions selected from the group consisting of fluoride (F-), bifluoride (HFz ), and mixtures thereof;
zs (C) a water soluble iron chelating agent component selected from molecules each of which contains at least two, and preferably at feast three, moieties selected from the group consisting of -COOH, -OH, and mixtures thereof;
(D) a water soluble component source of dissolved hydroxyiamine in aqueous sofu-tion;
(E) a water soluble source of dissolved phosphate ions; and (F) a water soluble component providing in aqueous solution dissolved oxidizing agents selected from the group consisting of (i) nitroaromatic organic compounds and (ii) water soluble salts of molybdic acids; and, optionally, one or more of the following components:
~s (G) a component including one or more surfactants to promote cleaning of the metal surface to be treated;
BACKGROUND OF THE INVENTION
Field of the Invention This invention relates to a composition and process for forming a phosphate con-version coating on active metal surfaces in order to increase the corrosion resistance of s the surfaces, either as treated or after subsequent conventional overcoating of the con-version coating layer formed by an organic based protective coating such as a paint or lacquer. Unlike many of the other compositions known for this general purpose, a com-position according to this invention is well adapted to treating any of a variety of base metals, including at least steel and galvanized steel, zinc and zinc based alloys, aium-,o inum and aluminum based alloys, and magnesium and magnesium based alloys.
The composition and method of the invention are therefore especially well adapted to treating objects having surfaces including more than one typE: of active metal to be protected against corrosion.
Statement of Related Art ~s This invention is an improvement of the invention described and claimed in U.S.
Patent 5,143,562 of Sep. 1, 1992 to Boulos.
DESCRIPTION OF THE INVENTION
Obiect of the Invention The major object of this invention is to achieve equally satisfactory phosphating zo quality as in U. S. Patent 5,143,562 with reduced amounts of sludge compared to the ex-amples in that patent.
General Principles of Description Except in the claims and the operating examples, or where otherwise expressly indicated, all numerical quantities in this description indicating amounts of material or zs conditions of reaction and/or use are to be understood as modified by the word "about"
in describing the broadest scope of the invention. Practice within the numerical limits stated is generally preferred, however. Also, throughout the specification, unless ex-pressly stated io the contrary: percent, "parts of', and ratio values are by weight; the de-scription of a group or class of materials as suitable or preferred for a given purpose in connection with the invention implies that mixtures of any two or more of the members of the group or class are equally suitable or preferred; description of constituents in chemical terms refers to the constituents at the time of addition to any combination speci-fied in the description, and does not necessarily preclude chemical interactions among the constituents of a mixture once mixed; specification of materials in ionic form implies the presence of sufficient counterions to produce electrical neutrality for the composition as a whole; any counterions thus implicitly specified should preferably be selected from among other constituents explicitly specified in ionic form, to the extent possible; other-wise such counterions may be freely selected, except for avoiding counterions that act s adversely to the objects) of the invention; the terms "molecule" and "mole"
(which herein means "gram mole") and their grammatical variations may be applied to ionic, elemental, or any other type of chemical entities defined by the number of atoms of each type pres-ent therein, as well as to substances with well-defined neutral molecules; the first definition of an acronym or other abbreviation applies to all subsequent uses herein of the same abbreviation and applies mutatis mutandis to normal grammatical variations of the initially defined abbreviation; the term "paint" includes all like materials that may be designated by more specialized terms such as lacquer, enamel, varnish, shellac, and the like; and the term "polymer' includes "oligomer", "homopolymer", "copolymer", "terpoly-mer", and the like.
~s Summary of the invention A composition according to this invention is an aqueous liquid composition com-prising, or preferably consisting essentially of, still more preferably consisting of, water and:
(A) a water soluble component providing in aqueous solution dissolved complex tluor-zo ide ions selected from the group consisting of tluoroborate (BF4 ), fluorohafnate (HfFs ~, fluorosificate (SiFs 2), fluorotitanate (TiFs Z), fluorozirconate (ZrFs 2), and mixtures thereof;
(B) a water soluble component providing in aqueous solution ions selected from the group consisting of fluoride (F-), bifluoride (HFz ), and mixtures thereof;
zs (C) a water soluble iron chelating agent component selected from molecules each of which contains at least two, and preferably at feast three, moieties selected from the group consisting of -COOH, -OH, and mixtures thereof;
(D) a water soluble component source of dissolved hydroxyiamine in aqueous sofu-tion;
(E) a water soluble source of dissolved phosphate ions; and (F) a water soluble component providing in aqueous solution dissolved oxidizing agents selected from the group consisting of (i) nitroaromatic organic compounds and (ii) water soluble salts of molybdic acids; and, optionally, one or more of the following components:
~s (G) a component including one or more surfactants to promote cleaning of the metal surface to be treated;
(H) a hydrotrope component to increase the solubility of the constituents of compon-ent (G); and (J) a component of antifoam agent or agents, wherein, in said aqueous liquid composition:
s - the ratio by weight of component (A) to component (B) is in the range from 0.3:1.0 to 1.6:1.0;
- the ratio of parts per thousand by weight (hereinafter usually abbreviated as "ppt") of the stoichiometric equivalent as fluoride ions of component (B) to ppt of the stoichiometric equivalent as citric acid of component (C) is in the range from ~0 0.30:1.0 to 8.0:1.0;
- the ratio of ppt of component (C) to ppt of component (D) is in the range from 0.010:1.0 to 6.0:1.0;
- the ratio by weight of component (D) to component (E) is in the range from 0.05:1.0 to 5.0:1.0; and ,s - the ratio of the concentration in ppt of component (E) to the concentration in gram-moles per kilogram (hereinafter usually abbreviated as "M') of component (F) is in the range from 2000:1.0 to 20,000:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in the range from 400:1.0 to 4000:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, Zo water soluble salts thereof, or mixtures thereof, wherein the improvement comprises selecting component (C) from citric acid and its water soluble salts:
A process according to this invention comprises at a minimum a step of contact-ing a metal surface to be treated with a composition according to the invention for a suffi-Zs dent time to form on the metal surface a detectable conversion coating. The composi-tions according to this invention, when they contain adequate amounts and types of sur-factant component (G) as is usually preferred, are especially well suited to treating metal surfaces that have not been subjected 1o any prior chemical cleaning or conventional "activation" (e.g., contact with a suitably prepared aqueous dispersion of colloidal titanium compounds), but conventional metal surface cleaning andlor activation steps before contact between the metal to be treated and the compositions according to the invention may be used if desired as part of a process according to this invention.
A process according to the invention also may, and usually preferably does, in clude conventional steps subsequent to the contact between the metal surface to be ~s treated and the compositions according to the invention. These subsequent steps, e.g., may inGude rinsing with water, using reactive post treatments, such as with compositions WO 98/20186 PCT/US97/19313 _ according to the teachings of U. S. Patent 4,963,596 or with chromate containing so-lutions, and painting or otherwise protecting the surface with an outer coating of an or-ganic based solid material.
Description of Preferred Embodiments of the Invention s With increasing preference in the order given and with independent preference for each noted component, compositions according to the invention contain no more than 4, 0.9, 0.5, 0.2, 0.07, or 0.01 grams per liter (hereinafter "g/l_") of cottons selected from the group consisting of Zn'2, Ni'z, Mn'Z, Co'Z, Cu'Z, Fe'2, Ca'2, Mg'2, and all metal cottons with a valence of 3 or higher.
Prefer-ed sources for component (A) as described above are the acids and the alkali metal and ammonium salts having the anions noted. In a composition ready for use in a process according to this invention (briefly denoted hereinafter as a "working compo sition"), it is preferred, with increasing preference in the order given, that the concentra tion of component (A), calculated as the anions) present, be in the range from 0.05 to ~s 1.0, 0.10 to 0.70, or 0.30 to 0.50 ppt.
However, for economy in shipment, it is often preferable to prepare a concentrat-ed composition according to the invention that is suitable for dilution with water, optionally with addition of acid or base for pH control at the same time as dilution of the concentrat-ed composition, to prepare, at the point of use, a working composition with a concentra-zo tion of component (A) in the range given above and of other components in the ranges given below. In such a concentrate, the concentrations of all components except water preferably are in the range from 5 to 100, more preferably from 12 to 50, or still more preferably from 20 to 25, times the concentrations of the same components in a working composition.
is For component (B) described above, the most preferred source is hydrofluoric acid, and ammonium and alkali metal fluorides and bitluorides are otherwise preferred among other acceptable sources. In a working composition, it is preferred, with increas ing preference in the order given, that the concentration of component (B), calculated as its stoichiometric equivalent of fluorine atoms, be in the range from 0.1 to 2.0, 0.2 to 0.8, 0 or 0.4 to 0.7 ppt.
For component (C) described above, only citric acid and/or its salts are used.
In a working composition, it is preferred that the total concentration of citric acid and/or its stoichiometric equivalent for any citrate salts present be at least, with increasing prefer-ence in the order given, 0.0010, 0.0015, 0.0025, 0.0050, 0.010, 0.020, 0.030, 0.040, ~s 0.050, 0.060, 0.070, 0.080, 0.090, or 0.097 ppt and independently preferably be not more than, with increasing preference in the order given, 0.45, 0.40, 0.35, 0.30, 0.25, 0.20, 0.17, 0.15, 0.13, or 0.11 ppt of the total composition.
For component (D) the most preferred source is hydroxylamine sulfate (briefly de-noted hereinafter as "HAS"), but many other sources are satisfactory. In a working com-position, it is preferred, with increasing preference in the order given, that the con-centration of component (D), calculated as its stoichiometric equivalent of hydroxylamine s (H2NOH), be in the range from 0.1 to 10, 0.5 to 6, or 0~.5 to 2.0, g/L.
For component (E) the most preferred source is orthophosphoric acid (H3P04) and/or its alkali metal and ammonium salts. The acid itself and all anions produced by its partial or total ionization in aqueous solution are considered part of component (E) as described herein. In a working composition, it is preferred, wish increasing preference in the order given, that the concentration of component (E), calculated as its stoichiometric equivalent as phosphoric acid (H3P04), be in the range: from 3 to 30, 7 to 15, or 5 to 12, g/L.
In one embodiment of the invention, the most preferred sources of component (F) are water soluble salts of one of the molybdic acids, most preferably of HZMoO,. This ,s component provides a dark blue colored conversion coating that is easy to detect visually and gives good corrosion protection, adequate for many purposes. This embodiment is generally preferred by users who do not wish to quantitatively monitor the thickness of the coating produced. In a working composition of this embodiment, it is preferred, with increasing preference in the order given, that the total concentration of (F) be in the so range from 0.00002 to 0.02, 0.0002 to 0.02, or 0.002 to 0.02 M of total molybdate salts.
In another embodiment of the invention, which produces the maximum possible corrosion resistance, paranitrobenzene sulfonic acid andlor its water soluble salts, especially the sodium salt, are the most preferred source of component (F).
The conver-sion coating layer produced by this embodiment is often difficult to detect visually, but the is thickness of the coating can be readily determined by the quantitative methods known to those skilled in the art, which generally involve weighing a sample of the coating before and after using an appropriate stripping solution composition to remove the conversion coating. In a working composition according to this embodiment, it is preferred, with in-creasing preference in the order given, that the concentration of component (F) be in the range from 0.0001 to 0.1, 0.001 to 0.1, or 0.01 to 0.1 M.
In a working composition, it is preferred, with increasing preference in the order given, that the concentration of component (G) be in the range from 0 to 5.0, 1.5 to 3.0, or 1.5 to 2.0, g/L. Preferred chemical types for component (G) are polyethoxylated alco-hols with about 12 - 22 carbon atoms in the alcohol portion, other modified polyethers of ~s the aliphatic or aromatic types, and salts of complex organic phosphate esters.
A hydrotrope is defined generally as a substance that increases the solubility in WO 98/20186 PCT/CTS97/19313 _ water of another material chat is only partially soluble. Hydrotrope component (H) is needed in the compositions according to this invention only if the amount of component (G) desired in the compositions is so large as to exceed the limit of ready solubility in the absence of a hydrotrope. In such cases, adequate solubility to produce an optically clear s and homogeneous composition as preferred can generally be achieved by use of a hydrotrope. A hydrotrope for this invention is preferably an ammonium or alkali metal salt of a sulfonate of toluene, xylene, or cumene, or a mixture of two or more such salts. The most preferred hydrotrope is sodium xylene sulfonate. A water soluble complex organo-phosphate ester or acid ester may often be advantageously added as an auxiliary hy-,o drotrope. In a working composition, it is preferred, with increasing preference in the order given, that the concentration of component (H) be in the range from 0 to 2.0, 0.4 to 1.2, or 0.6 to 0.8, g/L.
Preferred chemical types for component (J) are (i) aliphatic petroleum distillates modified with hydrophobic silica andlor (ii) polyethoxylated alcohols. Block copolymers ,s of ethylene oxide and propylene oxide may also be used. The amount used, if needed, should be sufficient to reduce the foaming of the composition to an acceptable level.
In a working composition, it is preferred, with increasing preference in the order given, that the concentration of free acid be in the range from 0.0 to 2.0, 0.0 to 1.0, or 0.2 to 1.0, "points" and that the concentration of total acid be in the range from 3 to 12, 5 to zo 10, or 6.0 to 9.0, "points". "Points" are defined for this purpose as the number of millilit-ers (hereinafter "ml") of 0.1 N NaOH solution required to titrate a 10 ml sample of the composition, to a phenolphthalein end point for total acid and a bromthymol blue end point for free acid. Independently, it is preferred that the pH value of a working composi-tion according to the invention be in the range from 3.0 to 7.0, 4.2 to 5.9, or 4.5 to 5.5.
zs For concentrated compositions according to the invention, it is more useful to characterize the preferred embodiments in terms of ratios of ingredients rather than specific concentrations as noted above for the working compositions.
Specifically, it is preferred, with increasing preference in the order given for each ratio, that:
- the ratio by weight of component (A) to the stoichiometric equivalent as tluoride ~o ions of component (B) be in the range from 0.3:1.0 to 1.6:1.0, from 0.5:1.0 to 1.3:1.0, or from 0.6:1.0 to 0.9:1.0;
- the ratio of ppt of the stoichiometric equivalent as fluoride ions of component (B) to ppt of the stoichiometr~c equivalent as citric acid of component (C) be at least, with increasing preference in the order given, 0.35:1.0, 0.45:1.0, 0.55:1.0, 3s 0.65:1.0, 0.75:1.0, 0.85:1.0, 0.95:1.0, 1.05:1.0, 1.15:1.0, 1.25:1.0, 1.35:1.0, 1.45:1.0, 1.55:1.0, 1.60:1.0, or 1.65:1.0 and independently preferably be not more than, with increasing preference in the order given, 7.0:1.0, 6.0:1.0, 5.5:1.0, 5.0:1.0, 4.5:1.0, 4.0:1.0, 3.5:1.0, 3.1:1.0, 2.7:1.0, 2.4:1.0, 2.2:1.0, 2.00:1.0, 1.90:1.0, 1.85:1.0, 1.80, or 1.75:1.0;
- the ratio of ppt of the stoichiometric equivalent as citric acid of component (C) to s ppt of component (D) be not less than, with increasing preference in the order given, 0.040:1.0, 0.070:1.0, 0.100:1.0, 0.130:1.0, 0.160:1.0, 0.190:1.0, 0.220:1.0, 0.250:1.0, 0.280:1.0, 0.310:1.0, 0.340:1.0, 0.360:1.0, 0.390:1.0, 0.420:1.0, 0.440:1.0, or 0.460:1.0 and independently preferably be not more than, with in-creasing preference in the order given, 5.0:1.0, 4.5:1.0, 4.0:1.0, 3.5:1.0, 3.0:1.0, ~0 2.5:1.0, 2.0:1.0, 2.0:1.0, 1.5:1.0, 1.0:1.0, 0.80:'1.0, 0.70:1.0, 0.60:1.0, 0.55:1.0, or 0.50:1.0;
- the ratio by weight of component {D) to component (E) be in the range from 1:8 to 1:80, from 1:12 to 1:59, or from 1:21 to 1:40;
the ratio of the concentration in g/L of component (E) to the total concentration ~s in M of nitrobenzene sulfonic acid and its salts, if .at least one of these ingredients is present in the composition, be in the range from 400:1 to 4000:1, from 860:1 to 2565:1, or from 1400:1 to 1800:1 and the ratio of the concentration in g/L
of component (E) to the total concentration in M of molybdate salts, if at least one of these ingredients is present in the composition, be in the range from 2000:1 to zo 20,000:1, from 4300:1 to 12,825:1, or from 70t)0:1 to 9000:1.
In determining these ratios, the components are to be measured in the same manner and units as described above for measuring the concentrations of the same components in working solutions.
In a process according to the invention, contact between the metal surface to be zs treated and a composition according to the invention may be accomplished by spraying, dipping, or any other convenient method or combination of methods. The temperature during contact between the metal treated and the composition according to the invention preferably is, with increasing preference in the order given, in the range from 21 to 85, 25 to 70, or 30 to 65, °C. The time of contact preferably is, with increasing preference 3o in the order given, in the range from 5 sec to 15 minutes (hereinafter "min"), 15 sec to 10 min, or 30 sec to 5 min. The add-on mass of the phosphate coating formed preferably is, with increasing preference in the order given, in the range from 12 to 1600, 98 to 975, or 285 to 700, milligrams per square meter (hereinafter sometimes abbreviated as "mglmz) of surface treated.
Further appreciation of the present invention may be had from considering the fol-lowing examples and comparative examples which are intended to illustrate, but not limit, 6 PCT/LTS97/19313 _ - the invention.
s Examples and Comparison Examples Concentrate compositions were prepared containing the following components Parts Material by Wei4ht 105 50 % sodium hydroxide 154 75 % orthophosphoric acid Variable ion sequestering agent - see table below ,0 35 40 % sodium xylene sulfonate 3.5 ANTAROXT"" LF-330 5.6 TRITONT"" DF-16 17.5 RHODAFACT"" RP-710 10.5 Hydroxylamine sulfate ,s 15.4 p-nitrobenzene sulfonic acid 4.9 70 % hydrofluoric acid 3.5 Sodium fluoroborate The balance to a total of 1000 parts was water.
ANTAROXT"" LF-330 was commercially obtained from Rhone-Poulenc and is re-zo ported by its supplier to be a modified linear aliphatic polyether detergent and wetting agent with low foaming tendency. TRITONT"" DF-16 was commercially obtained from Union Carbide Corp. and is reported by its supplier to be a modified polyethoxylated straight chain alcohol nonionic low foaming detergent. RHODAFACr"" RP-710 was com-mercially obtained from Rhone-Poulenc and is reported by its supplier to be a complex zs organic phosphate anionic detergent and emulsifier with hydrotropic effect on low foam-ing nonionic surfactants.
In preparing these concentrates, the sodium hydroxide was added to about 90 of the amount of water expected to be finally needed; the phosphoric acid was added next, with cooling until the temperature of the mixture fell to 43 °C
or below. Then the ~o sequestering agent, the principal hydrotrope, and the three surfactants were added in rapid succession and the mixture stirred until clear (about 15 min). The hydroxylamine sulfate and p-nitrobenzene sulfonic acid were then added, and 30 minutes of additional mixing was performed. Subsequently, the last two named ingredients were added, fol-lowed by another 30 minutes of mixing. The remaining water was then added, to the ex-35 tent necessary to achieve a total of 1000 parts by weight.
The concentrated compositions as described above were diluted with water to produce a working composition containing 50 grams of the concentrated composition per liter of the working composition. Each working composition had a pH value of 4.8 and a total acidity as shown in Table 1 below.
Cold rolled carbon steel test panels, without any preliminary chemical cleaning, were immersed for 5 minutes each in a five liter volume of the above specified working s compositions at a temperature of 49 °C, rinsed in cold tap water, and dried. A total of 25 rectangular panels, each about 30 x 15 centimeters in size, were used in each composi-tion, with no attempt at replenishment, and coating add-on masses per unit area in grams per square meter (hereinafter usually abbreviated as "glm2) were measured for the first, twelfth, and twenty-fifth panels in each composition. The solid sludge formed in each ,o composition was then collected by filtration, dried, and weighed. The sequestering agent in the concentrated compositions, coating masses, and sludge amounts are shown in Table 1. As can be seen from the results in that Table, large concentrations of citric acid completely suppress sludge formation, but the coating masses achieved fall rather rapidly. Smaller amounts of citric acid give much more stable coating performance, and ,s the amount of sludge is still considerably less than when gluconic acid is used as the se-questering agent.
Property Measured Results for:
Examples: Comparison Ezamples:
1 Z; 1 2 Total Acid 10 10 9 10 Points 0.20 % 0.28 %
Sequestering citric 1_0 % none glu-Agent acid conic acid 1st Panel 0.81 0.59 0.73 0.73 Coating Masses, g~m~ 12th Panel 0.81 0.27 0.68 0.66 25th Panel 0.81 0.:22 0.68 0.68 Dry Sludge 1.6 0.0 3.7 2.9 Mass, grams
s - the ratio by weight of component (A) to component (B) is in the range from 0.3:1.0 to 1.6:1.0;
- the ratio of parts per thousand by weight (hereinafter usually abbreviated as "ppt") of the stoichiometric equivalent as fluoride ions of component (B) to ppt of the stoichiometric equivalent as citric acid of component (C) is in the range from ~0 0.30:1.0 to 8.0:1.0;
- the ratio of ppt of component (C) to ppt of component (D) is in the range from 0.010:1.0 to 6.0:1.0;
- the ratio by weight of component (D) to component (E) is in the range from 0.05:1.0 to 5.0:1.0; and ,s - the ratio of the concentration in ppt of component (E) to the concentration in gram-moles per kilogram (hereinafter usually abbreviated as "M') of component (F) is in the range from 2000:1.0 to 20,000:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in the range from 400:1.0 to 4000:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, Zo water soluble salts thereof, or mixtures thereof, wherein the improvement comprises selecting component (C) from citric acid and its water soluble salts:
A process according to this invention comprises at a minimum a step of contact-ing a metal surface to be treated with a composition according to the invention for a suffi-Zs dent time to form on the metal surface a detectable conversion coating. The composi-tions according to this invention, when they contain adequate amounts and types of sur-factant component (G) as is usually preferred, are especially well suited to treating metal surfaces that have not been subjected 1o any prior chemical cleaning or conventional "activation" (e.g., contact with a suitably prepared aqueous dispersion of colloidal titanium compounds), but conventional metal surface cleaning andlor activation steps before contact between the metal to be treated and the compositions according to the invention may be used if desired as part of a process according to this invention.
A process according to the invention also may, and usually preferably does, in clude conventional steps subsequent to the contact between the metal surface to be ~s treated and the compositions according to the invention. These subsequent steps, e.g., may inGude rinsing with water, using reactive post treatments, such as with compositions WO 98/20186 PCT/US97/19313 _ according to the teachings of U. S. Patent 4,963,596 or with chromate containing so-lutions, and painting or otherwise protecting the surface with an outer coating of an or-ganic based solid material.
Description of Preferred Embodiments of the Invention s With increasing preference in the order given and with independent preference for each noted component, compositions according to the invention contain no more than 4, 0.9, 0.5, 0.2, 0.07, or 0.01 grams per liter (hereinafter "g/l_") of cottons selected from the group consisting of Zn'2, Ni'z, Mn'Z, Co'Z, Cu'Z, Fe'2, Ca'2, Mg'2, and all metal cottons with a valence of 3 or higher.
Prefer-ed sources for component (A) as described above are the acids and the alkali metal and ammonium salts having the anions noted. In a composition ready for use in a process according to this invention (briefly denoted hereinafter as a "working compo sition"), it is preferred, with increasing preference in the order given, that the concentra tion of component (A), calculated as the anions) present, be in the range from 0.05 to ~s 1.0, 0.10 to 0.70, or 0.30 to 0.50 ppt.
However, for economy in shipment, it is often preferable to prepare a concentrat-ed composition according to the invention that is suitable for dilution with water, optionally with addition of acid or base for pH control at the same time as dilution of the concentrat-ed composition, to prepare, at the point of use, a working composition with a concentra-zo tion of component (A) in the range given above and of other components in the ranges given below. In such a concentrate, the concentrations of all components except water preferably are in the range from 5 to 100, more preferably from 12 to 50, or still more preferably from 20 to 25, times the concentrations of the same components in a working composition.
is For component (B) described above, the most preferred source is hydrofluoric acid, and ammonium and alkali metal fluorides and bitluorides are otherwise preferred among other acceptable sources. In a working composition, it is preferred, with increas ing preference in the order given, that the concentration of component (B), calculated as its stoichiometric equivalent of fluorine atoms, be in the range from 0.1 to 2.0, 0.2 to 0.8, 0 or 0.4 to 0.7 ppt.
For component (C) described above, only citric acid and/or its salts are used.
In a working composition, it is preferred that the total concentration of citric acid and/or its stoichiometric equivalent for any citrate salts present be at least, with increasing prefer-ence in the order given, 0.0010, 0.0015, 0.0025, 0.0050, 0.010, 0.020, 0.030, 0.040, ~s 0.050, 0.060, 0.070, 0.080, 0.090, or 0.097 ppt and independently preferably be not more than, with increasing preference in the order given, 0.45, 0.40, 0.35, 0.30, 0.25, 0.20, 0.17, 0.15, 0.13, or 0.11 ppt of the total composition.
For component (D) the most preferred source is hydroxylamine sulfate (briefly de-noted hereinafter as "HAS"), but many other sources are satisfactory. In a working com-position, it is preferred, with increasing preference in the order given, that the con-centration of component (D), calculated as its stoichiometric equivalent of hydroxylamine s (H2NOH), be in the range from 0.1 to 10, 0.5 to 6, or 0~.5 to 2.0, g/L.
For component (E) the most preferred source is orthophosphoric acid (H3P04) and/or its alkali metal and ammonium salts. The acid itself and all anions produced by its partial or total ionization in aqueous solution are considered part of component (E) as described herein. In a working composition, it is preferred, wish increasing preference in the order given, that the concentration of component (E), calculated as its stoichiometric equivalent as phosphoric acid (H3P04), be in the range: from 3 to 30, 7 to 15, or 5 to 12, g/L.
In one embodiment of the invention, the most preferred sources of component (F) are water soluble salts of one of the molybdic acids, most preferably of HZMoO,. This ,s component provides a dark blue colored conversion coating that is easy to detect visually and gives good corrosion protection, adequate for many purposes. This embodiment is generally preferred by users who do not wish to quantitatively monitor the thickness of the coating produced. In a working composition of this embodiment, it is preferred, with increasing preference in the order given, that the total concentration of (F) be in the so range from 0.00002 to 0.02, 0.0002 to 0.02, or 0.002 to 0.02 M of total molybdate salts.
In another embodiment of the invention, which produces the maximum possible corrosion resistance, paranitrobenzene sulfonic acid andlor its water soluble salts, especially the sodium salt, are the most preferred source of component (F).
The conver-sion coating layer produced by this embodiment is often difficult to detect visually, but the is thickness of the coating can be readily determined by the quantitative methods known to those skilled in the art, which generally involve weighing a sample of the coating before and after using an appropriate stripping solution composition to remove the conversion coating. In a working composition according to this embodiment, it is preferred, with in-creasing preference in the order given, that the concentration of component (F) be in the range from 0.0001 to 0.1, 0.001 to 0.1, or 0.01 to 0.1 M.
In a working composition, it is preferred, with increasing preference in the order given, that the concentration of component (G) be in the range from 0 to 5.0, 1.5 to 3.0, or 1.5 to 2.0, g/L. Preferred chemical types for component (G) are polyethoxylated alco-hols with about 12 - 22 carbon atoms in the alcohol portion, other modified polyethers of ~s the aliphatic or aromatic types, and salts of complex organic phosphate esters.
A hydrotrope is defined generally as a substance that increases the solubility in WO 98/20186 PCT/CTS97/19313 _ water of another material chat is only partially soluble. Hydrotrope component (H) is needed in the compositions according to this invention only if the amount of component (G) desired in the compositions is so large as to exceed the limit of ready solubility in the absence of a hydrotrope. In such cases, adequate solubility to produce an optically clear s and homogeneous composition as preferred can generally be achieved by use of a hydrotrope. A hydrotrope for this invention is preferably an ammonium or alkali metal salt of a sulfonate of toluene, xylene, or cumene, or a mixture of two or more such salts. The most preferred hydrotrope is sodium xylene sulfonate. A water soluble complex organo-phosphate ester or acid ester may often be advantageously added as an auxiliary hy-,o drotrope. In a working composition, it is preferred, with increasing preference in the order given, that the concentration of component (H) be in the range from 0 to 2.0, 0.4 to 1.2, or 0.6 to 0.8, g/L.
Preferred chemical types for component (J) are (i) aliphatic petroleum distillates modified with hydrophobic silica andlor (ii) polyethoxylated alcohols. Block copolymers ,s of ethylene oxide and propylene oxide may also be used. The amount used, if needed, should be sufficient to reduce the foaming of the composition to an acceptable level.
In a working composition, it is preferred, with increasing preference in the order given, that the concentration of free acid be in the range from 0.0 to 2.0, 0.0 to 1.0, or 0.2 to 1.0, "points" and that the concentration of total acid be in the range from 3 to 12, 5 to zo 10, or 6.0 to 9.0, "points". "Points" are defined for this purpose as the number of millilit-ers (hereinafter "ml") of 0.1 N NaOH solution required to titrate a 10 ml sample of the composition, to a phenolphthalein end point for total acid and a bromthymol blue end point for free acid. Independently, it is preferred that the pH value of a working composi-tion according to the invention be in the range from 3.0 to 7.0, 4.2 to 5.9, or 4.5 to 5.5.
zs For concentrated compositions according to the invention, it is more useful to characterize the preferred embodiments in terms of ratios of ingredients rather than specific concentrations as noted above for the working compositions.
Specifically, it is preferred, with increasing preference in the order given for each ratio, that:
- the ratio by weight of component (A) to the stoichiometric equivalent as tluoride ~o ions of component (B) be in the range from 0.3:1.0 to 1.6:1.0, from 0.5:1.0 to 1.3:1.0, or from 0.6:1.0 to 0.9:1.0;
- the ratio of ppt of the stoichiometric equivalent as fluoride ions of component (B) to ppt of the stoichiometr~c equivalent as citric acid of component (C) be at least, with increasing preference in the order given, 0.35:1.0, 0.45:1.0, 0.55:1.0, 3s 0.65:1.0, 0.75:1.0, 0.85:1.0, 0.95:1.0, 1.05:1.0, 1.15:1.0, 1.25:1.0, 1.35:1.0, 1.45:1.0, 1.55:1.0, 1.60:1.0, or 1.65:1.0 and independently preferably be not more than, with increasing preference in the order given, 7.0:1.0, 6.0:1.0, 5.5:1.0, 5.0:1.0, 4.5:1.0, 4.0:1.0, 3.5:1.0, 3.1:1.0, 2.7:1.0, 2.4:1.0, 2.2:1.0, 2.00:1.0, 1.90:1.0, 1.85:1.0, 1.80, or 1.75:1.0;
- the ratio of ppt of the stoichiometric equivalent as citric acid of component (C) to s ppt of component (D) be not less than, with increasing preference in the order given, 0.040:1.0, 0.070:1.0, 0.100:1.0, 0.130:1.0, 0.160:1.0, 0.190:1.0, 0.220:1.0, 0.250:1.0, 0.280:1.0, 0.310:1.0, 0.340:1.0, 0.360:1.0, 0.390:1.0, 0.420:1.0, 0.440:1.0, or 0.460:1.0 and independently preferably be not more than, with in-creasing preference in the order given, 5.0:1.0, 4.5:1.0, 4.0:1.0, 3.5:1.0, 3.0:1.0, ~0 2.5:1.0, 2.0:1.0, 2.0:1.0, 1.5:1.0, 1.0:1.0, 0.80:'1.0, 0.70:1.0, 0.60:1.0, 0.55:1.0, or 0.50:1.0;
- the ratio by weight of component {D) to component (E) be in the range from 1:8 to 1:80, from 1:12 to 1:59, or from 1:21 to 1:40;
the ratio of the concentration in g/L of component (E) to the total concentration ~s in M of nitrobenzene sulfonic acid and its salts, if .at least one of these ingredients is present in the composition, be in the range from 400:1 to 4000:1, from 860:1 to 2565:1, or from 1400:1 to 1800:1 and the ratio of the concentration in g/L
of component (E) to the total concentration in M of molybdate salts, if at least one of these ingredients is present in the composition, be in the range from 2000:1 to zo 20,000:1, from 4300:1 to 12,825:1, or from 70t)0:1 to 9000:1.
In determining these ratios, the components are to be measured in the same manner and units as described above for measuring the concentrations of the same components in working solutions.
In a process according to the invention, contact between the metal surface to be zs treated and a composition according to the invention may be accomplished by spraying, dipping, or any other convenient method or combination of methods. The temperature during contact between the metal treated and the composition according to the invention preferably is, with increasing preference in the order given, in the range from 21 to 85, 25 to 70, or 30 to 65, °C. The time of contact preferably is, with increasing preference 3o in the order given, in the range from 5 sec to 15 minutes (hereinafter "min"), 15 sec to 10 min, or 30 sec to 5 min. The add-on mass of the phosphate coating formed preferably is, with increasing preference in the order given, in the range from 12 to 1600, 98 to 975, or 285 to 700, milligrams per square meter (hereinafter sometimes abbreviated as "mglmz) of surface treated.
Further appreciation of the present invention may be had from considering the fol-lowing examples and comparative examples which are intended to illustrate, but not limit, 6 PCT/LTS97/19313 _ - the invention.
s Examples and Comparison Examples Concentrate compositions were prepared containing the following components Parts Material by Wei4ht 105 50 % sodium hydroxide 154 75 % orthophosphoric acid Variable ion sequestering agent - see table below ,0 35 40 % sodium xylene sulfonate 3.5 ANTAROXT"" LF-330 5.6 TRITONT"" DF-16 17.5 RHODAFACT"" RP-710 10.5 Hydroxylamine sulfate ,s 15.4 p-nitrobenzene sulfonic acid 4.9 70 % hydrofluoric acid 3.5 Sodium fluoroborate The balance to a total of 1000 parts was water.
ANTAROXT"" LF-330 was commercially obtained from Rhone-Poulenc and is re-zo ported by its supplier to be a modified linear aliphatic polyether detergent and wetting agent with low foaming tendency. TRITONT"" DF-16 was commercially obtained from Union Carbide Corp. and is reported by its supplier to be a modified polyethoxylated straight chain alcohol nonionic low foaming detergent. RHODAFACr"" RP-710 was com-mercially obtained from Rhone-Poulenc and is reported by its supplier to be a complex zs organic phosphate anionic detergent and emulsifier with hydrotropic effect on low foam-ing nonionic surfactants.
In preparing these concentrates, the sodium hydroxide was added to about 90 of the amount of water expected to be finally needed; the phosphoric acid was added next, with cooling until the temperature of the mixture fell to 43 °C
or below. Then the ~o sequestering agent, the principal hydrotrope, and the three surfactants were added in rapid succession and the mixture stirred until clear (about 15 min). The hydroxylamine sulfate and p-nitrobenzene sulfonic acid were then added, and 30 minutes of additional mixing was performed. Subsequently, the last two named ingredients were added, fol-lowed by another 30 minutes of mixing. The remaining water was then added, to the ex-35 tent necessary to achieve a total of 1000 parts by weight.
The concentrated compositions as described above were diluted with water to produce a working composition containing 50 grams of the concentrated composition per liter of the working composition. Each working composition had a pH value of 4.8 and a total acidity as shown in Table 1 below.
Cold rolled carbon steel test panels, without any preliminary chemical cleaning, were immersed for 5 minutes each in a five liter volume of the above specified working s compositions at a temperature of 49 °C, rinsed in cold tap water, and dried. A total of 25 rectangular panels, each about 30 x 15 centimeters in size, were used in each composi-tion, with no attempt at replenishment, and coating add-on masses per unit area in grams per square meter (hereinafter usually abbreviated as "glm2) were measured for the first, twelfth, and twenty-fifth panels in each composition. The solid sludge formed in each ,o composition was then collected by filtration, dried, and weighed. The sequestering agent in the concentrated compositions, coating masses, and sludge amounts are shown in Table 1. As can be seen from the results in that Table, large concentrations of citric acid completely suppress sludge formation, but the coating masses achieved fall rather rapidly. Smaller amounts of citric acid give much more stable coating performance, and ,s the amount of sludge is still considerably less than when gluconic acid is used as the se-questering agent.
Property Measured Results for:
Examples: Comparison Ezamples:
1 Z; 1 2 Total Acid 10 10 9 10 Points 0.20 % 0.28 %
Sequestering citric 1_0 % none glu-Agent acid conic acid 1st Panel 0.81 0.59 0.73 0.73 Coating Masses, g~m~ 12th Panel 0.81 0.27 0.68 0.66 25th Panel 0.81 0.:22 0.68 0.68 Dry Sludge 1.6 0.0 3.7 2.9 Mass, grams
Claims (20)
1. A liquid aqueous composition of matter, comprising water and:
(A) an amount, measured in grams per kilogram of total composition (hereinafter usually abbreviated as "g/kg"), of a water soluble component providing in aqueous solution dissolved complex fluoride ions selected from the group consisting of fluoroborate (BF4-), fluorohafnate (HfF6-2), fluorosilicate (SiF6-2), fluorotitanate (TiF6-2), fluorozirconate (ZrF6-2), and mixtures thereof;
(B) an amount, measured in grams of its stoichiometric equivalent as fluoride ions per kilogram of total composition, of a water soluble component providing in aqueous solution ions selected from the group consisting of fluoride (F-), bifluoride (HF2-), and mixtures thereof;
(C) an amount, measured in grams of its stoichiometric equivalent as citric acid per kilogram of total composition, of a water soluble iron chelating agent component selected from the group consisting of citric acid, salts of citric acid, and mixtures of any two or more of these;
(D) an amount, measured in grams of its stoichiometric equivalent as hydroxylamine per kilogram of total composition, of a water soluble component source of dissolved hydroxylamine in aqueous solution;
(E) an amount, measured in grams of its stoichiometric equivalent as phosphate ions per kilogram of total composition, of a water soluble source of dissolved phosphate ions; and (F) an amount, measured in moles per kilogram, of a water soluble component providing in aqueous solution dissolved oxidizing agents selected from the group consisting of (i) p-nitrobenzene sulfonic acid, water soluble salts thereof, and mixtures thereof and (ii) water soluble salts of molybdic acids and mixtures thereof;
wherein:
- the amount of component (A) has a ratio to the amount of component (B) that is in a range from about 0.3:1.0 to about 1.6:1.0;
- the amount of component (B) has a ratio to the amount of component (C) that is in a range from about 0.30:1.0 to about 8.0:1.0;
- the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.05:1.0 to about 5.0:1.0;
- the amount of component (D) has a ratio to the amount of component (E) that is in a range from about 0.05:1.0 to about 5.0:1.0; and - the amount of component (E) has a ratio to the amount of component (F) that is in a range from about 2000:1.0 to about 20,000:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in a range from about 400:1.0 to about 4000:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, water soluble salts thereof, or mixtures thereof.
(A) an amount, measured in grams per kilogram of total composition (hereinafter usually abbreviated as "g/kg"), of a water soluble component providing in aqueous solution dissolved complex fluoride ions selected from the group consisting of fluoroborate (BF4-), fluorohafnate (HfF6-2), fluorosilicate (SiF6-2), fluorotitanate (TiF6-2), fluorozirconate (ZrF6-2), and mixtures thereof;
(B) an amount, measured in grams of its stoichiometric equivalent as fluoride ions per kilogram of total composition, of a water soluble component providing in aqueous solution ions selected from the group consisting of fluoride (F-), bifluoride (HF2-), and mixtures thereof;
(C) an amount, measured in grams of its stoichiometric equivalent as citric acid per kilogram of total composition, of a water soluble iron chelating agent component selected from the group consisting of citric acid, salts of citric acid, and mixtures of any two or more of these;
(D) an amount, measured in grams of its stoichiometric equivalent as hydroxylamine per kilogram of total composition, of a water soluble component source of dissolved hydroxylamine in aqueous solution;
(E) an amount, measured in grams of its stoichiometric equivalent as phosphate ions per kilogram of total composition, of a water soluble source of dissolved phosphate ions; and (F) an amount, measured in moles per kilogram, of a water soluble component providing in aqueous solution dissolved oxidizing agents selected from the group consisting of (i) p-nitrobenzene sulfonic acid, water soluble salts thereof, and mixtures thereof and (ii) water soluble salts of molybdic acids and mixtures thereof;
wherein:
- the amount of component (A) has a ratio to the amount of component (B) that is in a range from about 0.3:1.0 to about 1.6:1.0;
- the amount of component (B) has a ratio to the amount of component (C) that is in a range from about 0.30:1.0 to about 8.0:1.0;
- the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.05:1.0 to about 5.0:1.0;
- the amount of component (D) has a ratio to the amount of component (E) that is in a range from about 0.05:1.0 to about 5.0:1.0; and - the amount of component (E) has a ratio to the amount of component (F) that is in a range from about 2000:1.0 to about 20,000:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in a range from about 400:1.0 to about 4000:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, water soluble salts thereof, or mixtures thereof.
2. A liquid aqueous composition according to claim 1, wherein:
- the amount of component (A) has a ratio to the amount of component (B) that is in a range from about 0.5:1.0 to about 1.3:1.0;
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 0.35:1.0 to about 6.0:1.0;
- the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.100:1.0 to about 4.0:1.0;
- the amount of component (D) has a ratio to the amount of component (E) that is in a range from about 1:80 to about 1:8; and - the amount of component (E) has a ratio to the amount of component (F} that is in a range from about 4300:1.0 to about 12,825:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in a range from about 860:1.0 to about 2565:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, water soluble salts thereof, or mixtures thereof.
- the amount of component (A) has a ratio to the amount of component (B) that is in a range from about 0.5:1.0 to about 1.3:1.0;
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 0.35:1.0 to about 6.0:1.0;
- the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.100:1.0 to about 4.0:1.0;
- the amount of component (D) has a ratio to the amount of component (E) that is in a range from about 1:80 to about 1:8; and - the amount of component (E) has a ratio to the amount of component (F} that is in a range from about 4300:1.0 to about 12,825:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in a range from about 860:1.0 to about 2565:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, water soluble salts thereof, or mixtures thereof.
3. A liquid aqueous composition according to claim 2, wherein:
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 0.55:1.0 to about 4.5:1.0; and - the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.160:1.0 to about 2.5:1Ø
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 0.55:1.0 to about 4.5:1.0; and - the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.160:1.0 to about 2.5:1Ø
4. A liquid aqueous composition according to claim 3, wherein:
the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 0.75:1.0 to about 3.1:11.0; and - the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.250:1.0 to about 1.5:1Ø
the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 0.75:1.0 to about 3.1:11.0; and - the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.250:1.0 to about 1.5:1Ø
5. A liquid aqueous composition according to claim 4, wherein:
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 1.05:1.0 to about 2.2:1.0; and - the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.340:1.0 to about 0.80:1Ø
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 1.05:1.0 to about 2.2:1.0; and - the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.340:1.0 to about 0.80:1Ø
6. A liquid aqueous composition according to claim 5, wherein:
- the amount of component (A) has a ratio to the amount of component (B) that is in a range from about 0.6:1.0 to about 0.9:1.0;
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 1.45:1.0 to about 1.90:1.0;
- the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.440:1.0 to about 0.55:1.0;
- the amount of component (D) has a ratio to the amount of component (E) that is in a range from about 1:40 to about 1:21; and - the amount of component (E) has a ratio to the amount of component (F) that is in a range from about 7000:1.0 to about 9000:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in a range from about 1400:1.0 to about 1800:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, water soluble salts thereof, or mixtures thereof.
- the amount of component (A) has a ratio to the amount of component (B) that is in a range from about 0.6:1.0 to about 0.9:1.0;
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 1.45:1.0 to about 1.90:1.0;
- the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.440:1.0 to about 0.55:1.0;
- the amount of component (D) has a ratio to the amount of component (E) that is in a range from about 1:40 to about 1:21; and - the amount of component (E) has a ratio to the amount of component (F) that is in a range from about 7000:1.0 to about 9000:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in a range from about 1400:1.0 to about 1800:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, water soluble salts thereof, or mixtures thereof.
7. A composition according to claim 1 that is a working composition, wherein is contained:
- from about 0.05 to about 1 g/kg of component (A);
- from about 0.1 to about 2 g/kg of component (B);
- from about 0.0010 to about 0.35 g/kg of component (C);
- from about 0.1 to about 10 g/kg of component (D);
- from about 3 to about 30 g/kg of component (E); and - from about 0.0001 to about 0.1 M of component (F) if component (F) is selected from the group consisting of p-nitrobenzene sulfonic acid, water soluble salts thereof, and mixtures thereof and from about 0.00002 to about 0.02 M of component (F) if component (F) is selected from the group consisting of water soluble salts of molybdic acids or mixtures thereof.
- from about 0.05 to about 1 g/kg of component (A);
- from about 0.1 to about 2 g/kg of component (B);
- from about 0.0010 to about 0.35 g/kg of component (C);
- from about 0.1 to about 10 g/kg of component (D);
- from about 3 to about 30 g/kg of component (E); and - from about 0.0001 to about 0.1 M of component (F) if component (F) is selected from the group consisting of p-nitrobenzene sulfonic acid, water soluble salts thereof, and mixtures thereof and from about 0.00002 to about 0.02 M of component (F) if component (F) is selected from the group consisting of water soluble salts of molybdic acids or mixtures thereof.
8. A composition according to claim 7, wherein is contained:
- from about 0.10 to about 0.70 g/kg of component (A);
- from about 0.2 to about 0.8 g/kg of component (B);
- from about 0.0050 to about 0.25 g/kg of component (C);
- from about 0.5 to about 6 g/kg of component (D);
- from about 7 to about 15 g/kg of component (E); and - from about 0.001 to about 0.1 M of component (F) if component (F) is selected from the group consisting of p-nitrobenzene sulfonic acid, water soluble salts thereof, and mixtures thereof and from about 0.0002 to about 0.02 M of component (F) if component (F) is selected from the group consisting of water soluble salts of molybdic acids or mixtures thereof.
- from about 0.10 to about 0.70 g/kg of component (A);
- from about 0.2 to about 0.8 g/kg of component (B);
- from about 0.0050 to about 0.25 g/kg of component (C);
- from about 0.5 to about 6 g/kg of component (D);
- from about 7 to about 15 g/kg of component (E); and - from about 0.001 to about 0.1 M of component (F) if component (F) is selected from the group consisting of p-nitrobenzene sulfonic acid, water soluble salts thereof, and mixtures thereof and from about 0.0002 to about 0.02 M of component (F) if component (F) is selected from the group consisting of water soluble salts of molybdic acids or mixtures thereof.
9. A composition according to claim 8, wherein is contained from about 0.020 to about 0.20 g/kg of component (C).
10. A composition according to claim 9, wherein:
- component (A) is supplied by acids, alkali metal salts, ammonium salts, or mixtures of one or more thereof;
- component (B) is supplied from the group consisting of hydrofluoric acid, alkali metal fluoride and bifluoride salts, and ammonium fluoride and bifluoride;
- the composition contains from about 0.040 to about 0.20 g/kg of component (C);
- component (E) is supplied from the group consisting of orthophosphoric acid and its alkali metal and ammonium salts; and - component (F) is constituted either of water soluble salts of molybdic acids or of material selected from the group consisting of paranitrobenzene sulfonic acid and its water soluble salts.
- component (A) is supplied by acids, alkali metal salts, ammonium salts, or mixtures of one or more thereof;
- component (B) is supplied from the group consisting of hydrofluoric acid, alkali metal fluoride and bifluoride salts, and ammonium fluoride and bifluoride;
- the composition contains from about 0.040 to about 0.20 g/kg of component (C);
- component (E) is supplied from the group consisting of orthophosphoric acid and its alkali metal and ammonium salts; and - component (F) is constituted either of water soluble salts of molybdic acids or of material selected from the group consisting of paranitrobenzene sulfonic acid and its water soluble salts.
11. A composition according to claim 10 that additionally contains from about 1.5 to about 3.0 g/kg of a component (G) of surfactant molecules selected from the group consisting of polyethoxylated alcohols with from about 12 to about 22 carbon atoms in their alcohol portion, nonionic polyethers, and salts of partial esters of phosphoric acid with alcohols having from about 12 to about 22 carbon atoms in their alcohol portion.
12. A composition according to claim 11, wherein is contained:
- from about 0.30 to about 0.50 g/kg of component (A);
- from about 0.4 to about 0.7 g/kg of component (B);
- from about 0.070 to about 0.15 g/kg of component (C);
- from about 0.5 to about 2.0 g/kg of component (D);
- from about 5 to about 12 g/kg of component (E);
- from about 0.01 to about 0.1 M of component (F) if component (F) is selected from the group consisting of p-nitrobenzene sulfonic acid, water soluble salts thereof, and mixtures thereof and from about 0.002 to about 0.02 M of component (F) if component (F) is selected from the group consisting of water soluble salts of molybdic acids or mixtures thereof; and - from about 1.5 to about 2.0 g/L of component (G).
- from about 0.30 to about 0.50 g/kg of component (A);
- from about 0.4 to about 0.7 g/kg of component (B);
- from about 0.070 to about 0.15 g/kg of component (C);
- from about 0.5 to about 2.0 g/kg of component (D);
- from about 5 to about 12 g/kg of component (E);
- from about 0.01 to about 0.1 M of component (F) if component (F) is selected from the group consisting of p-nitrobenzene sulfonic acid, water soluble salts thereof, and mixtures thereof and from about 0.002 to about 0.02 M of component (F) if component (F) is selected from the group consisting of water soluble salts of molybdic acids or mixtures thereof; and - from about 1.5 to about 2.0 g/L of component (G).
13. A composition according to claim 12, wherein:
- the amount of component (A) has a ratio to the amount of component (B) that is in a range from about 0.6:1.0 to about 0.9:1.0;
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 1.45:1.0 to about 1.90:1.0;
- the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.440:1.0 to about 0.55:1.0;
the amount of component (D) has a ratio to the amount of component (E) that is in a range from about 1:40 to about 1:21; and the amount of component (E) has a ratio to the amount of component (F) that is in a range from about 7000:1.0 to about 9000:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in a range from about 1400:1.0 to about 1800:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, water-soluble salts thereof, or mixtures thereof.
- the amount of component (A) has a ratio to the amount of component (B) that is in a range from about 0.6:1.0 to about 0.9:1.0;
- the amount of component (B) has a ratio to the amount of component (C) that is in the range from about 1.45:1.0 to about 1.90:1.0;
- the amount of component (C) has a ratio to the amount of component (D) that is in a range from about 0.440:1.0 to about 0.55:1.0;
the amount of component (D) has a ratio to the amount of component (E) that is in a range from about 1:40 to about 1:21; and the amount of component (E) has a ratio to the amount of component (F) that is in a range from about 7000:1.0 to about 9000:1.0 if component (F) is made up of water soluble salts of molybdic acids or mixtures thereof and is in a range from about 1400:1.0 to about 1800:1.0 if component (F) is made up of p-nitrobenzene sulfonic acid, water-soluble salts thereof, or mixtures thereof.
14. A process for forming a phosphate conversion coating on an active metal surface, said process comprising contacting, for a time in a range from about 30 sec to about 5 min, the active metal surface with a liquid aqueous composition according to claim 13 maintained at a temperature in a range from about 30 to about 65 °C, said liquid aqueous composition having a free acid content in a range from about 0.2 to about 1.0 point, a total acid content in a range from about 6.0 to about 9.0 points, and a pH in a range from about 4.5 to about 5.5, so as to produce on the active metal surface a coating with a mass per unit area of surface coated in a range from about 285 to about 700 milligrams per square meter.
15. A process for forming a phosphate conversion coating on an active metal surface, said process comprising contacting, for a time in a range from about 15 sec to about 10 min, the active metal surface with a liquid aqueous composition according to claim 12 maintained at a temperature in a range from about 25 to about 70 °C, said liquid aqueous composition having a free acid content in a range from about 0.0 to about 1.0 point, a total acid content in a range from about 5 to about 10 points, and a pH in a range from about 4.2 to about 5.9, so as to produce on the active metal surface a coating with a mass per unit area of surface coated in a range from about 98 to about 975 milligrams per square meter.
16. A process for forming a phosphate conversion coating on an active metal surface, said process comprising contacting, for a time in a range from about 5 sec to about 15 min, the active metal surface with a liquid aqueous composition according to claim 11 maintained at a temperature in a range from about 21 to about 85 °C, said liquid aqueous composition having a free acid content in a range from about 0.0 to about 2.0 points, a total acid content in a range from about 3 to about 12 points, and a pH in a range from about 3 to about 7, so as to produce on the active metal surface a coating with a mass per unit area of surface coated in a range from about 12 to about 1600 milligrams per square meter.
17. A process for forming a phosphate conversion coating on an active metal surface, said process comprising contacting the active metal surface with a liquid aqueous composition according to claim 10 to produce the phosphate conversion coating on the active metal surtace.
18. A process for forming a phosphate conversion coating on an active metal surface, said process comprising contacting the active metal surface with a liquid aqueous composition according to claim 9 to produce the phosphate conversion coating on the active metal surface.
19. A process for forming a phosphate conversion coating on an active metal surface, said process comprising contacting the active metal surface with a liquid aqueous composition according to claim 8 to produce the phosphate conversion coating on the active metal surtace.
20. A process for forming a phosphate conversion coating on an active metal surtace, said process comprising contacting the active metal surtace with a liquid aqueous composition according to claim 7 to produce the phosphate conversion coating on the active metal surface.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US2955796P | 1996-11-06 | 1996-11-06 | |
| US60/029,557 | 1996-11-06 | ||
| PCT/US1997/019313 WO1998020186A1 (en) | 1996-11-06 | 1997-11-04 | Phosphate conversion coating composition and process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2269455A1 true CA2269455A1 (en) | 1998-05-14 |
Family
ID=21849644
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002269455A Abandoned CA2269455A1 (en) | 1996-11-06 | 1997-11-04 | Phosphate conversion coating composition and process |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU5087798A (en) |
| CA (1) | CA2269455A1 (en) |
| WO (1) | WO1998020186A1 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19933189A1 (en) * | 1999-07-15 | 2001-01-18 | Henkel Kgaa | Process for the protection against corrosion or aftertreatment of metal surfaces |
| US6887320B2 (en) * | 2002-02-11 | 2005-05-03 | United Technologies Corporation | Corrosion resistant, chromate-free conversion coating for magnesium alloys |
| EP1386952A3 (en) | 2002-08-02 | 2006-05-24 | Clariant Produkte (Deutschland) GmbH | Antifreeze agent |
| US7641744B2 (en) | 2005-04-06 | 2010-01-05 | Rem Technologies, Inc. | Superfinishing of high density carbides |
| US7695771B2 (en) * | 2005-04-14 | 2010-04-13 | Chemetall Gmbh | Process for forming a well visible non-chromate conversion coating for magnesium and magnesium alloys |
| IT1397902B1 (en) * | 2010-01-26 | 2013-02-04 | Np Coil Dexter Ind Srl | PRETREATMENT PROCESSES FOR PAINTING, LOW ENVIRONMENTAL IMPACT, ALTERNATIVE TO TRADITIONAL PHOSPHATE TREATMENTS. |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01100281A (en) * | 1987-10-13 | 1989-04-18 | Nippon Parkerizing Co Ltd | Chemical conversion coating liquid for surface of metal |
| US5143562A (en) * | 1991-11-01 | 1992-09-01 | Henkel Corporation | Broadly applicable phosphate conversion coating composition and process |
-
1997
- 1997-11-04 WO PCT/US1997/019313 patent/WO1998020186A1/en active Application Filing
- 1997-11-04 AU AU50877/98A patent/AU5087798A/en not_active Abandoned
- 1997-11-04 CA CA002269455A patent/CA2269455A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| AU5087798A (en) | 1998-05-29 |
| WO1998020186A1 (en) | 1998-05-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5143562A (en) | Broadly applicable phosphate conversion coating composition and process | |
| US5449415A (en) | Composition and process for treating metals | |
| KR100250366B1 (en) | Acid aqueous compositions and concentration in order to make zinc phosphate coating on the meal plate | |
| US6193815B1 (en) | Composition and process for treating the surface of aluminiferous metals | |
| US5683816A (en) | Passivation composition and process for zinciferous and aluminiferous surfaces | |
| WO1995014539A1 (en) | Composition and process for treating metal | |
| EP0866887A1 (en) | Finely crystalline and/or fast phosphate conversion coating composition and process | |
| CA2252559C (en) | Chromate passivating and storage stable concentrate solutions therefor | |
| US20080314479A1 (en) | High manganese cobalt-modified zinc phosphate conversion coating | |
| CA2269455A1 (en) | Phosphate conversion coating composition and process | |
| EP1287180B1 (en) | Phosphate conversion coating process and composition | |
| US6706123B2 (en) | Phosphate conversion coating concentrate | |
| US5993567A (en) | Compositions and processes for forming a solid adherent protective coating on metal surfaces | |
| AU712410B2 (en) | Moderate temperature manganese phosphate conversion coating composition and process | |
| WO2006071226A1 (en) | Iron phosphating process that reduces laser scale resulting in improved paint adhesion | |
| CA2242995C (en) | Passivation composition and process for zinciferous and aluminiferous surfaces | |
| CA2244902C (en) | Moderate temperature manganese phosphate conversion coating composition and process | |
| CA2236173A1 (en) | Finely crystalline and/or fast phosphate conversion coating composition and process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |