US2984592A - Protective coatings for galvanized members - Google Patents
Protective coatings for galvanized members Download PDFInfo
- Publication number
- US2984592A US2984592A US722395A US72239558A US2984592A US 2984592 A US2984592 A US 2984592A US 722395 A US722395 A US 722395A US 72239558 A US72239558 A US 72239558A US 2984592 A US2984592 A US 2984592A
- Authority
- US
- United States
- Prior art keywords
- acid
- sheets
- sheet
- galvanized
- solution
- 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.)
- Expired - Lifetime
Links
- 239000011253 protective coating Substances 0.000 title claims description 12
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 claims description 36
- 235000011007 phosphoric acid Nutrition 0.000 claims description 19
- 239000000047 product Substances 0.000 claims description 14
- 239000002253 acid Substances 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 12
- 238000005246 galvanizing Methods 0.000 claims description 7
- 229910001392 phosphorus oxide Inorganic materials 0.000 claims description 6
- 239000002904 solvent Substances 0.000 claims description 6
- UEZVMMHDMIWARA-UHFFFAOYSA-N Metaphosphoric acid Chemical compound OP(=O)=O UEZVMMHDMIWARA-UHFFFAOYSA-N 0.000 claims description 5
- XPPKVPWEQAFLFU-UHFFFAOYSA-N diphosphoric acid Chemical compound OP(O)(=O)OP(O)(O)=O XPPKVPWEQAFLFU-UHFFFAOYSA-N 0.000 claims description 5
- 230000001681 protective effect Effects 0.000 claims description 5
- 229940005657 pyrophosphoric acid Drugs 0.000 claims description 5
- VSAISIQCTGDGPU-UHFFFAOYSA-N tetraphosphorus hexaoxide Chemical compound O1P(O2)OP3OP1OP2O3 VSAISIQCTGDGPU-UHFFFAOYSA-N 0.000 claims description 5
- 230000015572 biosynthetic process Effects 0.000 claims description 4
- 239000010408 film Substances 0.000 claims description 4
- 239000010409 thin film Substances 0.000 claims description 4
- 229910019142 PO4 Inorganic materials 0.000 claims description 3
- 238000001704 evaporation Methods 0.000 claims description 3
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 claims description 3
- 239000010452 phosphate Substances 0.000 claims description 3
- 239000007795 chemical reaction product Substances 0.000 claims description 2
- 238000000151 deposition Methods 0.000 claims description 2
- 239000000243 solution Substances 0.000 description 14
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 9
- 238000005260 corrosion Methods 0.000 description 9
- 230000007797 corrosion Effects 0.000 description 9
- 239000007864 aqueous solution Substances 0.000 description 6
- 239000011248 coating agent Substances 0.000 description 5
- 238000000576 coating method Methods 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000007921 spray Substances 0.000 description 4
- 238000011282 treatment Methods 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- KRVSOGSZCMJSLX-UHFFFAOYSA-L chromic acid Substances O[Cr](O)(=O)=O KRVSOGSZCMJSLX-UHFFFAOYSA-L 0.000 description 3
- AWJWCTOOIBYHON-UHFFFAOYSA-N furo[3,4-b]pyrazine-5,7-dione Chemical compound C1=CN=C2C(=O)OC(=O)C2=N1 AWJWCTOOIBYHON-UHFFFAOYSA-N 0.000 description 3
- 239000011701 zinc Substances 0.000 description 3
- 229910052725 zinc Inorganic materials 0.000 description 3
- 239000005696 Diammonium phosphate Substances 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 2
- 150000003863 ammonium salts Chemical class 0.000 description 2
- ZCDOYSPFYFSLEW-UHFFFAOYSA-N chromate(2-) Chemical class [O-][Cr]([O-])(=O)=O ZCDOYSPFYFSLEW-UHFFFAOYSA-N 0.000 description 2
- MNNHAPBLZZVQHP-UHFFFAOYSA-N diammonium hydrogen phosphate Chemical compound [NH4+].[NH4+].OP([O-])([O-])=O MNNHAPBLZZVQHP-UHFFFAOYSA-N 0.000 description 2
- 229910000388 diammonium phosphate Inorganic materials 0.000 description 2
- 235000019838 diammonium phosphate Nutrition 0.000 description 2
- 239000011574 phosphorus Substances 0.000 description 2
- 229910052698 phosphorus Inorganic materials 0.000 description 2
- -1 phosphorus oxide compound Chemical class 0.000 description 2
- KMUONIBRACKNSN-UHFFFAOYSA-N potassium dichromate Chemical compound [K+].[K+].[O-][Cr](=O)(=O)O[Cr]([O-])(=O)=O KMUONIBRACKNSN-UHFFFAOYSA-N 0.000 description 2
- 238000005507 spraying Methods 0.000 description 2
- JHWIEAWILPSRMU-UHFFFAOYSA-N 2-methyl-3-pyrimidin-4-ylpropanoic acid Chemical compound OC(=O)C(C)CC1=CC=NC=N1 JHWIEAWILPSRMU-UHFFFAOYSA-N 0.000 description 1
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical class N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 1
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Natural products CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 239000000908 ammonium hydroxide Substances 0.000 description 1
- ZRIUUUJAJJNDSS-UHFFFAOYSA-N ammonium phosphates Chemical compound [NH4+].[NH4+].[NH4+].[O-]P([O-])([O-])=O ZRIUUUJAJJNDSS-UHFFFAOYSA-N 0.000 description 1
- 239000011260 aqueous acid Substances 0.000 description 1
- 150000001845 chromium compounds Chemical class 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005367 electrostatic precipitation Methods 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- BDERNNFJNOPAEC-UHFFFAOYSA-N n-propyl alcohol Natural products CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 1
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
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
- C23C22/07—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 phosphates
- C23C22/08—Orthophosphates
-
- 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
- C23C22/07—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 phosphates
- C23C22/23—Condensed phosphates
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/27—Web or sheet containing structurally defined element or component, the element or component having a specified weight per unit area [e.g., gms/sq cm, lbs/sq ft, etc.]
- Y10T428/273—Web or sheet containing structurally defined element or component, the element or component having a specified weight per unit area [e.g., gms/sq cm, lbs/sq ft, etc.] of coating
Definitions
- the present invention relates to a process for applying protective coatings to galvanized members.
- the object of this invention is to provide a process for treating galvanized sheets as they emerge from the galvanizing bath with an aqueous phosphoric acid solution to deposit on the surface a predetermined amount of the phosphorus oxide compound per unit area.
- highly protective coatings that resist formation of white corrosion products may be applied to galvanized sheets by spraying on the freshly galvanized sheets as they emerge from a galvanizing bath and are at a temperature of at least 400 R, an aqueous solution of orthophosphoric acid, metaphosphoric acid and pyrophosphoric acid (or mixture of two or all three) at a concentration equivalent in phosphorus oxide content to that of a .2% to 35% of orthophosphoric acid, to deposit on the galvanized sheets from A; to pounds of H3PO4 per 10,000 square feet of surface.
- the heat of the galvanized sheets evaporates the solvent and promotes a reaction of the phosphoric acid with the hot zinc surface.
- Such protective coating will protect the zinc for from to 30 days when stacked and kept wet.
- the phosphoric acid solutions can include up to 50% based on the weight of H PO for example, of the ammonium salt thereof.
- the ammonium salt may be in- 2,984,592 Patented May 16, 1961 troduced as diammonium phosphate or its equivalent of ammonium hydroxide.
- the galvanized sheets After the galvanized sheets have been treated with the phosphoric acid they may be given an added protective treatment by applying chromic acid or a chromate salt to provide a chromate film thereon.
- chromic acid or a chromate salt to provide a chromate film thereon.
- an aqueous sodium dichromate or potassium dichromate solution of a concentration of l z% or more can be applied to the sheets. After drying, the sheets will better withstand the effects of moisture on a stack of the sheets.
- the phosphoric acid solutions in a concentration of from 5% to 15% give the best results.
- the solvent is preferably water, though monohydric alcohols may be present. Thus ethyl, propyl and methyl alcohol in water form suitable solvents. Water is inexpensive and noninflammable and will ordinarily be the preferred solvent.
- the phosphoric acid solution is applied to the galvanized sheets in the form of a fine spray or mist. From 10% to 20% of the spray will normally contact the freshly galvanized surface. If electrostatic precipitation is employed a much higher proportion of the spray will deposit on the sheet. It is desirable to have the spray contact the sheet as soon as possible after it emerges from the galvanizing bath.
- the optimum amount of solution applied will vary from 2000 to 10,000 square feet of surface per gallon of 10% phosphoric acid solution.
- Example I There is applied to galvanized sheets at a temperature of about 600 F., a 10% aqueous orthophosphoric acid solution at the rate of 32 gallons per 100,000 square feet of surface. It was estimated that there was deposited from A1 to /2 pound of H PO per 10,000 square feet of surface. There was no visually observable deposit on the sheets. The treated sheets could be stacked wet for over 20 days without observing any white corrosion deposits.
- Example II To galvanized sheets emerging from a galvanizing bath there was sprayed an aqueous solution comprising 10% orthophosphoric acid plus 2% diammonium phosphate, at the rate of 1 gallon per 4000 square feet of surface. The treated sheets showed no visible coating. On stacking several sheets wetted with water, they withstood up to 30 days before exhibiting white corrosion products on the surface. Untreated galvanized sheets showed such white products in l to 2 days.
- Example Ill The sheets of Example I were treated with an aqueous .5 solution of chromic acid and dried.
- the steps comprising applying to the surface of a sheet emerging from a galvanizing bath while the sheet is at a temperature of at least 400 F., a thin film of an acid solution consisting essentially of at least one acid from the group consisting of orthophosphoric acid, metaphosphoric acid and pyrophosphoric acid, the concentration of acid in the solution providing phosphorus oxide at a concentration equivalent to that of .2% to 35% orthophosphoric acid, the applied film depositing the equivalent of from /s to 10 pounds of H PO per 10,000 square feet of surface, the heat of the sheets evaporating in a few'seconds the solvent from the applied thin film of the acid solution effecting a highly protective phosphate reaction product on the sheet surface which product is not visually observable.
- the solution is an aqueous solution and contains up to 50%, based on the Weight of the phosphorus acid, of the ammonium phosphate salt.
- phosphoric acid selected from the group consisting of orthophosphoric acid, metaphosphoric acid and pyrophosphoric acid
Landscapes
- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Treatment Of Metals (AREA)
Description
United States Patent PROTECTIVE COATINGS FOR GALVANIZED MEMBERS John E. Logan, Pittsburgh, Pa., assignor to Chem-Metals,
Incorporated, Pittsburgh, Pa., a corporation of Pennsylvania No Drawing. Filed Mar. 19, 1958, Ser. No. 722,395
7 Claims. (Cl. 1486.15)
The present invention relates to a process for applying protective coatings to galvanized members.
It is known that when galvanized sheets or the like are stacked under conditions where moisture is present between superimposed sheets or reaches the edges of the stack, the sheets will show unsightly white corrosion products, or bloom, over considerable areas in a matter of a day or two. This white bloom, or corrosion product, detracts from the value of the galvanized sheets and renders their sale and use less desirable for many purposes.
Numerous treatments have been suggested for preventing such white bloom developing. However, no reasonably economical treatment has been available which would prevent such white corrosion products from developing in 4 or 5 days at most. It would be desirable to have available an easily applied, low cost treatment which would prevent appreciable white corrosion products in forming between wet galvanized sheets for at least 15 days.
The object of this invention is to provide a process for treating galvanized sheets as they emerge from the galvanizing bath with an aqueous phosphoric acid solution to deposit on the surface a predetermined amount of the phosphorus oxide compound per unit area.
Other objects of the invention will in part be obvious and will, in part, be apparent. For a better understanding of the nature and objects of the invention, reference should be had to the following detailed description.
In accordance with the present invention, it has been discovered that highly protective coatings that resist formation of white corrosion products may be applied to galvanized sheets by spraying on the freshly galvanized sheets as they emerge from a galvanizing bath and are at a temperature of at least 400 R, an aqueous solution of orthophosphoric acid, metaphosphoric acid and pyrophosphoric acid (or mixture of two or all three) at a concentration equivalent in phosphorus oxide content to that of a .2% to 35% of orthophosphoric acid, to deposit on the galvanized sheets from A; to pounds of H3PO4 per 10,000 square feet of surface. The heat of the galvanized sheets evaporates the solvent and promotes a reaction of the phosphoric acid with the hot zinc surface. Such protective coating will protect the zinc for from to 30 days when stacked and kept wet.
It appears that reactions between phosphoric acid and zinc at temperatures substantially below 400 F. do not result in a coating which comparm in protective quality to the protective coatings of this invention, since they are only suflicient to prevent White oxide corrosion products from forming for not over 5 days. Furthermore, the process of the present invention is carried out rapidly since the applied aqueous solutions dry out rapidly and only a few seconds are required.
The phosphoric acid solutions can include up to 50% based on the weight of H PO for example, of the ammonium salt thereof. The ammonium salt may be in- 2,984,592 Patented May 16, 1961 troduced as diammonium phosphate or its equivalent of ammonium hydroxide.
After the galvanized sheets have been treated with the phosphoric acid they may be given an added protective treatment by applying chromic acid or a chromate salt to provide a chromate film thereon. Thus an aqueous sodium dichromate or potassium dichromate solution of a concentration of l z% or more can be applied to the sheets. After drying, the sheets will better withstand the effects of moisture on a stack of the sheets.
The phosphoric acid solutions in a concentration of from 5% to 15% give the best results. The solvent is preferably water, though monohydric alcohols may be present. Thus ethyl, propyl and methyl alcohol in water form suitable solvents. Water is inexpensive and noninflammable and will ordinarily be the preferred solvent.
The phosphoric acid solution is applied to the galvanized sheets in the form of a fine spray or mist. From 10% to 20% of the spray will normally contact the freshly galvanized surface. If electrostatic precipitation is employed a much higher proportion of the spray will deposit on the sheet. It is desirable to have the spray contact the sheet as soon as possible after it emerges from the galvanizing bath.
The optimum amount of solution applied will vary from 2000 to 10,000 square feet of surface per gallon of 10% phosphoric acid solution.
The following examples illustrate the practice of the invention:
Example I There is applied to galvanized sheets at a temperature of about 600 F., a 10% aqueous orthophosphoric acid solution at the rate of 32 gallons per 100,000 square feet of surface. It was estimated that there was deposited from A1 to /2 pound of H PO per 10,000 square feet of surface. There was no visually observable deposit on the sheets. The treated sheets could be stacked wet for over 20 days without observing any white corrosion deposits.
Example II To galvanized sheets emerging from a galvanizing bath there was sprayed an aqueous solution comprising 10% orthophosphoric acid plus 2% diammonium phosphate, at the rate of 1 gallon per 4000 square feet of surface. The treated sheets showed no visible coating. On stacking several sheets wetted with water, they withstood up to 30 days before exhibiting white corrosion products on the surface. Untreated galvanized sheets showed such white products in l to 2 days.
Freshly galvanized sheets were treated with aqueous 10% metaphosphoric acid and 10% pyrophosphoric acid solutions, respectively, at the rate of Example I, following the process of Example I. Equally satisfactory protective coatings were obtained.
Example Ill The sheets of Example I were treated with an aqueous .5 solution of chromic acid and dried.
On tests for development of white corrosion products, stacks of the sheets withstood over 20 days before showing any white areas.
It will be understood that the above examples are illustrative and not limiting.
I claim:
1. In the process of producing a protective coating on a galvanized sheet which will reduce and greatly delay the formation of white oxide products between sheets when wet, the steps comprising applying to the surface of a sheet emerging from a galvanizing bath while the sheet is at a temperature of at least 400 F., a thin film of an acid solution consisting essentially of at least one acid from the group consisting of orthophosphoric acid, metaphosphoric acid and pyrophosphoric acid, the concentration of acid in the solution providing phosphorus oxide at a concentration equivalent to that of .2% to 35% orthophosphoric acid, the applied film depositing the equivalent of from /s to 10 pounds of H PO per 10,000 square feet of surface, the heat of the sheets evaporating in a few'seconds the solvent from the applied thin film of the acid solution effecting a highly protective phosphate reaction product on the sheet surface which product is not visually observable.
2. The process of claim 1 wherein the solution is an aqueous solution and contains up to 50%, based on the Weight of the phosphorus acid, of the ammonium phosphate salt.
3. The process of claim 1 wherein the phosphorus acid treated surface is subsequently further coated with a dilute aqueous solution containing a chromium compound selected from the group consisting of chromic acid and alkali metal chromates and dichromates.
4. The process of producing a protective coating on galvanized sheets which will reduce and greatly delay the formation of white oxide products between sheets when wet, the steps comprising spraying the surface of a galvanized sheet as it emerges from a galvanizing bath while the sheet is at a temperature above 400 F. with an aqueous solution of at least one phosphoric acid selected from the group consisting of orthophosphoric acid, metaphosphoric acid and pyrophosphoric acid at a concentration of from 5% to 15% of the acid, the aqueous acid being applied at a rate of 1 gallon of acid to from 10,000 to 2000 square feet of surface, the heat in the '4 sheets evaporating in a few seconds the water in the ap plied sprayed coating and effecting a reaction resulting in a highly protective and visually non-observable phosphate film.
5. The process of claim 4, wherein up to of the acid is present in the form of the ammonia salt thereof.
6. Galvanized sheets bearing on their surfaces a protective coating of phosphorus oxide equivalent to from Vs to 10 pounds of H PO per 10,000 square feet of the surface, the coating having been applied by the process of claim 1.
7. Galvanized sheets bearing on their surfaces a protective coating of phosphorus oxide equivalent to from A; to 10 pounds of H PO per 10,000 square feet of the surface, the coating having been applied 'by the process of claim 5.
References Cited in the file of this patent UNITED STATES PATENTS (1st addition to No. 1,070,671)
Claims (1)
1. IN THE PROCESS OF PRODUCING A PROTECTIVE COATING ON A GALVANIZED SHEET WHICH WILL REDUCE AND GREATLY DELAY THE FORMATION OF WHITE OXIDE PRODUCTS BETWEEN SHEETS WHEN WET, THE STEPS COMPRISING APPLYING TO THE SURFACE OF A SHEET EMERGING FROM A GALVANIZING BATH WILE THE SHEET IS AT A TEMPERATURE OF AT LEAST 400*F., A THIN FILM OF AN ACID SOLUTION CONSISTING ESSENTIALLY OF AT LEAST ONE ACID FROM THE GROUP CONSISTING OF ORTHOPHOSPHORIC ACID, METAPHOSPHORIC ACID AND PYROPHOSPHORIC ACID, THE CONCENTRATION OF ACID IN THE SOLUTION PROVIDING PHOSPHORUS OXIDE AT A CONCENTRATION EQUIVALENT TO THAT OF .2% TO 35% ORTHOPHOSPHORIC AVID, THE APPLIED FILM DEPOSITING THE EQUIVALENT OF FROM 1/8 TO 10 POUNDS OF H3PO4 PER 10,000 SQUARE FEET OF SURFACE, THE HEAT OF THE SHEETS EVAPORATING IN A FEW SECOND THE SOLVENT FROM THE APPLIED THIN FILM OF THE ACID SOLUTION EFFECTING A HIGHLY PROTECTIVE PHOSPHATE REACTION PRODUCT ON THE SHEET SURFACE WHICH PRODUCT IS NOT VISUALLY OBSERVABLE.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US722395A US2984592A (en) | 1958-03-19 | 1958-03-19 | Protective coatings for galvanized members |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US722395A US2984592A (en) | 1958-03-19 | 1958-03-19 | Protective coatings for galvanized members |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2984592A true US2984592A (en) | 1961-05-16 |
Family
ID=24901651
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US722395A Expired - Lifetime US2984592A (en) | 1958-03-19 | 1958-03-19 | Protective coatings for galvanized members |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2984592A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4231812A (en) * | 1978-03-14 | 1980-11-04 | Centre De Recherches Metallurgiques-Centrum Voor Research In De Metallurgie | Surface treatment of metal strip |
| WO2014138361A3 (en) * | 2013-03-06 | 2015-10-08 | Quaker Chemical Corporation | High temperature conversion coating on ferriferous substrates |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1273358A (en) * | 1918-03-23 | 1918-07-23 | James H Gravell | Galvanized iron. |
| US1525904A (en) * | 1922-12-07 | 1925-02-10 | William H Allen | Protecting coating and process for producing same |
| US1761186A (en) * | 1928-06-30 | 1930-06-03 | Parker Rust Proof Co | Process of treating ferrous metal articles |
| US2210850A (en) * | 1938-05-05 | 1940-08-06 | Curtin Howe Corp | Method of finishing ferrous metal surfaces |
| US2528787A (en) * | 1947-09-08 | 1950-11-07 | Hall Lab Inc | Protection of metals from corrosion |
| US2665231A (en) * | 1949-06-17 | 1954-01-05 | Parker Rust Proof Co | Coating process with alkali metal phosphate and added fluoride salt |
| FR1070671A (en) * | 1952-05-05 | 1954-08-05 | Parker Ste Continentale | Process for the deposition of phosphate coatings |
| FR64944E (en) * | 1952-12-17 | 1955-12-14 | Parker Ste Continentale | Process for the deposition of phosphate coatings |
-
1958
- 1958-03-19 US US722395A patent/US2984592A/en not_active Expired - Lifetime
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1273358A (en) * | 1918-03-23 | 1918-07-23 | James H Gravell | Galvanized iron. |
| US1525904A (en) * | 1922-12-07 | 1925-02-10 | William H Allen | Protecting coating and process for producing same |
| US1761186A (en) * | 1928-06-30 | 1930-06-03 | Parker Rust Proof Co | Process of treating ferrous metal articles |
| US2210850A (en) * | 1938-05-05 | 1940-08-06 | Curtin Howe Corp | Method of finishing ferrous metal surfaces |
| US2528787A (en) * | 1947-09-08 | 1950-11-07 | Hall Lab Inc | Protection of metals from corrosion |
| US2665231A (en) * | 1949-06-17 | 1954-01-05 | Parker Rust Proof Co | Coating process with alkali metal phosphate and added fluoride salt |
| FR1070671A (en) * | 1952-05-05 | 1954-08-05 | Parker Ste Continentale | Process for the deposition of phosphate coatings |
| FR64944E (en) * | 1952-12-17 | 1955-12-14 | Parker Ste Continentale | Process for the deposition of phosphate coatings |
| US2813813A (en) * | 1952-12-17 | 1957-11-19 | Parker Rust Proof Co | Process for forming protective phosphate coatings on metallic surfaces |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4231812A (en) * | 1978-03-14 | 1980-11-04 | Centre De Recherches Metallurgiques-Centrum Voor Research In De Metallurgie | Surface treatment of metal strip |
| WO2014138361A3 (en) * | 2013-03-06 | 2015-10-08 | Quaker Chemical Corporation | High temperature conversion coating on ferriferous substrates |
| CN105431568A (en) * | 2013-03-06 | 2016-03-23 | 奎克化学公司 | High temperature conversion coatings on steel and iron substrates |
| US9926628B2 (en) | 2013-03-06 | 2018-03-27 | Quaker Chemical Corporation | High temperature conversion coating on steel and iron substrates |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US2418608A (en) | Corrosion-resistant metallic article and method of making the same | |
| DE69417909T2 (en) | HYDROPHILE COATINGS FOR ALUMINUM | |
| US3706604A (en) | Process for the coating of metal | |
| JP2001107261A (en) | Electrical steel sheet with insulating film | |
| RU2005123323A (en) | METHOD FOR PRODUCING A THIN THIN INHIBITING CORROSION COATING ON A METAL SURFACE | |
| US2318606A (en) | Corrosion inhibition | |
| US4003761A (en) | Process for the production of sprayed phosphate coats on iron and steel | |
| US3553034A (en) | Composition and process for inhibiting corrosion of zinc surfaces | |
| US3036934A (en) | Coated article and method of making same | |
| US3519495A (en) | Process for coating metal surfaces | |
| GB2048961A (en) | Protective compositions for steel surfaces | |
| US2984592A (en) | Protective coatings for galvanized members | |
| US3248350A (en) | Water insoluble coating of methyl vinyl ether-maleic anhydride copolymer, hydroxyethyl cellulose and phosphoric acid | |
| US2316810A (en) | Method of and material for coating metal surfaces with water insoluble metallic phosphates | |
| US3459600A (en) | Novel zinc coating composition and method | |
| US2046061A (en) | Coated metal | |
| US2471907A (en) | Method of and material for increasing the corrosion resistance of ferriferous metals | |
| JPS6158552B2 (en) | ||
| JP3386318B2 (en) | Electromagnetic steel sheet with insulating coating that can be manufactured by low-temperature baking, can perform strain relief annealing, and has good solvent resistance | |
| US3679493A (en) | Glycol ether-chromium corrosion resistant coatings for metallic surfaces | |
| JP3299452B2 (en) | Electromagnetic steel sheet with insulating coating that can be manufactured by low-temperature baking, is capable of strain relief annealing, has good exposure to boiling water vapor, and has excellent solvent resistance. | |
| US3450579A (en) | Process for the chemical surface treatment of metal | |
| US3477882A (en) | Method of and composition for preventing "white rust" formation | |
| US3127288A (en) | Process for coating zinc and zinc-iron | |
| US2216376A (en) | Art of coating metal articles |