CA2378935A1 - Method for applying products without rinsing on moving metal strips - Google Patents
Method for applying products without rinsing on moving metal strips Download PDFInfo
- Publication number
- CA2378935A1 CA2378935A1 CA002378935A CA2378935A CA2378935A1 CA 2378935 A1 CA2378935 A1 CA 2378935A1 CA 002378935 A CA002378935 A CA 002378935A CA 2378935 A CA2378935 A CA 2378935A CA 2378935 A1 CA2378935 A1 CA 2378935A1
- Authority
- CA
- Canada
- Prior art keywords
- solution
- metal strips
- treatment
- roller
- woven
- 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
- C23C22/73—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 characterised by the process
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D1/00—Processes for applying liquids or other fluent materials
- B05D1/28—Processes for applying liquids or other fluent materials performed by transfer from the surfaces of elements carrying the liquid or other fluent material, e.g. brushes, pads, rollers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C1/00—Apparatus in which liquid or other fluent material is applied to the surface of the work by contact with a member carrying the liquid or other fluent material, e.g. a porous member loaded with a liquid to be applied as a coating
- B05C1/04—Apparatus in which liquid or other fluent material is applied to the surface of the work by contact with a member carrying the liquid or other fluent material, e.g. a porous member loaded with a liquid to be applied as a coating for applying liquid or other fluent material to work of indefinite length
- B05C1/08—Apparatus in which liquid or other fluent material is applied to the surface of the work by contact with a member carrying the liquid or other fluent material, e.g. a porous member loaded with a liquid to be applied as a coating for applying liquid or other fluent material to work of indefinite length using a roller or other rotating member which contacts the work along a generating line
- B05C1/0808—Details thereof, e.g. surface characteristics
Landscapes
- Chemical & Material Sciences (AREA)
- Metallurgy (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
- Chemical Treatment Of Metals (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
- Catalysts (AREA)
- Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
- Treatment Of Fiber Materials (AREA)
Abstract
The invention concerns a method for chemical treatment of metal strips which consists in applying unilaterally or bilaterally a treating liquid on the surface of metal strips using a roller coater, and in drying said liquid without intermediate rinsing. Said method is characterised in that it consists in using a lap roll as roller coater. The treating liquid is preferably a phosphating solution, a chromating solution, an acid or alkaline passivating solution, a treating solution based on complex fluorides or a solution or dispersion of an organic film-forming agent.
Description
' ' CA 02378935 2002-O1-10 "A process for applying no-rinse products to continuous metal strips"
This invention relates to the field of corrosion-protective surface treatment of metal strips. It relates specifically to the application of so-called no-rinse products, that is products which are dried immediately after application without first being rinsed with water. This means that all non-volatile components in the treatment solution being used and products of the reaction with the metal surface remain on the metal. One advantage of this technique is that no product-polluted wash-water which has. to be disposed of in a costly manner is produced. Traditionally, the treatment solutions are applied to the metal strips via rollers having a hard surface, these being known as Chemcoaters or Rollcoaters. An alternative to this method is the so-called spray/dip-squeeze technology in which the surface is briefly contacted with the treatment solution being applied, by spraying or immersion, after which the treatment solution is squeezed off using rollers and then the surface is dried.
A disadvantage of Chemcoaters is the high investment and operating cost. A
disadvantage of the spray/dip-squeeze method is that the wet-filrr~ thickness depends on the running time of the squeezing rollers, different rates of appli~~ation of the film also being obtained in the edge regions on changing the width. The coating on the strip is then uneven. Furthermore, since the wet film is very thin (generally thinner than 2 Vim) after being squeezed off, small changes in the wet film thickness are very noticeable in the final layer which is produced.
An object of the present invention is to provide an improved application system for no-rinse products which does not have the disadvantages mentioned above.
The present invention also provides a process for the chemical treatment of metal strips, wherein a treatment liquid is applied to the surface of one or both faces of the metal strips using an application roller and dried without an intermediate wash process, characterised in that a non-woven roller is used as the application roller.
This invention relates to the field of corrosion-protective surface treatment of metal strips. It relates specifically to the application of so-called no-rinse products, that is products which are dried immediately after application without first being rinsed with water. This means that all non-volatile components in the treatment solution being used and products of the reaction with the metal surface remain on the metal. One advantage of this technique is that no product-polluted wash-water which has. to be disposed of in a costly manner is produced. Traditionally, the treatment solutions are applied to the metal strips via rollers having a hard surface, these being known as Chemcoaters or Rollcoaters. An alternative to this method is the so-called spray/dip-squeeze technology in which the surface is briefly contacted with the treatment solution being applied, by spraying or immersion, after which the treatment solution is squeezed off using rollers and then the surface is dried.
A disadvantage of Chemcoaters is the high investment and operating cost. A
disadvantage of the spray/dip-squeeze method is that the wet-filrr~ thickness depends on the running time of the squeezing rollers, different rates of appli~~ation of the film also being obtained in the edge regions on changing the width. The coating on the strip is then uneven. Furthermore, since the wet film is very thin (generally thinner than 2 Vim) after being squeezed off, small changes in the wet film thickness are very noticeable in the final layer which is produced.
An object of the present invention is to provide an improved application system for no-rinse products which does not have the disadvantages mentioned above.
The present invention also provides a process for the chemical treatment of metal strips, wherein a treatment liquid is applied to the surface of one or both faces of the metal strips using an application roller and dried without an intermediate wash process, characterised in that a non-woven roller is used as the application roller.
Non-woven rollers, termed 'soft rolls', are currently used in the continuous strip industry as squeezing rollers. The surface of these rollers consists of a soft covering, generally made of a chemicals-resistant matted fibrous material. Examples .are polyamide (nylon) or polypropylene fibrous materials. In general, any fibres may bc: used which have an adequate absorption volume and adequate resistance to strongly acid or alkaline solutions. In the process according to the present invention, these rollers may rotate in the opposite direction to or the same direction as the metal strip.
The gap between the non-woven rollers is preferably adjusted as a function of the thickness of the metal sheeting in such a way that the treatment liquid is applied to the surface of the metal strips by the non-woven roller with a wet film thickness of 1 to 10 Vim. This is the case, for example, using a gap width between 0.3 ~~nd 0.8 mm.
The roller gap is preferably adjusted so that a wet film thickness of 2 to 6 pm (corresponding to ml/m2) is produced on the surface of the metal strips.
In accordance with the present process, any treatment solutions which are suitable for a no-rinse method may be applied. These treatment liquids are generally adjusted to be either acid (pH between 0 and 7) or alkaline (pH between 7 and l~l). The composition of the treatment solutions is generally selected so that a chemical reaction occurs with the metal surface. Large numbers of these types of treatment solutions are known from the prior art. The following may be mentioned by way of example:
Phosphatising solutions: acidic, phosphorus-containing solutions which produce a crystalline or amorphous layer of metal phosphate on the metal surface. These solutions generally contain zinc ions, frequently together with manganese andlor nickel ions, as canons.
Chromatising solutions: acidic solutions which contain Cr(VI) ions and frequently also Cr(111) ions.
The gap between the non-woven rollers is preferably adjusted as a function of the thickness of the metal sheeting in such a way that the treatment liquid is applied to the surface of the metal strips by the non-woven roller with a wet film thickness of 1 to 10 Vim. This is the case, for example, using a gap width between 0.3 ~~nd 0.8 mm.
The roller gap is preferably adjusted so that a wet film thickness of 2 to 6 pm (corresponding to ml/m2) is produced on the surface of the metal strips.
In accordance with the present process, any treatment solutions which are suitable for a no-rinse method may be applied. These treatment liquids are generally adjusted to be either acid (pH between 0 and 7) or alkaline (pH between 7 and l~l). The composition of the treatment solutions is generally selected so that a chemical reaction occurs with the metal surface. Large numbers of these types of treatment solutions are known from the prior art. The following may be mentioned by way of example:
Phosphatising solutions: acidic, phosphorus-containing solutions which produce a crystalline or amorphous layer of metal phosphate on the metal surface. These solutions generally contain zinc ions, frequently together with manganese andlor nickel ions, as canons.
Chromatising solutions: acidic solutions which contain Cr(VI) ions and frequently also Cr(111) ions.
Acid or alkaline passivating solutions: aqueous solutions which generally contain transition metal ions and which produce a corrosion-protective amorphous (mixed) oxide layer after drying.
Treatment solutions based on complex fluorides: generally acidic solutions of, for example, hexafluorozirconic acid, hexafluorotitanic acid, hexafluorosilicic acid and also the particular salts thereof.
Solutions or dispersions of organic film-formers, for example polyacrylates.
In this case, the solution may contain inorganic reactive components, such as complex fluorides, in addition to the film-formers. An inorganic/organic polymeric mixed layer is produced therefrom.
These treatment solutions are currently used for treating a variety of different substrates in conventional application processes. They are adjusted to be appropriate for the metal surface being treated and are suitable, for example, for treating steel, galvanised or alloy-galvanised steel, alloy-aluminised steel and also for treating ;aluminum and alloys thereof. Accordingly, the process according to the present invention may be used to treat strips made from the materials mentioned, using these types of treatment liquids.
The treatment solution may be applied to the surface of the non-woven rollers in a variety of ways. For example, it is possible to spray it onto the sur~_ace of the non-woven rollers via nozzles. As an alternative, it may be transferred to the surface of the non-woven rollers from a storage container, via transfer-rollers.
An alternative involves applying the treatment liquid to the surf~~ce of the non-woven rollers via the internal cavity in the non-woven rollers. This is possible because the wall of the non-woven roller may be designed to be permeable to liquids. Treatment liquid fed to the interior of the non-woven roller, for example, via a hollow roller shaft, may reach the surface thereof via holes in the wall of the roller.
Treatment solutions based on complex fluorides: generally acidic solutions of, for example, hexafluorozirconic acid, hexafluorotitanic acid, hexafluorosilicic acid and also the particular salts thereof.
Solutions or dispersions of organic film-formers, for example polyacrylates.
In this case, the solution may contain inorganic reactive components, such as complex fluorides, in addition to the film-formers. An inorganic/organic polymeric mixed layer is produced therefrom.
These treatment solutions are currently used for treating a variety of different substrates in conventional application processes. They are adjusted to be appropriate for the metal surface being treated and are suitable, for example, for treating steel, galvanised or alloy-galvanised steel, alloy-aluminised steel and also for treating ;aluminum and alloys thereof. Accordingly, the process according to the present invention may be used to treat strips made from the materials mentioned, using these types of treatment liquids.
The treatment solution may be applied to the surface of the non-woven rollers in a variety of ways. For example, it is possible to spray it onto the sur~_ace of the non-woven rollers via nozzles. As an alternative, it may be transferred to the surface of the non-woven rollers from a storage container, via transfer-rollers.
An alternative involves applying the treatment liquid to the surf~~ce of the non-woven rollers via the internal cavity in the non-woven rollers. This is possible because the wall of the non-woven roller may be designed to be permeable to liquids. Treatment liquid fed to the interior of the non-woven roller, for example, via a hollow roller shaft, may reach the surface thereof via holes in the wall of the roller.
The treatment solution is preferably applied to the metal strips at a temperature from about 15 to about 40°C, in particular between 20 and 30°C. Then the metal strips are dried without an intermediate wash process. The time betwec,n application of the treatment liquid by the non-woven roller and the start of drying should then be not shorter than 1 second and not longer than 15 seconds. Drying itsc;lf may be performed, for example, in a circulating air oven, as is conventionally the case in a no-rinse process.
If production is interrupted, it is recommended that any treatment solution remaining on the non-woven roller be washed off. This may take place, for example, by spraying with water. If the non-woven roller is designed so that the surface is fecL with treatment liquid via the internal cavity, washing is preferably also performed via th~~
internal cavity of the non-woven roller.
The process according to the present invention has the advantage that even when changing the width of the strips, uniform application of the treatment liquid over the entire width of the strip is facilitated. This avoids different regions of the strips being coated with different thicknesses.
-S-Examples Using a polypropylene non-woven roller from the Thomas Rolls Co., the following applications were achieved. The thickness of the sheeting being treated was 0.75 mm:
Ingredients in the pH Direction Gap Wet ' Rate of treatment solution of (mm) film application (g/1): rotation 4.5 Mn; 3.5 Ti; 2.3 same 0.5 3 10 mg/m2 ~m Ti 8.2 fluoride;
8.3 phosphate;
50.0 polyglucamine derivative (GranodineR 1455 Henkel KGaA) reverse 0.6 4 13 mg/m2 um Ti 87.4 phosphate; 2.0 same 0.7 5 1.1 g/m2 4.4 ~m of Ca; 3.1 Zn; 3.2 coating Ni;
7.9 Mn; 0.3 Fe(II);
0.5 sulfate (GranodineR 5893 Henkel KGaA) reverse 0.6 4 0.9 g/mz ~m of coating 6.2 Cr(III); 12.7 2.6 reverse 0.4 2 20 mg/mz ~m Cr Cr(VI); 1.6 phosphate; 7.4 Si;
(GranodineR 1402 W
Henkel KGaA) 4.8 Zr; 5.9 fluoride;1.2 reverse 0.5 3 15 mg/mz ~m Zr 5.3 phosphate;
0.3 polyacrylic acid (AlodineR 778 Henkel KGaA)
If production is interrupted, it is recommended that any treatment solution remaining on the non-woven roller be washed off. This may take place, for example, by spraying with water. If the non-woven roller is designed so that the surface is fecL with treatment liquid via the internal cavity, washing is preferably also performed via th~~
internal cavity of the non-woven roller.
The process according to the present invention has the advantage that even when changing the width of the strips, uniform application of the treatment liquid over the entire width of the strip is facilitated. This avoids different regions of the strips being coated with different thicknesses.
-S-Examples Using a polypropylene non-woven roller from the Thomas Rolls Co., the following applications were achieved. The thickness of the sheeting being treated was 0.75 mm:
Ingredients in the pH Direction Gap Wet ' Rate of treatment solution of (mm) film application (g/1): rotation 4.5 Mn; 3.5 Ti; 2.3 same 0.5 3 10 mg/m2 ~m Ti 8.2 fluoride;
8.3 phosphate;
50.0 polyglucamine derivative (GranodineR 1455 Henkel KGaA) reverse 0.6 4 13 mg/m2 um Ti 87.4 phosphate; 2.0 same 0.7 5 1.1 g/m2 4.4 ~m of Ca; 3.1 Zn; 3.2 coating Ni;
7.9 Mn; 0.3 Fe(II);
0.5 sulfate (GranodineR 5893 Henkel KGaA) reverse 0.6 4 0.9 g/mz ~m of coating 6.2 Cr(III); 12.7 2.6 reverse 0.4 2 20 mg/mz ~m Cr Cr(VI); 1.6 phosphate; 7.4 Si;
(GranodineR 1402 W
Henkel KGaA) 4.8 Zr; 5.9 fluoride;1.2 reverse 0.5 3 15 mg/mz ~m Zr 5.3 phosphate;
0.3 polyacrylic acid (AlodineR 778 Henkel KGaA)
Claims (6)
1. A process for the chemical treatment of metal strips, wherein a treatment liquid is applied to the surface of one or both faces of the metal strips using an application roller and dried without an intermediate wash process, characterised in that a non-woven roller is used as the application roller.
2. A process as claimed in claim 1 wherein the treatment liquid is applied to the surface of the metal strips with a wet film thickness of 1 to 10 µm.
3. A process as claimed in one or both of claims 1 and 2 wherein the treatment liquid is a phosphatising solution, a chromatising solution, an acid or alkaline passivating solution, a treatment solution based on complex fluorides or a solution or dispersion of an organic film-former.
4. A process as claimed in one or more of claims 1 to 3 wherein the treatment liquid is applied to the non-woven roller by spraying or via transfer-rollers.
5. A process as claimed in one or more of claims 1 to 3 wherein the treatment liquid is applied to the surface of the non-woven roller via the internal cavity of the non-woven roller.
6. A process as claimed in one or more of claims 1 to 5 wherein the treatment solution is applied to the metal strips at a temperature of from 15 to 40°C, preferably between 20 and 30°C.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19933186A DE19933186A1 (en) | 1999-07-15 | 1999-07-15 | Process for applying no-rinse products to running metal belts |
| DE19933186.3 | 1999-07-15 | ||
| PCT/EP2000/006398 WO2001006037A1 (en) | 1999-07-15 | 2000-07-06 | Method for applying products without rinsing on moving metal strips |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2378935A1 true CA2378935A1 (en) | 2001-01-25 |
Family
ID=7914900
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002378935A Abandoned CA2378935A1 (en) | 1999-07-15 | 2000-07-06 | Method for applying products without rinsing on moving metal strips |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP1198617B1 (en) |
| AT (1) | ATE233831T1 (en) |
| AU (1) | AU5825800A (en) |
| CA (1) | CA2378935A1 (en) |
| DE (2) | DE19933186A1 (en) |
| TR (1) | TR200103548T2 (en) |
| TW (1) | TW469179B (en) |
| WO (1) | WO2001006037A1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10027444A1 (en) * | 2000-06-02 | 2002-02-14 | Basf Coatings Ag | Coil coating process with powder coating dispersions (powder slurries) |
| DE10115244A1 (en) * | 2001-03-28 | 2002-10-02 | Henkel Kgaa | Post-passivation of a phosphated metal surface using the belt process |
| WO2004074511A1 (en) * | 2003-02-21 | 2004-09-02 | Garvan Institute Of Medical Research | Diagnosis and treatment of baff-mediated autoimmune diseases and cancer |
| DE10357912A1 (en) * | 2003-12-11 | 2005-07-14 | Lutz Freyer | Lubricating device for lubricating sheet metal strips |
| DE102016203771A1 (en) | 2016-03-08 | 2017-09-14 | Henkel Ag & Co. Kgaa | Fluoride-free zirconium-based metal pretreatment for passivation |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5425500B2 (en) * | 1972-11-22 | 1979-08-28 | ||
| GB2018632B (en) * | 1978-04-13 | 1982-07-07 | Bicc Ltd | Sheet processing |
| JPH01149972A (en) * | 1987-12-07 | 1989-06-13 | Kobe Steel Ltd | Manufacture of chromated steel sheet |
| US5116672A (en) * | 1990-02-05 | 1992-05-26 | Sermatech International, Inc. | Organic coatings with ion reactive pigments especially for active metals |
-
1999
- 1999-07-15 DE DE19933186A patent/DE19933186A1/en not_active Withdrawn
-
2000
- 2000-06-15 TW TW089111682A patent/TW469179B/en active
- 2000-07-06 AU AU58258/00A patent/AU5825800A/en not_active Abandoned
- 2000-07-06 CA CA002378935A patent/CA2378935A1/en not_active Abandoned
- 2000-07-06 EP EP00944008A patent/EP1198617B1/en not_active Expired - Lifetime
- 2000-07-06 WO PCT/EP2000/006398 patent/WO2001006037A1/en active IP Right Grant
- 2000-07-06 TR TR2001/03548T patent/TR200103548T2/en unknown
- 2000-07-06 AT AT00944008T patent/ATE233831T1/en not_active IP Right Cessation
- 2000-07-06 DE DE50001405T patent/DE50001405D1/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| DE50001405D1 (en) | 2003-04-10 |
| EP1198617A1 (en) | 2002-04-24 |
| DE19933186A1 (en) | 2001-01-18 |
| TR200103548T2 (en) | 2002-06-21 |
| AU5825800A (en) | 2001-02-05 |
| ATE233831T1 (en) | 2003-03-15 |
| WO2001006037A1 (en) | 2001-01-25 |
| TW469179B (en) | 2001-12-21 |
| EP1198617B1 (en) | 2003-03-05 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |