CN1784479A - Non-chromate conversion coating treatment for metals - Google Patents

Abstract

Chromate-free treatments and compositions, for applying a conversion or passivation coating to zinc coated metal surfaces. The compositions comprise a polyamidoamine/epihalohydrin polymer or cationic polyamine/epihalohydrin polymer component, fluoacid, H3PO4, and a film forming polymer latex component. The requisite metal surfaces are contacted by the compositions and dried. Rinsing is optional.

Description

The handled thing that is used for the not chromate-containing conversion coating of metal

The cross reference of related application

The application is the U.S. Patent application of submitting on May 6th, 2,003 10/430,579 part continues, this 10/430,579 application itself is that the part of the U.S. Patent application 10/341,164 of submission on January 13rd, 2003 continues, this is 10/341 years old, 164 applications itself are dividing an application of the U.S. Patent application 09/613,529 submitted on July 8th, 1999, and this 09/613,529 applications itself are that the part of the U.S. Patent application 09/348,346 of submission on July 8th, 1999 continues.By reference the disclosure of the application of above-mentioned all this areas of mentioning is incorporated herein at this.

Technical field

The present invention relates to be used for the coating that does not contain chromic salt (chromate) of metal.More specifically, the present invention relates to be used to apply the not chromate-containing coating of the metallic surface of zinc, to improve the binding property of corrosion stability and described surface and coating.The invention provides handling the especially effectively coating of dried in place of galvanized steel winding.

Background technology

The purpose that forms chromate conversion coatings (conversion coating) on the surface of galvanized steel provides corrosion stability, improves the binding property of coating and for aesthetic reason.In order to provide corrosion stability and for the aesthetic reason to the material do not brushed, the chromic salt of passivation surface of galvanized steel.Described conversion coating has improved the binding property of coat (for example coating, printing ink, paint and plastic coating).The common use composition of galvanized steel is handled, and this waterborne compositions comprises sexavalence and trivalent chromic ion, and other additive, to obtain chrome conversion coating.

About the pollution effect that is disposed to the chromic salt in river and the water channel because of described method more and more receives publicity at present.Because the high resolution and the strong oxidizing property of hexavalent chromium, the conventional huge waste treatment step of chromate conversion arts demand is controlled their discharging.In addition, the disposal from the solid mud of this waste treatment step is a serious problem.

Therefore, there is a need in the field to provide effectively conversion or the passivating coating of not chromate-containing handled thing, suppressing the corrosion of metallic surface, and strengthening the binding property that other coating of can be applicable to this metallic surface is coated so that dried in place to be provided.

Summary of the invention

The invention provides the method on a kind of processing zinc-plated (galvanized) metal (for example steel) surface, so that form the corrosion stability of increase surface of galvanized steel and the coating of bond properties.Can dry in position or flushing by passivation or conversion coating that the present invention forms.Method of the present invention comprises makes galvanized metal surfaces contact with aqueous treating composition, and said composition comprises the fluoro-acid (fluoacid) of polyamide-based amine (polyamidoamine)/epihalolhydrin resins or cationic polyamine/epihalohydrin polymers and IVB family metal.In addition, said composition can comprise phosphoric acid and amino silane compounds.Described aqueous treating composition can also comprise the latex polymer film-forming components.

According to following description and appending claims, other purpose of the present invention and advantage will be apparent.

Describe in detail

The present inventor finds, by required surface is contacted with the water-based coating solution or the suspension of the relative dilution of following material, can for example provide improved, not chromate-containing conversion or passivating coating on electro-galvanized steel (galvanizedsteel) surface at galvanized metal surfaces:

(1) polyamide-based amine/epihalolhydrin resins or cationic polyamine/epihalohydrin affixture (adduct); With

(2) fluoro-acid.

Can also there be latex film forming polymkeric substance (3), phosphoric acid (4) and aminosilane ingredient (5).

Have been found that composition of the present invention provides the water-based pretreating agent that is used to handle galvanized metal surfaces, described processing has obtained improved corrosion stability and the binding property of latex applying coating when the handled thing dried in place.

Polyamide-based amine/epihalohydrin or cationic polyamine epihalolhydrin resins component can be bought.For example at United States Patent (USP) 2,926, these materials have been described in 116,2,926,154 and 5,614,597.Preferred polyamide-based amine is polyamide-based amination ammonium (ammonium polyamidoamine), preferred especially crosslinkable poly-azetidine (polyazetidinium) polymkeric substance.According to United States Patent (USP) 4,416, the method of mentioning in 729 can prepare polyamide-based amination ammonium, this method comprises polyamide-based amine and α, the reaction of β ethylene linkage unsaturated carboxylic acid forms the polyamide-based amine that replaces, then, under the condition that is enough to form branched polyamide base amine with pendant amine part (pendant amine moiety), the polyamide-based amine that makes replacement with have secondary amine and/or primary amine polyamines partly and contact.Be enough to handle this branched polyamide base amine with epihalohydrin then forming on the branched polyamide base amine under the curable ammonium condition partly of side chain.

In polyamide-based amination ammonium, azetidine polymkeric substance most preferably.These polymkeric substance comprise the monomeric repeating unit that contains replacement or unsubstituted azetidine ring (that is the quaternary heterocycle that, contains nitrogen).The polymkeric substance of the type is sold with the form of water base ingredients.Exemplary product is to derive from Hercules Inc., Wilmington, and the KYMENE 557H of Delaware, its form with 12.5% aqueous solution is sold.

In addition, composition of the present invention can comprise the cationic polyamine/epihalohydrin affixture as resin or polymeric constituent, those that for example derive from Hercules, sell with trade mark KYMENE 736.Preferably sell at present with the active base fluid (actives basis solution) of 38wt% or the form of suspension.

About film forming latex polymer materials, can be selected from wide variety of materials, for example styrene-butadiene copolymer, acrylate resin, polyvinyl acetate base ester and similar material.Some latex materials that can buy comprise:

The name of article type

" Neocar " (Union Carbide) vinyl ester/acrylic acid or the like

" Res 3077 " (Rohm ﹠amp; Haas) vinyl-acetic ester/acrylic acid or the like

" Airflex " 500 (Air Products) vinyl-acetic ester/ethene

" Airflex 4514 (Air Products) vinylchlorid/acid amides terpolymer

Airflex 4500 (Air Products) vinylchlorid/acid amides terpolymer

Flexhane 620 (Air Products) urethane

Vinac884 (Air Products) vinyl-acetic ester

Dow 620(Dow) SBR

Airflex 4530 (Air Products) polyamide-based amine/EPI and ethene

Vinylchlorid

Can add tensio-active agent, softening agent and coalescing agent when needed to make latex suspension.In preferred mode, Kymene 557H product is added in Airflex 4530 products of purchase, and add extra deionization (DI) water, obtain latex emulsion.

The fluoro-acid that exists in the handled thing ingredients is water-soluble fluoro-acid or its mixture of IVB family metal.Fluorine zirconic acid H ₂ZrF ₆Be preferred at present, although also can mention H as example ₂TiF ₆Also can use the combination of these acid.

As mentioned above, phosphoric acid H ₃PO ₄With its salt also be the component of choosing wantonly.Term " phosphoric acid " refers to its acid and two kinds of forms of salt as used herein.

In aqueous treating composition, can also there be amino silane compounds.Because its effectiveness and value of purchase, (γ-APS) is desirable to use the gamma-amino propyl silane.But, also can mention other oxyalkylated aminoalkyl group silane, for example TSL 8330.Can consult United States Patent (USP) 6,203,854 obtain the inventory of oxyalkylated more completely aminoalkyl group silane.

Usually, the latex that obtains from suppliers and polyamide-based amine/epihalohydrin or cationic polyamine/epihalolhydrin resins are the form of the aqueous solution or suspension.Mix these products, then to wherein adding fluoro-acid, phosphoric acid and aminosilane and leniently stirring.The pH of treatment compositions is roughly about 2 to about 6 usually.

The suspension of dilution of preparation handled thing, this suspension comprises, in activeconstituents (on anactives basis):

0.01-80wt% polyamide-based amine/epihalolhydrin resins or cationic polyamine/epihalolhydrin resins

0.01-30wt% latex film forming polymkeric substance

The 0.01-30wt% fluoro-acid

0.01-30wt％H ₃PO ₄

The 0.05-10wt% aminosilane

Excess water (adding to 100%).

The composition that more preferably has following compositing range (weight meter).

0.01-30wt% polyamide-based amine/epihalolhydrin resins or cationic polyamine/epihalolhydrin resins

0.01-25wt% latex film forming polymkeric substance

The 0.01-10wt% fluoro-acid

0.01-10％H ₃PO ₄

The 0.05-10wt% aminosilane

Excess water (adding to 100%).

Required metallic surface for example Al or steel can contact with handled thing in the mode of spraying, dip-coating or roller coat.Drying treatment thing then, this metallic surface can prepare to be used for brushing or other application.

Use conversion coating weight that conversion of the present invention or Passivation Treatment thing obtain greater than about 1 milligram/square feet treat surface, more preferably weight is about 2-50 milligram/square feet.

Now, the preferred handled thing ingredients of using is:

Wt％

Cationic amine polymkeric substance/epihalohydrin affixture 15.28

(Kymene 736)

(Neocar 8.56 for vinyl ester/acrylic latex

2535)

γ-APS-aminosilane 1.00

Fluorine zirconic acid 1.71

Hydrofluotitanic acid 2.28

Phosphoric acid 6.37

Water (adding to 100%) surplus

For the purposes in the industrial application, use to comprise 3-100wt%, the working solution of the above-mentioned preferred ingredients of preferred 10-100wt% concentration contacts with required metallic surface.

Embodiment

Now will describe the present invention with the following Examples, this embodiment should regard the demonstration of certain embodiments of the invention as, and should not think the scope of the present invention that limited.

Embodiment 1-handled thing ingredients

A kind of test processing phenology matching agent " A " is the latex emulsion that comprises following component: a) polyamide-based amine/epihalolhydrin resins of 75wt%-KYMENE 557H-Hercules Inc.-(12.5% activeconstituents); B) the Airflex 4530 ethene vinylchlorid emulsions of 11.1wt%; (about 50% activeconstituents); And c) balance of deionized water.The phosphoric acid and the fluoro-acid of the variable content shown in this base conditioning thing, adding.

Processing order

Be prepared as follows the test panel of embodiment: the aqueous solution with basic surface promoting agent product 3% sprays and cleaning G70/70 electro-galvanized steel test panel (available from ACT Laboratories), then with the flushing of DI water, be coated with by spin coating with test processes thing ingredients again, then force dry air.The single coating polyester coating brushing of black of the plate that will handle then.The plate of brushing is used oven drying under 650 temperature, in the time of about 58 seconds, reach 450 of peak value metal temperatures (peak metaltemperature).The build that is coated with brush board is about 0.7-0.8mil., and pencil hardness is 3H, and MEK comes and goes and cleans (double rub) is 100+.

Obtain following handled thing ingredients and test.Permatreat  1500 is the cleaning pre-treatment things that do not contain chromium available from GE Betz.

Sample	Explanation
		1	6.8wt％“A”；1.0wt％H 2ZrF 6(45% activeconstituents); Excess water
2	6.8wt％“A”；1.0wt％H 2ZrF 6(45% activeconstituents); 1.0wt% phosphoric acid; Excess water
		3	6.8wt％“A”；1.0wt％H 2ZrF 6(45% activeconstituents); 2.0wt% phosphoric acid; Excess water
4	6.8wt％“A”；1.0wt％H 2ZrF 6(45% activeconstituents); 3.0wt% phosphoric acid; Excess water
		5	2.0wt% phosphoric acid, 1.0wt%H 2ZrF 6(45% activeconstituents); Excess water
6	10wt％Permatreat1500
		7	Prior art 15wt% does not contain the handled thing of chromium

Then, the test panel of brushing and handling according to following test procedure test:

A. draw lattice (Cross Hatch)-illustrate from tendency by the regional unsticking (disadhere) between the adjacent line that separates of coating.Carry out this test (grade is 0B to 5B, wherein 5B the best) according to ASTM D3359.

B.T-bending-the tendency (wherein 0T the best) of coating unsticking from crooked 180 ° metal is described is measured according to ASTM D4145-83.

C. reverse side impact-illustrates the tendency of coating unsticking from the metal that is out of shape because of the known momentum impact on the test surfaces opposition side, measures according to ASTM D2794.

D.MEK clean-illustrates that whether coating suitably solidifies, and measures according to National Coil Coaters ' Association (NCCA) method II-18.

E.NSS-carries out neutral salt spray test according to ASTM B-117, and according to ASTMD-1654 rate (10=the best).

The results are shown in table 1 and 2.

Table 1 physical testing data

Sample	Draw lattice tests (ASTM D3359)	T-crooked test (ASTM D4145-83)	Reverse side Impact Test (in/lb, ASTM D2794)	MEK cleans (NCCA 11-18)
					1	5B	0T	160	100+
2	5B	0T	160	100+
					3	5B	0T	160	100+
4	5B	4T	160	100+
					5	5B	0T	160	100+
6	5B	0T	160	100+
					7	5B	0T	160	100+

Table 2 neutral salt spray test data are according to the grade (10=the best) of ASTM D1654 identification plate

Sample	72 hours		168 hours		240 hours		336 hours		500 hours
												Line	The zone	Line	The zone	Line	The zone	Line	The zone	Line	The zone
1	7	8	5	8	4	7	4	7	1	-
											2	9	8	6	8	7	8	5	6	6	4
3	9	9	9	9	8	9	8	9	8	9
											4	9	9	9	9	8	9	8	8	7	8
5	9	9	9	9	8	9	7	9	7	9
											6	9	9	9	9	8	9	8	8	7	8
7	8	8	7	7	6	8	5	8	4	6

Embodiment 2

Improve the ingredients " A " of embodiment 1 as the latex component by replacing Union Carbide ' s Neocar 2535 vinyl/acrylate.Test ingredients with gained is called " B " below.

The ingredients of various handled things and effectiveness result (table 3) are as follows:

Sample	Explanation
		8	6.8wt％“B”；1.0wt％H 2ZrF 6(45% activeconstituents); 2.0wt% phosphoric acid; PH=2.44
9	10wt％Permatreat1500
		10	Prior art 15wt% does not contain the handled thing of chromium

Table 3.

Sample	T-crooked test (ASTM D4145-83)	Reverse side Impact Test (in/lb, ASTM D2794)	Draw lattice tests (ASTM D3359)	MEK cleans (NCCA 11-18)	24 hours neutral salt spray tests (ASTM D1654) *	500 hours neutral salt spray tests (ASTM D1654) *
							8	1T	160	5B	100+	9/8，9/9	8/9，9/9
9	0T	160	5B	100+	10/9，10/9	9/9，9/9
							10	1T	160	5B	100+	5/8，5/8	3/4，3/6

^*NSS result is the grade in line (scribe)/zone (field), 10=the best

Result in the table 2 confirms and the irrigation comparability result who does not contain chromium.

Embodiment 3

The another kind of novel pre-treatment thing that does not contain chromium as described below has the ingredients of following concentration and uses with process metal surfaces under different diluted state.The diluted state of listing below is used for the laboratory purposes, and should higher (concentration is 10-100%) in actual field is used.

Sample	Explanation
		11	5.0％v/v C
12	7.0％v/v C
		13	10.0％v/v C
14	12.0％v/v C
		15	15.0％v/v C
16	10.0％ v/v Permatreat1500

Ingredients " C " wt%

Polymeric amide/table chloro-hydrin(e) resin 13.4-(the active one-tenth of Kymene 557H-Hercules-12.5%

Divide)

Vinyl ester/acrylate latex 5.7 (Union Carbide-Neocar2535-53% activeconstituents)

Deionized water 63.8

APS 1.0-(γ-An Jibingjisanyiyangjiguiwan)

45% fluorine zirconic acid 3.8

60% hydrofluotitanic acid 3.8

75% phosphoric acid 8.5

Ingredients and effect (table 4 and 5) are as follows:

Table 4 physical testing data

Sample	Draw lattice tests (ASTM D3359)	T-crooked test (ASTM D4145-83)	Pencil hardness test (ASTM D3363-92a)	MEK cleans (NCCA 11-18)
					11	5B	0T	H	100+
12	5B	0T	H	100+
					13	5B	0T	H	100+
14	5B	0T	F	100+
					15	5B	0T	H	100+
16	5B	0T	H	100+

Table 5 neutral salt spray test data are according to the grade (10=the best) of ASTM D1654 identification plate

Sample	Explanation	240 hours		500 hours
						Line	The zone	Line	The zone
		11	5.0％v/v C	6	10					5	9
12	7.0％v/v C					7	10	5	10
		13	10.0％v/v C	7	10					6	9
14	12.0％v/v C					7	9	5	10
		15	15.0％v/v C	7	10					6	9
16	10.0％ v/v Permatreat1500					8	10	5	9

Data acknowledgement in the table 5 with the handled thing that does not contain chromium (sample 16) comparability result.

Embodiment 4

Following handled thing has the ingredients of following concentration and uses with process metal surfaces under different diluted state.

Ingredients D Wt%

Polymeric amide amine/table chloro-hydrin(e) resin 2.25 (Kymene 557H Hercules)

60% fluoro-acid 7.50

Deionized water 90.25

Ingredients and effectiveness result (table 6) are as follows:

Sample	Explanation
		17	15.0％v/v D
18	10.0%v/v does not contain the handled thing of chromium, prior art
		19	15.0%v/v does not contain the handled thing of chromium, prior art
20	10.0％v/v Permatreat1500

Table 6Tinius-Olsen cup (cup) data are according to ASTM D2794-93 classification convex surface (dome) (10=the best)

Sample	The test of Tinius-Olsen cup
		17	10
18	4L
		19	5L
20	10

The device that is used for this test is the Tinius-Olsen test machine, and its ball and diameter that has that diameter is a 7/8-inch (22mm) is the mould of 1-inch (25mm).Use Scotch#610 adhesive tape or equivalent, specimen is cut into the sample of 23/4 width.Test procedure and assessment are as follows:

Test procedure

Test at 77 ± 2 °F (25 ± 1 ℃).Should be before test in the described specimen of balance under the uniform temp.

Specimen is inserted in the latasuture of Tinius-Olsen machine, the coat side that need relate to up.Clockwise rotate the top handle with the fixing test sample.In vision slit, place the scale card micrometer and be adjusted to zero.

Usually the wheel that rotates this machine one side in a clockwise direction is up to reaching the distortion that needs or metal fracture taking place.Then, counterclockwise to rotate this wheel, rotate the top handle again and discharge sample to regain the ball of moulding.Use the Tinius-Olsen#610 band from deformed region, to remove unstable coating.

Assessment

Coating amount and the photograph standard substance (photographic standard) that to remove from sample that form, with adhesive tape sticking compare.According to carrying out ranking with 1 to 8 grade shown in this standard.The coating of removing from steel plate galvanized will be used to detect zinc.Spelter coating peels off from steel matrix sometimes under extreme deformation.

The film smoothness of the surface can influence the binding property of adhesive tape, has how many coatings to be removed from deformed region thereby can influence.

Embodiment 5

Ingredients E and F are prepared as follows.

E

Cationic amine polymkeric substance/table chloro-hydrin(e) affixture (a) 15.28

Vinyl ester/acrylic latex (b) 8.56

γ-APS-aminosilane 1.00

Fluorine zirconic acid 1.71

Hydrofluotitanic acid 2.28

Phosphoric acid 6.37

Water surplus

F

Cationic amine polymkeric substance/table chloro-hydrin(e) affixture (a) 7.64

Vinyl ester/acrylic latex (b) 4.56

γ-APS-aminosilane 1.00

Fluorine zirconic acid 1.71

Hydrofluotitanic acid 2.28

Phosphoric acid 6.37

Water surplus

Handling procedure

Ingredients E uses with process metal surfaces under different diluted state with F.Owing to be that non-brushing is used, therefore handled thing be applied to metal and test.The diluted state of listing below is used for the laboratory purposes, and should higher (concentration is 10-100%) in actual field is used

In following program, handle the galvanizing laboratory common plate of ACT Inc.:

Cleaning 3Betz KL 132,5s sprays, 20psi, 130

The flushing tap water, 5s

Dry freezing air, the laboratory moisture eliminator forced

Handle spin coating

Solidify 150 peak value metal temperatures

The sample explanation

21 solution E, 45%v/v

22 solution F, 45%v/v

23 prior aries, the chromium acrylic acid or the like passivation of purchase

The neutral salt spray test data the results are shown in table 7.

Table 7 neutral salt spray test data

Grade (corrosion of % white, 10=the best) according to ASTM D1654-92 identification plate

Sample	96 hours NSS	192 hours NSS
			21	2	2
22	2	5
			23	0	5

It should be understood that foregoing description of the present invention is not intention restriction and only be demonstration to the inventive features that limits in claims.

Claims (28)

1. one kind form to transform on the metallic surface or the method for passivating coating, comprise described metallic surface is contacted with aqueous treating composition, said composition comprises: (a) polyamide-based amine/epihalolhydrin resins or cationic polyamine/epihalolhydrin resins and (b) fluoro-acid of IVB family metal.

2. the process of claim 1 wherein that described aqueous treating composition also comprises (c) phosphoric acid.

3. the method for claim 2, wherein said aqueous treating composition also comprises (d) amino silane compounds.

4. the method for claim 2, it also comprises (e) film forming latex polymer.

5. the process of claim 1 wherein that described metallic surface is the metallic surface that applies zinc.

6. the process of claim 1 wherein that described metallic surface is a galvanized steel.

7. the process of claim 1 wherein that described metallic surface is an aluminium.

8. wherein there is described polyamide-based amine/epihalohydrin in the method for claim 4 and comprises crosslinked poly-azetidine polymkeric substance.

9. wherein there is described cationic polyamine/epihalolhydrin resins in the method for claim 4.

10. the process of claim 1 wherein that described treatment compositions is not chromate-containing.

11. the process of claim 1 wherein that described fluoro-acid (b) is H ₂ZrF ₆

12. the process of claim 1 wherein that described fluoro-acid (b) is H ₂TiF ₆

13. the method for claim 8, wherein said latex film forming component comprises vinylchlorid or vinyl ester/acrylate.

14. the method for claim 9, wherein said latex film forming component comprises vinylchlorid or vinyl ester/acrylate.

15. handle galvanized metal surfaces to form greater than the conversion of 1mg/ square feet or the method for passivating coating for one kind on described surface, described method comprises makes described galvanized metal surfaces contact with treatment compositions, described treatment compositions comprises latex film forming component, polyamide-based amine/epihalohydrin polymers or polyamines/epihalohydrin polymers, fluoro-acid, phosphoric acid and the aminosilane of IVB family metal, described method are included in it is contacted dry described metallic surface afterwards with described treatment compositions.

16. the method for claim 15, wherein said latex emulsion comprises vinylchlorid.

17. the method for claim 15, wherein said latex comprises vinyl ester/acrylate.

18. wherein there is polyamines/epihalohydrin polymers in the method for claim 15, and wherein said latex component comprises vinyl ester/acrylate.

19. be used for process metal surfaces form to transform or the composition of passivating coating thereon, described composition comprises polyamide-based amine/epihalolhydrin resins, or the fluoro-acid of cationic polyamine/epihalolhydrin resins, IV family metal, and water.

20. be used for process metal surfaces to form the composition of conversion or passivating coating thereon, described composition comprises:

0.01-80wt% polyamide-based amine/epihalolhydrin resins or cationic polyamine/epihalolhydrin resins

0.01-30wt% latex film forming polymkeric substance

The 0.01-30wt% fluoro-acid

0.01-30wt％ H ₃PO ₄

Excess water.

21. the composition of claim 20, it also comprises the aminosilane of the about 10wt% of about 0.01-.

22. wherein there is described cationic polyamine/epihalolhydrin resins in the composition of claim 20.

23. the composition of claim 22, wherein said latex film forming polymkeric substance is vinyl ester/acrylate.

24. wherein there is described polyamide-based amine/epihalohydrin polymers in the composition of claim 20.

25. the composition of claim 24, wherein said polyamide-based amine/epihalolhydrin resins are polyamide-based amination ammoniums.

26. the composition of claim 25, wherein said polyamide-based amination ammonium are crosslinked poly-azetidine polymkeric substance.

27. the composition of claim 24, wherein said latex film forming polymkeric substance are the polymkeric substance of vinyl-chloride-containing.

28. the composition of claim 20, it does not contain chromic salt.