CN103898496A - Novel silane nano trivalent chromium passivation solution and preparation method thereof - Google Patents
Novel silane nano trivalent chromium passivation solution and preparation method thereof Download PDFInfo
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- CN103898496A CN103898496A CN201210577216.5A CN201210577216A CN103898496A CN 103898496 A CN103898496 A CN 103898496A CN 201210577216 A CN201210577216 A CN 201210577216A CN 103898496 A CN103898496 A CN 103898496A
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Abstract
The invention relates to a novel silane nano trivalent chromium passivation solution and a preparation method thereof, and especially provides a technology and a preparation process of the passivation solution. The formula of the passivation solution is a complex formulation comprising the following raw materials: 3-10 parts of a trivalent chromium compound, 3-8 parts of a titanium zirconium (zirconium silicon) compound, 0-2 parts of zirconium oxide (hafnium dioxide), 0-3 parts of a silane coupling agent, 0-2 parts of a surface wetting agent, 1-5 parts of inorganic acid, 0-0.5 part of an antifoaming agent and 70-90 parts of water. The nano silane trivalent chromium passivation solution prepared by the preparation process has good stability, can be applied to surface treatment of steel, zinc and aluminum to form a nano oxide conversion coating on the workpiece to be processed, and can greatly enhance the uniformity and compactness of a passivation film, so as to improve corrosion resistance of the passivation film. The additional silane coupling agent can improve the adhesion of the film, and hardness and wear resistance of the passivation film, so as to increase the salt fog time of the passivation film.
Description
Technical field
the present invention relates to the passivating technique of field of metal surface treatment, be specifically related to formula of a kind of novel silane nanometer trivalent chromium deactivating liquid and preparation method thereof.
Background technology
chromic salt is the main component of common passivating solution in plating and surface treatment.The general passivating solution adopting is all selected hexavalent chromate at present, and the passivating solution subject matter of the type is that chromic toxicity is large, can be carcinogenic, can have a strong impact on human body and environment generation.Along with the enhancing of people's environmental consciousness, chromic application is restricted gradually.Because chromic toxicity is only 1% of sexavalent chrome toxicity, and the trivalent chromium of trace or the metal ion of needed by human, and trivalent chromium raw materials cost is relatively low, and therefore, trivalent chromium replaces sexavalent chrome, will greatly reduce the pollution of passivating solution to environment.Trivalent chromium has been applied to production as the main component of passivating solution, and has obtained good result.In first-generation trivalent chromium deactivating liquid, complexing agent is mainly fluorochemical, and its corrosion-resistant, is eliminated gradually.In s-generation trivalent chromium deactivating liquid, complexing agent is mainly selected organic complex, and adds other metal, and its erosion resistance improves greatly; But the passivation layer surface forming is coarse, have many pore defects, the luminance brightness that affects passivation layer with and corrosion resistance nature.Third generation trivalent chromium deactivating liquid, on the basis of the s-generation, directly adds hole sealing agent further to improve the erosion resistance of rete, convergence and practical application more.
in prior art, the hole sealing agent that passivating solution adds has acidic silicasol and nano silicon oxide etc.Chinese patent CN101158038A discloses in a kind of formula of passivating solution and has added diameter to be less than the acidic silicasol of 10 nanometers, and its impact of luminance brightness on passive film is less, can increase the hardness of passive film simultaneously.But silicon sol may react with trivalent chromium, generate the silicic acid chromium of indissoluble, may cause the homogeneity of passive film to reduce, affect its corrosion resistance.Master's thesis " the electrolytic galvanized sheet Cr of Zhang Jinsheng
3+
passivation and technical study " in the nano level silicon oxide that adds seal the space in passive film, but nano silicon oxide is dispersed in passivating solution as heterogeneous, its surface can be very high, easily reunites, and therefore can not well form uniform passivation layer.
Summary of the invention
the present invention seeks to be to overcome the shortcoming of prior art, provide a kind of film forming properties better, sticking power is stronger, the method for the better trivalent chromium deactivating liquid of preservative effect.
for achieving the above object, the technical solution used in the present invention is: in chromic passivating solution, add the better silane based compound of film forming properties, realize passivating process film forming more even, the passive film erosion resistance forming is higher, after the silane coupling agent film forming simultaneously adding, abrasion resistance properties also can be improved, and can extend the duration of service of passive film; Add after zirconium system, zirconium titanium sub-group compound, form nanometer amorphous state ZrO
2
novel conversion film, and have good sticking power between metallic surface and paint coating subsequently, the compactness of passive film is better, fine corrosion resistance.
the nanometer silane type trivalent chromium deactivating liquid the present invention relates to, is mainly applicable to iron and steel, zinc and aluminium surface treatment, on the workpiece of processing, forms nano ceramics conversion film, strengthens sticking power and the corrosion resistance nature of application.
nanometer silane trivalent chromium deactivating liquid component prescription involved in the present invention is: chromic compound 3-10 part, titanium zirconium (zirconium silicon system) compound 3-8 part, two zirconium oxychlorides (hafnium) 0-2 part, silane coupling agent 0-3 part, surface active agent 0-2 part, mineral acid 1-5 part, defoamer 0-0.5 part, water 70-90 part.
the present invention also provides a kind of preparation method of novel silane nanometer trivalent chromium deactivating liquid, comprises the following steps:
one, take in proportion various raw materials;
two, in its 2/3 water requirement, add titanium zirconium (zirconium silicon) compound taking, be stirred to dissolving;
three, in the solution making in step 2, add chromic compound, be stirred to dissolving;
four, in the solution making in step 3, add mineral acid, be stirred to dissolving;
five, in the solution making in step 4, add two zirconium oxychlorides (hafnium), be stirred to dissolving;
six, in the solution making in step 5, add silane coupling agent, be stirred to dissolving;
seven, in the solution making in step 6, add tensio-active agent, be stirred to dissolving;
eight, in the solution making in step 7, add defoamer, be stirred to dissolving;
nine, in the solution making in step 8, add the remaining water yield, be stirred to and be uniformly dissolved.
the present invention compared with prior art has following advantages:
1, in trivalent chromium deactivating liquid of the present invention, add titanium zirconium compounds, the nano-scale oxide conversion film of formation, can significantly promote homogeneity, the compactness of passive film, and then improves its corrosion resistance nature;
after the silane coupling agent film forming of 2, adding in the present invention, can improve the hardness of film sticking power, film, wear-resistant ability, and then increase the passivating solution salt fog time;
3,, in the present invention's passivating solution used, containing a small amount of trivalent chromium compound, greatly reduce the harm of chromium ion to environment.
Embodiment
a kind of novel silane nanometer trivalent chromium deactivating liquid, its formula consists of: chromic compound 3-10 part, titanium zirconium (zirconium silicon system) compound 3-8 part, two zirconium oxychlorides (hafnium) 0-2 part, silane coupling agent 0-3 part, surface active agent 0-2 part, mineral acid 1-5 part, defoamer 0-0.5 part, water 70-90 part.
the best composition (massfraction) of this nanometer silane trivalent chromium deactivating liquid is: chromic compound 3-5 part, titanium zirconium (zirconium silicon system) compound 3-5 part, two zirconium oxychlorides (titanium) 0-1 part, silane coupling agent 0-1 part, surface active agent 0-1 part, mineral acid 1-3 part, defoamer 0-0.3 part, water 85-90 part.
trivalent chromium compound of the present invention can be one or more in chromium sulphate, chromium nitrate, chromium trifluoride, chromium trichloride, chromium sesquioxide etc.; Described titanium zirconium (zirconium silicon system) compound can be one or more in fluorine zirconic acid, hydrofluotitanic acid, silicofluoric acid, ammonium fluozirconate, potassium fluozirconate, sodium fluozirconate, potassium fluotitanate, titanium sodium fluoride, ammonium silicofluoride, Sodium Silicofluoride, potassium silicofluoride etc.; Described silane coupling agent can be γ-aminopropyl triethoxysilane KH550, γ-glycidoxypropyltrimewasxysilane KH560, γ-methacryloxypropyl trimethoxy silane KH570, acrylic propyl trimethoxy silicane KBM-5103, one or more of the inside such as vinyltriethoxysilane KBE-1003; One or more in one or more in described surface active agent fatty alcohol-polyoxyethylene ether, polyoxyethylene glycol, alkylphenol polyoxyethylene, sodium lauryl sulphate, sodium laurylsulfonate, Sodium dodecylbenzene sulfonate, Dodecyl trimethyl ammonium chloride, dodecyl dimethyl benzyl ammonium bromide etc. etc.; Described mineral acid can be one or more in nitric acid, hydrochloric acid, phosphoric acid, sulfuric acid, hydrofluoric acid, Hydrogen bromide etc.; Described defoamer can be one or more in mineral oil defoaming agent, silicon-type defoamer, polyethers defoamer etc.
the method of preparing novel nano silane type trivalent chromium deactivating liquid is as follows:
one, take in proportion various raw materials;
two, in its 2/3 water requirement, add titanium zirconium (zirconium silicon) compound taking, be stirred to dissolving;
three, in the solution making in step 2, add chromic compound, be stirred to dissolving;
four, in the solution making in step 3, add mineral acid, be stirred to dissolving;
five, in the solution making in step 4, add two zirconium oxychlorides (hafnium), be stirred to dissolving;
six, in the solution making in step 5, add silane coupling agent, be stirred to dissolving;
seven, in the solution making in step 6, add tensio-active agent, be stirred to dissolving;
eight, in the solution making in step 7, add defoamer, be stirred to dissolving;
nine, in the solution making in step 8, add the remaining water yield, be stirred to and be uniformly dissolved.
for the ease of being familiar with the preparation of such nanometer silane trivalent chromium deactivating liquid, now describe the present invention in conjunction with the embodiments:
embodiment 1
a preparation method for nanometer silane trivalent chromium deactivating liquid, its step is as follows:
1) take 3 parts of chromium sulphates, 3 parts of fluorine zirconic acids, 1.5 parts of sodium fluozirconates, two 0.3 part of zirconium oxychloride, 0.5 part of KH550,0.3 part of ethoxylated dodecyl alcohol, 2 parts, nitric acid, 1 part of hydrochloric acid, 0.1 part of silicone antifoam agent, 88.3 parts, water;
2) in 50 parts of water, add 3 parts of fluorine zirconic acids to be stirred to abundant dissolving;
3) in step 2, add 1.5 parts of sodium fluozirconates to be stirred to abundant dissolving;
4) in step 3, add 3 parts of chromium sulphates to be stirred to abundant dissolving;
5) in step 4, add 2 parts of nitric acid, 1 part of hydrochloric acid to be stirred to dissolving;
6) in step 5, add 0.3 part of two zirconium oxychloride to be stirred to abundant dissolving;
7) in step 6, add 0.5 part of KH550 to be stirred to abundant dissolving;
8) in step 7, add the ethoxylated dodecyl alcohol of 0.3 part to be stirred to dissolving;
9) in step 8, add the silicone antifoam agent of 0.1 part to be stirred to dissolving
10) in step 9, adding 38.3 parts of water to be stirred to mixes.
embodiment 2
a preparation method for nanometer silane trivalent chromium deactivating liquid, its step is as follows:
1) take 5 parts of chromium trifluorides, 4 parts of fluorine zirconic acids, 3 parts of ammonium silicofluorides, two 0.5 part of zirconium oxychloride, 0.5 part of KH560,1 part, nitric acid, 0.5 part of phosphoric acid, 85.5 parts, water;
2) in 50 parts of water, add 4 parts of fluorine zirconic acids to be stirred to abundant dissolving;
3) in step 2, add 3 parts of ammonium silicofluorides to be stirred to abundant dissolving;
4) in step 3, add 5 parts of chromium trifluorides to be stirred to abundant dissolving;
5) in step 4, add 1 part of nitric acid, 0.5 part of phosphoric acid to be stirred to dissolving;
6) in step 5, add 0.5 part of two zirconium oxychloride to be stirred to abundant dissolving;
7) in step 6, add 0.5 part of KH560 to be stirred to abundant dissolving;
8) in step 7, adding 35.5 parts of water to be stirred to mixes.
embodiment 3
a preparation method for nanometer silane trivalent chromium deactivating liquid, its step is as follows:
1) take 6 parts of chromium nitrates, 2 parts of silicofluoric acid, 3 parts of Sodium Silicofluorides, 0.3 part of dioxy hafnium chloride, 1 part of KH550,3 parts, nitric acid, 1 part, sulfuric acid, 0.5 part of polyoxyethylene glycol, 83.2 parts, water;
2) in 50 parts of water, add 2 parts of silicofluoric acid to be stirred to abundant dissolving;
3) in step 2, add 3 parts of Sodium Silicofluorides to be stirred to abundant dissolving;
4) in step 3, add 6 parts of chromium nitrates to be stirred to abundant dissolving;
5) in step 4, add 3 parts of nitric acid, 1 part of sulfuric acid to be stirred to dissolving;
6) in step 5, add 0.3 part of two zirconium oxychloride to be stirred to abundant dissolving;
7) in step 6, add 1 part of KH550 to be stirred to abundant dissolving;
8) in step 7, add 0.5 part of polyoxyethylene glycol to be stirred to abundant dissolving
9) in step 8, adding 33.2 parts of water to be stirred to mixes.
Claims (2)
1. a novel silane nanometer trivalent chromium deactivating liquid, it is characterized in that, comprising that following raw material is composite forms: chromic compound 3-10 part, titanium zirconium (zirconium silicon) compound 3-8 part, two zirconium oxychlorides (hafnium) 0-2 part, silane coupling agent 0-3 part, surface active agent 0-2 part, mineral acid 1-5 part, defoamer 0-0.5 part, water 70-90 part.
2. a preparation method for novel silane nanometer trivalent chromium deactivating liquid, is characterized in that, comprises the following steps:
One, take in proportion various raw materials;
Two, in its 2/3 water requirement, add the titanium zirconium compounds taking, be stirred to dissolving;
Three, in the solution making in step 2, add chromic compound, be stirred to dissolving;
Four, in the solution making in step 3, add mineral acid, be stirred to dissolving;
Five, in the solution making in step 4, add two zirconium oxychlorides (hafnium), be stirred to dissolving;
Six, in the solution making in step 5, add silane coupling agent, be stirred to dissolving;
Seven, in the solution making in step 6, add tensio-active agent, be stirred to dissolving;
Eight, in the solution making in step 7, add defoamer, be stirred to dissolving;
Nine, in the solution making in step 8, add the remaining water yield, be stirred to and be uniformly dissolved.
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| CN104233252A (en) * | 2014-09-16 | 2014-12-24 | 南京华锐化工有限公司 | Novel room-temperature non-phosphorus coating agent |
| CN104894545A (en) * | 2015-04-28 | 2015-09-09 | 常州市春雷浩宇化工有限公司 | Silane ceramization agent and preparation method thereof |
| CN106048514A (en) * | 2016-06-27 | 2016-10-26 | 滁州帝邦科技有限公司 | Preparing method for wear-resisting steel used for water-cooling nozzle |
| CN107236948A (en) * | 2017-06-07 | 2017-10-10 | 广州传福化学技术有限公司 | It is a kind of to suppress the passivator that zinc coating trivalent chromium is oxidized to Cr VI |
| CN108004532A (en) * | 2017-12-20 | 2018-05-08 | 苏州禾川化学技术服务有限公司 | A kind of self-styled closed form trivalent chromium bright blue passivator |
| CN108642482A (en) * | 2018-07-03 | 2018-10-12 | 苏州大韩化工有限公司 | A kind of chromium-free passivation liquid and preparation method thereof |
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| CN110760832A (en) * | 2019-12-05 | 2020-02-07 | 佛山市南海高益美环保实业有限公司 | Trivalent chromium cobalt-free color passivator with high corrosion resistance for electro-galvanized layer |
| CN112663037A (en) * | 2020-12-04 | 2021-04-16 | 佛山市顺德区美硕金属表面技术有限公司 | Vitrification agent, preparation method and application thereof |
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| CN101724836A (en) * | 2009-10-23 | 2010-06-09 | 启东市合成化工厂有限公司 | Passivating treating agent for environment-friendly galvanized steel sheets |
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| CN104233252B (en) * | 2014-09-16 | 2016-08-24 | 南京华锐化工有限公司 | A kind of room temperature non-phosphate film agent |
| CN104894545A (en) * | 2015-04-28 | 2015-09-09 | 常州市春雷浩宇化工有限公司 | Silane ceramization agent and preparation method thereof |
| CN106048514A (en) * | 2016-06-27 | 2016-10-26 | 滁州帝邦科技有限公司 | Preparing method for wear-resisting steel used for water-cooling nozzle |
| CN107236948A (en) * | 2017-06-07 | 2017-10-10 | 广州传福化学技术有限公司 | It is a kind of to suppress the passivator that zinc coating trivalent chromium is oxidized to Cr VI |
| WO2019006616A1 (en) * | 2017-07-03 | 2019-01-10 | 深圳市宏昌发科技有限公司 | Passivator, metal workpiece and method of surface passivation therefor |
| CN110809634A (en) * | 2017-07-03 | 2020-02-18 | 深圳市宏昌发科技有限公司 | Passivating agent, metal workpiece and surface passivation method thereof |
| CN108004532A (en) * | 2017-12-20 | 2018-05-08 | 苏州禾川化学技术服务有限公司 | A kind of self-styled closed form trivalent chromium bright blue passivator |
| CN108642482A (en) * | 2018-07-03 | 2018-10-12 | 苏州大韩化工有限公司 | A kind of chromium-free passivation liquid and preparation method thereof |
| CN110760832A (en) * | 2019-12-05 | 2020-02-07 | 佛山市南海高益美环保实业有限公司 | Trivalent chromium cobalt-free color passivator with high corrosion resistance for electro-galvanized layer |
| CN112663037A (en) * | 2020-12-04 | 2021-04-16 | 佛山市顺德区美硕金属表面技术有限公司 | Vitrification agent, preparation method and application thereof |
| CN114016692A (en) * | 2021-11-09 | 2022-02-08 | 晋江市新思维环保科技有限公司 | Honeycomb aluminum plate based on hot press molding and preparation process thereof |
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