CN101082130A - Production technique of environmental protection color coating steel plate - Google Patents
Production technique of environmental protection color coating steel plate Download PDFInfo
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- CN101082130A CN101082130A CN 200610027073 CN200610027073A CN101082130A CN 101082130 A CN101082130 A CN 101082130A CN 200610027073 CN200610027073 CN 200610027073 CN 200610027073 A CN200610027073 A CN 200610027073A CN 101082130 A CN101082130 A CN 101082130A
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Abstract
The present invention relates to color painted steel plate, and is especially process of producing environment friendly color painted steel plate. The production process includes the steps of: unwinding steel plate coil, joining, degreasing, pre-treatment through spraying or roller coating to deactivate, painting primer, baking, cooling, applying surface paint, baking, cooling and winding. The painted primer is polyurethane or polyester primer containing no chrome yellow, and the applied surface paint is environment friendly paint containing no Cr, Cd, Pb, etc.
Description
Technical field: the present invention relates to a kind of color painted steel plate, particularly a kind of production technique of environmental protection color coating steel plate.
Background technology: color coated steel sheet is mainly used in buildings roof, exterior wall etc., begins to be applied on the household appliances seventies from twentieth century.2004, the color coated steel sheet that the whole world is used for household electrical appliances reached 2,140,000 tons, accounts for 12.3% of global color coating product population.China is the major country of production man of household appliances, and world-famous brand all has the production base in the continent, and the product of many household appliances enterprises is found a good sale in the America and Europe, but according to incomplete statistics, 150,000 tons/year of the domestic color coating product less thaies that is used for household electrical appliances.European Union limits the household appliances that enter Europe limit council's instruction (ROHS instruction) promulgation of using some objectionable impurities in electrical equipment and electronics after.In order to satisfy the ROHS command request, domestic each relevant industries active research counte-rplan and measure.The color coating product application also must be satisfied the environmentfriendly products requirement in household electric appliances.Along with closing on that european union directive is carried out, increasing household appliances user proposes the environmental protection demand of color coating product.
Present production color coated steel sheet all contains objectionable impurities and can not satisfy the demand (see Table 1) of European Union to environmentfriendly products.These objectionable impuritiess come from the processes such as substrate, pre-treatment, priming paint and finish paint coating in the color coating process of producing product respectively.
Harmful substance contents in the non-environmentfriendly products coated layer of table 1
| Numbering | Coating producer | Type of substrate | Steel grade | Specification | The coating kind | Cd ppm | Pb (ppm) | Cr 6+ ppm |
| 1 | China of shaking | Pot galvanize | Tst01 | 0.6×1000 | Polyester | ＜5 | 151 | 2277 |
| 2 | Bei Ge | Pot galvanize | Tst01 | 0.8×1200 | PVDF | ＜5 | 3399 | 11288 |
| 3 | Bei Ge | Pot galvanize | TS350GD | 0.5×1000 | PVDF | |||
| 4 | Wei Shibai | Pot galvanize | TS280GD | 0.5×1000 | PVDF | ＜5 | 25 | 10057 |
| 5 | China of shaking | Pot galvanize | Tst01 | 0.6×1000 | Polyester | ＜5 | 177 | |
| 6 | Bei Ge | Pot galvanize | TDC51 | 0.8×1000 | HDP | |||
| 7 | Bei Ge | Pot galvanize | Tst01 | 0.4×1000 | HDP | |||
| 8 | Bei Ge | Pot galvanize | TS280GD | 0.6×1000 | PVDF | |||
| 9 | Bei Ge | Pot galvanize | TS350GD | 0.5×1098 | PVDF | ＜5 | 3075 | |
| 10 | AKCO | Pot galvanize | TDC51 | 0.6×1000 | Polyester | ＜5 | 90 | 3402 |
| 11 | Bei Ge | Electro-galvanizing | TSECC | 0.8×1100 | Polyester | |||
| 12 | Bei Ge | Electro-galvanizing | TSECCB | 0.6×1100 | Polyester | ＜5 | 2769 | 482 |
The color coated steel sheet structure mainly comprises substrate (cold-reduced sheet and coating), is coated with chemical conversion layer, priming paint and finish paint successively on the substrate two sides.In the zinc pot, add plumbous in some zinc-plated unit productions at present to obtain to have the product of certain zinc flower.As improving substrate and coating bonding force and corrosion proof pretreatment technology, the general harmful elements such as containing sexavalent chrome that adopts in its treatment solution.The pretreatment technology of color coating unit has three kinds: phosphatization, immersion and roller coat formula, and the passivation procedure in the phosphatization mode treatment process contains sexavalent chrome; The immersion pretreatment technology has comprised alkali cleaning, combined oxidation, passivation, contains deleterious sexavalent chrome in its passivation technology (spray mode); The roller coat pretreatment technology comprises alkali cleaning, passivation, wherein contains sexavalent chrome in the passivation technology (roll coating model).Therefore developing color coating environmental protection steel plate must change existing pre-treatment treatment solution and technology.The paint base system that general color coating product uses all contains the chrome pigment that contains that improves corrosion resisting property, may contain harmful elements such as lead, cadmium because of mixing color in some finish paint, so the environmental protection color coating steel plate exploitation must employing not contain the coating variety that is harmful to element yet.In a word, produce the color coated steel sheet of compliance with environmental protection requirements, must change the selection of existing substrate, pre-treatment and coating, corresponding production technique also changes thereupon.And these changes are still to produce the color coated steel sheet that meets customer requirements is target.
Summary of the invention: the purpose of this invention is to provide a kind of production technique of environmental protection color coating steel plate, mainly solve the technical problem that contains harmful elements such as lead, cadmium, sexivalent chromium in the coating that has color coated steel sheet now.Technical scheme of the present invention is: a kind of production technique of environmental protection color coating steel plate, its processing step is followed successively by: the substrate uncoiling, sew up, degreasing, pre-treatment, prime, toast, cooling, overpainting, baking, cool off and batch.
Described pre-treatment is a kind of in spray mode and the roller coat passivation mode, preprocessing solution is a passivating dip, form the pre-treatment film at substrate surface after the pre-treatment, it is characterized in that described substrate selects to meet the electro-galvanizing or the hot-dip galvanizing sheet steel of ROHS command request, when the spray mode is adopted in pre-treatment, the speed of unit be 60-100 rice/minute, preprocessing solution concentration is 0.4～0.6g/l, and the pH of preprocessing solution is 2.2～2.5, and Ti content is 3～9mg/m in the control pre-treatment film
2Between, temperature is a normal temperature during spray.
When adopting roller coat passivation mode, the speed of unit is 60～100 meters/minute, application roll speed is 110% of unit speed, carrying roller speed is 50% of unit speed, application roll and band steel pressure are 2000～2500Mpa, carrying roller and application roll pressure are 2500～3000MPa, and Ti content is 5～8mg/m in the control pre-treatment film
2Between.
The priming paint that applies is not for containing the white primer that chrome yellow etc. contains chrome pigment, and the priming paint kind is polyester or urethane type, can select for use the China of shaking to make the CH373 of lacquer factory, or the DE-216-98301 of BECKER company, or the CP21 of BASF AG etc.Finish paint is not for containing the environmental protection coating material of chromium, cadmium, lead etc., can select for use the China of shaking to make the environmental protection finish paint (according to the color difference, trade mark difference) that lacquer factory or BECKER company provide.
The invention has the beneficial effects as follows: the pre-treatment film heavily is the key of environmental protection color coating product processes control, the variation of pretreatment technology is a ultimate aim with it all, only when film is heavily controlled, control Ti content in the pre-treatment film, the pre-treatment film properties that obtains in scope is only optimum.The control of strength of solution is very important in this technology, in concentration range and cooperate temperature, reaction times (unit speed) etc., could guarantee to obtain the content of Ti in the pre-treatment film within scope.Simultaneously, the control of pH also is very crucial, reaction times prolongation along with solution and steel plate, the solution middle acid substance can be consumed gradually, pH value of solution can raise gradually, the continuation that is unfavorable for the pre-treatment film when exceeding 2.5 forms, so needs constantly to replenish fresh solution in the production process, keeps concentration and pH value.The control of unit speed mainly is to weigh scope in order to stablize the pre-treatment film, and cooperates acquisition good coating performance and surface quality with coating process.Can change according to the appointed condition of particular rack.In the selection and the environmental protection color coating production technique of aspects such as coating, pre-treatment and substrate, can produce the environmental protection color coating product that meets customer need and satisfy the ROHS instruction according to the present invention.
Embodiment: embodiment 1: the production technique of environmental protection color coating steel plate, its processing step is followed successively by: the substrate uncoiling, sew up, degreasing, pre-treatment, prime, toast, cooling, overpainting, baking, cool off and batch.Substrate is selected the unleaded hot dip galvanizing substrate that meets the ROHS command request for use, and the spray-type pre-treatment is adopted in pre-treatment, and preprocessing solution is selected Henkel chemical company limited 350 environmental protection passivating dips for use, and technology is as follows:
| Unit speed | Temperature | Concentration | PH |
| 60m/min | Normal temperature | 0.4-0.5g/l | 2.2-2.5 |
Select for use the China of shaking to make lacquer factory's environment-friendly polyurethane priming paint (CH373) and environmental protection finish paint (Tianshan Mountains is white).The performance index that obtain environmental protection color coating steel plate see Table 2, and environmental protection tests the results are shown in Table 3.
Embodiment 2, and the spray-type pre-treatment is adopted in pre-treatment, and substrate is selected the electro-galvanizing substrate that meets the ROHS command request for use, and technology is as follows:
| Unit speed | Temperature | Concentration | PH |
| 80m/min | Normal temperature | 0.5-0.6g/l | 2.2-2.5 |
The DE-216-98301 that selects BECKER company for use is as priming paint, and finish paint is selected BECKER company environmental protection finish paint for use.All the other are identical with embodiment 1.
Embodiment 3, and the spray-type pre-treatment is adopted in pre-treatment, and unit speed is 100 meters/minute, and preprocessing solution concentration is 0.5g/l, and the CP21 that selects BASF AG for use is as priming paint, and finish paint is made lacquer factory's environmental protection finish paint (Tianshan Mountains is white) for the China of shaking.All the other are identical with embodiment 1.
Embodiment 4, and roller coat passivation mode is adopted in pre-treatment, and pretreatment fluid is selected the TP10478A+TP10478B of Kai Miteer for use, and technology is as follows: the A roller is an application roll, and the P roller is a carrying roller.
| Unit speed | A roller speed of relative movement % | P roller speed of relative movement % | A/P pressure MPa |
| 60m/min | 110 | 50 | 3000 |
All the other are identical with embodiment 1.
Embodiment 5, and roller coat passivation mode is adopted in pre-treatment, and pretreatment fluid is selected the PT1021B of BETZ company for use, and technology is as follows:
| Unit speed | A roller speed of relative movement % | P roller speed of relative movement % | A/P pressure MPa |
| 80m/min | 110 | 50 | 2800 |
All the other are identical with embodiment 1.
Embodiment 6, and roller coat passivation mode is adopted in pre-treatment, and pretreatment fluid is selected 1455 of Henkel chemical company limited for use.Technology is as follows:
| Unit speed | A roller speed of relative movement % | P roller speed of relative movement % | A/P pressure MPa |
| 100m/min | 110 | 50 | 2600 |
All the other are identical with embodiment 1.
Table 2 environmental protection color coating steel plate performance index
| Numbering | Project | Test method | Product requirement | Nippon Steel | The river fine jade | The present invention |
| 1 | The substrate kind | SGCD2 or suitable | SGCD2 or suitable | SGCD2 or suitable | SGCD2 or suitable | |
| 2 | Zinc layer weight | 40/40 or 60/60 gram/square metre | 40/40g/m 2 | 40/40g/m 2 | 60/60g/m 2 | |
| 3 | Outward appearance | Visual JIs K5400 7.1 | Inclusion-free, bubble etc. hinder the defective of use | Well | Well | Well |
| 4 | Thickness | The damage type film thickness gauge | On/down | 23/6μm | 25/7μm | 25/12μm |
| 5 | Aberration | Visual | With reference to model | Qualified | Qualified | Qualified |
| 6 | Gloss | JIS K5400 7.6 | With reference to model | 70％ | 73％ | 69％ |
| 7 | Sticking power | JIS | 100/100 | 100/100 | 100/100 | 100/100 |
| 8 | Pencil hardness | JIS K5400 8.4 (Mitsubishi's pencil) | More than the H | H | H | 2H |
| 9 | Impact resistance | JIS K5400 8.3.2 1/2 " * 500 grams | The flawless of filming | 50cm(2.45J)OK | 50cm(2.45J)OK | 50cm(2.45J)OK |
| 10 | Crooked | 0℃2T | The visual flawless of filming | Do not have | Do not have | Do not have |
| Normal temperature 0T | Do not have | Do not have | Do not have | |||
| 11 | Cup is protruding | JIS K5400 8.2 | The flawless of filming | 7mmOK | 7mmOK | 7mmOK |
| 12 | Wet fastness | 40 ℃ * 98% (humidity) * 240 hour | It is no abnormal to film | Do not have | Do not have | Do not have |
| 13 | Solidity to corrosion | Salt-fog test 240 hours | Otch expands the erosion width | The 0-3 millimeter | The 0-3 millimeter | The 0-1 millimeter |
| End face expands the erosion width | The 0-5 millimeter | The 0-5 millimeter | The 0-5 millimeter | |||
| 14 | Weather resisteant | DEW test 120 hours | Aberration≤2.5 | 2.1 | 1.7 | 2.4 |
| Remaining gloss rate 〉=75% | 106％ | 84％ | 81％ | |||
| 15 | Anti-ly heat, pressurizing performance | Adopt 20mm width PET film phonograph seal, pressurization 4kg placed 2 hours under 60 ℃ of conditions | No sharp trace | Do not have | Do not have | Do not have |
| 16 | Scuff resistance | Forefinger and middle finger twine gauze in 50 cm range reciprocal for 10 times | There is not remaining vestige | Do not have | Do not have | Do not have |
Environmental protection tests of the present invention the results are shown in Table 3 (detecting through Shanghai SGS)
Table 3 color coated steel sheet environmental-protecting performance detected result
| Element | The ROHS instruction | The present invention |
| Plumbous (Pb) | ＜100ppm | ＜3ppm |
| Cadmium (Cd) | ＜100ppm | Do not detect |
| Sexavalent chrome (Cr6+) | Forbidding | Do not detect |
| Mercury (Hg) | Forbidding | Do not detect |
Claims (4)
1, a kind of production technique of environmental protection color coating steel plate, its processing step is followed successively by: the substrate uncoiling, sew up, degreasing, pre-treatment, prime, baking, cooling, overpainting, baking, the cooling and batch, described pre-treatment is a kind of in spray mode and the roller coat passivation mode, preprocessing solution is a passivating dip, form the pre-treatment film at substrate surface after the pre-treatment, it is characterized in that, described substrate selects to meet the electro-galvanizing or the hot-dip galvanizing sheet steel of ROHS command request, when the spray mode is adopted in pre-treatment, the speed of unit be 60-100 rice/minute, preprocessing solution concentration is 0.4～0.6g/l, and the pH of preprocessing solution is 2.2～2.5; When adopting roller coat passivation mode, the speed of unit is 60～100 meters/minute, application roll speed is 110% of unit speed, carrying roller speed is 50% of unit speed, application roll and band steel pressure are 2000～2500Mpa, carrying roller and application roll pressure are 2500～3000MPa, and the priming paint of coating is not for containing the polyester or the polyurethanes priming paint of chrome yellow, and finish paint is not for containing the environmental protection coating material of chromium, cadmium, lead etc.
2, the production technique of a kind of environmental protection color coating steel plate according to claim 1 is characterized in that, when the spray mode was adopted in pre-treatment, Ti content was 3～9mg/m in the control pre-treatment film
2Between.
3, the production technique of a kind of environmental protection color coating steel plate according to claim 1 is characterized in that, temperature is a normal temperature during spray.
4, the production technique of a kind of environmental protection color coating steel plate according to claim 1 is characterized in that, when roller coat passivation mode was adopted in pre-treatment, Ti content was 5～8mg/m in the control pre-treatment film
2Between.
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| CN101281395B (en) * | 2008-05-09 | 2011-07-06 | 东北大学 | Steel enterprise color coating machine unit production operation system optimization technological process |
| CN102168262A (en) * | 2011-04-12 | 2011-08-31 | 马鞍山钢铁股份有限公司 | Chromium-free passivation method of galvanized sheets |
| CN102431264A (en) * | 2011-09-20 | 2012-05-02 | 常熟华冶薄板有限公司 | Fireproof color-coated decorative steel plate and production method thereof |
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| CN109604336A (en) * | 2018-10-24 | 2019-04-12 | 首钢京唐钢铁联合有限责任公司 | Method and device for preparing hot-dip galvanized sheet |
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| CN101281395B (en) * | 2008-05-09 | 2011-07-06 | 东北大学 | Steel enterprise color coating machine unit production operation system optimization technological process |
| CN102168262A (en) * | 2011-04-12 | 2011-08-31 | 马鞍山钢铁股份有限公司 | Chromium-free passivation method of galvanized sheets |
| CN102168262B (en) * | 2011-04-12 | 2013-01-30 | 马鞍山钢铁股份有限公司 | Chromium-free passivation method of galvanized sheets |
| CN102431264A (en) * | 2011-09-20 | 2012-05-02 | 常熟华冶薄板有限公司 | Fireproof color-coated decorative steel plate and production method thereof |
| CN103028531B (en) * | 2011-09-30 | 2014-07-23 | 宝山钢铁股份有限公司 | Production method for thickening type half organic coating non-oriented silicon steel |
| CN103028531A (en) * | 2011-09-30 | 2013-04-10 | 宝山钢铁股份有限公司 | Production method for thickening type half organic coating non-oriented silicon steel |
| CN102698949A (en) * | 2012-05-10 | 2012-10-03 | 合肥海尔特种钢板研制开发有限公司 | Preparation method of vertical texture colorful board as well as colorful board manufactured by using preparation method |
| CN102698949B (en) * | 2012-05-10 | 2014-12-10 | 合肥海尔特种钢板研制开发有限公司 | Preparation method of vertical texture colorful board as well as colorful board manufactured by using preparation method |
| CN109604336A (en) * | 2018-10-24 | 2019-04-12 | 首钢京唐钢铁联合有限责任公司 | Method and device for preparing hot-dip galvanized sheet |
| CN112126938A (en) * | 2020-08-31 | 2020-12-25 | 首钢智新迁安电磁材料有限公司 | Method and device for controlling surface quality of strip steel |
| CN112126938B (en) * | 2020-08-31 | 2023-01-10 | 首钢智新迁安电磁材料有限公司 | Method and device for controlling surface quality of strip steel |
| CN114833053A (en) * | 2022-06-07 | 2022-08-02 | 武汉钢铁有限公司 | Color-coated sheet and preparation method thereof |
| CN115011186A (en) * | 2022-06-20 | 2022-09-06 | 马鞍山钢铁股份有限公司 | Environment-friendly passivation primer with high corrosion resistance and excellent adhesive force, preparation method thereof, environment-friendly economical building color-coated plate and production method thereof |
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