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Powder sales belie industrial decline
FOCUS ON P O W D E R C O AT I N G S A MONTHLY REPORT FROM SID HARRIS
POWDER SALES BELIE INDUSTRIAL DECLINE
MAY 2008 In this issue
TECHNICAL
2-3
Pretreatment processes for powder coated HRS
INDUSTRY NEWS
3-6
Architectural applications for liquid and powder fluoropolymer coatings ChinaCoat is the premier coatings event in Asia Cytec offers Crylcoat new generation resins Swan first at coatings show Akzo Nobel: economy has limited impact on Industrial Coatings in US
MARKETS
AN INTERNATIONAL NEWSLETTER MONITORING TECHNICAL AND COMMERCIAL DEVELOPMENTS IN POWDER COATINGS ISSN 1364–5439
6-8
Vietnam becoming boom zone for Southeast Asia paint Jotun with production plant in India Nanotech’s pulse quickens DSM announces investment
Popular media outlets seem to be convinced that the global markets are in free-fall and prophesy a “doom and gloom” scenario for 2008 and beyond. Their indicators are the current dismal reports of the international banking system representing a conglomeration of misguided and, in some notable cases avaricious, lending institutions. They are now realizing their past mistakes and the initial reaction is to drastically curb high risk loans, at least in the foreseeable future. I do not predict any major effect on the global economies if the banks do restrict their unbridled lending spree, and it may prove to be beneficial in the long term if the general public finally appreciate the necessity to live within their means. Escalating prices for energy and food will help to restore fiscal sanity. Industry should not be greatly affected by these adverse market conditions, and the 2007 results from a number of major powder producers tends to substantiate my belief that the coatings industry is gradually moving back into the level of profitability enjoyed in the years prior to 2005. In this issue, the results of 2007 sales of powder coating are reviewed in the annual statements of the larger global producers and these are growing at rates in excess of GNP, a sure sign that
manufacturing industries are experiencing healthy growth. Even in the US, where the economy is claimed to be declining, I have received reports that many powder producers are working twenty four hours a day to meet the current demand from US industry. Abstracted market reports from a number of European countries confirm powder growth rates are well above the average growth rates for liquid coatings. Additionally, the Green Movement grows in strength and adds impetus to powder preference! While powder coatings are almost the mandatory choice for protection of hot rolled steel used in many automotive, appliance and agricultural applications, it is understood that there is a need to clean and pre-treat the metal surface prior to coating in order to maximize the performance of the powder in terms of mechanical and chemical properties. In common with many established pretreatment processes, the conventional techniques of iron or zinc phosphate conversion coatings are arousing concerns related to toxicity and high running costs. An alternative system using a zirconium based nano-structured conversion coatings has the advantages of lower cost and environmental compliance. A paper by
POWDER COATINGS POWDER COATINGS POWDER COATINGS POWDER COATINGS
F O C U S researchers at the University of Ulster has compared these three options and their effect on corrosion protection, and the conclusions are abstracted in the technical section. At a recent meeting of the Powder Coatings Institute, the main topic reviewed was the potential for powder coating wooden surfaces. There has been considerable progress in adapting powder coatings for coating MDF board with both thermal and UV curable powder systems. The big challenge is the powder coating of natural wood surfaces for domestic furniture and this is an opportunity that I believe will be resolved by UV curable powder systems. A high volume, potential market! Sid Harris
TECHNICAL Pretreatment processes for powder coated HRS Powder coatings are well established for the protection of hot rolled steel components used in the automotive, agricultural and appliance industries where they offer good aesthetic, chemical and corrosion resistance qualities. The performance of any coating is influenced by the pretreatment given to the metal substrate prior to the application of the coating. An article by Tepe and Gunay of the University of Ulster examines the corrosive response of HRS after it had been exposed to various surface treatments, before powder coating. The behaviour of three conversion coatings: zinc phosphate; iron phosphate and zirconium based nano-structured conversion was studied. HRS is naturally covered with iron oxide scale and this was removed from the surface by mechanical and chemical processes prior to the application of the surface treatment and powder coating.
2
O N
POWDER
The various treated panels were subjected to the following tests to evaluate corrosion performance: adhesion tests, including crosshatch, pull-off and conical bending, SEM, XPS, salt spray and electro-chemical impedance studies were also performed. Surface preparation of metal surfaces involving cleaning and treatment with conversion coatings ensures good adhesion between the substrate and the coating and increases corrosion and blister resistance. The main pretreatments for steel are iron and zinc phosphate, and both types are widely used in industry. Their economy of phosphating, speed of operation and ability to provide excellent corrosion resistance, adhesion and lubricant properties has established their wide use, but high running costs and concerns about the toxicity and eutrophication effect of phosphating waste, has made it necessary for manufacturers to seek alternative cost-effective and environmentally friendly conversion coatings. The new pre-treatment methods are claimed to provide equivalent or superior performance to the conventional conversion phosphating methods. These nano-structured conversion coatings can be applied at a number of points in the pretreatment process. Many of these new products are based on zirconium and coating thicknesses are in the nano range compared to the micron levels of conventional conversion coatings. Typical coating thickness ranges from 10 to 25 nm. The iron scales formed on HRS are a mixture of iron oxides, lacking in uniformity and therefore offer no barrier protection. This loosely adherent layer is prone to chip and crack under impact and environmental conditions such as heat or humidity, and breaks in the film can promote electrochemical action causing the steel substrate to corrode without affecting the iron scale layer.
C OAT I N G S Mechanical/chemical cleaning of scale is the usual process and in the tests described shot blasting followed by acid pickling has been used for cleaning panels. After pretreatment with the three conversion coatings, a white TGIC-free polyester powder coating was applied and the test panels were cured at 200°C for 20 minutes. Film coating thicknesses were in the range 60 to 70 µm and the rub test was used to check cure. Panels were also applied with the same powder at 40 µm for electrochemical impedance testing. Adhesion and salt spray tests were performed to ASTM methods. The results of the cleaning process of oxide scale and conversion coatings were observed by using scanning electron microscopy and it was found that shot blasting alone left some 20 to 25% of oxide scale on the surface. This residue can prevent zinc phosphate crystallization, causing cracking during the dry-off after the pretreatment process resulting in pores and voids on the surface of the zinc phosphated panels. In contrast, the iron phosphated panels showed good surface coverage. It was not possible to examine the nano-treated surface but the salt spray tests were very good, with most panels exceeding 500 hours salt spray and some panels achieved 750–1000 hours salt spray. Zirconium based nanoscaled conversion performed better than iron phosphate and some shot blasted and pickled panels achieved 750 hours salt spray. Using electrochemical impedance measurements as a method for assessing corrosion resistance showed that Zinc phosphating exhibited the best corrosion resistance on panels without oxide scale removal and also on HRS acid pickled samples. Iron phosphating had mediocre barrier properties compared to the other conversion
MAY 2008
POWDER SALES BELIE INDUSTRIAL DECLINE
MAY 2008 In this issue
TECHNICAL
2-3
Pretreatment processes for powder coated HRS
INDUSTRY NEWS
3-6
Architectural applications for liquid and powder fluoropolymer coatings ChinaCoat is the premier coatings event in Asia Cytec offers Crylcoat new generation resins Swan first at coatings show Akzo Nobel: economy has limited impact on Industrial Coatings in US
MARKETS
AN INTERNATIONAL NEWSLETTER MONITORING TECHNICAL AND COMMERCIAL DEVELOPMENTS IN POWDER COATINGS ISSN 1364–5439
6-8
Vietnam becoming boom zone for Southeast Asia paint Jotun with production plant in India Nanotech’s pulse quickens DSM announces investment
Popular media outlets seem to be convinced that the global markets are in free-fall and prophesy a “doom and gloom” scenario for 2008 and beyond. Their indicators are the current dismal reports of the international banking system representing a conglomeration of misguided and, in some notable cases avaricious, lending institutions. They are now realizing their past mistakes and the initial reaction is to drastically curb high risk loans, at least in the foreseeable future. I do not predict any major effect on the global economies if the banks do restrict their unbridled lending spree, and it may prove to be beneficial in the long term if the general public finally appreciate the necessity to live within their means. Escalating prices for energy and food will help to restore fiscal sanity. Industry should not be greatly affected by these adverse market conditions, and the 2007 results from a number of major powder producers tends to substantiate my belief that the coatings industry is gradually moving back into the level of profitability enjoyed in the years prior to 2005. In this issue, the results of 2007 sales of powder coating are reviewed in the annual statements of the larger global producers and these are growing at rates in excess of GNP, a sure sign that
manufacturing industries are experiencing healthy growth. Even in the US, where the economy is claimed to be declining, I have received reports that many powder producers are working twenty four hours a day to meet the current demand from US industry. Abstracted market reports from a number of European countries confirm powder growth rates are well above the average growth rates for liquid coatings. Additionally, the Green Movement grows in strength and adds impetus to powder preference! While powder coatings are almost the mandatory choice for protection of hot rolled steel used in many automotive, appliance and agricultural applications, it is understood that there is a need to clean and pre-treat the metal surface prior to coating in order to maximize the performance of the powder in terms of mechanical and chemical properties. In common with many established pretreatment processes, the conventional techniques of iron or zinc phosphate conversion coatings are arousing concerns related to toxicity and high running costs. An alternative system using a zirconium based nano-structured conversion coatings has the advantages of lower cost and environmental compliance. A paper by
POWDER COATINGS POWDER COATINGS POWDER COATINGS POWDER COATINGS
F O C U S researchers at the University of Ulster has compared these three options and their effect on corrosion protection, and the conclusions are abstracted in the technical section. At a recent meeting of the Powder Coatings Institute, the main topic reviewed was the potential for powder coating wooden surfaces. There has been considerable progress in adapting powder coatings for coating MDF board with both thermal and UV curable powder systems. The big challenge is the powder coating of natural wood surfaces for domestic furniture and this is an opportunity that I believe will be resolved by UV curable powder systems. A high volume, potential market! Sid Harris
TECHNICAL Pretreatment processes for powder coated HRS Powder coatings are well established for the protection of hot rolled steel components used in the automotive, agricultural and appliance industries where they offer good aesthetic, chemical and corrosion resistance qualities. The performance of any coating is influenced by the pretreatment given to the metal substrate prior to the application of the coating. An article by Tepe and Gunay of the University of Ulster examines the corrosive response of HRS after it had been exposed to various surface treatments, before powder coating. The behaviour of three conversion coatings: zinc phosphate; iron phosphate and zirconium based nano-structured conversion was studied. HRS is naturally covered with iron oxide scale and this was removed from the surface by mechanical and chemical processes prior to the application of the surface treatment and powder coating.
2
O N
POWDER
The various treated panels were subjected to the following tests to evaluate corrosion performance: adhesion tests, including crosshatch, pull-off and conical bending, SEM, XPS, salt spray and electro-chemical impedance studies were also performed. Surface preparation of metal surfaces involving cleaning and treatment with conversion coatings ensures good adhesion between the substrate and the coating and increases corrosion and blister resistance. The main pretreatments for steel are iron and zinc phosphate, and both types are widely used in industry. Their economy of phosphating, speed of operation and ability to provide excellent corrosion resistance, adhesion and lubricant properties has established their wide use, but high running costs and concerns about the toxicity and eutrophication effect of phosphating waste, has made it necessary for manufacturers to seek alternative cost-effective and environmentally friendly conversion coatings. The new pre-treatment methods are claimed to provide equivalent or superior performance to the conventional conversion phosphating methods. These nano-structured conversion coatings can be applied at a number of points in the pretreatment process. Many of these new products are based on zirconium and coating thicknesses are in the nano range compared to the micron levels of conventional conversion coatings. Typical coating thickness ranges from 10 to 25 nm. The iron scales formed on HRS are a mixture of iron oxides, lacking in uniformity and therefore offer no barrier protection. This loosely adherent layer is prone to chip and crack under impact and environmental conditions such as heat or humidity, and breaks in the film can promote electrochemical action causing the steel substrate to corrode without affecting the iron scale layer.
C OAT I N G S Mechanical/chemical cleaning of scale is the usual process and in the tests described shot blasting followed by acid pickling has been used for cleaning panels. After pretreatment with the three conversion coatings, a white TGIC-free polyester powder coating was applied and the test panels were cured at 200°C for 20 minutes. Film coating thicknesses were in the range 60 to 70 µm and the rub test was used to check cure. Panels were also applied with the same powder at 40 µm for electrochemical impedance testing. Adhesion and salt spray tests were performed to ASTM methods. The results of the cleaning process of oxide scale and conversion coatings were observed by using scanning electron microscopy and it was found that shot blasting alone left some 20 to 25% of oxide scale on the surface. This residue can prevent zinc phosphate crystallization, causing cracking during the dry-off after the pretreatment process resulting in pores and voids on the surface of the zinc phosphated panels. In contrast, the iron phosphated panels showed good surface coverage. It was not possible to examine the nano-treated surface but the salt spray tests were very good, with most panels exceeding 500 hours salt spray and some panels achieved 750–1000 hours salt spray. Zirconium based nanoscaled conversion performed better than iron phosphate and some shot blasted and pickled panels achieved 750 hours salt spray. Using electrochemical impedance measurements as a method for assessing corrosion resistance showed that Zinc phosphating exhibited the best corrosion resistance on panels without oxide scale removal and also on HRS acid pickled samples. Iron phosphating had mediocre barrier properties compared to the other conversion
MAY 2008