FOCUS the board. The MDF board manufacturer can influence these properties, and some have now started to market MDF boards specifically for powder coating. Although it may seem that the type of powder coating used is the most important factor, there are other essential aspects that need to be considered. There are two different ways to cure powder coatings for MDF. Thermally cured powder coatings melt and cure by the effect of heat applied for a time that depends upon the reactivity of the powder coating. Alternatively, UV curable powder coating films need to be melted within a precise temperature range prior to UV curing. The first stage of melting is the same for both types and this must be carefully controlled to achieve the desired surface properties of texture, gloss range, scratch and chemical resistance. The most important aspect of both melting and curing temperature control is the need to ensure that all parts of the MDF are subjected to exactly the same temperatures. Lack of uniform temperature control during both melting and curing is often the root cause of failure in the powder coating of MDF board. Coating line technology is of the utmost importance in achieving good quality powder coated MDF board, and old metal coating lines are generally unsuitable for use with MDF. Since MDF has poor thermal conductivity the oven needs to be designed to give a very homogeneous temperature distribution. When the coated MDF is heated with infrared irradiation the applied powder film and the MDF board surface rapidly reach the required temperatures to melt and cure the powder. This is achieved with minimal internal heat stress in the core of the board due to its slow heat conductivity. The other essential is to ensure that the IR irradiation is uniform in all areas including the edges, and modern
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IR ovens for MDF give very narrow temperature distributions of less than 15°F. Use of carefully sited sensors will enable the coater to set the desired temperature profile and regular monitoring throughout the product run will ensure consistency of both melt and cure cycles. In UV curing of powder it is also necessary to carefully control the UV intensity and dosage. This requirement has been difficult to achieve in practice and may be the reason why it has been a problem to reach the desired quality standard with UV cure. Product specifications are the final piece of the performance jigsaw and these will vary considerably with the end use application of the coated MDF board. Success or failure may depend upon this capability and needs to be assessed in conjunction with the customer before making the decision to powder coat MDF board. Article entitled “Powder Coating Medium Density Fiberboard: A New Approach to Success” by Thomas Schmidt of Tiger Coatings, Powder Coating, Jun 2004, 16-24. Powder Coating is published 10 times a year by CSC Publishing Inc, 1155 Northland Drive, St. Paul, MN 55120, USA
C OAT I N G S announced in May 2002. For the first six months of the year, PPG reported net income of $298 million, a 30% increase from the same period a year earlier. Sales for the six-month period rose 7%, to $4.69 billion. The company said secondquarter sales for its coatings segment rose 8%, to $1.35 billion, to set a record high for any quarter, with the sales gain resulting from stronger volumes in the architectural, industrial, automotive OEM, aerospace and automotive-refinish businesses and the strengthening of foreign currencies. Coatings- segment operating earnings were $223 million, also a record for any quarter and up 8.8% from the prior-year period. The company said increased volumes and improved manufacturing efficiencies “more than offset additional selling expenses in the architectural business, the impact of cost inflation and lower selling prices.” For the six-month period, coatings operating income was $408 million, a 17.6% increase from the previous year. Coatings sales for the six-month period rose 10.7%, to $2.628 billion. Coatings Flash, 26 Jul 2004, Website: http://www.coatings.de
INDUSTRY NEWS Sales record for PPG Industries PPG Industries Inc. reported second-quarter net income of $183 million, a 20% increase from the second quarter of 2003. Sales for the quarter rose 5.7%, to $2.43 billion, a record-high total for any quarter in the company’s history. Net-income results include after-tax charges of $3 million related to a previously announced decision to begin expensing stock options in 2004, and $6 million to reflect the net increase in the current value of the company’s obligation under an asbestos-settlement agreement
Akzo Nobel’s operational performance up in 2Q 2004 Akzo Nobel reports second quarter net income of €216 million, up 7% compared with the second quarter of 2003. Net income including nonrecurring charges was down to €112 million. Coatings are clearly up due to strong growth and cost savings. Autonomous growth mainly took place in Asia Pacific and the United States. “The combination of sales growth and restructurings resulted in a 7% increased operating income,” said Akzo Nobel’s new CFO Rob Frohn. “Decorative Coatings is under pressure from a hesitant business climate in Western
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FOCUS Europe and Turkey. Marine & Protective Coatings, Industrial Finishes, and Powder Coatings improved further. The performance of Car Refinishes is suffering from pressure on margins and announced a worldwide restructuring program.” Coatings Flash, 26 Jul 2004, Website: http://www.coatings.de
Russkie Kraski launched in Mar 2004 a $2.5 M plant for powder coatings production Russkie Kraski (Russia) in Mar 2004 put into operation a new $2 M plant, Yaroslavskii zavod poroshkovykh krasok (YaZPK) for powder coatings production. YaZPK will produce powder coatings from imported raw material. Annual domestic demand for powder coatings is 20,000 tonnes/y, and 18,000 were imported. There are currently 12 domestic producers of powder coatings materials. Vestnik khimicheskoi promyshlennosty, 27 May 2004, 30 (2), 40-41(in Russian)
Low curing polyester powder coating NATOCO, a paint maker in Japan, has formulated a polyester powder coating technology with a 30deg C reduction in cure temperature. The coating features high flexibility and high weatherendurance. Carboxylic acidterminated polyesters cross-linked with Primid were employed to achieve the said properties. APCJ, Asia Pacific Coatings Journal, Jun 2004, 17 (3), 6
MARKETS North American coatings market faces slow growth The market for coatings in North America is mature with growth only matching GDP. North American producers are under
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pressure from high energy costs and they are responding by introducing technology advancements and value added products. The North American coatings market is pegged at $21.2 bn with estimated growth at 2.2% to 2/9% /y. Market growth is anticipated to increase to 3% to 3.6% if the American economy continues to recover. In general the North American coatings market is oversupplied especially for powder coatings. High energy prices are forcing producers to research and develop coatings, which can be cured at lower temperatures. BASF’s efforts in the automotive coatings sector are described. Chemical Market Reporter, 21 Jun 2004 (Website: http://www.chemicalmarketreporter.com)
Overview of European powder coated aluminium market Otefal Engineering, Italy has been the pioneering European company in developing flexible systems for powder coating aluminium extruded sections and this market continues to expand as polyester powder coating has practically become the only alternative to anodising in the large outlets for high-performance architectural aluminium products, such as door, windows, curtain walling, and cladding. A paper presented by Dr Irene Marcolungo of Otefal describes the need for flexible plant to cater for the market demands for powder coated extruded sections and sheet, distributed in small lots, in dozens of different colours, through a network of many hundreds of distributors and dealers, supplying tens of thousands of construction designers, or “aluminium Smiths”. The task of meeting this demand is justified by the high added value, which can be more than twice the price of the original extruded sections. Demand for powder-coated aluminium is fuelled by the increasing use of
C OAT I N G S window and door systems for residential housing, in Germany, Italy, Spain, Portugal and Greece, which amounts to 1,200,000 tonnes/year. This added value in a highly fragmented market explains the ever increasing demand for flexible finishing plants meeting the need for production of many different finishes each day, that achieve just-in-time deliveries to stockists and dealers who are hard pressed by their customers. In this market, extruded sections account for the major tonnage, with sheet and coil covering about 10% of the total requirement. While this 10% outlet may seem relatively unimportant, it is a key component of the overall demand as a complement to the extruded systems in aspects that necessitate specialized craftwork. There are many kinds of flexible powder coating lines. The vertical coating line is the least flexible option although it gives maximum productivity. An ideal option for maximum flexibility is the manual coating line where a range of different colours can be applied to sheet or bars. It is estimated that some 600 toll coaters operate these types of plant, coating some 58,000 tonnes of sheet compared to the 32,000 tonnes of sheet coated by coil or continuous coating. A compromise between flexibility and productivity is found in the coil coating of rolled metal, where a careful production planning of metal thicknesses and widths will permit easy adjustment of the stoving conditions. The essential requirement is a twinbooth arrangement having a one hour cleaning time which in theory could cater for 24 different colours in a 3 shift working day. The best combination for the system market is to have two or more painting lines with different characteristics. A medium speed line for major runs of most requested colours such as white,
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