to dominate this market, whichthey all agree offers a greaterpotential for growth than mostother areas of industrial coatings.

In the last two weeks, Oxyplastof Belgium have completed thetenth annual meeting of their 23licensees worldwide and many oftheir clients stayed on for arefresher course to update thepowder coatings technology. It wasinteresting to note that all of theirlicensees are situated outsidemainland Europe and NorthAmerica – the very regions that Iwould expect to benefit most fromtheir modern expertise in thisfield. I am somewhat disappointedthat companies that have themost to lose in the immediatefuture are overlooking assistancethat is much closer to home.

Sid Harris

TECHNICALNew advances in high speed curingfor powder coatings

A paper presented by MartinHolliday, the Technical Director atDuPont Powder Coatings UKdescribes the progress made atDuPont in the development ofhigh speed curing systems forpowder coatings.

The main advantages ofpowder coatings are: the VOCfree technology; ease ofapplication with very highdeposition efficiency; reducedhealth hazards; a wide range offinishes and very goodeconomics. Another major benefitis the capability to apply powdercoatings at high speeds and tocure them rapidly.

The first option discussed isthe UV curing of powder coatings.These products were developedto offer lower curingtemperatures, shorter curing timesand improved coating properties.They also represent a powdercoatings solution to new marketopportunities that are currently

dominated by solvent basedpaint, particularly in applicationsto wooden substrates andplastics. A comparison is givenbetween UV powder coatings andconventional thermosettingpowder coatings. Whileconventional powder coatingsrequire high curing temperaturesin the range 150-200°C, longcuring times of 10 minutes ormore, and simultaneous meltingand curing processes, the UVcuring alternative systems willcure by irradiation with UV lightat temperatures as low as 100°C,giving short curing times ofseconds rather than minutes, anda separation of the melting andcuring phases. These coatingswere developed for application toheat sensitive substrates such asMDF board and wood, pre-assembled parts, and heavymetal substrates containing partswith high heat capacities.Customers are now able tobenefit from short processingtimes (melting in 2 minutes andcuring within seconds), minimalthermal stress to the substrate, asuperior surface finish resultingfrom the separation of meltingand curing stages, and a reducedspace requirement for the curingprocess. Commercial installationshave been started successfully inEurope and the US.

Many potential customers,however, need to utilize existingequipment and require powdercoating options that are normallycarried out at high temperatures,with the added attraction of muchshorter curing times. Infraredheating offers advantages overconventional convection ovencuring by utilizing the rapid heattransfer of short and mediumwave infrared irradiation. Tests onthe efficiency of different short tomedium wave bands have shownthat emissions in the nearinfrared zone (termed NIRheating) have the capability toefficiently cure powder coatingfilms by speeding the curing rateby a factor of 100 to 200. ThisNIR emission lies in the range of

800 to 1,200 nm. This newheating method enablesconventional powder coatings tomelt and cure within 3 seconds.In comparison with conventionalheat and conventional IR, the NIRheaters give a heating intensity inthe MW/m2 range whileconventional heating lies in theKW/m2 range. NIR heats with partof the radiation absorbed at thecoating surface, while theremainder penetrates the coatingand is absorbed throughout thecoating thickness, with someabsorption of NIR by thesubstrate. NIR radiation can alsobe reflected back into the coatinglayer by metallic surfaces tointensify the heating effect. Theconventional heating processeshave the energy fully absorbed atthe coating surface, and thecoating and substrate are heatedby the conduction mechanismonly. This process offers theapplicator: extremely shortprocessing times; low heat up ofthe substrate for massive partsresulting in a considerablereduction of energy consumption;compact oven design; and thepossibility to clean and cure withone equipment.

DuPont had developed powdercoatings for low and normalspeed coil coating applicationsthat were successfully introducedsome years ago. They have nowdeveloped coil coatings powdertechnology for high speed coillines with the objective of meetingline speeds of up to 100 m/min.Line speeds in excess of 100m/min, have been achieved bythe use of cloud chamberapplication technology. Othernovel application technologiesdesigned to facilitate speedcoating are: electromagneticbrush; and powder bladeapplicators.

A comparison of curingtechniques lists IR at 60-90seconds; induction heating at 15-20 seconds; IR + UV 2-3minutes; and NIR at 2-10seconds. Product performance ofthe rapid curing materials

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includes mechanical propertiesshowing impact resistance of 160in/lb; OT bend; extreme flexibilityshown by deep draw testing;Erichsen cupping 8mm; andadhesion GT0.

The future for powder in thecoil coating industry is excellentwith ultra rapid cure powdercoatings based on TGIC freepolyesters and acrylics.

The work at DuPont has notbeen confined to radiation curablepowder but includes new curingchemistries that offer lower curetemperatures or faster cure usingconventional stoving systems. Theultra low bake systems arealready well established as agrowth market for powder coatingof MDF board. In the plant designthe MDF board is preheated byIR to around 120°C, and left for90 seconds prior to application ofthe powder coating at filmthickness around 300 mm. Thecoated board is then subjected toIR heat for 30 to 90 seconds,dependent upon the thickness ofthe MDF board, and finally curedat 140°C for 10 minutes or byadditional IR.

Paper entitled “New Advances in High SpeedCuring for Powder Coatings” by MartinHolliday, Technical Director of DuPontPowder Coatings UK, presented at one daysymposium organized by the Yorkshirebranch of the Institute of Corrosion inSheffield, 4 Jun 2003

INDUSTRYNEWS

BASF’s industrial coatings businessfocuses on profitable growth

The Industrial Coatings businessunit of BASF Coatings willstrengthen its focus on thedemands on major individualmarkets. To accomplish thisobjective, the business unit willcapitalize on the company’sstrong position in the automotivesector, restructure businessoperations and consolidate itsproduction basis. The action plan,

which is scheduled to beimplemented by 1 Jan 2004,focuses the Industrial Coatingsbusiness on profitable growthmarkets. In 2002, sales inIndustrial Coatings accounted forabout 20% of BASF’s globalCoatings division. The productsare used in a broad range ofapplications and industries, suchas automotive suppliers,commercial vehicles, householdappliances, furniture andconstruction.

The Industrial Coatingsbusiness unit will be reorganizedas follows: In the Precoatingsarea (coil coatings and foil) BASFis a global market leader and wellpositioned to increase its marketshare. Further strengthening itsbusiness in Europe and NAFTAand establishing a strong supplierposition in China are the primaryobjectives of a strategy that isbased on innovation and newproduction applications. To ensurethat the research anddevelopment activities are moreclosely connected to the business,Technology Management willbecome part of the Precoatingsarea. In Metal coatings, BASF willstrengthen its core competenciesin the automotive andtransportation markets. Both theAutomotive OEM Coatingsbusiness unit and the Automotiverefinish business unit will expandactivities in metal coatings withautomotive suppliers andcommercial vehicles. Theemployees of the IndustrialCoatings business unit who havebeen working in automotiverelated product areas will transferto Automotive OEM coatings andAutomotive Refinish Coatings asof 1 Jan 2004. In PowderCoatings BASF will concentrateits activities at the Verbania sitein Italy by 1 Jan 2004 anddiscontinue product developmentand manufacturing of powdercoatings in Munster-Hiltrup. Byconsolidating the powder activitiesat one site, the business willcreate a better platform tocapitalize on the growth market of

powder coatings. Wood Coatingswill be organized in 3 new entitiesas of 31 Dec 2004. GlasuritConstruction operating out ofMunster-Hiltrup encompasseswindow coatings and radcurecoatings (doors). FurnitureCoatings operating out of Romanod’Ezzelino, Italy, will include allwood coatings activities forfurniture. The Speciality/Automotive Dashboard businesswill be integrated in theAutomotive OEM business unit tobetter utilize the synergies withthe automotive sector.Manufacturing productdevelopment and laboratoryactivities for furniture coatings willbe discontinued in Munster-Hiltrupas of 31 Dec 2003. In PowderCoatings and Wood Coatings,about 70 employees at theMunster site will be affected bythe new structure. BASF Coatingsplans to integrate theseemployees in other units thathave a demand for additionalpersonnel. According to Dr GeorgZwissler, Group Vice PresidentIndustrial Coatings, its neworganization enables it to bettertake advantage of marketpotentials. It complements theactions that BASF has taken overthe last 3 years. Even in thedifficult economic marketconditions these measures havecontributed significantly to improvethe company’s results in IndustrialCoatings.

Press release from: BASF Group, Germany.Website: http://www.basf.de (5 Sep 2003)

Tip Top Stahlgruber makes newautomotive balancing pieces

Tip Top Stahlgruber (Germany)has begun making newautomotive wheel balancingpieces. They are produced ofquality zinc alloy. Their surface isfinished with a special powdercoat. The new pieces are thefirm’s response to the new EUdirective that bans the use ofclassical lead balancing pieces forautomotive wheels for

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