Electrical and Electronic Resins - Tetrachim

1 3 Scotchcast Electrical and Electronic ResinsIntroduction 3M Scotchcast powder Resins are a series of one-part, 100 percentsolids systems offering: Fast curing Excellent Electrical properties Excellent thermal and mechanical shock resistance Superior cut-through resistance High adhesionPowder ResinsSelection and Application Excellent chemical andmoisture resistance High to low flow characteristics Superior electrostatic coatingcapabilityThe Resins are manufactured by a fusion-blend process whichensures that each particle of powdercontains all the componentsnecessary to effect a complete cureand attain the stated performanceproperties.

2 Powder resin selectiondepends primarily on the method ofapplication five most commonly usedmethods of applying powderresins are: Fluid bed dip Manual spray Automated integral insulationspray system Electrostatic spray Electrostatic fluid bed23 Selection processThe best way to select the properScotchcast powder resin is to considerthe needs of the application and theproposed application method. Besidesevaluating the property values andproduct descriptions in the chart onpages 4 and 5, consider the following: Does the resin selected meet therequirements of the application?

3 Is ULrecognition required? What problems have existed withother methods or products whichhave been used or evaluated? Willthe selected resin overcome theseproblems? Which application process is bestsuited for the product selected? Can the part, by virtue of its sizeand configuration, be coated usingthis process? What masking and coatingthickness is needed? Is application equipment available?Can it be used to apply the productselected? Is sufficient floor space availablefor automation, including an areafor part-surface preparation, aconveying system, dust collectionand powder storage (coolers)?

4 Canair requirements, , use ofcompressors, blowers, dryers, bemet? Are ovens available?ApplicationSuccessful coating with powder resinsis accomplished in four basic steps:1. Clean the partOne or both of the followingprocesses may be necessary tocomplete this step. Removal ofrust, dirt, oxide and othercontaminants can be accomplishedby sandblasting, vapor de-greasing,or steam Preheat the partPreheating may be omitted if partsare to be coated electrostatically atroom temperature, in which casethey must be thoroughly driedbefore coating to preventoutgassing. Forced air ovens,induction heating, radiant heatingand resistance heating are fourcommon methods used to preheatparts, cure the resin or Coat the part Preheated partsWhen applied to preheated parts,powder particles melt, flowtogether, fuse and then are dipping or spraying, thecoating thickness depends on thetemperature of the part, theduration of the dip/spray, and themelt rate and melt viscosity of thepowder.

5 If the powder is appliedelectrostatically to a preheatedpart, coating thickness depends onthe temperature of the part, theduration of the powder application,the voltage applied to the powder,the chargeability of the powder andits melt rate and melt partsWhen unheated parts are coatedelectrostatically, the chargedpowder resin particles cling to thegrounded part. The coatingthickness depends on the durationof the powder application, thevoltage applied to the powder andthe powder s Cure the resin(See #2, Preheat the Part sectionfor methods of supplying therequired heat.)

6 When large, preheated parts arecoated, the mass of the part mayhold the heat necessary to cure theresin fully without , smaller parts may lose somuch heat during coating that theyrequire a postcure to obtain fullcure. The time/temperaturerelationships necessary to obtainfull cure are given in the chart andon individual product informationsheets. These time/temperaturerelationships do not include thetime necessary to heat or reheat thepart to the curing temperature. Theuser must make this determinationand start the time cycle when thetemperature is Insulation SystemsInsulation systems established per UL1446 and IEC 85 requirements are available for various Scotchcastresins up to class H (180 C).

7 Themajor system components includeScotchcast resin as integral groundinsulation, magnet wire, interlayerinsulation, and molding material. Minor components such as 3 MElectrical Tapes, sheet insulation, tiecords, lead wires, varnish, etc. havebeen added, making the 3M ElectricalInsulation Systems ideal for mostapplications. The Systems arerecognized in ULfile E163090(OBJS2). Please refer to the separateScotchcast Electrical InsulationSystems brochure for Scotchcast powder Resins arealso recognized by ULas componentinsulation of class B per are listed in ULfile E35075(QMFZ2).

8 Powder Resins TypicalProperty DataUL System1446 ApprovalFile NumberE163090 Temp ClassProduct NumberCure Schedules (Temp/Time)DescriptionRRRRB260 This widely used, well known product is used primarily in 149 C (300 F) 30 minFspray and fluid bed dip applications. 177 C (350 F) 10 minH260 CGCoarse ground version of 260 for improved fluidized bed204 C (400 F) 30 secperformance. C (450 F) 20 secB262 This resin has excellent flow characteristics which produce a149 C (300 F) 40 minuniform coating in applications such as resistance heated177 C (350 F) 20 minbobbin wound coils.

9 It is used primarily in spray and fluid204 C (400 F) 60 secbed dip C (450 F) 30 secB263263 is used primarily in spray and fluid bed dip applications149 C (300 F) 30 minFand has been designed for use where high temperature177 C (350 F) 10 minHcut-through resistance is required. C (400 F) 30 sec232 C (450 F) 20 secB265 Low melt viscosity and minimum build make this unfilled149 C (300 F) 60 minpowder ideal for a variety of coating, bonding and177 C (350 F) 20 minimpregnating applications, notably coating from a C (400 F) 5 minULcomponent recognition ULFile E35075232 C (450 F) 2 minB270 This ULRecognized resin is used primarily in 149 C (300 F) 30 minspray and fluid bed dip applications and has been 177 C (350 F) 10 mindesigned for higher temperature cut through and204 C (400 F)

10 30 secbridging gaps around shading bands on C (450 F) 20 secLiquid Patching CompoundB5096 Used for patching Scotchcast powdered Resins , this two-part 25 C (77 F) 24-48 hrsresin is a liquid, room temperature-curing, thixotropic C (140 F) 2 hrsULrecognized. Hardness of 85 Shore D. Mix ratio by weight95 C (203 F) 1 hris 10:0 (A:B). ULcomponent recognition ULFile E35075B5133 This product accepts a charge very easily, which makes149 C (300 F) 30 minit ideal for electrostatic coating techniques. This product177 C (350 F) 10 minis designed to permit the thin coating of cold as well as heated204 C (400 F) 30 secparts such as capacitor cans, transformer covers, and C (450 F) 20 secF5230N5230N is an updated version of the 5230 resin C (350 F) 15 has superior charging capabilities and is designed to204 C (400 F) 6 smooth uniform coatings using the electrostatic fluid bed232 C (450 F) 3 method.