PRODUCT :- PHOTO-IMAGEABLE SOLDERMASK. COMPRISES OF A LIGHT SENSITIVE LIQUID PREPARATION USED IN PHOTO LITHOGRAPHIC APPLICATIONS, IN THE MANUFACTURE OF SEMICONDUCTOR MATERIALS 2 PACK COATING SYSTEM. PART 1 IS THE HARDENER AND THE 2ND CALLED THE RESIST. ONE OF THE 2 PARTS WILL CONTAIN A PIGMENT, OFTEN GREEN BUT OCCASIONALLY OTHER COLOURS. EACH PART HAS IT OWN UNIQUE REFERANCE NUMBER BUT THEY ARE SOLD AND PRESENTED WITHIN THE SAME CONSIGNMENT IN THE APPROPRIATE RATIOS, EG: 20 X 1KG TINS OF HARDENER WITH 20 X 3KG TINS OF RESIST. WHEN MIXED THE 2 PARTS CONTAIN THE FOLLOWING COMPONENTS: EPOXY/ PHOTOSENSITIVE RESINS, ORGANIC SOLVENTS, PHOTO INITIATORS, SILICATES SILANES. ADDITIVES VARY DEPENDING ON CUSTOMER SPECIFICATIONS. THEY ARE USED TO COAT CIRCUIT BOARDS. IT OFFERS A PROTECTIVE NON-CONDUCTIVE DIELECTRIC LAYER THAT WHEN APPLIED ONTO THE PRINTED CIRCUIT BOARD ASSEMBLY WILL PROTECT THE ELECTRONIC ASSEMBLY FROM DAMAGE DUE TO CONTAMINATION, SALT SPRAY MOISTURE, FUNGUS, DUST AND CORROSION. HARDENER AND RESIST SOLD/PRESENTED TOGETHER AND IN THE APPROPRIATE RATIOS FOR MIXING AT THE END USER PREMISES. WHEN MIXED/THINNED THE COATING IS APPLIED TO THE WHOLE CIRCUIT BOARD AND 'PRE BAKED' TO REMOVE THE SOLVENTS. CIRCUIT BOARD CAN BE COATED IN VARIOUS WAYS INCUDING 'CURTAIN COATING' & 'SPRAY COATING'. CIRCUIT BOARD HAS A TEMPLATE/ IMAGE APPLIED AND THEN UNDERGOES A UV CURING STEP. ALL COVERED AREAS REMAIN UNCURED AND THEN THE BOARD IS SENT THROUGH A 'DEVELOPER' SOLUTION TO REMOVE ANY UNCURED COATING BEFORE UNDERGOING THE DRYING PROCESS

CLASSIFICATION HAS BEEN DETERMINED IN ACCORDANCE WITH THE FOLLOWING:- GENERAL INTERPRETATIVE RULES (GIR)S GIR 1 HAS BEEN USED TO CLASSIFY THIS PRODUCT BY THE TERMS OF HEADING:- 3707 - CHEMICAL PREPARATIONS FOR PHOTOGRAPHIC USES (OTHER THAN VARNISHES, GLUES, ADHESIVES AND SIMILAR PREPARATIONS); UNMIXED PRODUCTS FOR PHOTOGRAPHIC USES, PUT UP IN MEASURED PORTIONS OR PUT UP FOR RETAIL SALE IN A FORM READY FOR USE. GIR 5B HAS BEEN USED TO IDENTIFY THE TYPE OF PACKAGING (PACKAGED IN TINS) GIR 6 HAS BEEN USED TO CLASSIFY THE GOODS TO SUBHEADING LEVEL:- 370790 - OTHER THAN SPECIFIED ELSEWHERE IN THIS HEADING CN CODE:- 37079090 - OTHER THAN DEVELOPERS AND FIXERS ALSO CLASSIFIED IN ACCORDANCE WITH SECTION NOTES 2 & 3 TO CHAPTER 37 HSEN TO CHAPTER HEADING 3707