Cleaning For Electronics Wash away the worries of contaminants.
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Transcript of Cleaning For Electronics Wash away the worries of contaminants.
Cleaning For ElectronicsWash away the worries of contaminants
Why Clean?Possible Applications and Contaminants
Customer – military – telecoms – safety critical
Coated board
Coating/ Potting
protection
CustomerCustomer
(“no clean” process)
Finished (dirty board)
REFLOW
Surface mount
(IR, Vapour etc)
SOLDER WAVE
Conventional
(through hole) Flux
Bare board (dirty after 16
processes)
PRINTED CIRCUIT BOARD PRODUCTIONCircuit diagram photo
plotted onto bare copper board/etched
CLEANING
CLEANING
of stencils/glue applications
CLEANING OF OVENS OR TRANSPORT CHAINS
Cleaned board
CLEANING
Populated
board
Components
Solder paste/adhesive (Stencilling)
For “failed board” REWORK – cleaning of
flux/adhesive/coatings
WHAT CLEANING MAY BE REQUIRED?
FLUX RESIDUES - Assembled PCB’s - Ceramics - Carrier Frames / Jigs + Reflow or Wave equipment
SOLDER PASTE - Stencils / Dispenser Needles - PCB’S (Misprints / Rework)
UNCURED SMT ADHESIVE - Stencils / Dispenser Needles - PCB’S (Misprints / Rework)
OTHER PROCESS CONTAMINANTS - PCB board Preparation (HASL etc) - Handling / storage
CLEANING OF FLUX RESIDUES
– OBJECTIVE - No visual residues - Ionic contamination <1.5 µg/ cm2 NaCl equivalent - High insulation resistivity ( SIR testing IPC TM 650)
Ideally achieved with minimum cost!
A LITTLE CHEMISTRY!
METAL OXIDE + FLUX = CLEAN METAL + WATER + SALTS
Flux wets the metal surfaces and a simple acid/base reaction cleans the surface
Clean metal surfaces can then bondi.e. soldering can take place
Some residues such as salts, un-reacted fluxes/activators are corrosive and conductive and so must be removed
“NO CLEAN” PROCESSES LOW / ZERO RESIDUE IONIC PASTES / FLUXES
WORK EXTREMELY WELL, INCLUDING WHEN CONFORMALLY COATED, SO LONG AS…
- Process is optimized - No residues from earlier stage of board preparation, often >12 processes +
handling -· Fingerprints etc· Oils / Greases (HASL)· Particulates (Solder balls, fibre glass, metal oxides, other contaminants)
CLEANING IS STILL REQUIRED FOR OTHER ASSEMBLY PROCESSES - Solder Pastes / Adhesives
- Stencils / Dispenser Needles - PCB’S (Misprints / Rework)
“LEAD-FREE” PROCESSESTRADITIONAL LEAD/TIN/SILVER ALLOYS HAVE BEEN REPLACED
WITH “NO LEAD” SYSTEMS - TIN/COPPER/SILVER ALLOYS
• CHANGE WAS REQUIRED DUE TO RoHS WHICH WAS IMPLEMENTED IN JUNE 2006
• CLEANING OF “LEAD FREE” FLUX RESIDUES IS ESSENTIAL BUT DIFFICULT
- Increased temperature means that the residues are “baked on” and are much
harder to remove than traditional leaded flux residues
Aqueous-Based CleaningThe Safewash Product Range
SAFEWASHSWA, SWAJ, SWAS
• Non-flammable• All supplied at ready to use concentration• SWAJ suitable for use on sensitive metals
such as copper and aluminium• SWAS good for no-clean fluxes, is easier to
rinse and has very low odour• All foam – unsuitable for high pressure spray• All will absorb 5-15% of their weight in fluxes
and maintain cleaning power
PRODUCT ACTIVE CONTENT
SWA 23%
SWAJ 23%
SWAS 26%
SAFEWASHSWAF, SWAP, SWAC
• Non flammable• Low foaming• SWAF and SWAC supplied as
concentrate – dilute to 5-25% in deionised water
• SWAP ready to use• SWAP suitable for use on sensitive
metals• Can be used in ultrasonic, dishwasher,
spray in-line cleaning or pressure washing.
PRODUCT ACTIVE CONTENT
SWAF 100%
SWAP 26%
SWAC 100%
• Excellent cleaning performance • Removal of all types of flux residues from
PCBs and general degreasing applications• Supplied as a concentrate: reduced
transportation and packaging.• Very low toxicity • Effective over long periods of time by filtering. • Low foam cleaner, suitable for use in:
dishwasher in-line pressure systems Ultrasonic spray under immersion
SAFEWASH TOTALSWAT
• Non flammable.• Removes pastes and adhesives.• Ready to use (44% active).• Low foam – suitable for use in ultrasonic or spray machines for stencil
cleaning.• Solder paste uptake of up to 50% without affecting cleaning performance.• pH drops from 10.3 to 6 at this loading BUT is no indication of adhesive
content.• Shake before use – clouds at 23-24°C.
SAFEWASH SWAX
SAFEWASH
+ CORROSION INHIBITOR
SUPER + CORROSION INHIBITOR
ULTRASONIC
LOW FOAM
SWAP
SWASSWAJ
SWA SWAF or SWAC
SWAX
SWMN or SWMP
MECHANICAL PARTS
(DEGREASING)
STENCIL ADHESIVES
FLUX RESIDUES AND SOLDER PASTES
SWAT
NEUTRAL PH
SWNS or SWNP
• Water based• Non-flammable• Designed for cleaning reflow ovens and wave
solder machines• Excellent cleaning performance • Removes of all types of flux residues and
general dirt/grease• Supplied ready to use in 500ml spray bottle • Very low toxicity
REFLOW OVEN CLEANERROC
A customer trial of ROC…………
ROC
Before cleaning……….
Applying ROC……….
Cleaning…………
Left: Before cleaning
Right: After cleaning with ROC
Solvent-Based CleaningThe Electrolube Product Range
• Flammable: Not suitable for use on live equipment
• Fast dry-time • Best choice to remove ionic residue; also suitable for removing grease and flux residue• Compatible with most plastics; not suitable on polycarbonate
ULTRASOLVEULS
• Flammable: Cannot be used on live equipment
• Fast-drying• Best for cleaning flux residue, but can be used for ionic residue and heavy grease• Safe on most plastics; not suitable on polycarbonate or polystyrene
Also available – HFFR: Hexane-Free Flux Remover
FLUXCLENEFLU
• Non-flammable• One of the slowest evaporation rates of all the solvent based cleaners• Best for cleaning solder pastes and adhesives• Also suitable for flux residue, ionic residue and heavy grease• Not suitable for use on ABS, polycarbonate or polystyrene• Also available as SSW: 100 wipe tub dispenser• ULC is also suitable for this application
SCREEN AND STENCIL SOLVENTSSW, SSS
Substrate
PCB Cleaning
GlassMagnetic Tape
HeadsPrinters
General
Residue Type
Electronic Contacts
Flammable
PRSPrintasolve
GLCGlass cleaner
VIDMagnetic Head
Cleaner
Non-flammable
ULCUltraclens
ECSPElectronic cleaning
solvent Plus
IPAIsopropyl alcohol
Ionic Residue
Flux Residue
Solder Paste
LFFRLead Free
FluxRemover
FLUFluxclene
FRCFlux
Remover
Non-flammable
Flammable
CCCContact Cleaner
ULSUltrasolve
SSS & SSWScreen and
Stencil Solvent
MDSMetal Degreasing
Solvent
DGCDegreaser
Heavy Grease
START
Thank you for listeningPlease visit www.electrolube.com for more information