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Approved Solven ts 25 Understanding the Cleani ng Process fo r Autom atic S tencil P rinte rs

Solvent Checklist

• Chemical compatibility with the solder paste

• Dissolve the flux & free up the powder spheres

• No bad reaction with paste that affects paste viscosity

• Process compatibility

• Dry evenly and at a controlled rate

• No adverse paste reactions

• Leave no residue

• Equipment compatibility

• Does not attack valves, seals, pumps, reservoirs

• Safety & health

• Non-toxic, non-flammable, low- (or no-) odor

Understanding the Cleaning Process for Automatic Stencil Printers

Approved Solvents

Understanding the Cleaning Process for Automatic Stencil Printers

Solvent conclusions

• Evaporation rate of chemistry critical to printer application

• Good indicator is the flash point of the material – the lower the

flashpoint – the better the evaporation rate

• Test for residues – mirror test

• Avoid water-based solvents for the printer

• Petroleum based solvents should be also be avoided

• Check with your paste manufacturer for compatibility of solvents

• Work with chemistry vendors for best application

• Always start wipe cycle with the solvent wipe

• Match the solvent to the material and application – one size does

not fit all

Understanding the Cleaning Process for Automatic Stencil Printers