Solder Paste

Solder Paste Formulas for Surface Mount and General Electronic Assemblies

All Kester solder paste formulas are manufactured using the highest quality raw materials available. Kester's worldwide research facilities work together to design solder paste formulas which bring the latest technological deve1opment to electronic manufacturers around the globe. Standard operating procedures are used throughout Kester's worldwide manufacturing Facilities in the production of oxide free solder powders and paste fluxes. A high level of quality and consistency is assured through process control techniques. All product reliability and chemical property testing is conducted by Kester's own certified Chemical Analytical Laboratories.

The solder paste formu1as listed represent the current product recommendations at the time of printing. Please contact Kester's Technical Service Department for a specific product recommendation for your application.

Water Soluble Solder Paste Formulas
Characteristics Product Characteristics Residue removal Method Expected Tack Life Atmosphere Required for Reflow Compliant Specifications
R596 Standard water soluble formula for all reflow applications. It is resistant to high temperature and humidity Use de-ionized or soft tap water at 130-150°F 8+ hours Air or Nitrogen ANSI/J-STD-004
R596-3 High activity formula for advanced microelectrons applications. Use de-ionized or soft tap water at 130-150°F 6+ hours Air or Nitrogen ANSI/J-STD-004

No-Clean Solder Paste Formulas
Characteristics Product Characteristics Expected Tack Life Atmosphere Required for Reflow Compliant Specifications
R244 Full residue, standard no-clean paste for all reflow applications.
R244 is an industry standard formula that combines many good properties into a user friendly product
8+ hours Air or Nitrogen Bellcore Issue 3
TR-NWT-000078
ANSI/J-STD-005
R244C Full residue, more active and tackier version of R244. Designed for fast speed printing applications. 8+ hours Air or Nitrogen Bellcore Issue 3
TR-NWT-000078
ANSI/J-STD-005
R253 Full residue, fast wetting paste for applications where post soldering residues need to be compatible with In Circuit Testing. 8+ hours Air or Nitrogen Bellcore Issue 3
TR-NWT-000078
ANSI/J-STD-005
R253-5 Full residue, more active version of R253. Designed for fast wetting applications and better compatibility with In Circuit Testing. 8+ hours Air or Nitrogen Bellcore Issue 3
TR-NWT-000078
ANSI/J-STD-005
R289TM Full residue, fast wetting paste designed to meet the needs of high reliability 8+ hours Air or Nitrogen Bellcore Issue 3
TR-NWT-000078
ANSI/J-STD-005

Rosin Mildly Activated Solder Paste Formulas
Characteristics Product Characteristics Expected Tack Life Compliant Specifications
R229-25 Good activity formula for good solderability. Designed to have thixotopic property that would suit fine pitch type of mounting. 8+ hours IPC-SP-818
R229 Design with thixotopic characteristic suitable for syringe dispensing, wash screen printing and actual stenciling. High solubility of residue in solvent. 6+ hours IPC-SP-818