Off-line stencil cleaning with ultrasonic systems is one of the preferred methods for removing trace levels of solder paste from stencil openings. Ultrasonic stencil cleaning equipment manufacturers offer numerous feature options that cater to your cleaning needs, ranging from manual insertion all the way to total automation.
Tips for Selecting a Chemistry with An Off-Line Stencil Cleaning Ultrasonic System
The selection of the cleaning agent is a critical factor. Desirable properties of a reliable stencil cleaning agent include:
- The ability to rapidly dissolve the solder paste flux vehicle
- Material compatibility with the nano-coating and equipment
- Effective at ambient temperature
- Non-flammable
- Low odor
- Completely free rinsing
- Favorable HMIS rating
KYZEN E5631 is a chemistry that fits all the characteristics listed above and has proven to be a high-quality aqueous solution for stencil cleaning.
Steps When Cleaning with an Ultrasonic Immersion System with Water Rinse Cleaning Process
Step 1: KYZEN E5631 cleans solder paste from stencil apertures in ultrasonic cleaning tanks using an operating concentration range for water-soluble soils at 5-10%, and 10-25% for rosin-based and No-Clean soils. The product does not phase separately and requires no mixing before or during use.
Step 2: KYZEN E5631 rapidly dissolves the flux composition for all solder paste types including water-soluble, rosin and no-clean.
Step 3: The maximum wash cycle time is typically less than 4 minutes.
Step 4: KYZEN E5631 easily rinses with water, leaving no residue on stencil surfaces.
Process Note: The active ingredients in KYZEN E5631 are not consumed during the solder paste cleaning process and very little chemistry is lost when running at ambient process temperatures. After the initial charge, no additional make-up chemistry is required until the wash bath is changed. For preventative maintenance purposes, a wash bath changing schedule of 1-2 months is recommended or in the case of heavy use, a one-month change out is suggested.