Understanding_ the_Cleaning_Process_for_Automatic_Stencil_Printers - 第21页

Paper Compare d (Dr y Wipe Data Onl y) High End Paper T y pical Paper Paper Using Glue Base Weight (oz/per y d²) 1. 87 1.5 6 1 . 11 T ensile Strength (LB’s) 29 31 16 Thickness (Mils) 15 12 11 Absor ption (ML H²O/M²) 3 91…

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Hydro-Entangled, Single-Fiber Polymer
• A new material consisting of a hydro-entangled, single-fiber polymer based on
regenerated cellulose was developed.
• This fabric, which is completely synthetic, contains no natural fibers or binders.
• Under a microscope, the long, thin, hard fibers are identical and homogenous,
giving the fabric an open structure.
• The material is a pale, off-white color and highly absorbent.
• The fabric scores well on the solder paste pick-up tests for non-liquid
contamination.
• The fibers are smooth, consistent and hard.
• The paper includes extensive voids and cavities to pick up solder paste.
• There is no cellulose to rip or shred, or binders to dissolve and contaminate the
stencil.
Understanding the Cleaning Process for Automatic Stencil Printers
Paper Compared (Dry Wipe Data Only)
High End Paper Typical Paper Paper Using Glue
Base Weight (oz/per yd²) 1.87 1.56 1.11
Tensile Strength (LB’s) 29 31 16
Thickness (Mils) 15 12 11
Absorption (ML H²O/M²) 391 290 231
Fiber Shedding (particles >0.5
mm/m². x103)
127 1,130 20
Extractable IPA % 0.08% 0.07% 0.98%
Solder Paste Pick-up Test 77% 61% 33%
Understanding the Cleaning Process for Automatic Stencil Printers
Solvents
• Usage on solvents split down the middle with yes or no
• A NO to solvent is often based on a negative experience that can be traced to:
• Negative effect on the print process following solvent application
• Poor solvent performance
• Application method used
• Mismatch of solvent to printing material
• Misunderstanding of what solvents do
• Most common solvent used is Isopropyl Alcohol – which now has its issues
• Chemistry companies, prior to 7 years ago, did not understand the printing process and its requirements
• Often what was being recommended to be applied to the printer is also used to clean boards or stencils in a
tank
• Requirements of the print process and new chemistries have improved performance in the printer and have a
targeted this application
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Understanding the Cleaning Process for Automatic Stencil Printers