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Marking Ink Suitable for Use in Circuit Card Assembly Process

IP.com Disclosure Number: IPCOM000119918D
Original Publication Date: 1991-Mar-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 2 page(s) / 60K

Publishing Venue

IBM

Related People

Fujiuchi, S: AUTHOR [+3]

Abstract

Disclosed is a marking ink which is easy to remove after UV curing or soldering and does not contaminate cleaning solvents.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Marking Ink Suitable for Use in Circuit Card Assembly Process

      Disclosed is a marking ink which is easy to remove after
UV curing or soldering and does not contaminate cleaning solvents.

      The circuit card assembly process involves various steps, such
as soldering, visual inspection, function test, repair and cleaning.
The process includes some soldering steps, and visual inspection is
usually done between the soldering steps.  Locations found defective
by the inspection are marked by a marking ink for repair.  However,
commercially available inks tend to be cured under heat for UV curing
or soldering, which makes removal of the inks difficult.  If the
marked ink is not removed or cleaned completely, it might affect
reliability of the card.  Also, such marking inks should not
contaminate the cleaning solvent.

      To meet the above requirements, this disclosure proposes a new
marking ink which comprises the following ingredients:
         Rosin              40 - 80 %
         Thickener           1 - 20 %
         Organic Solvent    10 - 50 %
         Pigment           0.5 - 20 %
Rosin is the main ingredient, and any suitable known rosins, such as
polymerized rosin or disproportionated rosin, may be used.  Thickener
is added to adjust viscosity of the ink. For example, hydrogenated
castor oil may be used therefor. Organic solvent is added to
facilitate dispensing.  For example, butyl carbitol or ethylene
glycol monophenyl ether may be used.  Pigment is added to provide
colo...