Kester 44 Data Sheet

44

44

Activated Rosin

Activated Rosin

Cored W

Cored W

ire

ire

Product Description

Kester 44 Rosin Flux is an activated rosin formula
for use in flux-cored solder wire. Kester 44 Rosin
Flux has virtually dominated the field of activated
rosin core solders for well over four decades. An
outstanding performance feature of this flux is the
"instant-action" wetting behavior. The high mobility
and fast-spreading action of this flux result s in
more reliable production line soldering.

Performance Characteristics:

• High activity RA formulation

• Excellent solderability to a wide variety of
metallizations

• Industry standard RA cored wire for decades

• Classified as ROM1 per J-STD-004

Reliability Properties

Copper Mirror Corrosion: Moderate

Tested to J-STD-004, IPC-TM-650, Method 2.3.32

Corrosion Test: Moderate

Tested to J-STD-004, IPC-TM-650, Method 2.6.15

Silver Chromate: Fail

Tested to J-STD-004, IPC-TM-650, Method 2.3.33

Chloride and Bromides: 0.44%

Tested to J-STD-004, IPC-TM-650, Method 2.3.35

Fluorides by Spot Test: Pass

Tested to J-STD-004, IPC-TM-650, Method 2.3.35.1

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Application Notes

Availability:

Kester 44 is available in a wide variety of alloys, wire diameters and flux percent ages. For most applications,
Sn63Pb37. Consult the alloy temperature chart in Kester ’s product catalog for a comprehensive alloy list.
The st andard wire diameter for most applications is 1.00mm (0.031in). Wire diameters range from 0.25-

6.00mm (0.010 to 0.250in). A "Standard Wire Diameters" chart also is also included in Kester’s product catalog.
The amount of flux in the wire dictates the ease of soldering for an application. For most applications, core
66 (3.3% flux by weight) is recommended. Other core sizes, 50 and 58, (1.1% and 2.2% respectively) are
available. Kester 44 is p ackaged on spools of different sizes to accommodate a variety of applications.

Process Considerations:

Solder iron tip temperatures are most commonly between 315-371°C (600-700°F) for Sn63Pb37 and
Sn62Pb36Ag02 alloys. Heat bot h the land area and component lead to be soldered with the iron prior to
adding Kester 44 cored wire. Apply the solder wire to the land area or component lead. Do not apply the
wire directly to the soldering iron tip. If needed, Kester 186 Mildly Activated Rosin Flux may be used as a
compatible liquid flux to aid in reworking soldered joints. Kester 186 Mildly Activated Rosin Flux is also
available in Flux-Pens

Cleaning:

Kester 44 possesses excellent fluxing ability, the flux residue is non-corrosive and non-conductive under normal
conditions of use. When exposed to an elevated temperature and humidity environment (38°C, 94% RH) for
72 hours, there is no evidence of corrosion caused by the flux residue. Throughout its many years of wide
usage, 44 Rosin Flux has produced many billions of soldered connections. In all these billions of solder
joints, involving the most delicate and critical of electrical and electronic components, there has never been
an authentic instance of corrosion by the flux residue under normal conditions of use. This mild property of
the residue permits leaving the flux on the assembly for many applications.

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for optimum board cleanliness.

Storage, Handling, and Shelf Life:

Storage must be in a dry , non-corrosive environment. The surface may lose it s shine and appear a dull
shade of grey. This is a surface phenomena and is not detrimental to product functionality. Flux cored solder
wire has a limited shelf life determined by the alloy used in the wire. For alloys cont aining > 70% lead, the
shelf life is two years from date of manufacture. Other alloys have a shelf life of three years from date of
manufacture.

Health & Safety:

This product, during handling or use, may be hazardous to health or the environment. Read the Material
Safety Data Sheet and warning label before using this product.