TECHNICAL DATA SHEET
285 Flux-Cored Wire
Mildly Activated Rosin Cored Wire for Leaded and Lead-free Alloys
Product Description
Kester 285 Flux-Cored Wire is a mildly activated rosin flux is classified as Type ROL0 flux under
IPC J-STD-004. This flux was formerly classified as Type RMA per QQ-S-571. 285 consists of
high quality, purified rosin to which a synergistic combination of activating agents has been
incorporated. The fluxing ability of 285 is much greater than ordinary mildly activated rosin
fluxes and is comparable to fully activated rosin fluxes. 285 has been developed for use in the
electronic industry where difficult assemblies are to be soldered, but process requirements
stipulate use of a mildly activated rosin flux.
Performance Characteristics:
Industry standard RMA cored wire
Compatible with leaded and lead-free alloys
Classified as ROL0 per J-STD-004
RoHS Compliance
This product meets the requirements of the Restriction of Hazardous Substances (RoHS)
Directive, 2011/65/EU for the stated banned substances. (Applies only if this core flux is
combined with a lead-free alloy.)
Reliability Properties
Copper Mirror Corrosion: Low
Tested to J-STD-004, IPC-TM-650, Method 2.3.32
Corrosion Test: Low
Tested to J-STD-004, IPC-TM-650, Method 2.6.15
Silver Chromate: Pass
Tested to J-STD-004, IPC-TM-650, Method 2.3.33
Chloride and Bromides: None Detected
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
285 Flux-Cored Wire
Technical Data Sheet
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TECHNICAL DATA SHEET
Surface Insulation Resistivity (SIR): Pass
Tested to J-STD-004B, IPC-TM-650, Method 2.6.3.7
Surface Insulation Resistivity (SIR), IPC (typical): Pass
Tested to J-STD-004, IPC-TM-650, Method 2.6.3.3
Blank
285
Day 1
1.0*1010 Ω
3.2*109 Ω
Day 4
9.5*109 Ω
7.7*109 Ω
Day 7
8.3*109 Ω
7.0*109 Ω
Spread Test (typical): Pass
Tested to J-STD-004, IPC-TM-650, Method 2.4.46
Area of Spread mm2 (in2)
Flux Core Solder
Cu
Ni
285
335 (0.52)
140 (0.22)
282
240 (0.37)
100 (0.16)
44
280 (0.43)
160 (0.25)
Availability
285 is available in a wide variety of alloys, wire diameters and flux percentages. For most
applications, Sn63Pb37 or Sn96.5Ag3.0Cu0.5 is used. Consult Kester’s website for the
comprehensive alloy list and for standard wire diameters. The standard wire diameter for most
applications is 0.8 mm (0.031 in). Wire diameters range from 0.25 to 6.00 mm (0.010 to 0.250
in). The amount of flux in the wire dictates the ease of soldering for an application. 285 is
packaged on spools of different sizes to accommodate a variety of applications.
Note: Core Size 50, 58 and 66 = 1.1%, 2.2% and 3.3% flux core.
285 Flux-Cored Wire
Technical Data Sheet
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TECHNICAL DATA SHEET
Process Considerations
Solder iron tip temperatures are most commonly between 315 to 371 °C (600 to 700 °F) for
Sn63Pb37 and Sn62Pb36Ag02 alloys and 371 to 427 °C (700 to 800 °F) for lead-free alloys.
Heat both the land area and component lead to be soldered with the iron prior to adding 285
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 and 186-18 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 as a Flux-Pen® for optimum board cleanliness.
Cleaning
285 flux residues are non-corrosive, non-conductive and do not require removal in most
applications.
285 Flux-Cored Wire
Technical Data Sheet
Issue: 17 May 2021
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TECHNICAL DATA SHEET
Recycling Services
We provide safe and efficient recycling services to help companies meet their
environmental and legislative requirements and at the same time, maximize
the value of their waste streams.
Our service collects solder dross, solder scrap, and various forms of solder
paste waste. Please contact your local sales representative for recycling
capabilities in your area or link here.
Storage, Handling and Shelf Life
Storage must be in a dry, non-corrosive environment between 10 to 40 °C (50 to 104 °F). The
surface may lose its shine and appear a dull shade of grey. This is a surface phenomenon and
is not detrimental to product functionality. Flux-cored solder wire has a shelf life determined by
the alloy used in the wire. For alloys containing more than 70% lead, the shelf life is 2 years
from the date of manufacture. Other alloys have a shelf life of 3 years from the date of
manufacture.
Health and Safety
This product, during handling or use, may be hazardous to your health or the environment.
Read the Safety Data Sheet and warning label before using this product. Safety Data Sheets
are available at this link.
Contact Information
To confirm this document is the most recent version, please contact
Assembly@MacDermidAlpha.com
North America
109 Corporate Blvd.
South Plainfield, NJ 07080, USA
1.800.253.7837
Europe
Unit 2, Genesis Business Park
Albert Drive
Woking, Surrey, GU21 5RW, UK
44.01483.758400
Asia Pacific
8/F., Paul Y. Centre
51 Hung To Road
Kwun Tong, Kowloon, Hong Kong
852.3190.3100
Also read carefully warning and safety information on the Safety Data Sheet. This data sheet contains technical information required for safe and economical operation of this product. READ IT THOROUGHLY
PRIOR TO PRODUCT USE. Emergency safety directory assistance: US 1 202 464 2554, Europe + 44 1235 239 670, Asia + 65 3158 1074, Brazil 0800 707 7022 and 0800 172 020, Mexico 01800 002 1400 and (55)
5559 1588
DISCLAIMER: All statements, technical information and recommendations contained herein are based on tests we believe to be reliable, but the accuracy or completeness thereof is not guaranteed. No
statement or recommendation shall constitute a representation unless set forth in an agreement signed by officers of seller and manufacturer. NO WARRANTY OF MERCHANTABILITY, WARRANTY OF FITNESS
FOR A PARTICULAR PURPOSE OR ANY IMPLIED WARRANTY IS MADE. The following warranty is made in lieu of such warranties and all other warranties, express, implied, or statutory. Products are warranted to
be free from defects in material and workmanship at the time sold. The sole obligation of seller and manufacturer under this warranty shall be to replace any noncompliant product at the time sold. Under no
circumstances shall manufacturer or seller be liable for any loss, damage or expense, direct, indirect, incidental or consequential, arising out of the inability to use the product. Notwithstanding the foregoing, if
products are supplied in response to a customer request that specifies operating parameters beyond those stated above, or if products are used under conditions exceeding said parameters, the customer by
acceptance or use thereof assumes all risk of product failure and of all direct, indirect, incidental and consequential damages that may result from use of the products under such conditions, and agrees to
exonerate, indemnify, defend and hold harmless MacDermid, Incorporated and its affiliates therefrom. No suggestion for product use nor anything contained herein shall be construed as a recommendation to
use any product in a manner that infringes any patent or other intellectual property rights, and seller and manufacturer assume no responsibility or liability for any such infringement.
© 2019 MacDermid, Inc. and its group of companies. All rights reserved. “(R)” and “TM” are registered trademarks of MacDermid, Inc. and its group of companies in the United States and/or other countries.
285 Flux-Cored Wire
Technical Data Sheet
Issue: 17 May 2021
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