J-STD-004B:

A New Twist on an Old Standard

Ales Sedlak

Outline/Agenda

Introduction

How Are Flux Properties Established

How Are SIR Values Tested

What Has Changed

Things You Should Know

Conclusion

Q & A

Introduction

Solder flux used in electronics

production have been a constant

evolution

Since the earliest electronics

assemblies rosin has been a

component of electronic soldering

fluxes

How Are Flux Properties

Established?

J-Std-004 and now J-Std-004B Updated in 2008

Manufacturer compliance is voluntary

Many new products still refer to the -004A

standard

Letter Designators

Flux Composition RO - ROsin

RE - REsin

OR - ORganic

IN - INorganic

Flux Residue Activity

Levels

Understand the Subtle Differences

Between Rosin and Resin

The terms are often used interchangeably, but rosin is a

naturally occurring substance, and resin is either a

modified rosin or completely synthetic material.

Rosins are tree products and are subject to more natural

variation than resins; resins are commonly used in newer

flux formulations due to their more consistent

performance and tailored properties

When more than one rosin/resin are combined, the IPC

classification is based on the larger constituent.

Therefore, if the distinction between RO and RE is

important to the user, they should inquire with the flux’s

manufacturer to better understand the exact details of the

content and classification criteria.

How Are Flux Properties

Established?

How Are (S)urface (I)nsulation

(R)esistance (SIR) Values

Tested?

Effect of Ionic Compounds

Dendrite Formation

B-24 Coupon Corrosion

ACID A ACID B ACID C

ACID D ACID E

J-Std-004 v -004B

What has Changed?

J-Std-004 v -004B

What has Changed?

J-Std-004 v -004B

What has Changed?

J-Std-004 v -004B

Comparing SIR Results

J-Std-004B

IPC 2.6.3.7 J-Std-004

IPC 2.6.3.3

IPC Designation

IPC-TM-650 method 2.3.28.1 for halide

Determined halogen/halides are back

calculated to the solids content of the flux

Chromatography Data for Liquid

Flux

Chromatography Data for Liquid

Flux

Low solids fluxes are hyper sensitized by

having a low solids content

This causes many liquid fluxes to be

classified as L1 although they are truly not

Things You Should Know

Know The Relationship Between

Halides and Halogens

Halides are ionic compounds typically used as activators

and are often associated with corrosion. Specification of

testing methods and thresholds for halide content are

addressed by IPC J-Std.-004/004B

Non-ionic halogenated compounds, or halogens, are the

subject to REACH regulations. Specification of testing

methods and thresholds for halogen content are addressed

by European Environmental Standards - EN-14582.

THIS IS AN ENVIRONMENTAL SPECIFICATION –

NOT A RELIABILITY SPECIFICATION.

Halogens in Paste

Halogen vs. Halide

When a halogen takes one electron, it becomes a

halide

Br + e Br-

This causes the halogen to become a halide and is

very reactive

List of Halogens

(F) Fluorine

(Cl) Chlorine

(Br) Bromine

(I) Iodine

(At) Astatine

Why Halogens?

These compounds are effective fluxing

agents therefore less activation from

organic acids is required in a flux formula

Halogen compounds are thermally stable

providing longer exposure time and a

bigger process window

They are cost effective and can be easily

incorporated to flux chemistry

Halogens

Are Neutral in charge – non-ionic

Enhance soldering when used in flux

The most common use is in fire retardants

for PCB laminate and in this capacity are

the subject of REACH regulation

Halides

Ionic, hydrophilic and can create

conductive pathways

Typically used in strong organic acid or

inorganic acid flux

Used for etching in circuit board assembly

What Classification is Your

Flux Today?

Fluxes older than 2008 are exempt from the

new regulations and do not have to meet the

specification of -004B

When trying to replace them do not compare J-

Std.-004 designators – they are not equal.

A flux classified as ORL0 under -004 is very

possibly an ORL1 under -004B

J-Std.-004A flux can contain much more

halide as a -004B flux and still be considered

‘halide-free’.

Applying the Changes in Flux

Designators to Your Process

Does your flux choice suit your application process

requirements

This is especially critical in liquid flux

Liquid flux is typically designed for wave

soldering

Specific fluxes should be used in consideration of

the application method.

Liquid Flux Processing

What About:

Selective

Rework

Wave with palletized boards

What If Your Flux Is Not

Properly Heated?

Flux Surface Insulation Resistance

SIR test, the flux is heated

Pre-2008 VOC free flux formulas may not pass the

new SIR 2.6.3.7

Are you running a process that guarantees all liquid

flux is heated?

Flux ‘deactivation’ is time/temperature dependent

Conclusion

IPC J-STD-004B is a continually evolving

specification

It is important for the Engineer specifying the

materials to understand the requirements for their

product type

IPC J-STD-004B may not always fit all assembly

requirements

Spacing, signal type, board materials and application

methods can all affect the path of material sets

specified

Q & A

Questions?

Thank You

Revision A