| Plating Chemicals |
| Market Overview |
| Introduction |
Plating chemicals encompasses a broad spectrum of surface
finishes on materials that impact almost every part of technology
and our daily lives. Varsal has made a major impact in recent years
on the plating of electronic components as a leading producer of Methane
Sulfonic Acid 70%. Below are listed some other major plating applications
that utilize Varsal products:
- Automotive trims and engine components
- Aircraft parts
- Kitchen & Bathroom fixtures
- Jewelry
- Surgery tools
|
| Types of Plating |
There are two main types of plating called electrolytic
and electroless. The electrolytic or electroplating process involves
the coating of an object with a thin layer of metal by use of electricity.
Electroless plating also involves coating an object with a thin layer
of metal but as its name implies, does not use electricity. The electroless
process is purely chemical and runs by itself once started. Both processes
are used for different applications depending on the substrates to
be plated, required properties of the plated surface, and cost considerations.
Sometimes combinations of both processes are required for example
on plastic. Since plastic is not conductive then a metal layer is
deposited using the chemical process or electroless. Once a conductive
layer is applied then an electrolytic process can be used to deposit
a different metal coating.
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| Varsal Main Plating Chemicals |
Some of the main plating chemicals produced by Varsal to be discussed
are as follows:
- Methane Sulfonic Acid 70%
- Tin (II) Methane Sulfonate Solution
- Lead (II) Methane Sulfonate Solution
- Lead (II) Methane Sulfonate Solution (Low Alpha)
- Copper (II) Methane Sulfonate Solution
- Bismuth Methane Sulfonate Solution
- Silver Methane Sulfonate Solution
- Nickel (II) Methane Sulfonate Solution
- Sodium Hypophosphite Monohydrate
|
| Products/Applications |
| High Speed Electronics Plating with MSA Chemistry |
Methane Sulfonic Acid plating chemistry has been established as
a dominant electrolytic plating process for high speed reel-to-reel
processing of electronic components. Components are fastened to long
tapes that are wound onto a reel. The reel unwinds and the tape with
components is pulled through the plating tanks and then is wound back
up on a second reel. (Pct. 1) The plating bath solution consists of
MSA 70%, Tin (II) and Lead (II) Methane Sulfonate solution, and plating
additives. Most of the components have wire leads sticking out which
are usually bent and inserted into plated holes on printed circuit
boards. These leads or lead frames are electroplated with Tin or Tin-Lead
alloys. The resultant plated Tin-Lead surface is easy to solder to.
The most important factor is that the solder plating bonds on the
printed circuit board have long life and do not corrode. Such corrosion
could cause an electronic device to fail and possibly cause a loss
of life.
Varsal MSA 70% provides the following advantages for electronic plating:
- Approved for use in all major tin-lead applications
- Low odor with Varsal DMDS process
- Low oxidizables, and chlorides ensure long life, stable solder
deposits.
- Promotes "Green Chemistry" with less environmental impact from
sludge.
- Provides superior throwing power to allow high-speed tin-lead
alloy plating in reel-to-reel operations.
- One stop shop package includes MSA 70% and a variety of Tin
and Lead MSA salts.
- Global supply to customers with multiple worldwide manufacturing
sites.
|
| Varsal MSA salts for the future |
Varsal is actively involved in the production of MSA salts for various
plating processes including R&D for future lead free plating.
As described, current electronic plating utilizes various proportions
of tin and lead salts provided by Varsal as Tin (II) and Lead (II)
Methane Sulfonate Solutions. There are worldwide efforts to remove
lead from the electronic plating process and Varsal has developed
other MSA salts such as bismuth and copper. “Low Alpha?lead by its?
name emits less radioactive alpha particles to lessen potential damage
to sensitive memory chips. Some other specific applications require
silver plating in high heat automotive engine contacts.
Varsal provides the following advantages for MSA salt chemistry:
- A selection of common Tin, Lead salts: Tin, 300 and 400 g/L;
Lead, 450 and 500 g/L.
- Varies free acid content of Sulfonate solutions for specific
plating tank requirements.
- Offers alternative salts such as Bismuth and Copper for lead
free process technology.
- "Low Alpha" lead for sensitive electronic semiconductor applications.
- Produces Silver Methane Sulfonate Solution for high heat automotive
applications.
|
| MSA Chemistry Product Selection Guide. |
| Product |
CAS No. |
Description |
Application |
| Methane Sulfonic Acid 70% |
75-75-2 |
Electrolyte for Methane Sulfonic Acid (MSA) plating bath |
High Speed Reel-to-Reel strip plating |
| Tin (II) Methane Sulfonate Solution, 300 g/L |
53408-94-9 |
Most commonly used Tin solution |
Tin, Tin Alloy reel -to-reel baths |
| Tin (II) Methane Sulfonate Solution, 300 g/L, Low Acid |
53408-94-9 |
Tin-MSA salt solution with lower "free acid" |
Reduce "free acid" build up with insoluble anode |
| Lead (II) Methane Sulfonate Solution, 450 g/L |
17570-76-2 |
Old standard lead solution |
Tin-Lead plating |
| Lead (II) Methane Sulfonate Solution, 500 g/L |
17570-76-2 |
New standard concentrated lead solution |
Tin-Lead plating |
| Lead (II) Methane Sulfonate Solution, 500 g/L, Low Alpha |
17570-76-2 |
Lead solution utilizing low alpha particle lead |
Sensitive semiconductor plating to prevent errors |
| Copper (II) Methane Sulfonate Solution, 100 g/L |
54253-62-2 |
Copper MSA salt |
Used in new lead-free solutions and R&D |
| Bismuth (III) Methane Sulfonate Solution, 150 g/L |
N/A |
Bismuth MSA salt |
Used in new lead-free solutions and R&D |
| Silver (I) Methane Sulfonate Solution, 200 g/L |
55136-38-4 |
Silver MSA salt |
Used for high heat environment plated surfaces |
|
| Electroless Nickel Plating with Varsal
Sodium Hypophosphite |
Discovered in 1946, electroless nickel is one of the
major electroless plating processes utilized by industry. This plating
process is used for many applications including hard disk media, electronic
connector and lead frames, automotive engine parts, bathroom fixtures,
and ball point pen refills.
A simple electroless nickel process is described as:
3NaH2PO2 + 3H2O + NiSO4
→ 3NaH2PO3 + H2SO4
+ 2H2 + Ni0 (6)
The typical solution is made up with two major ingredients: a reducing
agent, Sodium Hypophosphite (NaH2PO2) and the
nickel source, Nickel Sulfate (NiSO4). |
| High Purity Varsal Sodium Hypophosphite
|
| Varsal produces a high purity, electroless nickel grade,
sodium hypophosphite monohydrate. By listening to customer demands
regarding various applications, Varsal specifications meet most major
electroless nickel applications. For example, customers require low
calcium for demanding hard disk media applications; the Varsal product
has standard lower than 10 ppm calcium, to result in a smooth coating. |
| Varsal Electroless Products for the
Future |
There is a worldwide effort to prolong the life of an
electroless nickel bath while maintaining the quality of the plating
deposit. For one approach Varsal produces Nickel Hypophosphite, which
is used in place of Sodium Hypophosphite. Another method utilizes
Nickel Methane Sulfonate solution (Nickel MSA salt)
Varsal Advantages for Electroless Nickel Plating:
- High purity Sodium Hypophosphite low in lead and heavy metals.
- Over-dried to yield >101% assays for free-flowing consistency.
- Low calcium < 10 ppm for smooth coating.
- Nickel Hypophosphite and Nickel MSA for new long life bath formulation
R&D.
- Global support for customers with multiple locations worldwide.
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