SSO3 is the short name for sodium 2-hydroxy-3-mercaptopropanesulphonate, a sulfur-bearing organic sulfonate supplied as a colorless to yellow liquid with a pH between 1.0 and 4.0. In a plating shop it is a small-dose addition to nickel baths — the kind of component that never appears in a headline but quietly decides how consistently the bath behaves across a production week.
It is an additive, not a process. The nickel source, reducer, complexing agents and pH control still do the main work of an electroless nickel plating solution; this product works alongside them, improving covering power and tolerance to the metallic impurities that every working bath collects.
Fitting it into the electroless plating process takes no new equipment and no change to the line sequence. It is weighed, dissolved and added to the working bath, then topped up as the bath consumes it — the same routine as any other liquid addition on the aisle.
Buyers comparing one electroless nickel plating company with another tend to ask the same few things: how wide the working window is, what this does that a brightener does not, and how much of a drum actually ends up doing useful work. The answers are practical rather than theoretical, which is why we write dosing in grams per tank rather than in percentages.
| Chemical name | Sodium 2-hydroxy-3-mercaptopropanesulphonate |
| Synonym | SSO3 |
| CAS No. | 20055-98-5 |
| Molecular formula | C3H7NaO4S2 |
| Molecular weight | 194.20 |
| Appearance | Colorless to yellow liquid |
| Density, g/cm³ (20 °C) | 194.20 |
| pH | 1.0–4.0 |
| Function | Covering power and impurity tolerance agent in nickel baths |
| Typical addition | 10–50 mg/L |
| Standard | Confirmed to enterprise standard |
| Pack | 25 kg/drum |
Smoother, more uniform deposits. Fewer pits, fewer thin patches and less polishing after plating. For a shop that sells electroless nickel plating services, that translates into fewer rework claims and a quotation that holds.
Nickel where it counts. Covering power is what lets a deposit reach its target plating thickness in recesses and low-flow areas, instead of over-plating the flats so the recesses creep into specification.
Corrosion protection that lasts. A dense, continuous layer leaves fewer pores for moisture and salt to attack, and pore count is where the corrosion performance of a nickel deposit is really decided — not in the thickness number alone.
Easier on people and on the waste stream. The product is non-toxic as supplied and formulated to keep environmental impact low, so handling stays within ordinary plating-shop practice and the effluent load stays manageable alongside the rest of the line.
Consistent from drum to drum. Made to a fixed enterprise standard, so the addition level you settle on during the trial behaves the same way three months later, on a different lot, in a different operator's hands. The range is designed to be eco-friendly, minimising environmental impact while still maintaining high efficiency and effectiveness.
Why aluminum is unforgiving. Aluminum carries an oxide film that re-forms within seconds of being removed, and the aluminum–nickel couple is galvanic. Get it wrong and the deposit blisters, peels at the edges or fails after a thermal cycle — long after the parts have left the shop.
What changes with this additive. For electroless nickel plating on aluminum, the difficulty is starting deposition evenly on a surface that is chemically uneven. Dosing this product improves how uniformly the nickel initiates and builds, so the layer runs continuous across the part instead of heavy in some zones and thin in others.
Pretreatment still decides most of it. Degreasing, etching, desmutting and activation are where aluminum work is won or lost, and the electroless nickel plating process rewards a consistent sequence more than a higher addition rate. If you are setting up a new aluminum line, send us the sequence and we will tell you where the risks usually sit.
Uniform plating thickness on complex shapes. Extrusions, castings and machined housings rarely have an even surface. A bath with good covering power puts a more consistent plating thickness across the part, which matters when the drawing calls for a minimum layer deep inside a recess.
Rack or barrel. Small parts run well in barrels, where tumbling exposes every face to the bath; larger parts stay on racks. The addition level is the same either way — only the handling and the inspection points change.
| Pack for this product | 25 kg/drum |
| Pack formats in the range | 10 kg/box; 25 kg or 50 kg/bag; 20 kg/25 kg/30 kg/200 kg/drum; 1000 kg/IBC drum |
| Minimum order quantity | Varies by chemical; confirmed with our sales team per order |
| Lead time | 2 weeks |
| Payment | 100% T/T in advance |
| Shipping | Per the terms agreed in the current contract |
| Documentation | Inspection certificate issued after delivery, stating the batch number and warranty period |
| Samples | Ask your sales contact about availability for a bath trial |
| Custom requirements | Packing, labelling and document sets agreed with the sales team per order |
| Storage | Cool, dry place, drum kept closed between additions |
With over 20 years in the industry, we bring deep knowledge and hands-on expertise to every project, from first specification through to delivery.
Choosing the right match is where most sourcing decisions stall. As a trading supplier, we keep one point of contact from first enquiry to after-sales: tell us what you are making and the conditions you work under, and we shortlist the closest matches from our supplier network, compare specifications and arrange samples before you commit to a bulk order. If something does not behave as expected, we work with the supplying partner on the cause and a practical fix, and stay with the case until it is settled. Email, WeChat or WhatsApp enquiries get a reply within 24 hours.
Two jobs, both at very low dose. It improves covering power, so the nickel reaches blind holes, threads and the inside of a barrel load instead of thinning out there. It also raises the level of metallic impurity the bath tolerates before the deposit darkens or loses adhesion. Inside an electroless nickel plating solution it is a functional addition rather than a main component — the nickel source and the reducer still do the plating.
Start at the bottom of the 10–50 mg/L window and confirm the result on a trial part before moving up. Most lines then top up on bath analysis rather than on a fixed schedule, because consumption follows drag-out and throughput. As with other electroless nickel plating chemicals, the number on the data sheet is a starting point, not a target to hit blind.
Yes — aluminum is where most buyers notice it first. The oxide film re-forms immediately and the aluminum–nickel couple is galvanic, so an even start is what keeps the layer continuous through thermal cycling and handling. If you are moving from steel to aluminum on the same line, check the activation step before you change the addition level.
No. The electroless nickel plating process stays as it is: same tank, same make-up order, same filtration loop. The additive is weighed, pre-dissolved and added to the working bath, then topped up as it is consumed. If your bath runs a proprietary brightener system, tell us which one and we will confirm the working point with you.
The additive does not set the deposition rate — time, temperature, pH and the nickel-to-reducer balance do. What it changes is where that thickness lands: with better covering power, the target plating thickness is reached in recesses as well as on the flats, instead of over-plating the flats to bring the recesses into specification. Set the rate from your bath, then use the additive to make it even.
Keep it closed in a cool, dry place. The liquid is acidic at pH 1.0–4.0, so gloves and eye protection belong on when you weigh it out, and a dedicated clean scoop stops contamination travelling back into the drum. At these dose rates one drum covers a long production run, so storage conditions matter as much as the addition itself.
