What Platinum-Cured Silicone Actually Is | RUUIPON

Platinum-cured silicone (addition-cure, platinum-catalyzed RTV) is a two-part rubber that crosslinks when a platinum catalyst in one part meets vinyl/hydride groups in the mix. Mix is 1:1 or 10:1 by weight, by grade. After a full cure, linear change is typically about 0.1–0.3%. That sentence is chemistry. It is not a food-contact stamp, not 21 CFR 177.2600, not LFGB, and not "FDA approved factory." You still name the article test and the wash SOP if the cavity will see food.

RUUIPON pours platinum RTV tools in Bao'an / Shajing since 2018. Prototype 3–7 business days after CAD lock. Production MOQ 20 pieces per design. Simple 3D is USD $50 when that CAD scope applies. HCR peroxide vs platinum *parts* in steel are a different plant — wydsilicone.com.

Does not apply when you are buying an LSR baby nipple and you need a medical-device dossier. We do not invent ISO 13485 or device claims here. It also does not apply to tin-cure (condensation) kits labeled "silicone" on a craft aisle.

Addition-cure is a reaction, not a certificate

In the cup: weigh A and B, fold, vacuum until foam collapses, pour. The catalyst is sensitive. Sulfur clay, some SLA prints, tin residue, amines, and latex can leave the face tacky while the back cures — inhibition. That is why we seal masters and patch-test. Tin-cure uses a tin salt and gives off byproducts; it is more tolerant of dirty masters and it keeps moving in storage.

What platinum-cured does not mean:

• The factory is FDA-approved.
• The mold is automatically 177.2600-compliant.
• There is a jewelry-level of metal in the rubber (see does it contain platinum).
• Higher Shore, or "professional" versus 1:1 hobby.

What it does mean for a mold buyer: low leftover odor versus tin, a shrink band you can recast against, and a food path that is *possible* if you also do documents and wash. Chart the dump on best silicone by pour.

flowchart TD
  A[Need an RTV tool] --> B{Food-contact article?}
  B -->|yes| C[Platinum + article docs + wash]
  B -->|no| D{Library size and low odor?}
  D -->|yes| C
  D -->|dirty short run| E[Tin may be honest]
  C --> F[Seal master; mix 1:1 or 10:1 by weight]

The photo that would prove the claim: TDS line that says addition-cure / platinum catalyst next to a packing list that names 177.2600 extraction on the article. A hang-tag that only says "platinum silicone" proves marketing.

Peroxide-cured HCR on a mill is another platinum-adjacent confusion. That is a *part* compound on a steel tool, often with a post-cure oven. RTV platinum on this site is a room-temperature (or mild-oven) pour against a master. Do not write "platinum silicone" on a PO and expect us to know which plant. If the silicone *is* the product, the RFQ leaves for wydsilicone.com.

Clear platinum trays yellow in UV; that is aging of the polymer, not "the platinum coming out." Do not chase yellow with a metal cleaner. Store dark. Odor on a new platinum tool should be quiet versus tin; a sharp vinegar smell usually means you are not on addition-cure, or someone cleaned the cavity with acetic caulk residue. ISO 3302-1 M2 is a rubber drawing class. It does not certify the catalyst.

What the catalyst does not certify

Buyers paste "platinum-cured = food safe" into the PO. Food safe is extractives on the finished article, plus your use temperature and media. We would not skip that pack because the drum was platinum. We would not pour tin on a chocolate tray because platinum "sounds medical."

CBD/THC: tooling only. Platinum does not make a dose.

Read the TDS family, then run a lid patty

Read the TDS: addition-cure, mix ratio by weight, inhibition notes. Run a lid patty. If the job is food, pack the article test names you need — we do not invent SGS report numbers. Witness dump after full cure; size vs 0.1–0.3% band.

Shop numbers for platinum RTV tools

Caption: typical shop values, not a named PO.

Claims we would not print

We would not recommend "platinum-cured" as a substitute for 177.2600 / LFGB on a food RFQ.

We would not recommend platinum against an unsealed SLA "because platinum is better."

We would not recommend mixing leftover tin into a platinum cup.

We would not recommend calling QMS ISO 9001 a food stamp. (WYD holds a QMS number; RUUIPON's job here is the RTV tool.)

A tooling charge is not unrestricted ownership of the TDS or the master. If your copacker changes the dump media (hexane vs water extractives, or a hotter fill), that is a new article conversation, not a free reprint of the word platinum.

Inhibition is still the shop failure that looks like "bad platinum." Face tacky, back cured, lid patty fine: seal the master. Do not throw the drum because a website said platinum never fails.

Worked example: chocolate tray that still needed the pack

Chocolate bar tray, buyer wrote "platinum-cured, so no docs needed." We still quoted platinum 25A open-back, wash SOP, and the article extraction names they must have for their copacker. Prototype 3–7 business days after CAD lock. $50 3D did not apply. MOQ 20 per design. The drum was platinum; the pack was still a pack.

Mix-up: platinum-cured means FDA approved

Catalyst family versus article test. The other mix-up is platinum-cured versus medical-grade versus 10993 — different stacks, different RFQs, often a parts quote not a mold quote.

Questions that unmix the word platinum

• Dump family and food-doc names you actually need?
• Master chemistry (SLA, clay, metal)?
• 1:1 or 10:1 if you spec a grade?
• Library recast, unsanded master custody?
• Is this a mold you pour into, or a silicone *part*?

Related: platinum vs tin, contact.

RFQ copy-pack — platinum as chemistry

Paste into [email protected]:

Object: platinum RTV mold I pour into, not an LSR/HCR part Dump and peak °C Food path: 177.2600 / LFGB / BfR XV / craft-only Master type and sealer / UV status Mix: 1:1 or 10:1 by weight if you spec a drum File: STEP / STL / photos with a millimetre scale CAD: mold-ready STEP OR USD $50 3D if that scope applies Prototype 3–7 business days after CAD lock, then MOQ 20 per design Do not treat "platinum-cured" as a food stamp

Send dump and doc names. We pour addition-cure — not a blank "free quote." Phone +86 135 3006 2969. Licheng Technology Industry Park, Xinhe Blvd, Shajing, Bao'an. Shop since 2018.

FAQ

Is platinum-cured the same as food-grade? No. Platinum is the catalyst family. Food-contact is documents on the article plus use conditions.

Is it the same as medical-grade? No. Medical stacks (when they apply) live on a parts RFQ with different docs. Do not mix them on a candy tray PO.

Why do I still seal the master? Platinum inhibits against sulfur, some prints, tin residue. Catalyst quality does not delete that.

Does platinum-cured shrink less than tin? Typical platinum band after full cure is about 0.1–0.3% and then holds. Tin keeps moving in storage.

If I pay for platinum tooling, can I skip LFGB? A tooling charge does not buy a market approval. Name the tests you need on the article.