Electronic Specialty Gases in the Group's Range: the CAS List and How They Are Specified
· HANGRUI HOLDINGS LIMITED
A specialty gas is bought by substance and grade, not by brand: a CAS number fixes the substance, the specification sheet fixes the impurity limits, and a certified pressure container gets it to the line. This page is the group’s reference list — the four fluorinated electronic specialty gases in the group’s range, and the discipline that applies to each. The group’s operating companies source from qualified producers, consolidate the order and hand over the document set; they are not manufacturers.
Which gases are in the group’s range?
Four fluorinated substances. Each row is one defined substance with one CAS number — not a blend, not a family.
| Product (systematic name, formula) | Designation | CAS | Typical packages | Principal uses | Notes |
|---|---|---|---|---|---|
| Tetrafluoromethane (carbon tetrafluoride, CF₄) | R-14 / PFC-14 | 75-73-0 | Individual cylinders, bundles, Y-cylinders; ISO container where volume justifies it | Plasma etching of dielectric films; chamber cleaning | UN 1982. “R-41” is not this substance — see the note below |
| Hexafluoroethane (perfluoroethane, C₂F₆) | R-116 | 76-16-4 | Individual cylinders and bundles | Plasma etch and chamber-clean process gas; wafer processing | UN 2193; EC 200-939-8 |
| Octafluorocyclobutane (perfluorocyclobutane, C₄F₈) | R-C318 | 115-25-3 | Individual cylinders, bundles, Y-cylinders | Etch steps where a fluorocarbon polymer film does the work (dielectric etch, sidewall passivation) | UN 1976; EC 204-075-2 |
| Hexafluoropropylene (hexafluoropropene, C₃F₆) | R-1216 | 116-15-4 | Individual cylinders and bundles | Monomer and intermediate for fluoropolymers and fluorochemicals; also plasma/etch work | UN 1858. Reactive, shipped as a stabilised liquefied gas — read the SDS before designing the receiving system |
Designation note. Designation numbers travel by habit, not by rule. R-41 is not R-14: R-41 is fluoromethane, CH₃F, CAS 593-53-3, while tetrafluoromethane is R-14, CAS 75-73-0. A request written “R41” cannot be filled as tetrafluoromethane. When a designation and a name sit in the same line of an email, check both against the CAS before the enquiry becomes an order.
What makes a fluorocarbon an “electronic specialty gas”?
The formula is not the difference — the specification is. The same molecule sold as an industrial or refrigerant gas and the same molecule sold for a fab differ in the impurity limits they are held to, the analysis run against them, and the container service they are packed in.
SEMI C3, Specification for Gases, shows how such limits are written: content limits in mole/mole, the assay for a major component as a minimum permissible limit and each impurity as a maximum. A gas beating the minimum assay is not “better” than the specification — it is the same product.
- A grade is a list of limits, not one number. “Purity” alone does not say what is excluded; the limits that matter are those on the specification sheet, typically trace oxygen, moisture, carbon monoxide and dioxide, other halocarbons, and metals where the process is sensitive.
- The same CAS is bought at different grades — so the grade belongs in the purchase order, not in an assumption drawn from the product name.
Packages: what you are buying when you order a cylinder
A specialty gas order is two transactions at once — you buy the gas, and you take custody of a certified pressure container that has to come back.
| Package format | Typical trade form | Confirm before ordering |
|---|---|---|
| Individual cylinder | One cylinder, one gas; a 40–50 litre class pressure cylinder is common in this trade | Cylinder standard and last test date; valve outlet connection; returnable, and who pays the return leg |
| Cylinder bundle | Several cylinders on one frame with a common manifold | Frame marking and cylinder count; whether it ships and returns as one unit |
| Y-cylinder / tonner | A larger single container for higher-volume users | Handling equipment at destination; how the container is returned |
| ISO container / tube trailer | Bulk where the volume justifies the unit | Working pressure and T-code, cleaning status, free days, return or one-way terms |
Four points that decide whether the shipment works:
- The valve outlet is part of the product. A cylinder arriving with a fitting the receiving gas panel cannot take is a delay, not a delivery. Name the outlet connection needed (CGA, DISS, JIS, DIN or BS, by number).
- Fill is by mass, not volume. A liquefied gas is filled to a mass ratio that keeps the container from becoming liquid-full at the temperature the transport rules assume. A pressure reading says nothing about whether the mass is inside the limit; net weight (gross minus tare) is the verifiable quantity.
- Containers travel protected. The industry guide for this category (EIGA Doc 199 / AIGA 018) expects containers certified and periodically tested to national standards, valve protection fitted in transit, handling by trained personnel only, the SDS on hand and an emergency response plan at the receiving site.
- An empty cylinder is not empty. Returnable containers normally travel under positive residual pressure so air and moisture cannot enter the shell. The residual pressure required on the return leg belongs in the contract.
Documents: what should travel with the gas
| Document | Issued by | What it does — and does not — prove |
|---|---|---|
| Specification sheet | The producer | The limits for the product — not a result for a specific batch |
| Certificate of analysis (COA) | The producer’s laboratory, for the batch shipped | What that batch measured, per parameter. Batch number on the COA must match the cylinder |
| Safety data sheet (SDS) | The producer, in the format and language required for the destination | Classification, handling, exposure control, transport class, disposal. §14 carries the UN number and proper shipping name |
| GHS label + shipping papers | As required for the route | UN number and proper shipping name must be identical across SDS, label and transport documents |
| Export set (shipments out of China) | Producer and/or appointed agencies | Commonly the dangerous-goods classification and identification report, transport conditions appraisal certificate and packaging certificate, in addition to the SDS. Regulatory basis: State Council Decree No. 591 |
The group’s operating companies pass through the producer’s documents. They do not re-issue another laboratory’s COA, and they do not restate a producer’s limit as their own measurement. Every figure on a quotation comes from a document the buyer can read too, with the issuing entity named on it.
How to write the grade on a purchase order
A workable grade line has five parts, and it can be short:
- Substance + CAS — not the trade name alone.
- Grade basis — “conforming to the producer’s specification sheet [reference]” is normally the strongest route; alternatively name the framework (for example a SEMI C3-style specification).
- The critical impurities for the process, each with a maximum limit and test method.
- Test level — whether each cylinder, bundle or lot is analysed, and whether the batch COA must be supplied before shipment.
- Container requalification, and whether the gas needs a documented retest window in the buyer’s store.
If a limit cannot be evidenced, it should not be written: a number nobody will stand behind becomes the acceptance criterion. Where the buyer has no specification of its own, the operating company asks the producer for theirs and sends it before the buyer commits.
How to raise an enquiry
Send these and the quotation can be specific rather than indicative:
- Substance and CAS number (and the designation, if the request arrived in that form).
- Grade basis, and the impurities that matter to the process.
- Package format, cylinder count, and the valve outlet connection required.
- Returnable or one-way container, and whether the return leg must be costed.
- Destination port or receiving site, and whether the last leg involves inland dangerous-goods delivery.
- Documents required before shipment (specification sheet, COA, SDS language, certificates).
- Incoterm and quantity. MOQ is per substance and per package — it is quoted, not assumed.
All shipments move as dangerous goods under the rules in force for the route. The classification declared is the one in the producer’s SDS; it is not adjusted to make a booking easier, and a request to route around a dangerous-goods requirement cannot be accepted. The written enquiry route — the items that make a first quotation usable — is set out in how to request a quotation.
Which entity supplies
Electronic specialty gases are supplied by the group’s operating companies, each within its own licence scope:
- HARMONY TECHNOLOGY (ZHEJIANG) CO., LTD. — international trading; export markets, consolidation and documentation.
- RIBOLUO CHEMICALS (ZHEJIANG) CO., LTD. — the distribution line, publishing specifications at CAS level.
Which entity signs the contract, which appears on the dangerous-goods declaration and which holds the licence covering the product are three separate questions; they are set out in document consistency across a multi-entity supply chain and which Chinese licence governs which activity.
Related
- Sourcing chemicals from China: six checks before the first order — what a buyer can verify before committing.
- How to request a quotation — the items that make a first quotation usable.
- Vetting a Chinese chemical group: which document answers which question — due diligence on the entity, not the logo wall.
- Document consistency across a multi-entity supply chain — the four names that must agree.
Sources
- PubChem — Carbon tetrafluoride, CAS 75-73-0: https://pubchem.ncbi.nlm.nih.gov/compound/6393
- PubChem — Hexafluoroethane, CAS 76-16-4 (CID 6431): https://pubchem.ncbi.nlm.nih.gov/compound/6431
- PubChem — Octafluorocyclobutane, CAS 115-25-3: https://pubchem.ncbi.nlm.nih.gov/compound/8263
- NIST WebBook — Hexafluoropropene, CAS 116-15-4 (lists UN 1858, R 1216): https://webbook.nist.gov/cgi/cbook.cgi?ID=116-15-4
- NOAA CAMEO Chemicals — Hexafluoropropylene, CAS 116-15-4, UN/NA 1858: https://cameochemicals.noaa.gov/chemical/843
- ASHRAE — Refrigerant designations (R-14, R-116, R-C318 and R-41/CH₃F are distinct entries): https://www.ashrae.org/technical-resources/standards-and-guidelines/ashrae-refrigerant-designations
- EIGA Doc 199 / AIGA 018 — Safe handling of electronic specialty gases (PDF): https://www.eiga.eu/uploads/documents/DOC199.pdf
- SEMI C3 — Specification for Gases (limits in mole/mole): https://store-us.semi.org/products/c00300-semi-c3-specification-for-gases
- SEMI — Opportunities in Electronic Specialty Gases (packages: small cylinders, tonner/Y packages, tube trailers): https://www.semi.org/en/blogs/technology-trends/opportunities-in-electronic-specialty-gases
- State Council of the PRC — Regulations on the Safety Administration of Dangerous Chemicals (Decree No. 591): https://www.gov.cn/zhengce/2011-03/11/content_2602576.htm
Prepared by Hangrui Holdings Limited (Hong Kong) — the group holding company. Shipments of electronic specialty gases are contracted, invoiced and shipped by the group’s operating companies: HARMONY TECHNOLOGY (ZHEJIANG) CO., LTD. (trading), QUZHOU HUAFU NEW REFRIGERATION MATERIAL CO., LTD. (storage and cylinder filling), and RIBOLUO CHEMICALS (ZHEJIANG) CO., LTD. (distribution). This page is group reference material — the holding company does not contract, invoice or ship. Purity, impurity and moisture limits are those stated in the supplier’s specification sheet and certificate of analysis for the batch shipped; designations, UN numbers and classes quoted here are published identifiers, and the classification of a given shipment is the one declared in that product’s SDS.
Need current specs, quota status, or a mixed-load quote for the CAS List and How They Are Specified? Contact tom@hangr.hk with your spec & destination port.