The country of origin of High-Purity Hydrofluoric Acid 49% (HF 49%)

N354291 October 21, 2025 OT:RR:NC:N3:136 CATEGORY: Origin Andrew Park Andrew J. Park, CHB 19515 S. Vermont Ave., Suite 100 Torrance, CA 90502 RE: The country of origin of High-Purity Hydrofluoric Acid 49% (HF 49%) Dear Mr. Park: In your letter dated September 27, 2025, on behalf of your client, ENF (Kyle) Technology, LLC, you requested a country of origin ruling on High-Purity Hydrofluoric Acid 49% (HF 49%). In your submission, you describe a scenario where raw material, Anhydrous Hydrogen Fluoride (AHF), is sourced from China and shipped to South Korea. The AHF undergoes a series of production steps in Korea, resulting in the finished product, High-Purity Hydrofluoric Acid 49% Solution (HF 49%). The processing in South Korea is described as follows: 1. Controlled dilution of AHF with ultrapure water (UPW). 2. Impurity removal processes achieving parts-per-trillion (ppt) purity levels. 3. Rigorous quality control to meet semiconductor and electronic-grade standards. The end product is a high-purity HF solution suitable for direct use in advanced industries (semiconductor wafer etching, displays, PV cells, fiber optics). You also provide the following information: • Distinct Name: • Raw input: Anhydrous Hydrogen Fluoride (AHF), a volatile precursor chemical. • Finished product: High-Purity Hydrofluoric Acid 49% (HF 49%), an electronic-grade solution. • Distinct Character: • AHF: Toxic, corrosive feedstock with ppm-level impurity standards. • HF 49%: Purified, stable solution with ppt-level impurity controls. Character fundamentally altered for semiconductor applications. • Distinct Use: • AHF: Intermediate feedstock for fluoropolymers, refrigerants, and rubbers. • HF 49%: Directly consumed as a finished product in wafer etching, display panels, photovoltaics, and fiber optics. You claim that the Korean processing is not mere dilution. It involves highly controlled dilution, purification, and advanced manufacturing. • CAS Number: • Both AHF and HF 50% fall under CAS No. 7664-39-3. • Differentiated in SDS as “Anhydrous Hydrogen Fluoride” vs. “Hydrofluoric Acid (50% aqueous solution)”. • Purity: • AHF: ppm-grade (10). • HF 50%: refined to ppt-grade (10¹²). • Commercial & Functional Differences: AHF (Anhydrous HF) • Role: Industrial raw material; precursor for fluorine-based chemicals. • Properties: Highly volatile (b.p. 19.5°C); extremely hazardous; handled as both gas and liquid. • Use: Consumed mainly by large chemical/materials manufacturers. Not directly used in semiconductors due to impurity and handling issues. • Trade Practice: Rarely transported long distances due to hazards; mostly processed locally. HF 49–50% (Hydrofluoric Acid Solution) • Role: Final, marketable product. • Properties: Stabilized aqueous solution, easier to handle/store. • Use: Directly consumed by end users across industries: • Semiconductor wafer cleaning & oxide etching (ppt–ppb grade). • Solar wafer cleaning. • Metal surface treatment (stainless steel, titanium, nickel alloys). • Glass and optical etching. • Trade Practice: Sold as the commercial standard form of HF to end-use customers (electronics, solar, chemical processing sectors). Key Determinations Relevant to CBP: • AHF cannot be used directly in semiconductor or precision industries without conversion into aqueous HF due to purity and form issues. • HF 50% is a distinct commercial product, recognized in purchase orders and industry practice as separate from AHF. When determining the country of origin, the substantial transformation analysis is applicable. See, e.g., Headquarters Ruling Letter (“HQ”) H301619, dated November 6, 2018. The test for determining whether a substantial transformation will occur is whether an article emerges from a process with a new name, character, or use different from that possessed by the article prior to processing. See Texas Instruments Inc. v. United States, 681 F.2d 778 (C.C.P.A. 1982). This determination is based on the totality of the evidence. See National Hand Tool Corp. v. United States, 16 C.I.T. 308 (1992), aff’d, 989 F.2d 1201 (Fed. Cir. 1993). Regarding the country of origin of the High-Purity Hydrofluoric Acid 49% (HF 49%). It is our view that the Anhydrous Hydrogen Fluoride (AHF), sourced from China, imparts the finished product’s essential character . In South Korea, the dilution process, impurity removal process, and quality control process, do not result in a substantial transformation of the Anhydrous Hydrogen Fluoride (AHF) of Chinese origin. Therefore, it is the opinion of this office that the country of origin of the High-Purity Hydrofluoric Acid 49% (HF 49%) is China. The holding set forth above applies only to the specific factual situation and merchandise description as identified in the ruling request. This position is clearly set forth in Title 19, Code of Federal Regulations (CFR), Section 177.9(b)(1). This section states that a ruling letter is issued on the assumption that all of the information furnished in the ruling letter, whether directly, by reference, or by implication, is accurate and complete in every material respect. In the event that the facts are modified in any way, or if the goods do not conform to these facts at time of importation, you should bring this to the attention of U.S. Customs and Border Protection (CBP) and submit a request for a new ruling in accordance with 19 CFR 177.2. Additionally, we note that the material facts described in the foregoing ruling may be subject to periodic verification by CBP. This ruling is being issued under the provisions of Part 177 of the Customs and Border Protection Regulations (19 C.F.R. 177). A copy of the ruling or the control number indicated above should be provided with the entry documents filed at the time this merchandise is imported. If you have any questions regarding the ruling, please contact National Import Specialist Nuccio Fera at nuccio.fera@cbp.dhs.gov. Sincerely, (for) Evan Conceicao Designated Official Performing the Duties of the Division Director National Commodity Specialist Division