Bra Cup Terminology Glossary for Buyers

When you source bra cups from a factory, the fastest way to avoid costly misunderstandings is to share one vocabulary. The same word can mean different things depending on who is speaking — “ILD,” “density,” “mold,” “sample,” “MOQ.” This glossary collects the terms buyers most often ask about, with the Chinese term in parentheses so you can match what your supplier says on a call or in a quote. Where a number applies to Senfeng’s PU foam cups, we give the real range rather than a vague adjective.

Foam and Material Terms

• Density (密度) — The mass of foam per unit volume, measured in kg/m³. For PU foam bra cups the practical range is 25–30 kg/m³. Too low and the cup collapses under load; too high and it turns stiff and heavy.
• ILD — Indentation Load Deflection (压陷硬度) — The force needed to compress foam by 25% of its thickness. It is the industry-standard number for firmness. Senfeng’s cups sit in the ILD 28–35 band.
• Rebound (回弹) — How quickly foam returns to shape after compression. PU foam rebounds fast and holds its arc; this is what keeps a cup from developing a permanent dent in wear.
• Open-cell vs closed-cell (开孔 / 闭孔) — Whether the foam’s internal pores connect. Most molded bra cups use open-cell foam so air escapes during molding and the finished cup breathes.
• Yellowing resistance (耐黄变) — A material’s ability to resist discoloration from UV, heat, or phenolic contact during storage. Senfeng cups are built to a 4-grade standard.
• PU foam (PU 海绵) — Polyurethane foam, Senfeng’s core material, thermoformed into one-piece cups. It is different from memory foam (记忆棉), which contours slowly; Senfeng makes PU foam cups and does not produce memory foam.

Molding and Manufacturing Terms

• Molded cup (模压杯) — A cup formed in one piece from foam inside a heated mold — seamless and consistent at volume.
• Thermoforming / hot-press (热压成型) — Shaping PU foam sheet under heat (160–200°C) and pressure (15–30 tons) with an 8–15 second dwell.
• Vent holes (透气孔) — Small holes (default 1.5–2 mm, 6–12 per cup at Senfeng) that let air escape in molding and improve breathability. Applied at no extra charge.
• Mold (模具) — The shaped tool that defines a cup’s geometry. Senfeng keeps 2,000+ existing molds.
• Sampling (打样) — Producing a first cup to a spec. From an existing mold this takes 1–2 days; a new mold takes 3–7 days.
• Confirmed sample / sealed sample (封样) — The approved reference cup kept by both sides; bulk production is measured against it.

Quality and Compliance Terms

• OEKO-TEX Standard 100 — Certifies the finished article limits harmful substances; it is issued by product class, not by a single universal label.
• GRS — Global Recycled Standard (全球回收标准) — Certifies recycled content in the material; eligibility depends on the foam lot used.
• ISO 9001 (质量管理体系) — Certifies the factory’s quality management system, not a specific foam test result.
• Yield / pass rate (合格率) — The share of cups that pass inspection. Senfeng holds 95%+ across production.
• Traceability (可追溯) — Recording each batch’s mold number, foam lot, shift, and hot-press parameters so any cup can be traced back.
• AQL (验收质量限) — Acceptable Quality Limit, a sampled inspection standard (for example ISO 2859-1 / ANSI-ASQ Z1.4) used to decide lot acceptance.

Commercial and Shipping Terms

• MOQ — Minimum Order Quantity (最小起订量) — The smallest production run a factory will accept. Senfeng’s bra cup MOQ is 500 pairs. For what that number really means in practice, see our explainer on MOQ and lead time.
• Lead time (交期) — The time from spec lock to finished goods. It excludes courier transit and buyer review rounds.
• Capacity lock (锁产能) — Reserving production slots ahead of peak season — at Senfeng, up to 60 days before.
• Sinosure (中信保) — China Export & Credit Insurance; Senfeng’s export receivables are covered, supporting 8 years of exporting with zero bad debt.
• HS code (海关编码) — The harmonized tariff code used for customs declaration; the exact code depends on the destination authority. Our guide to HS codes and customs for bra cup export covers the paperwork side.

These terms sit on top of a real production base: a Dongguan factory making PU foam molded cups since 2006, with OEKO-TEX Standard 100, GRS, and ISO 9001 in place, per-shift parameter records on every batch, and full traceability. Browse the full bra cup range or read about Senfeng to see how the vocabulary maps to our actual capability.

Frequently Asked Questions

Why does density matter more than “soft” or “firm”?

Because adjectives vary by speaker. Density in kg/m³ is measurable and comparable across suppliers. Senfeng states 25–30 kg/m³ so you can verify it against a sealed sample rather than trusting a word.

Is ILD the same as hardness?

ILD is one measured way to express firmness — the force to compress foam 25%. Other test methods exist, so always ask which standard was used and compare against your sealed sample, not against a supplier’s label.

What does a “confirmed sample” protect me from?

It is the binding reference. Bulk production must match it on density, ILD, vents, and shape, and those values are recorded with per-shift hot-press parameters. If a lot drifts, the sealed sample is what both sides measure against.

Do these certifications test yellowing or chlorine resistance?

No. OEKO-TEX, GRS, and ISO 9001 each cover a different dimension — harmful substances, recycled content, and management system — and none replaces buyer-sent third-party testing for yellowing or chlorine resistance.

What is the smallest order Senfeng accepts?

500 pairs per run, counted by color or by run. For peak season, reserve capacity 60 days ahead so your slot is held when demand is highest.

Contact us directly: WhatsApp +86 137 1289 0858 | Website: sf-bracup.com