Quick answer. The first question on this construction is which waistband you are buying: an elastic band, a turned and bonded self-fabric band, or a raw sealed cut. Most bonded panties use the second, and only the third is genuinely elastic-free. Everything else in the specification — negative ease, gusset, edge tolerance, grading — follows from that choice, which is why a quotation that omits it describes nothing.
1. Three waistband constructions, and only one of them is “no elastic”
Buyers often arrive with the brief “no elastic at the waist” and a reference photo. There are three ways to build that waist, and they behave differently enough that the quotation is meaningless until one is chosen.
- Elastic band. Woven or knitted elastic, either encased in a turned channel or bonded on. Hold comes from the elastic; the fabric only has to follow. It is the most forgiving option, and the one that conventional thong and brief construction assumes.
- Bonded self-fabric band. The body fabric is turned and bonded down, usually over a 12 to 20 mm band, with no elastic inside. Hold comes from the stretch in the knit and the negative ease built into the pattern. This is what most laser-cut bonded panties actually are.
- Raw laser-cut edge at the waist. No band at all. The waist is simply a sealed cut. It gives the flattest line and the least hold, and it is the version that comes back as a complaint when the fabric has been chosen for hand rather than for recovery.
Only the third has no elastic anywhere in the waist structure. The second still contains elastane — in the fabric. That distinction matters later, when the claim goes on the pack.
2. What the pattern has to do when the elastic goes
An elastic band is a spring that pulls the garment onto the body and keeps pulling. Remove it and the same job falls to two things: how much the knit can stretch, and how much smaller than the body the pattern is cut.
- Negative ease moves into the fabric. The pattern has to be reduced enough that the knit is under tension at the waist and the leg, and the reduction has to be set per fabric — a 90/10 nylon/elastane and an 85/15 do not want the same number.
- Composition is not enough as a specification. Two knits at 90/10 can differ in how much they extend at a given load and how much they grow after repeated extension. Ask for both figures, at a stated load, rather than accepting the blend ratio as a proxy.
- Recovery is the number that fails. A fabric that stretches well and recovers badly gives a panty that feels right in the sample room and loose at the waist after a month of wear — which is a return, not a reorder.
- The bond does not stretch like the fabric. A bonded band is stiffer than the panel around it. The pattern has to place that stiffness where the body tolerates it, which is why the band depth and the bond width are pattern decisions, not finishing decisions.
3. The edge is the finish: two tolerances, not one
With no binding, the cut edge is the visible finish, so the tolerance on the cut becomes a customer-facing tolerance. There are two distinct specifications here and they are routinely quoted as one.
- Clean cut on a jersey. The laser seals the edge as it cuts. The requirement is a straight, flat line with no scorch, no glazing and no measurable curl. Rib knits tend to curl at a cut edge whatever the cutting method, which is why rib is a poor choice for an exposed bonded edge.
- Scalloped cut on a lace. The scallop follows the motif, so its depth and repeat come from the lace, not from the laser. Two mills cutting the same lace can still deliver different scallops if one laser-cuts and one ultrasonically cuts, because the two methods seal the motif differently.
- What to put on the drawing. The cut method, the scallop repeat measured in millimetres, and the position of the scallop relative to the leg curve. “Scalloped edge” alone is not a specification.
4. The gusset becomes the only seam
In a bonded panty almost everything is joined flat, which leaves the gusset lining as the one place where two pieces are usually still sewn — or the one place where a bond has to survive the most abrasion and the most washing.
- Decide which it is. A sewn gusset and a bonded gusset are different specifications with different failure modes, and a sample that quietly uses one when the brief said the other is a substitution, not a detail.
- If sewn, specify the seam. Stitch type, seam allowance and thread matter more here than anywhere else on the garment, because it is the only seam the wearer can feel.
- If bonded, specify the tape. Width, chemistry and activation, plus the peel figure on the finished garment after the care cycle — the same discipline that applies to the leg opening.
- Put the gusset on its own specification line. Fibre, weight and colour, separately from the body — the panty manufacturing guide covers that format. What changes on a bonded style is only that the gusset is the one seam left, so it is one of the components most often swapped without telling the buyer.
5. Thong and G-string: bond width is the design
On a brief there is room to hide a bond line. On a thong there is not: the string is a narrow strip, and the bond runs along both of its edges for the whole length.
- Bond width against strip width. If the bond takes most of the strip, the string goes stiff — which defeats the point of the style. If it takes too little, the string rolls.
- Two edges, one strip. Both edges have to be sealed, so the tape allowance is doubled relative to a brief, and the marker has to plan for it.
- The waist join is the stress point. The point where the string meets the waistband carries the load of the whole garment and is usually the first place a bonded thong fails. It is worth its own trial rather than being assumed from the brief.
6. Grading: the ends of the run need their own bond spec
A bond that holds at M does not automatically hold at XXS or at 4XL, and the reason is geometric.
- Small sizes. The bond line is short and sits close to a tight curve, so the same tape occupies a larger share of the panel and stiffens it. Curves that are gentle at M become tight at XXS.
- Large sizes. The bond carries more load at the same width. Bond width, or the peel requirement, usually has to step up at the top of the run.
- What to ask for. A peel figure at the smallest and the largest size, not only at the middle. If a supplier quotes one number for the whole run, that number describes one size.
- Related reading. The verification points for plus-size seamless programmes apply here too, because the failure at the top of the run looks the same whichever way the seam was removed.
7. The claim: “no elastic” is a construction statement, “elastic-free” is a fibre claim
This is the part that gets brands into trouble after the product is live, and it costs nothing to get right at the brief stage.
- What is true. The waist has no elastic band. That is a construction statement about the garment.
- What is also true. The fabric is normally nylon/elastane or polyester/elastane, so the garment contains elastane. An unqualified “elastic-free” or “no elastic” claim on a pack or a listing can be read as a fibre claim about the whole product.
- How to word it. Describe the construction — “no elastic band at the waist” or “bonded self-fabric waistband” — rather than the fibre. Care and fibre content on the label follow the textile labelling rules of the destination market; in the US that is the FTC’s clothing and textiles guidance; in the EU, fibre labelling under Regulation (EU) No 1007/2011 and the general product-safety duties under Regulation (EU) 2023/988.
- Keep the claim and the test report in the same file. If the claim is about washing or hold, it needs a test behind it. A claim that no one can check is a claim that can be challenged.
8. What to test before you print anything
- The bond. T-peel to ISO 11339:2022 on specimens cut from the bonded seam at the leg opening and at the waist join, after the care cycle. The standard describes a prepared flexible-to-flexible assembly, so specimen preparation is agreed with the laboratory.
- The care cycle. Wash to the condition you intend to print, under ISO 6330:2021, to the wash count in the claim rather than to one cycle.
- Colour. Fastness after the same cycle to ISO 105-C06, because a bonded panty that changes shade after five washes has still broken a promise.
- The label. Care symbols to ISO 3758:2023, agreed against the tape rather than against the fibre — the tape is what limits the temperature.
- The batch. Sampling to ISO 2859-1, with the bond checked as a separate defect class from the sewing defects. A bonded garment has fewer stitches to inspect and more surface to inspect; the inspection plan should reflect that.
- The certification. OEKO-TEX Standard 100 Class II is the class for articles with large areas in direct contact with the skin, which is where a panty sits. Ask for the certificate and check the number at the issuing body rather than accepting a logo on a PDF.
9. Where this construction is the wrong answer
- High-support shaping. If the garment has to compress, an elastic band or a circular-knit programme does the job with less risk.
- Cotton-first briefs. Cotton-rich knits do not seal and do not bond, so the construction does not apply at all.
- Very light fabrics at the waist. A very light knit with little recovery will not hold a raw cut waist, and no amount of tape changes that.
- Programmes that need a strong waist print or a woven label at the centre front. A bonded waist leaves no seam allowance to hide either.
10. How we quote a bonded women’s programme
Unitex is a sourcing and trading company incorporated in Xiamen in 2013, working with partner factories that hold amfori BSCI and OEKO-TEX Standard 100 and that manufacture and bond the garments on their own lines. We are not the knitting or bonding line and we do not describe ourselves as a factory. What we do is match the brief to the partner line that should run it, and write the specification so the answer is checkable.
For a bonded women’s programme we ask four things before quoting: the waistband construction, the fabric with its stretch and recovery figures, the gusset decision, and the size range. Those four fix the pattern, and the pattern is the cost. A conventional panty specification can be quoted from a photo; a bonded one cannot, because the photo does not show which of the three waistbands it is.
If you are moving an existing style from an elastic waist to a bonded one, keep the pattern revision and the fabric lot together in the trial. Changing both at once means a failure cannot be attributed, and the fix becomes a guess. And if a competing quotation for the same style is materially cheaper, the first question is which waistband it is actually building — the second is which fabric.
How do you tell a reliable supplier from a merely compliant one on this construction? Ask what happens to the waist after 30 washes, at the largest size in the run. A supplier who answers with a figure and a method is describing a programme; a supplier who answers with a feeling is describing a sample.
· Xiamen Unitex Trade Co., Ltd. — OEM & ODM underwear sourcing partner