Bag fabric Specification: What Each Number Actually Changes

Two suppliers can quote the same bag fabric at the same headline figure and deliver different products. The difference is in the numbers nobody puts in the quotation, and in the tolerance behind the number that is quoted.

Why the headline number is the least useful one

Every quotation leads with base construction. It is easy to compare and it is the number the factory can hit most cheaply. But it tells you almost nothing on its own: base construction sets the frame, and the parameters below set whether the product survives its first year in service. A buyer who compares only the headline figure is buying a sample, not a supply agreement.

For bag fabric, the practical rule is to fix the headline figure at the level your product needs and then spend your negotiating attention on abrasion and tear strength. Those two are where cheap goods differ from adequate goods, and they are usually absent from the quotation sheet.

The numbers that decide performance

Read the table as a set of trade-offs rather than a checklist. Moving any single line usually costs money somewhere else, and the cheapest way to hit one figure is often to let another slip.

Base construction

Typical range: 600D / 840D / 1680D ballistic. Ballistic weave resists abrasion far better at the same weight.

Coating

Typical range: PU 1-3 coats, 20-80 gsm total. Coating weight is the real water and abrasion story, not the base denier.

Abrasion

Typical range: >= 25 000 Martindale. Trolley bags and backpacks live or die here.

Tear strength

Typical range: >= 40 N (1680D). The failure mode at over-packed seams.

Water repellency

Typical range: AATCC 22 >= 80. DWR, not waterproofing. C0 chemistry for EU buyers.

How to write a bag fabric specification that protects you

A specification is only useful if a substitution becomes visible. That means writing the construction and the performance together, and naming the test that proves each one. For bag fabric, the clause has to pin abrasion and tear strength, because those two separate a compliant lot from an adequate one:

1680D ballistic polyester, 2-pass PU with primer, 45 gsm coating, 1500 mm hydrostatic head, 25 000 Martindale, C0 DWR, wet rub >= grade 3, Pantone 19-4005 TCX

Note what is missing from that line: adjectives. No ‘high quality’, no ‘premium’, no ‘export grade’. Every clause is either a number with a tolerance or a named test. If a supplier cannot quote against a line written this way, that is information about the supplier.

Where the specification usually breaks down

The first failure is crocking on dark shades. Black bag straps mark a white shirt. The cause is usually surface pigment without a fixing topcoat. The test that exposes it before you order: ISO 105-X12 dry and wet, plus a 24 h contact test under 5 kg load.

The second is coating crack at folds. White lines at the gusset fold after a few months of use. It comes from too heavy a single coating pass, or a coating with low elongation. Test with Flex test 5000 cycles at the fold, then inspect and re-test hydrostatic head. and write the result into the purchase order, not just the enquiry.

Both failures share a pattern: they appear months after delivery, they are hard to attribute, and the cost lands on the buyer rather than the mill. That is exactly why the test belongs in the specification and the report belongs in the shipment file.

What to put in a bag fabric enquiry

1. End use and the conditions, which together decide where abrasion has to sit inside >= 25 000 Martindale.
2. The one figure that must hold, with abrasion named as the proof.
3. Quantity per colour and per delivery, against a typical MOQ of 800-1500 m per colour.
4. Destination market, because compliance changes the construction, not just the paperwork.
5. A physical standard viewed under a stated light source, not a screen proof.

With those five points we can quote against a real requirement instead of a generic range. Full ranges sit on the bag fabric page, and the manufacturing side of the same question is on our quality control page.

Questions buyers ask before ordering

Is 1680D always better than 600D?

For abrasion, yes, if the weave is genuinely ballistic and the coating is adequate. For a promotional tote, 600D is the right answer and 1680D is wasted money.

Do you offer C0 DWR?

Yes. We moved most programmes to C0 because EU buyers ask for it, and we will say plainly that performance after 10 washes is slightly below C6.

Can you supply GRS-certified recycled fabric?

Yes, with transaction certificates. Allow 3-4 weeks extra for the paperwork, and expect a 5-12 % price premium.

Failure modes worth a clause in the purchase order

Claims rarely come from a batch that was obviously wrong. They come from a abrasion figure that sat inside the quoted band and outside what the product needed.

The other two, with acceptance numbers attached, are in the full failure analysis for bag fabric. A supplier who cannot name the mode he sees most often is describing a catalogue, not a process.

Seven lines that turn a quotation into a specification

Most post-delivery arguments are not about quality. They are about a document that never said which figure would be measured, on which instrument, at whose cost.

1. Tear strength (>= 40 N (1680D)): name the number, not the word. If the answer only repeats the band, ask which point inside it is being offered for this order.
2. Water repellency: AATCC 22 >= 80 is the market band. Fix the figure you will test at goods-in, and the instrument you will test it with.
3. Colour fastness to rubbing (>= grade 4 dry, >= 3 wet): fix the value per shipment, and state who pays for the re-test if a lot lands outside it.
4. Weight: 200-500 gsm is not an answer on its own. Ask for the last three lots’ actual readings and the spread behind them.
5. Price validity: the period during which the quoted figure holds, and what happens to it when the raw-material index moves.
6. Remedy: rework, replacement or credit, and the point at which each applies.
7. Sample retention: one production sample per lot stays with the mill for twelve months. Claims are settled against it, not against memory.

Related reading

• Bag Fabric vs 600D polyester
• Water repellency in Bag fabric
• Bags and luggage