Your Logo on a Waterproof Bag: Which Methods Survive the Water

Whether a logo can be added is one of the first three questions almost every buyer asks us, together with the minimum order quantity and the price. The short answer is always yes. The more useful answer is that a waterproof bag is a harder surface to brand than a cotton tote or a polyester backpack, and the method that looks best on a sample card is not always the one that still looks right after a season of rain, salt water, sun and being rolled shut a few thousand times.

This guide explains how logos fail on waterproof bags, which application methods hold up on TPU and PVC, where on the bag a logo should and should not go, and what we check before a branded order leaves our factories in Dongguan and Ho Chi Minh City. It is written for brand owners, promotional buyers and product managers who want their logo to last as long as the bag does.

Three Ways a Logo Fails on a Waterproof Bag

The first failure is peeling or flaking, and it is almost always an adhesion problem. TPU and PVC are smooth, low-absorbency surfaces, so an ink or transfer cannot soak into the fibres the way it does on cotton. It has to bond chemically to the coating. An ink system designed for one coating can sit on top of another and look perfect on the day it is printed, then lift at the edges after a few weeks of use. Surface residues matter as well. PVC can carry plasticiser on its surface, and both materials can carry traces of release agents from the coating line, so the print area has to be clean before anything is applied.

The second failure is cracking at fold lines. A roll-top bag is folded tightly at the top every time it is closed, and a bike or kayak bag flexes constantly while in use. A thick, rigid ink layer or a stiff transfer placed in a flexing zone will eventually crack along the fold, and the cracks get worse in cold weather when coatings become less supple. The solution is partly in the ink, which should be thin and flexible, and partly in placement, which we come back to below.

The third failure is the most serious because it damages the bag rather than the logo. Any method that pushes a needle or a rivet through the waterproof shell creates a hole. A sewn patch or an embroidered logo on the body of a dry bag will let water in at every stitch, which defeats the purpose of high-frequency welded seams. This does not mean sewing has no place on a waterproof bag; it means sewn branding belongs on the parts that sit outside the waterproof envelope.

The Main Logo Methods, and Where Each One Fits

Screen printing

Screen printing is the most widely used method on waterproof bags and usually the most economical. Ink is pushed through a fine mesh screen onto the material, one screen per colour, so a one- or two-colour logo is simple and cost-effective, while a six-colour design takes more setup. On TPU and PVC the critical decision is the ink system, which must be matched to the coating, and the print is usually applied to flat panels before the bag is welded, which gives a sharper, more even result than printing a finished bag. Done properly, a screen-printed logo survives water, sun and normal abrasion for the life of the bag.

Heat transfer

Heat transfer prints the design onto a carrier film first and then presses it onto the bag with heat and pressure. It handles fine detail, small text, gradients and full-colour artwork better than screen printing, which makes it a good choice for complex brand marks or photographic designs. The adhesive layer must suit the coating, and because a transfer is a separate layer it is best kept away from the tightest folds, where its edges could start to lift.

High-frequency embossing and debossing

Because we already weld bags with high-frequency equipment, we can press a logo directly into the material with a custom brass die. The logo becomes part of the surface, raised or recessed, with no ink to wear away. The result is a tone-on-tone, understated look that many outdoor brands prefer, and it is one of the most durable options available. The trade-off is a one-time die cost and a design that works best as a bold shape rather than fine lines or small text.

Welded patches

A welded patch is a separate piece of TPU or PVC, often printed or embossed with the logo, that is welded onto the bag rather than sewn. It gives a raised, finished look and keeps the shell intact because no needle passes through it. Welded patches are especially effective on dry bags, duffels and motorcycle luggage, and they can be cut to almost any outline.

Reflective logos

For bike bags, motorcycle bags and commuter backpacks, the logo can double as a safety feature. Reflective film can be cut to the logo shape and welded or heat-applied to the bag, so it shows the brand by day and reflects headlights at night. Like other transfers, reflective film should be specified for outdoor exposure and placed away from heavy flexing.

Embroidery, woven labels and sewn patches

Our sewing lines are as experienced as our welding lines, and embroidery and woven labels give a textile quality that printing cannot match. On a waterproof bag they belong on shoulder straps, hip belts, back panels, webbing, outer mesh pockets and any part that is not meant to keep water out. Planned this way, a bag can carry an embroidered badge on the shoulder strap and a printed or welded logo on the waterproof body, and neither compromises the other.

Branded hardware and trims

Some of the most effective branding is not on the fabric at all. Custom zipper pulls, moulded buckles with a debossed logo, metal badges and laser-engraved D-rings carry the brand on the parts customers touch every time they use the bag. Hardware branding usually needs its own mould or die, and any metal part should be specified to resist salt water and road salt.

How the Methods Compare

Placement Is Half the Decision

Even the right method fails in the wrong place. On a roll-top bag, the top section that is rolled to close the bag flexes every single time it is used, so a printed logo there will crack long before one on the flat body. We place logos below the roll zone, usually in the centre of the body where the surface stays flat when the bag is packed.

Seams are the second consideration. A high-frequency weld needs two clean surfaces to fuse, and ink or transfer film in the seam allowance can weaken it, so artwork is kept clear of every weld line. Abrasion zones are the third. The base of a dry bag, the back of a motorcycle saddlebag and the side of a handlebar bag that rubs against cables all wear faster than the rest of the bag, and a printed logo placed there will fade early. On those positions, an embossed or welded logo is the better choice.

Finally, the logo has to be readable when the bag is in use. A logo centred on a dry bag looks good when the bag is full and upright, but on a backpack it may be hidden by compression straps, and on a motorcycle bag it may face the bike rather than the road. We review placement on the actual bag shape during sampling, not only on a flat artwork file.

Colour Matching on Coloured Fabric

Brand colours are usually supplied as Pantone references, and we match ink to those references for every order. On dark or strongly coloured TPU and PVC, light ink colours often need a white underbase so they do not look dull or shifted by the fabric underneath, which adds a print step but keeps the brand colour true. Every bulk order is checked against the approved sample for colour difference under standard lighting, so the logo on the thousandth bag matches the one on the first.

Branded Products in Our Range

Each of the products below is available with your logo using one or more of the methods above. We recommend the method based on the bag's material, shape and use rather than applying one method to every product.

How We Check a Branded Order Before Shipment

A logo is checked as carefully as the bag it sits on. Inks, transfer films and patch materials are inspected at IQC when they arrive, printing and welding are monitored at IPQC on the production line, and finished bags are checked at OQC before packing. SGS or QIMA third-party inspection is available on request.

For the logo itself, production samples go through adhesion testing, where tape is pressed onto the print and pulled away to confirm nothing lifts, together with abrasion testing and colour fastness testing, including wet rubbing, so the print does not wear through or transfer onto clothing. Colour difference is checked against the approved sample. Metal badges and branded hardware go through salt spray testing. The rest of the standard suite still applies to every branded bag: tensile and bonding strength, a load test of 1,500+ cycles and zipper fatigue testing to 3,000 cycles.

Because the logo must never compromise the bag, finished branded bags are also verified against their waterproof rating, with a heavy rain and water-jet test for IPX5 and IPX6 products and a full water-immersion test of 2+ hours for IPX7 products. For air-tight and compression products, buyers can follow our standard customer inspection procedure on arrival: unboxing, vacuum extraction, a 24-hour static rest and air-leak determination.

Frequently Asked Questions

What is the MOQ for bags with our logo?

Most of our waterproof bags start at 300 pieces with your logo, and some styles start at 500 pieces. Adding a logo does not usually change the MOQ of the bag itself. A custom fabric colour or newly developed hardware can raise it because those materials have their own minimums.

How much does adding a logo add to the price?

It depends on the method, the number of colours and the number of positions. Screen printing a one-colour logo in one position adds the least. Each extra colour, extra position or full-colour transfer adds to the unit cost, and embossing dies, patch dies and hardware moulds are one-time charges. We include all of these in the quotation so you can compare options side by side.

Will the logo peel or crack?

Not when the method, ink system and placement are matched to the bag. Most peeling comes from ink that does not suit the coating, and most cracking comes from printing in a fold zone. We specify both during development and confirm adhesion and abrasion resistance on production samples before bulk printing.

Can you embroider our logo on a dry bag?

We do not embroider through the waterproof body of a dry bag, because every stitch would create a hole. We can embroider on straps, webbing and other parts outside the waterproof area, or use a welded patch or high-frequency emboss on the body for a similar finished look.

Can we see a sample with our logo before bulk production?

Yes. Branded samples are usually ready in 7–15 days after artwork approval, and bulk production typically follows in 30–45 days. Please send your logo as a vector file, such as AI, EPS or PDF, with Pantone references.

Can you put a logo on the zipper pulls and buckles too?

Yes. Custom zipper pulls, debossed buckles and laser-engraved metal parts are available and are often the most noticed branding on a bag. They need their own mould or die, so we recommend them for programmes where the order volume justifies the setup.

Brand Your Waterproof Bag Range With Us

We have been making and branding waterproof bags for over 20 years, for outdoor, marine and lifestyle brands including West Marine, Helly Hansen and Disney. Send us your logo, your target products and how the bags will be used, and we will recommend the method and placement for each one and prepare branded samples. Contact us at info@sealock.com.hk or call +86-769-82009361.