Start the RFQ with the seat, not the blanket
For stadium seat programs, the backing requirement is different from a lawn picnic rug. The blanket must grip smooth polypropylene, HDPE, painted steel or powder-coated aluminium seats while still folding small enough for turnstile entry, giveaway bins or retail belly-band packing. A practical base spec is 200gsm knitted polyester polar fleece, often 150D/144F or similar microdenier yarn, brushed on the face and sheared to a stable pile. Common finished sizes are 120 x 150cm, 130 x 150cm and 130 x 170cm. Larger sizes increase seat drag, folding bulk and visible edge distortion after washing.
Separate fabric mass from coating mass. Write the base as “200gsm +/-5% polar fleece before dot coating” and the finished article as “approximately 220-245gsm depending on approved EVA dry add-on”. If the buyer only writes “200gsm anti-slip fleece”, suppliers may quote 170-180gsm fleece plus dots to hit the total weight. That saves material but gives a thinner hand, weaker overlocked edges and more curl after domestic washing.
EVA dots are a grip aid, not a waterproof backing. EVA hot-melt dots or EVA-based compounds are lighter and less rubbery than many PVC dot systems, and usually cheaper than silicone dots, but they do not create hydrostatic resistance. If the program needs damp-ground protection, specify PEVA, PU, TPU or Oxford backing instead; see picnic blanket backing PEVA, PU and TPU options. For this product, the PO should state “seat-grip use, not waterproof ground-mat use”.
A complete RFQ line should include: base fleece GSM and tolerance, finished size and tolerance, EVA system and dot colour, dry add-on, dot diameter and pitch, edge finish, logo method, care label, wash cycles, seat-grip test, AQL level, packing method, carton stacking limit, Incoterms and retained sealed sample requirements. Decoration should be quoted separately because embroidery, heat transfer and screen print can change stiffness, dot blocking and folding behaviour.
Clarify the EVA system before sampling
Do not use “EVA backing” as a single technical term. There are three common meanings in sourcing conversations, and they do not fail in the same way. EVA hot-melt dots are thermoplastic dots applied warm and set by cooling; risks are heat softening, blocking in hot cartons and pressure flattening. EVA-based plastisol or compound dots use EVA or EVA-compatible resin with fillers, pigments and processing aids; risks are odour, poor cure, additive migration and dot loss if viscosity is wrong. Thermal bonding or curing refers to the heat stage used to anchor the dots to the fleece; it is a process condition, not a material description.
For 200gsm polar fleece stadium blankets, a realistic dry add-on is often 18-45gsm. Around 18-25gsm gives a soft fold, lower cost and better carton yield. Around 28-35gsm is a common medium grip range for smooth plastic seats. Above about 38-45gsm, the reverse may feel boardy, block in warm cartons, flatten at fold lines, or leave raised pressure marks on the face after tight packing.
These ranges are not arbitrary. Many dot-coating lines used for fleece blankets work with engraved rollers, rotary screens or patterned transfer systems that have practical limits for dot height, paste release and pattern cleaning. Very small dots below about 2.0-2.5mm can under-fill or disappear into brushed nap. Large dots above about 4.5-5.0mm can spread, bridge between cells, or crack on folds. Pitch tighter than about 7-8mm raises add-on quickly and makes cleaning more difficult; pitch wider than about 14-18mm often leaves too few contact points on curved seats.
More coating does not always improve grip. Heavy dots can spread into islands, crack where the blanket is folded, or sit on loose fibre tips instead of anchoring into the knit ground. High-pile fleece is sensitive: the dot may look tall and clean on the sample table but shed after washing because it bonded to loose nap rather than the base fabric. The manufacturing target is controlled penetration into the fleece back without strike-through to the face.
Use measurable PO language: “EVA dot coating dry add-on 28-35gsm, measured by before/after panel weight from the same roll and same size area; production tolerance +/-5gsm against approved bulk standard.” The factory should retain uncoated reference fabric from the same dye lot. Without that reference, disputes over coating weight become difficult because fleece GSM can vary across the roll.
Choose EVA, silicone or PVC with the right risk view
EVA dots are usually selected for promotional and mid-market stadium blankets because they are light, flexible, economical and can be applied in a clean dotted pattern. Their weak points are heat ageing, blocking under compression, odour if poorly compounded, and dot loss if viscosity, curing or fleece preparation is not controlled.
Silicone dots generally outperform EVA for heat ageing, wash durability and long-term elasticity, especially where the blanket may be repeatedly laundered or stored in hot containers. The trade-off is higher material cost, slower curing or more demanding process control, and sometimes higher MOQ. For a related anti-slip construction, see silicone anti-slip dot backing.
PVC dots can give strong initial grip and high build, but they raise plasticiser, phthalate, odour and regulatory questions for some markets; they also tend to feel heavier on a soft fleece throw. If PVC or PVC-alternative language appears in the buyer’s brief, require a chemical compliance review before PP approval, not after bulk production.
EVA becomes a weak choice when the route includes high-temperature container storage, long dwell under carton compression, repeated laundering, damp-ground performance claims, heavy heat-transfer logos, high-pile fleece, or steep glossy stadium seats. Those programs should trigger silicone validation, a different anti-slip compound, or a real picnic-mat backing. If the buyer needs waterproof performance, move to a backed picnic-mat construction rather than increasing EVA dot weight; compare waterproof picnic mat backing options.
Decision table by use case
The right EVA specification depends on how the blanket is sold or distributed. The table gives a practical starting point for sampling; final approval should be based on the buyer’s actual seat material, packing route and wash claim.
| Use case | Suggested base | EVA dry add-on | Dot diameter / pitch | MOQ and cost impact | Risk level |
|---|---|---|---|---|---|
| Stadium giveaway | 200gsm polar fleece, 120 x 150cm or 130 x 150cm, overlocked | 18-28gsm | 2.5-3.5mm / 10-14mm | Lowest add-on cost; better carton yield; efficient for high-volume tenders | Medium: slide claims if seats are glossy, dusty or steeply angled |
| Retail fan blanket | 200-220gsm fleece, 130 x 150cm or 130 x 170cm, overlock or stitched trim | 28-35gsm | 3.0-4.0mm / 8-12mm | Moderate material increase; packing must protect dot face | Medium: chargebacks for dot shedding, odour or carton blocking |
| Premium merch or season-ticket pack | 220-250gsm fleece or microfleece, tighter shear, branded trim | 32-45gsm EVA, or silicone for higher wash expectation | 3.0-4.5mm / 7-10mm | Highest cost; smaller MOQ limited by coating setup and packaging | High: compression, heat-transfer logos and repeated washing must be validated |
MOQ is driven by the fleece dye lot, the dot screen or roller, compound colour, decoration and packing format. For Tongxiang-style fleece production, custom dyed fleece often becomes the largest MOQ driver, while a standard navy, charcoal or grey fleece with white EVA dots can be easier to place. A custom dot colour may require separate compound mixing, screen cleaning and waste allowance even when the fleece is stock.
Use a simple cost-impact calculation before approving a heavier dot: extra dry add-on in gsm x finished blanket area in square metres x order quantity = added dry coating kilograms before loss. A 130 x 150cm blanket is 1.95m². Moving from 25gsm to 35gsm adds about 19.5g per blanket, or about 195kg per 10,000 pieces before coating loss, packing-weight impact and freight cube effects. That extra material may be justified for retail grip, but it is often wasted on a one-event giveaway.
Approve dot geometry with a reproducible seat-grip test
Dot spacing controls grip, weight, handfeel and shedding risk. For 200gsm fleece stadium blankets, start sampling with dots about 2.5-4.0mm diameter on an 8-12mm centre-to-centre pitch. A dense 6-8mm pitch feels grippy by hand but adds weight and can make the blanket drag when users reposition it. A wide 14-18mm pitch saves coating, but the blanket may slide on curved plastic seats because too few dots contact at one time.
Ask for at least two strike-offs: one light grid and one medium grid. Test on actual seat material when possible, not only on clean glass or stainless steel. Stadium seats may be textured, UV-aged, waxed by cleaning chemicals, dusty or slightly curved. A dot pattern that grips a flat lab board may slide on a curved seat pan.
FIELDLOOM uses a buyer-agreed internal method we call FG-01 Incline Seat-Grip Test when no retailer method is supplied. It is not an ISO claim; it is a reproducible comparison protocol for approving the golden sample and checking bulk. Condition samples for 4 hours minimum at 20 +/-2°C and 65 +/-5% RH. Use a 300 x 300mm swatch with dotted side down on a 300 x 300mm seat substrate fixed to an adjustable incline plane.
FG-01 standard substrate options are buyer-supplied stadium seat material, injection-moulded polypropylene panel, HDPE panel, powder-coated steel plate or painted aluminium plate. Clean the substrate with neutral detergent and water, rinse, dry fully and record the surface. Place a 5.0kg flat load over a 250 x 250mm contact area. Dwell for 10 minutes at 15°. Acceptance: no continuous slide greater than 20mm, no sudden slip, no dot transfer, no smear and no visible dot/fibre shedding after five lift-and-replace cycles.
Run two variants for realistic use. For the wet variant, wipe the substrate with a damp lint-free cloth and leave a visible but non-puddled film; repeat the 15° dwell and accept no slide greater than 30mm. For the dusty variant, apply 0.5g of standard fine household dust or agreed talc substitute evenly over the 300 x 300mm panel, then repeat; accept no slide greater than 40mm and no clumped dot contamination. For steep glossy seats, add a 20° challenge, but treat it as a development target unless written into the PO.
If the buyer wants a coefficient-of-friction comparison, use an ASTM D1894-style sled setup as an internal comparative method: same seat substrate, same sled mass, same contact area, same pull speed and same side of the blanket. Do not claim a universal COF value for all stadium seats. A practical internal target is that bulk retains at least 80% of the sealed sample slip-force value after the agreed wash test.
The PO should include dot drawings or scaled photos, not only numbers. State: “EVA round dot, non-continuous pattern, no connected streaks, no missing coating bands wider than 20mm, approved strike-off reference sealed by buyer and supplier.” Define defects clearly. Scattered missing dots may be minor; long uncoated lanes, smeared dots, burnt hard dots, tacky dots, or dots visible as glossy face marks should be major defects.
Set wash-adhesion criteria before bulk
For stadium giveaways, many end users will wash the blanket even if the item is mainly used on seats. The claim should not be vague. A practical baseline is ISO 6330 domestic washing, 40°C mild cycle, standard reference detergent or agreed non-bleach household detergent, no chlorine bleach, line dry at room temperature or low-tumble dry if the care label allows. Use the same drying method for approval and bulk checks.
A workable acceptance level for EVA-dotted 200gsm fleece is: after 3 wash/dry cycles, dot loss by count not more than 3% within a 300 x 300mm assessment area, no single bare area larger than 20 x 20mm, no tackiness, no grey dusting, no dot cracking visible at normal viewing distance, and visual rating at least grade 4 against the sealed unwashed control. For premium retail or repeated-use claims, test 5 cycles and consider silicone if the result is marginal.
Post-wash grip must also be checked. After washing and drying, repeat FG-01 on the same substrate used at approval. A reasonable production target is at least 80% slip-force retention compared with the approved unwashed sample in a sled comparison, or a pass on the 15° incline test with no slide greater than 25mm after 10 minutes. If the blanket passes visual dot retention but loses grip, the compound may have glazed, over-cured, under-cured or picked up detergent residue.
Do not approve only from a small hand-cut lab swatch. Wash one full blanket from the pre-production run, because edge curl, folding creases, logo cracking and dot-to-face transfer can appear only on the complete article. For care-label wording, align with ISO 3758 symbols where relevant and avoid over-promising wash durability. For general care-label discipline, see blanket care washing guide.
Compliance depends on market and claim
The compliance package should be set by destination market, age grading, material system and packaging. Do not assume EVA dots are automatically low risk because they are not PVC. Ask the compound supplier for formulation disclosure sufficient for testing, and freeze the approved compound code before PP approval.
For the EU and UK, common checks include REACH SVHC screening, restricted azo colourants for dyed or printed textile parts, formaldehyde where retailer limits apply, heavy metals in coatings and prints where relevant, fibre-content labelling, care labelling and packaging waste rules. If the blanket is marketed to children, add the buyer’s age-grade review and applicable toy or children’s textile requirements; do not place EN 71 language on adult stadium goods unless the sales channel requires it.
For the US, likely checks include CPSIA if the product is children’s merchandise, lead in accessible coatings where applicable, phthalates if PVC or soft plastic components are used, fibre-content labelling under FTC rules, care labelling, and CA Prop 65 review for California distribution. If the product includes a PVC pouch, rubber patch, metallic print or dark plastisol print, test that component separately; a compliant fleece body does not clear the whole SKU.
Odour and VOC screening are practical even when not mandated. EVA compounds with residual processing aids or contaminated fillers can smell acceptable on the coating line and become unacceptable after seven days in a sealed polybag. Add a sealed-bag odour check: 24 hours at 40°C, then assess immediately after opening by a trained internal panel or agreed retailer method. Reject strong solvent, sour, fishy or rubber-like odour.
For chemical and social compliance expectations across blanket programs, see textile certifications explained for buyers. Do not list certifications on the product page unless the specific factory, process scope and transaction documentation support the claim.
RFQ and PO wording buyers can use
A clean RFQ prevents the usual anti-slip disputes. Use wording like this: “200gsm +/-5% polyester polar fleece before coating; finished weight approx. 228-235gsm after approved EVA dot; size 130 x 150cm +/-3%; EVA white round dot, 3.0-4.0mm diameter, 8-12mm pitch, dry add-on 28-35gsm; no waterproof claim; seat-grip claim only; overlocked edges; care label to approved artwork; packed one piece per polybag or belly band as confirmed.”
Add a sample hierarchy: “Lab dip and uncoated fleece handfeel approved first; EVA dot strike-off approved second; decorated pre-production sample approved third; bulk must match the sealed PP sample for shade, handfeel, dot geometry, odour, folding and packing.” Retain one sealed PP sample with the buyer, one with the factory QC room and one with the production line supervisor.
State tolerances clearly: base fleece GSM +/-5%; finished size +/-3% after relaxation; skew not over 2.5% of length; coating add-on +/-5gsm against approved standard; dot diameter +/-0.5mm; pitch +/-1.5mm; shade difference commercially acceptable against approved lab dip, with stricter ΔE only if the buyer provides an instrument standard and illuminant.
Limit claims: “Anti-slip performance tested on agreed seat substrate by FG-01 incline method. Product is not waterproof, not a safety restraint, not guaranteed for all seat angles or contaminated surfaces, and not intended for high-temperature industrial laundering.” That wording protects both buyer and mill from claims the construction cannot support.
For low-MOQ or mixed-SKU programs, align this PO wording with realistic ordering economics. Related ordering guidance is covered in low MOQ startup blanket sourcing and custom blanket lead times and shipping.
Production controls on the coating line
The coating process should be locked before bulk cutting. Key controls are fleece face/back orientation, brushing and shearing level, fabric relaxation, web tension, compound viscosity, dot-screen or roller condition, application temperature, curing or cooling zone, line speed and winding pressure. A stable dot pattern on the first 50 metres does not prove the next 5,000 metres will match.
Inline QC should check the first bulk roll, then at least every 500-1,000 metres or every lot change, whichever comes first. Record dot diameter, pitch, add-on by panel weight, handfeel, strike-through, tackiness, odour, colour, missing-dot lanes, roll edge build-up and face contamination. For smaller custom lots, check every roll because setup drift is a larger share of production.
Corrective actions must be defined. If dots are smeared, reduce viscosity drift, check roller pressure and confirm curing/cooling. If dots shed, check fleece back cleanliness, nap height, curing temperature, dwell time and compound age. If dots strike through to the face, reduce pressure or add-on and confirm fleece density. If blocking appears during winding, lower winding tension, extend cooling or add interleaving for trials before bulk packing.
Cutting and sewing also affect anti-slip performance. Overlock settings that stretch the fleece can create edge curl after washing. Heavy embroidery can compress dots on the reverse during packing. Heat-transfer logos can soften nearby dots if applied after coating. If decoration is heavy, test the complete decorated blanket, not a blank fabric panel. For decoration method trade-offs, see custom blanket decoration methods.
Inspection plan and AQL defect definitions
Use final inspection to catch both textile defects and coating-specific failures. A common arrangement is ANSI/ASQ Z1.4 or ISO 2859-1, General Inspection Level II, with AQL 0 for critical defects, 2.5 for major defects and 4.0 for minor defects unless the buyer’s manual is stricter. For broader blanket inspection structure, see blanket quality control inspection.
Critical defects should include contamination by sharp metal, mould, live insects, wrong fibre content label, severe chemical odour, prohibited claim on label, unsafe packaging for the target age group, or any test failure required by law or buyer manual. Critical defects are normally reject-and-hold, not repair-and-ship.
Major defects should include dot shedding when rubbed by hand, tacky or uncured dots, dot transfer to the fleece face or polybag, blocking between folded surfaces, odour above approved standard, coating strike-through visible on the face, uncoated lanes wider than 20mm, uneven add-on causing clear grip variation, size outside tolerance, skew over agreed limit, edge curl that prevents flat folding, decoration cracking, wrong care label, shade variation outside approved standard, carton staining and wet or crushed cartons.
Minor defects may include a small number of isolated missing dots, light lint, slight thread tails, small overlock irregularities, minor fold-line flattening that recovers after 24 hours, or shade variation within the approved range. Minor does not mean ignored; repeated minor defects across many cartons can indicate process drift and should trigger a line check.
Sampling should include carton-opening checks from top, middle and bottom pallet positions when possible. Inspect both freshly opened units and units left open for 24 hours after unpacking, because pressure marks and fold-line flattening may recover. If they do not recover, treat them as packing or compression defects, not normal presentation variation.
Packing-ageing test before shipment
EVA dots can pass lab handling and still fail after warm, compressed shipping. Add a packing-ageing test before mass packing is frozen. Pack blankets exactly as bulk: same fold, polybag, belly band, carton size, quantity per carton and pallet pattern.
A practical internal ageing condition is 7 days at 40°C and 75% RH with a top-load equivalent of 3-5 stacked export cartons, or the buyer’s expected warehouse/container condition if stricter. For a faster screen, run 72 hours at 50°C without humidity control, but do not treat it as equivalent to real transit ageing. Include one carton from the first production lot and one from the approved PP packing trial.
Acceptance after ageing: no dot-to-face transfer, no dot-to-polybag transfer, no blocking that requires force to open, no carton staining, no strong odour after opening, no permanent pressure marks visible from 1 metre, fold-line flattening recovering substantially within 24 hours, and no measurable loss of FG-01 seat-grip performance compared with the unaged PP sample. If dots stick to polybag film, change bag grade, reduce residual tack, add cooling time before folding or reconsider the compound.
Avoid tight vacuum compression for EVA-dotted fleece unless validated. Compression can flatten dots into plates and create glossy face marks. For freight cube reduction, reduce blanket size, refine fold method or use carton optimisation before compressing the anti-slip surface. If the program is highly freight-sensitive, compare construction economics with lighter airline-style fleece blankets such as travel and airline blanket weight packing.
Failure-mode table for buyer review
Use the table during sampling calls and pre-production meetings. It turns vague “anti-slip quality” into observable risks and corrective actions.
| Failure mode | Likely cause | How to catch it | Corrective action |
|---|---|---|---|
| Blanket slides on glossy seat | Low add-on, wide pitch, hard compound, contaminated seat | FG-01 clean, wet and dusty variants | Tighter pitch, softer compound, silicone validation, claim limitation |
| Dots shed after wash | Poor anchoring to fleece back, over-brushed nap, under-cure | ISO 6330 wash plus dot-count loss | Adjust cure, reduce nap height, improve pre-cleaning, change compound |
| Dots block in carton | Residual tack, hot packing, high pressure, unsuitable polybag | 7-day 40°C/75% RH packing-ageing test | Extend cooling, lower add-on, change bag film, reduce carton load |
| Face shows glossy marks | Strike-through, fold pressure, over-heavy dots | Face inspection after ageing and unpacking | Reduce pressure/add-on, adjust fold, improve fleece density |
| Strong odour after opening | Compound, filler, packaging or trapped process volatiles | 24-hour 40°C sealed-bag odour screen | Change compound batch, air before packing, review packaging film |
| Logo cracks or distorts dots | Heat transfer or embroidery applied without compatibility check | Decorated full-blanket wash and fold test | Move logo, change decoration method, decorate before/after coating as validated |
Supplier audit questions should be specific: What is the compound code and shelf life? How is viscosity checked and recorded? What is the screen or roller specification? What is the standard line-speed window? How often is add-on measured? How are first-off, middle-run and last-off panels retained? What is the corrective action if dot add-on drifts by more than 5gsm? Who signs the sealed PP sample on the production floor?
Commercial and logistics notes
Incoterms change what the buyer must control. Under EXW or FCA, the buyer should confirm local trucking and consolidation do not expose cartons to unnecessary heat or compression. Under FOB Ningbo or Shanghai, the factory controls export carton readiness up to loading but not destination storage. Under CIF or DDP, carton cube, pallet height, HS classification, destination testing and chargeback terms need earlier agreement.
Carton planning should include finished piece weight, bag or band weight, carton quantity, gross weight and cube. A 130 x 150cm 200gsm fleece with 30gsm dot add-on has about 449g of textile/coating before edge thread, labels and packing. Real packed piece weight may sit higher depending on overlock, decoration and packaging. Do not use fabric weight alone for freight costing.
If the blanket is part of a retail or promotional kit, test the full pack. EVA dots can transfer to printed belly bands, PVC zipper bags, dark heat-transfer logos or coated paper inserts. Keep anti-slip dots away from printed surfaces during folding, or validate with the packing-ageing test. For mixed packing and shipping lead-time planning, see custom blanket lead times and shipping.
Frequently asked
What EVA dot add-on should we specify for a 200gsm anti-slip fleece stadium blanket? A practical starting range is 18-45gsm dry add-on. Use 18-25gsm for low-cost giveaways, 28-35gsm for normal retail stadium blankets, and 32-45gsm only after packing and wash validation. Higher add-on can increase grip, but it also raises blocking, pressure-mark and stiffness risk.
What dot size and pitch are realistic for fleece backing? For 200gsm polar fleece, start with 2.5-4.0mm dot diameter and 8-12mm centre-to-centre pitch. Dots below about 2.5mm may sink into brushed nap; dots above about 4.5mm may spread or crack. Very tight pitch increases add-on and blocking risk, while wide pitch can slide on curved seats.
How should anti-slip performance be tested? Use a defined incline-plane method such as FG-01: 300 x 300mm swatch dotted side down on agreed seat substrate, 5kg load over 250 x 250mm contact area, 10-minute dwell at 15°, no slide over 20mm on a clean surface. Add wet and dusty variants for real stadium use, and repeat after washing for retail claims.
What wash test is reasonable for EVA-dotted fleece? Use ISO 6330 domestic washing at 40°C mild cycle with agreed non-bleach detergent, followed by line dry or low-tumble dry as stated on the care label. After 3 cycles, a practical acceptance level is no more than 3% dot loss in a 300 x 300mm area, no large bare patch, no tackiness, and at least 80% post-wash grip retention versus the approved sample.
Is EVA dot backing waterproof? No. EVA dots improve seat grip but do not form a continuous waterproof barrier. For damp grass, beach or picnic use, specify PEVA, PU, TPU, Oxford, aluminium film or foam-backed mat construction instead of increasing EVA dot weight.
When should we choose silicone instead of EVA? Choose silicone or validate it when the program needs repeated laundering, higher heat resistance, premium warranty exposure, long hot-container routes, steep glossy seats or high compression packing. Silicone usually costs more and may have higher process requirements, but it is more robust than EVA for heat and wash ageing.
What are major inspection defects for EVA-dotted fleece blankets? Major defects include dot shedding, tacky or uncured dots, dot transfer, blocking, strong odour, coating strike-through, long missing-dot lanes, uneven add-on, out-of-tolerance size, excessive skew, edge curl, decoration cracking, carton staining and shade variation outside the approved standard.
What should be sealed before bulk production? Seal the lab dip, uncoated fleece reference, EVA dot strike-off, decorated pre-production sample, care label, packing method and carton. Keep retained samples with the buyer, factory QC room and line supervisor so bulk disputes can be checked against the same hierarchy.
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