Silicone Patch FAQ

A cracked workwear patch is telling you a different story from a peeling one. Peeling is a failure of the interface: the patch came away from the fabric. Cracking is a failure inside the silicone: the patch is usually still bonded, often well bonded, but the face has split along the relief or developed a fine web of lines across the base. That single observation matters because it removes the adhesive conversation entirely. Replacing the adhesive will not fix a cracking patch, and neither will a stronger bond. The fix lives in geometry, ageing behaviour and cure state. Start with a failure map, not a cause list ObservationFailure typeWhere the problem usually lives Patch separates, silicone underside cleanAdhesion failureBond line, press settings or fabric finish Perimeter free, centre still bondedEdge liftingGeometry, thickness, strain at the perimeter Face splits along or beside raised letteringCrackingRelief geometry, shoulder radius, formulation flexibility Dense surface crazing with no clear originMaterial fatigue or under-cureCompound and cure cycle Shape changed, corners curl, dimensions openDeformationCompound, thickness, heat history Five results get called "the patch broke" in an inspection room, and they have different owners. Writing them into separate columns is the most useful thing you can do before contacting a supplier. Workwear patches face abrasion, heat and chemistry at the same time. Is industrial laundering worse than home washing for silicone patches? The difference is not only frequency. ISO 15797:2017 specifies test procedures and equipment for evaluating workwear intended to be laundered industrially, and it is explicit about the limits of laboratory simulation: because reproducing an industrial laundry process in a laboratory is often impractical, the standard uses intermediate-scale equipment and defined procedures, and it advises that testing in the actual industrial equipment and process is advisable when finally determining product and process compatibility. For a patch, that advice is the whole story. A programme validated on a domestic cycle and then shipped into an environment with tunnel finishing, high-temperature drying and aggressive mechanical action has validated the wrong process. Four stress mechanisms are worth tracking separately, because each one has a different remedy: Mechanical: drum agitation, garment-to-garment friction, repeated bending at seams and pocket edges Thermal: high wash temperature plus drying or tunnel finishing heat Chemical: alkaline detergents, bleach systems where used, and the residue they leave Flexural: repeated bending of a patch that has already been aged by the three above Cracking starts at the geometry, not the compound Section a cracked patch and look at the origin of the split. The same candidates appear in the same order of frequency. The shoulder of the relief. A raised logo edge with a near-vertical wall and a small radius is a stress riser. Under bending, material on the outside of that shoulder is strained far more than the flat land beside it, and fatigue concentrates into a line a fraction of a millimetre wide. Once that line cracks, it propagates along the relief or down through the base. The fine-detail zone. Thin strokes, narrow gaps between letters and any feature where the section becomes thin behave as the weakest link: less material, less ability to absorb bending, and a shorter path for a crack to travel. The transition between thick and thin. Where a base web meets a tall raised element, stiffness changes abruptly, and abrupt changes are where strain localises. In mould terms this is the draft and radius argument, and it is normally settled before the compound is chosen. This is why the fastest crack fix is sometimes a drawing change: a larger shoulder radius, relief height reduced by a few tenths of a millimetre, a stroke widened enough to carry stress. The brand mark is preserved; the stress path is not. Complex logos put more geometry into the patch, and every transition is a potential crack origin. Two ageing channels, measured separately Silicone has a deserved reputation for heat stability, and that reputation is sometimes used to argue that thermal ageing cannot be the problem. The reputation concerns bulk material. What fails first is thin sections and the bond line. Published material data shows how small the thermal changes can be on a well-cured compound, and simultaneously how large they can be on a marginal one. On a typical 70 Shore A silicone rubber datasheet, heat-resistance testing at 225 °C for 70 hours produced a hardness change of 4 points, no change in tensile strength and a 3 percent change in elongation. The same document reports a compression set of 9 percent after heat ageing at 175 °C for 22 hours, and quotes an operating temperature range tested from -50 to +225 °C. Against those numbers, a laundry tunnel is not an extreme thermal environment for the material. Fluid exposure is a separate channel with its own numbers. In the same datasheet, immersion in a reference oil at 150 °C for 70 hours changed hardness by 3 points, tensile strength by 3 percent, elongation by 7 percent and volume by 4 percent, while water at 100 °C for 70 hours changed hardness by 2 points and volume by 3 percent. Detergent solutions are not aggressive in the way solvents are, but immersion with mechanical action at elevated temperature is a different regime from a drip test, and the property changes that matter for a patch show up as stiffness and surface change rather than obvious swelling. The international framework for these two channels is separate as well. Accelerated ageing and heat resistance testing is standardised in ISO 188:2023, which distinguishes accelerated ageing from heat resistance testing at a service temperature. Chemical exposure follows ISO 1817:2026, which evaluates the resistance of vulcanized and thermoplastic rubbers to liquids by measuring properties before and after immersion. Run them as two experiments, not one: a patch that survives heat but changes after detergent immersion has a different fix from one that survives chemistry and embrittles in the tunnel. A common finding Insufficient post-cure is an under-appreciated cause of cracking. Published reference processes for solid silicone rubber use a press cure followed by a separate post cure, for example a press cure at 170 °C for 12 minutes followed by a post cure at 120 °C for one hour. Post cure removes residual volatiles and stabilises the section. If those fractions remain, they can migrate over time, and thin sections and bond lines are where that shows first. A cracking pattern that is dense, uniform and not centred on any geometric feature is worth investigating as a cure-state issue rather than a design issue. Are thicker silicone patches more crack resistant? A thinner base web bends more easily, so it puts less stress on the relief shoulder and on the bond line during flexing. A thicker base web carries the same relief but resists bending, pushing more strain into the geometry transitions, which is exactly where cracks begin. Relief height compounds it: a tall raised logo on a thick base is the stiffest possible configuration, and stiffness is what fatigue exploits. Thickness should be chosen for the visual and tactile requirement, the mould's ability to fill the detail, and a comfortable match to the fabric's stiffness. Peer specifications for this product family sit around 1 mm for 3D patches and up to a 1.5 mm printed limit. Material data explains why going thicker is not a shortcut: silicone rubber is described in its own datasheets as having poor tensile strength, tear resistance and abrasion resistance, so durability comes from the fatigue behaviour of the formulation, from smooth transitions and from a consistent cure. Where cracks appear, and what that points to Crack locationLikely causeWhat to adjust first Along the shoulder of raised letteringSharp transition, insufficient shoulder radiusMould geometry and relief height Across narrow strokes or fine detailToo little section to carry bendingArtwork: widen the stroke or reduce depth At corners of an angular logoStress concentration at a sharp cornerCorner radius Uniform fine crazing across the faceMaterial fatigue or incomplete cureFormulation and cure cycle Only after high-temperature dryingThermal exposure of a thin sectionHeat-resistance testing at service temperature After bending at a seamFlexural fatigue at a high-strain locationCompatibility of flexibility and placement Test the aged patch, not the new one: cracking is cumulative. A durability test that answers workwear questions 1. Baseline inspection Appearance, dimensions, surface and edges, photographed at a fixed magnification so later stages are comparable. 2. Launder to the real process Use the customer's washing conditions. If the garment will be tunnel finished, test that route, not a domestic cycle. 3. Dry and finish as the customer does Thermal load at this stage is often the deciding factor for a thin section. 4. Flex the aged patch Bend it repeatedly around a radius that matches the garment's use, then inspect for cracking. 5. Inspect against the failure map Record cracks, surface splitting, edge lifting, deformation and adhesion separately, then run the sequence again to the agreed endpoint. Limits worth stating Silicone heat-transfer markings are not compatible with every laundry route. Peer application instructions exclude dry cleaning and chemical wash routes including bleach, enzyme wash and stone wash, and advise against ironing or steaming directly on the transfer or scratching it with metal or fingernails. If the workwear care protocol includes any of those routes, the patch has to be tested against them. Where the garment is re-pressed after a wash, remove detergent residue first: bonding over residue reproduces the previous failure. FromRubber is a custom silicone manufacturer in Dongguan, China: Dongguan Bohao Electronic Technology Co., Ltd., Jingcheng Road 122, Langxia Village, Qiaotou Town, Dongguan, Guangdong, China. Operating since June 2010, with 32 compression moulding machines across two sites and IATF 16949:2016, ISO 9001:2015 and ISO 14001:2015 certification. If you have a workwear patch that is cracking, send a photograph of the crack origin and the laundry conditions, and we can say whether a design change or a cure change is worth testing first. Email nani@fromrubber.com or karl@fromrubber.com, or reach us on WeChat and WhatsApp at +86 18676210913. Related pages on this site Custom rubber patch products for garment and industrial use Non-fading silicone patches for durable colour retention Durable sew-on silicone patches for caps, bags and jackets Why silicone patch edges lift on stretch fabric Why silicone patches peel off polyester after washing How thick an embossed silicone patch should be Silicone Patch FAQ, the group this answer belongs to Sources ISO 15797:2017, Textiles - Industrial washing and finishing procedures for testing of workwear: https://www.iso.org/standard/65152.html ISO 188:2023, Rubber, vulcanized or thermoplastic - Accelerated ageing and heat resistance tests: https://www.iso.org/standard/80468.html ISO 1817:2026, Rubber, vulcanized or thermoplastic - Determination of the effect of liquids: https://www.iso.org/standard/91331.html ISO 4637:1979, Rubber-coated fabrics - Determination of rubber-to-fabric adhesion - Direct tension method: https://www.iso.org/standard/10594.html Material Properties - Silicone Rubber, MEC (heat-resistance test at 225 °C for 70 hours, compression set after ageing at 175 °C, oil and water immersion results, press and post cure reference process, tear and abrasion limitations): https://mec-uk.co.uk/new-admin/uploads/pdf/Material%20Properties%20-%20Silicone%20Rubber.pdf Custom 3D Silicone Patches, Custom Patch Factory (1 mm thickness, cold peel, aftercare, wash and dry cycle durability): https://www.custompatchfactory.com/product/patches/3d-silicone-patches Heat Transfer Product User Manual, HMJ Silicone Sticker, Dongguan (wash-route exclusions, 24-hour wait before testing, edge handling warnings): https://hmjsiliconesticker.com/wp-content/uploads/2024/02/HMJ-Silicone-Printing-Heat-Transfer-application-instruction.pdf

Edge lifting on sportswear is prevented before tooling, not after. Four decisions control it: how much the patch has to bend to follow the knit, how much free edge the logo carries, how much heat the lightweight fabric receives at the press, and whether the press was validated on the assembled garment or only on a flat swatch. Get those four right and edge lifting becomes an exception rather than a recurring complaint. Get them wrong and no change of adhesive will hold, because the load is being applied to the wrong part of the patch. What is genuinely different about sportswear The fabric list is familiar; what matters is how those fabrics behave differently. Elasticity is high and directional. A circular knit may recover well in both directions; a warp knit or stretch woven may move far more along one axis. A patch that is effectively rigid across the direction of greatest movement will always lift on that edge first. The surface is engineered, not natural. Performance knits are brushed, sanded or finished to manage moisture, and moisture-management finishes are surface treatments by definition. That treated surface is what the adhesive has to wet. Fabric mass is low. Thin knit heats fast and cools fast, so the window between correct activation and over-pressing is narrower than on heavy twill. A recipe validated on a uniform will over-press a performance knit. A flatbed press applies even pressure only when the garment panel is flat. Three fatigue loads, not one LoadWhat it does to the patch edgeWhat it calls for Mechanical: cyclic strain and abrasionWorks the perimeter at the point of highest strain gradient; contact with straps and bags adds abrasionLower bending stiffness, larger corner radii, a full edge land Thermal: repeated drying heatApplies heat while the garment is moving, when the bond is under loadTest the drying method the customer uses, including tumble Chemical and moisture: sweat, detergent and residueWets into any perimeter gap; dried residue sits between fabric and bond line on a re-pressClean before any re-press, and test the real detergent and temperature Abrasion deserves a note of its own. Martindale-type abrasion testing is standardised in ISO 12947-2:2016 for textile fabrics, and the standard is not intended for coated fabrics. A patch on a knit is a coated system, so the fabric's abrasion result does not describe the patch's behaviour. Test the assembly. How does logo shape affect edge lifting on sportswear? Take two logos of the same overall size. One is a solid rounded rectangle; the other spells a word in fine strokes with narrow gaps. The second carries far more free edge per square millimetre of bonded area, which means more places where the strain gradient acts and more entry points for moisture. Nothing is different at the material level; their edge lives are not comparable. That gives a design conversation a number instead of an opinion. When a brand wants fine lettering, the counter-proposal is not "make it simpler", which is subjective, but "this shape carries more perimeter per unit of area", which is measurable and can be traded against thickness, relief height or placement. Colour count is a second design constraint that shows up early in tooling. Peer specifications for this product family recommend no more than six colours on printed silicone, and no more than two on moulded silicone, because additional colours raise production difficulty and the failure rate. A sportswear logo that needs five colours printed over deep relief is asking for two difficult things at once. Sleeve and side-panel placements need a lower profile than a flat chest panel. Placement on the body is not placement on the table Press validation usually happens on a flat platen with flat fabric. On the garment, the patch may sit on a shoulder curve, over a raglan seam, across a wrapping side panel, or on a tapering sleeve. There the platen cannot develop uniform pressure and the surface is not planar, so the patch ends up well bonded in the middle and lightly bonded around part of the perimeter. It passes a flat test. It fails in wear. On sportswear, where much of the branding sits on sleeves and side panels, this is not an edge case. Two responses: validate on the assembled garment rather than on a swatch, and consider moving the placement. A logo that is equally legible 10 mm further onto a flat panel will behave completely differently, and that change is free. Where the platen cannot reach, the perimeter never fully bonds. How should a sportswear patch be tested before mass production? 1. Apply on production fabric and production geometry On the assembled panel, with production settings. Peer application instructions are explicit that fabrics and thicknesses differ and that the factory must confirm press parameters and washing standards on its own samples. 2. Respect the cooling step One published instruction calls for a cold peel with the fabric laid flat for 15 minutes to reach ambient temperature before the film is removed, and warns against bending the garment during that time. 3. Wait before washing Published waiting times before any physical or washing test range from a minimum of 24 hours to at least 48 hours. The bond needs to develop before it is judged. 4. Stretch, wash, dry, stretch again Stretch to the extension seen in wear, then wash at the customer's temperature with the customer's detergent, then dry the way the customer dries, then stretch once more before inspecting. That last stretch is where real failures appear. 5. Report each failure mode separately Edge lifting, partial detachment, cracking, deformation and appearance change are five different results, not one pass or fail. Combining them hides which axis is failing. Limits worth stating Silicone heat transfers are not a universal answer. Peer application guidance excludes dry cleaning and chemical laundry routes such as bleach, enzyme wash and stone wash, and advises against pressing or steaming directly on the transfer. Some manufacturers also advise against heat-transfer application on delicate substrates such as silk or fine knit beanies, because the heat itself damages the fabric. Where the garment must survive those routes, the patch has to be validated against them rather than assumed. Movement over a garment's life, and why stiffness matters A training top is washed more often than a jacket, worn closer to the body, stretched further, wetted with sweat from the inside and dried at higher heat than care labels usually admit. Each of those is a small load. What matters for the patch is that they repeat, and that the knit does not return perfectly to its starting dimensions after each cycle. Why a lower-profile patch helps is mechanical. For a plate bonded to a flexible substrate, bending stiffness rises roughly with the cube of thickness, so small reductions in base web thickness produce large reductions in the load carried at the perimeter. Industry-published specifications for this product family sit around 1 mm for 3D patches and up to a 1.5 mm limit for printed silicone. Beyond that band, extra thickness buys visual depth and costs edge durability. Published silicone material data supports the same conclusion from the other side. Silicone rubber keeps its properties across a very wide temperature range, with heat-resistance testing at 225 °C for 70 hours producing only a few points of hardness change, but the same datasheets describe silicone as having poor tear resistance and abrasion resistance. A patch that is thermally robust can still be mechanically fragile at a thin edge. Durability comes from geometry and cure, not from mass. FromRubber is a custom silicone manufacturer in Dongguan, China: Dongguan Bohao Electronic Technology Co., Ltd., Jingcheng Road 122, Langxia Village, Qiaotou Town, Dongguan, Guangdong, China. Operating since June 2010, with 32 compression moulding machines across two sites and IATF 16949:2016, ISO 9001:2015 and ISO 14001:2015 certification. If you are developing a patch for a performance knit, send the fabric details, the logo and the wash requirements, and we will tell you which geometry is likely to lift first. Email nani@fromrubber.com or karl@fromrubber.com, or reach us on WeChat and WhatsApp at +86 18676210913. Related pages on this site Custom heat transfer patches for performance and casual apparel Soft waterproof silicone heat transfer patches for clothing and badges Silicone heat transfer patch manufacturing in China, a 2026 review on this site Why silicone patch edges lift on stretch fabric Why silicone patches peel off polyester after washing Silicone Patch FAQ, the group this answer belongs to Sources ISO 12947-2:2016, Textiles - Determination of the abrasion resistance of fabrics by the Martindale method - Part 2: Determination of specimen breakdown: https://www.iso.org/standard/61058.html ISO 6330:2021, Textiles - Domestic washing and drying procedures for textile testing: https://www.iso.org/standard/75934.html Impact of the Elastane Percentage on the Elastic Properties of Knitted Fabrics under Cyclic Loading, 2022: https://www.mdpi.com/1996-1944/15/19/6512 Custom Silicone Patches for Clothing Labels, Jin Sheu (thickness limit, colour count guidance, backing options): https://www.jinsheu.com/en/category/custom-silicone-patches.html Custom 3D Silicone Patches, Custom Patch Factory (1 mm thickness, 150 to 160 °C for 25 to 30 seconds, cold peel, 48-hour wait before washing): https://www.custompatchfactory.com/product/patches/3d-silicone-patches Heat Transfer Product User Manual, HMJ Silicone Sticker, Dongguan (cold peel, 15-minute flat cooling, 24-hour wait, wash-route exclusions, delicate-substrate caveats): https://hmjsiliconesticker.com/wp-content/uploads/2024/02/HMJ-Silicone-Printing-Heat-Transfer-application-instruction.pdf Material Properties - Silicone Rubber, MEC (wide service temperature range, heat-resistance results, tear and abrasion limitations): https://mec-uk.co.uk/new-admin/uploads/pdf/Material%20Properties%20-%20Silicone%20Rubber.pdf How To: 3D Silicone Heat Transfers, Stahls' UK (high-build raised construction, stretch resistance, shape retention after repeated washing): https://www.stahls.co.uk/blog/how-to-3d-silicone-heat-transfers.html

Edge lifting on stretch fabric is not a weak adhesive. It is a stiffness mismatch. A silicone patch is a plate and a stretch knit is a membrane, and the only place the difference between them can express itself is the bond line at the perimeter. That is why the patch stays bonded over most of its area while one or two points on the edge open and close with the fabric. The fix is to reduce the differential movement between patch and fabric, which means thickness, flexibility, edge geometry and placement, in that order. Increasing bond strength alone rarely holds. Why the load lands on the perimeter Over the middle of the patch, the fabric is held and largely cannot stretch. At the perimeter, the fabric is free on one side and held on the other, so the transition from free to held happens across a couple of millimetres. That is where the strain gradient is steepest, which is why the edge lifts first. The edge is not weaker; it is doing more work per unit area than any other part of the patch. Cyclic loading makes it worse over time. Research on elastic knitted fabrics under cyclic loading shows that loading and unloading curves do not coincide: there is hysteresis and an amount of unrecovered elongation that depends on elastane content and on how far the fabric is taken past its elastic region. The practical consequence for a patch is a slow accumulation of slack, so the perimeter is asked to absorb slightly more differential movement every week. That is the mechanism behind the complaint that is so hard to answer: the same patch was fine for two years and now it lifts. The patch did not change; the number of cycles went up. Edge geometry, not the logo face, decides where a patch starts to lift. Does a thicker silicone patch stop the edges lifting? For a plate, bending stiffness rises steeply with thickness, roughly with the cube rather than in proportion. Halving the base web thickness reduces resistance to bending by something close to eight times, depending on construction. That stiffness has to go somewhere, and where it goes is the bond line at the perimeter, which now has to hold a lever that is much harder to bend. Peer specifications put the working range in context. One manufacturer publishes a 1 mm thickness for its 3D silicone patches, describing it as the balance between flexibility and a pronounced 3D effect. Another publishes printed silicone from flat up to a 1.5 mm limit, with moulded silicone at 1.5 mm and above. In other words, the industry band for printed and lightly raised apparel work sits around 1.0 to 1.5 mm, and going above it is a decision about visual depth rather than durability. Material data explains the rest of the mismatch. A typical 70 Shore A silicone datasheet lists elongation at break of 150 percent as the requirement, with 266 percent achieved on test, against tensile strength around 5.0 to 5.7 MPa. Knitted fabric with elastane in it can move far further than that in normal wear. The patch does not need to match the knit, but the bond line has to survive the difference, and a thinner, more compliant patch leaves less difference to absorb. Shape decisions that decide edge life Design decisionEffect on edge stressPractical direction Corner radiusSharp corners concentrate stress where two free edges meetRound corners generously in the artwork before the tool is cut Narrow projectionsVery little bond area behind a lot of moving perimeterWiden or shorten fine details where the brand allows Relief shoulder profileA vertical wall concentrates bending on one lineUse a gradual shoulder instead of a step Edge land widthA flat ring of contact keeps the peel front away from the reliefKeep a continuous land all the way around Perimeter to area ratioFine, intricate logos carry far more free edge per unit of bonded areaTrade detail against thickness or relief height, not against nothing That last row is the one most often missed. Two logos of the same overall size are not comparable at the material level if one is a solid rounded shape and the other spells a word in fine strokes. The second has more free edge, more entry points for moisture, and more opportunities for the knit to work the perimeter loose. A thin, low-profile label bends with the knit instead of levering against it. Edge lifting that is created at the press Some edge lifting is manufactured on day one, and it is easy to separate from fatigue because it is visible immediately. Pressure too low, so the relief edges never fully contact the fabric and the bond exists only under the flat areas Temperature too low, so the adhesive reaches tack rather than full activation at the outer perimeter Dwell too short for heat to travel to the edge land of a thick patch Uneven pressure from a small platen, or from pressing a curved garment area with a flat platen Placing the patch over a seam, so part of the perimeter is only touching rather than being pressed into the fabric Removing the carrier film while the bond is still hot Peer application instructions handle that last point with numbers. One manufacturer specifies a cold peel and advises laying the fabric flat for 15 minutes so it reaches ambient temperature before the film is removed, adding that the fabric and label should not be bent during that period. The same document allows a hot peel only if the film is removed within 5 seconds. Those are not interchangeable: the peel method is part of the specification, not an operator preference. The same source sets a stretch-test rule that is worth copying into your own procedure: do not stretch the transfer from the centre of the print, grab at least 5 cm away from it. Pulling from the centre loads the bond in a direction the garment never applies and produces a failure that has no field equivalent. Where the patch lands is decided by hand long before the wash cycle tests it. How should edge durability be tested on stretch fabric? 1. Apply on production fabric in production geometry If the patch will sit on a curve or a seam, replicate that. A flat test piece overstates edge performance. 2. Characterise the fabric, then test at working extension Tensile testing of fabrics with elastomeric fibre follows the strip method in ISO 13934-1:2013, and the standard notes it is not normally applicable to coated fabrics. Use it on the fabric, then test the patch at the extension the garment actually sees. 3. Cycle, wash, dry, then stretch again The stretch after drying is the step most routines skip and the one that finds real failures. 4. Score edge lifting separately from adhesion Two columns: how much of the perimeter has lifted, and whether the patch is still attached over the bonded area. They fail at different stages. Limits worth stating Silicone itself is a poor performer in three respects that matter here: silicone rubber data sheets describe it as having poor tensile strength, tear resistance and abrasion resistance. On stretch fabric those weaknesses show up at the perimeter, not in the middle. Where a garment sees sustained high extension plus abrasion, a thinner and more compliant patch reduces both loads. Silicone material data, such as the tensile and elongation values determined under ISO 37:2024, describes the compound; it does not describe the patch on a knit. What should be fixed first when the edges lift? Confirm the peel and cooling procedure at the press, because it is free to fix Check placement, and move the logo onto the flattest available area of the panel if the brand allows Increase corner radii and confirm a continuous edge land in the artwork Reduce base web thickness to the lower end of the working range, and reduce relief height where the brand allows Re-test on production fabric with the real wash and dry cycle Only then discuss formulation changes with the supplier Teams that start at step six usually arrive at step one several trials later, having paid for tooling in between. Lower thickness is usually the cheapest durability change available. FromRubber is a custom silicone manufacturer in Dongguan, China: Dongguan Bohao Electronic Technology Co., Ltd., Jingcheng Road 122, Langxia Village, Qiaotou Town, Dongguan, Guangdong, China. Operating since June 2010, with 32 compression moulding machines across two sites and IATF 16949:2016, ISO 9001:2015 and ISO 14001:2015 certification. Silicone labels, patches and heat-transfer markings for apparel are among our main custom lines. Send us the artwork, the fabric details and the wash-and-wear expectation, and we can flag the geometry that is likely to lift first. Email nani@fromrubber.com or karl@fromrubber.com, or message us on WeChat and WhatsApp at +86 18676210913. Related pages on this site Custom silicone labels with thickness and edge options Waterproof silicone labels for outdoor gear, where flexing and moisture combine Silicone patches and garment labels built to garment specification Why silicone patch edges lift on stretch fabric Silicone Patch FAQ, the group this answer belongs to Sources ISO 13934-1:2013, Textiles - Tensile properties of fabrics - Part 1: Determination of maximum force and elongation at maximum force using the strip method: https://www.iso.org/standard/60676.html ISO 37:2024, Rubber, vulcanized or thermoplastic - Determination of tensile stress-strain properties: https://www.iso.org/standard/86892.html Impact of the Elastane Percentage on the Elastic Properties of Knitted Fabrics under Cyclic Loading, 2022: https://www.mdpi.com/1996-1944/15/19/6512 Modification of Surface Energy and Wetting of Textile Fibers, Ferrero and Periolatto, IntechOpen, 2015: https://www.intechopen.com/chapters/48818 Custom 3D Silicone Patches, Custom Patch Factory (1 mm thickness, pressing and aftercare parameters): https://www.custompatchfactory.com/product/patches/3d-silicone-patches Custom Silicone Patches for Clothing Labels, Jin Sheu (printed limit 1.5 mm, moulded 1.5 mm and above, backing options): https://www.jinsheu.com/en/category/custom-silicone-patches.html Heat Transfer Product User Manual, HMJ Silicone Sticker, Dongguan (cold peel, 15-minute flat cooling, 5 cm stretch-test rule): https://hmjsiliconesticker.com/wp-content/uploads/2024/02/HMJ-Silicone-Printing-Heat-Transfer-application-instruction.pdf Material Properties - Silicone Rubber, MEC (70 Shore A hardness, elongation at break, tear and abrasion limits): https://mec-uk.co.uk/new-admin/uploads/pdf/Material%20Properties%20-%20Silicone%20Rubber.pdf

Most silicone patch peeling on polyester is a bond-line problem, not a patch defect. The adhesive never fully wet the fibre, so the patch was only partly attached before it reached the first wash. You can confirm that in one look: if the adhesive layer travels away with the patch and the fabric underneath is clean, the bond was under-formed. If the residue stays on the fabric, the patch construction is the suspect rather than the press. Below is the short path through the three things that actually decide the result: substrate, bond formation, and the wash cycle you are testing against. Read the peel surface before changing anything What you seeWhere the failure isWhat it usually means Fabric clean, adhesive travels with the patchAdhesive to fibre interfaceUnder-formed bond: temperature, dwell time or a fabric finish Adhesive stays on the fabric, silicone liftsSilicone to adhesive interfaceBacking system not matched, or bond line contaminated Adhesive torn, residue on both surfacesInside the adhesive layerBond formed, then fatigued by washing, drying heat or stretch Patch intact, fibres pulled out of the fabricThe fabric itselfBond is stronger than the substrate Photograph both surfaces at the same magnification every time you run this check. A photographed baseline is what lets you compare one season against the next instead of arguing from memory. The wash cycle loads the patch perimeter far more than the patch centre. Why polyester is the difficult substrate Polyester is hydrophobic and comparatively smooth, which is exactly why it is popular in sportswear. Published work on PET fibre modification states the same problem from the finishing side: the low hydrophilicity of PET fabrics causes difficulties in finishing and, in the authors' words, low adhesion to plastics and rubber. That is a material-level handicap, and a hotter press does not remove it. Surface energy decides how well a molten adhesive wets the fibre. No wetting means no bond, however long the platen stays down. This is also why fabric finishes matter: softeners and water-repellent treatments are designed to change the fibre surface, and some of them reduce surface energy, which is the opposite of what a heat-transfer bond needs. Test it in one afternoon. Press identical patches onto grey goods and onto finished, softened fabric, then wash both. If grey goods survive and the finished fabric fails, the finish is your variable. Repeated wetting and squeezing works detergent into any gap at the perimeter. How long should the carrier film stay on before it is peeled? The first clock is dwell time under load, the one everybody writes down. The second is cooling time before the carrier film comes off, and it is where a lot of peeling starts. A heat-transfer adhesive does not reach full strength while it is still hot. Strip the film warm and the adhesive is drawn toward the film instead of being held by the fibre, which pre-loads the interface before the garment is even folded. Peer-published application data makes both clocks explicit, and it is worth noting that the published numbers do not agree with each other. That disagreement is the practical lesson. Peer-published parameterManufacturer A (Dongguan)Manufacturer B Press temperature155 to 160 °C150 to 160 °C, up to 170 maximum Pressure2 to 4 kg4 kg, raised to 4.5 kg if needed Dwell time15 to 20 seconds25 to 30 seconds Film removalCold peel; lay flat 15 minutes to reach ambient temperature before peelingCold peel after the patch cools completely Waiting time before washingMinimum 24 hoursAt least 48 hours Two experienced manufacturers publish dwell times that differ by ten seconds and waiting times that differ by a full day. That is not an error; it reflects different adhesive systems and different reference fabrics. It is the reason a supplier's sample data cannot be transferred straight onto your fabric, and the reason a cooling time that exists only in the operator's head is a production risk. One more thermal point worth knowing: a standard silicone rubber datasheet typically quotes a service range of about -60 to +200 °C, and heat-resistance testing at 225 °C for 70 hours shows only a few points of hardness change. Drying heat is therefore rarely what damages the silicone. What it damages is the bond line and the edge geometry around it. Which wash cycle should a silicone patch be tested against? Domestic laundering procedures are standardised precisely because the parameters change the answer. ISO 6330:2021 defines reference machines, detergents and ballast loads together with a set of washing procedures and six drying procedures, and its own note states that using a different machine type, detergent or dryer type can affect the result. Two suppliers can both report a passing result and both be right, while your garment fails, because neither test reproduced your temperature, detergent, drum load or drying heat. Colour-fastness laundering standards make the same point from another direction. ISO 105-C06:2010 describes single and multiple test cycles and notes that a multiple test may correspond to up to five domestic or commercial launderings at temperatures not exceeding 70 °C, with severity coming largely from increased mechanical action. Mechanical action, not chemistry, is often what finishes off a marginal patch bond. For the patch itself, the closer analogue is a coated-fabric adhesion test. ISO 4637:1979 exists for a thin rubber layer bonded to fabric, where conventional peel methods are difficult, and it notes that a direct-tension result does not necessarily correlate with a peel test. A peel value and a tension value are not interchangeable numbers. Carrier removal is a step in the bond, not a cleanup step after it. Limits worth stating Silicone heat-transfer labels are not suitable for every laundry process. Peer application instructions exclude dry cleaning and chemical wash routes such as bleach, enzyme wash and stone wash, and warn against pressing or steaming directly on the transfer or scratching the edges with metal or fingernails. If your garment care label permits those routes, the patch specification has to be re-tested against them rather than assumed. What to send a supplier before you order Fabric composition and construction, grey or finished goods Weight, thickness and stretch percentage in both directions Any coating, laminate or surface finish, and whether it can change between lots Garment position of the patch, and whether that area is flat or curved Patch dimensions and the smallest feature width in the logo Press temperature, dwell time and the cool-down time your line actually achieves Expected wash cycles, wash temperature, detergent type and drying method A patch supplier can only match a backing system to your process if they know the process. Most bonding failures we see at sample stage trace back to one of those nine items never having been exchanged. FromRubber is a custom silicone manufacturer in Dongguan, China: Dongguan Bohao Electronic Technology Co., Ltd., Jingcheng Road 122, Langxia Village, Qiaotou Town, Dongguan, Guangdong, China. The factory has operated since June 2010, runs 32 compression moulding machines across two sites, and holds IATF 16949:2016, ISO 9001:2015 and ISO 14001:2015 certification. Silicone labels and heat-transfer patches for apparel are one of our main custom lines. If you have a peeling case, the peel-surface photographs plus the fabric details above are usually enough to say whether a construction change or a process change is worth testing first. Email nani@fromrubber.com or karl@fromrubber.com, or reach us on WeChat and WhatsApp at +86 18676210913. Related pages on this site Custom heat transfer silicone patches for pressed garment branding Custom silicone labels and how the construction is specified Silicone heat transfer patch manufacturing in China, a 2026 review on this site Silicone Patch FAQ, the group this answer belongs to Sources ISO 6330:2021, Textiles - Domestic washing and drying procedures for textile testing: https://www.iso.org/standard/75934.html ISO 105-C06:2010, Textiles - Tests for colour fastness - Part C06: Colour fastness to domestic and commercial laundering: https://www.iso.org/standard/51276.html ISO 4637:1979, Rubber-coated fabrics - Determination of rubber-to-fabric adhesion - Direct tension method: https://www.iso.org/standard/10594.html Sustainable Alkaline Hydrolysis of Polyester Fabric at Low Temperature, 2022: https://pmc.ncbi.nlm.nih.gov/articles/PMC8876586/ Modification of Surface Energy and Wetting of Textile Fibers, Ferrero and Periolatto, IntechOpen, 2015: https://www.intechopen.com/chapters/48818 Heat Transfer Product User Manual, HMJ Silicone Sticker, Dongguan (press and wash parameters, storage, wash-route exclusions): https://hmjsiliconesticker.com/wp-content/uploads/2024/02/HMJ-Silicone-Printing-Heat-Transfer-application-instruction.pdf Custom 3D Silicone Patches, Custom Patch Factory (press parameters, thickness, aftercare): https://www.custompatchfactory.com/product/patches/3d-silicone-patches Material Properties - Silicone Rubber, MEC (temperature range, hardness and heat-ageing data): https://mec-uk.co.uk/new-admin/uploads/pdf/Material%20Properties%20-%20Silicone%20Rubber.pdf