World Class Textile Producer with Impeccable Quality

T-Shirt Fabric Guide for Apparel Brands: Jersey, Cotton and Polyester Blends for Bulk Orders

T-Shirt Fabric Guide for Apparel Brands: Jersey, Cotton and Polyester Blends for Bulk Orders
Table of Contents

Key Sourcing Takeaways

  • "T-shirt fabric" describes two separate things: construction (how the yarn is knitted) and fibre content (what the yarn is made of). Both must be specified in your tech pack.
  • Jersey is the standard knit construction for most T-shirt bulk orders — it is lightweight, print-friendly, and cost-effective at scale. Interlock is heavier and more structured, suited to premium or uniform applications.
  • 100% cotton yields the sharpest DTG results but carries the highest shrinkage risk if pre-treatment is not specified in your order.
  • Cotton-polyester blends (CVC or 50/50) reduce shrinkage and improve colour retention across washes — making them a practical default for branded casual T-shirts.
  • Sublimation printing requires high polyester content (ideally 100%) to bond dye correctly. Specifying the wrong fabric construction for your decoration method adds sampling rounds and delays.
  • Lock fibre ratio, GSM range, and pre-shrinkage treatment in your tech pack before sampling begins — fabric changes after sample approval restart the approval process.

Choosing a T-shirt fabric is one of the first decisions a brand makes when developing a new style — and one of the most consequential for bulk production. Get it right and your garments arrive on spec, print as expected, and hold their size through wash cycles. Get it wrong and you face sampling reruns, GSM disputes, print adhesion failures, or — worst case — large-order shrinkage that pushes your finished sizes out of tolerance.

The challenge is that "fabric" in the context of T-shirts covers two separate things: how the yarn is knitted (construction) and what the yarn is made of (fibre content). Each variable interacts differently with print methods, dyeing processes, and mass-production tolerances. Most guides treat these as one topic. This one separates them, because confusing construction with fibre content is exactly how brands end up with misaligned expectations at the sampling stage.

What follows is a production-oriented breakdown of the fabric choices that matter most for T-shirt bulk orders — not which option feels softest, but which option works best for your brand's decoration method, order volume, and quality positioning.

What T-Shirt Fabric Means: Construction vs Fibre Content

When brands ask "what fabric should I use?", they are usually asking two questions at once — and mixing the answers creates problems down the line. Let's separate them cleanly.

Construction: How the Yarn Is Knitted

Construction refers to the knitting structure — the mechanical arrangement of loops that gives a fabric its physical behaviour. For T-shirts, the two most relevant constructions are single jersey and interlock (also called double-knit). Construction determines a fabric's weight range, stretch behaviour, surface texture, edge stability, and sewing characteristics. A single jersey 160 GSM fabric and an interlock 160 GSM fabric will behave completely differently in production even though they share the same weight, because their internal structures are different.

Construction is set at the knitting stage, before fibre content enters the picture. A jersey fabric can be knitted from cotton, polyester, cotton-polyester blends, modal, bamboo, or any combination. The construction stays the same regardless of what the yarn is made of.

Fibre Content: What the Yarn Is Made Of

Fibre content describes the raw material — cotton, polyester, rayon, or a blend of two or more. Fibre content determines dyeability, shrinkage rate, breathability, moisture management, and print surface compatibility. A 100% cotton jersey and a 50/50 cotton-polyester jersey share the same construction but behave very differently when you dye them, wash them, or run them through a DTG machine.

For bulk orders, fibre content affects cost in two directions: raw material price and downstream processing cost. Cotton typically costs more than polyester at the fibre stage but may simplify dyeing and DTG printing. Polyester costs less per kilogram but requires reactive dye systems that some smaller factories may not have set up for your target GSM.

Why Both Must Appear in Your Tech Pack

The practical consequence of this distinction is straightforward: your tech pack needs to specify both construction and fibre content to give your factory a workable brief. Specifying only "100% cotton" without noting the knit construction leaves the factory choosing between single jersey, interlock, piqué, and other options — all of which hit different price points and perform differently under the same sewing conditions.

For brands ordering T-shirts through an OEM partner: specify construction (e.g., single jersey), fibre ratio (e.g., 95% cotton / 5% elastane), GSM range, and any pre-shrinkage or pre-washing requirement. These four data points eliminate the most common source of sampling misalignment.

Jersey and Interlock: Choosing the Right Construction for Your T-Shirt Order

single jersey fabric knit loop structure close-up versus interlock double knit apparel manufacturing
Single jersey (left) has one needle bed and curls at edges; interlock (right) uses two needle beds and produces a dimensionally stable, smooth-sided fabric

Most T-shirts produced at scale use single jersey construction. Understanding why — and when interlock makes sense instead — is foundational to specifying fabric correctly before you engage a factory.

Single Jersey: The Production Default

Single jersey is knitted on a single needle bed using a circular knitting machine. Each needle forms one loop per course. The result is a fabric with a smooth face side (knit loops visible) and a textured reverse side (purl bars visible). The asymmetry of the structure gives jersey several defining production characteristics:

  • Edge curl: Raw-cut edges of single jersey naturally curl toward the face side. This requires specific finishing techniques (covered hem, mock flat-lock, or sufficient hem allowance) and affects pattern efficiency during cutting.
  • Lateral stretch: Single jersey stretches primarily in the horizontal direction, with moderate vertical recovery. This makes it well-suited to relaxed-fit and regular-fit T-shirt silhouettes where movement is needed but structure is not.
  • Print surface: The smooth face side of single jersey accepts screen printing, DTG, and heat-transfer printing without texture interference — making it the preferred construction for branded graphic T-shirts.
  • Cost efficiency: Single jersey requires one needle bed and runs faster on circular knitting machines than double-knit constructions. At equivalent GSM, single jersey is typically lower cost per metre than interlock.

For most T-shirt brands ordering graphic tees, basics, or casual wear: single jersey is the correct construction. It prints well, sews efficiently, and is available in the widest GSM range from most OEM factories.

Interlock: When Structure and Premium Feel Matter

Interlock is produced on a double needle bed machine, creating two interlocked layers of jersey knit back to back. The result is a fabric that looks and feels the same on both sides, behaves more like a woven in terms of dimensional stability, and sits heavier and firmer in hand than a comparable single jersey.

From a production standpoint, interlock changes several parameters:

  • No edge curl: Because both sides are structurally equivalent, interlock does not curl at raw edges. This simplifies cutting and reduces hem allowance requirements.
  • Reduced lateral stretch: The double-knit structure restricts crosswise stretch, which gives interlock better shape retention in fitted silhouettes — useful for performance T-shirts, corporate uniform T-shirts, or premium lifestyle pieces where the garment should not deform after washing.
  • Weight range: Interlock typically runs heavier than single jersey at the same yarn count. Brands targeting a premium hand feel often specify interlock when they want a fabric that feels substantive without relying on higher GSM single jersey.
  • Sewing implications: The firmer structure of interlock can slow sewing cycle times on curved seams and may require needle gauge adjustments at your factory. Confirm your OEM partner has consistent interlock sewing experience if this is your chosen construction.

Interlock is better suited to: premium lifestyle T-shirts, corporate uniform pieces, children's T-shirts requiring dimensional stability through repeated washing, and any application where a firmer, more structured hand feel justifies the added cost.

Construction Comparison at a Glance

The table below summarises the key production differences between the two constructions. Use it as a starting point when briefing your factory or filling in your tech pack construction field.

CharacteristicSingle JerseyInterlockBrand Implication
Needle bedsOneTwoInterlock costs more to knit
Edge behaviourCurls at raw edgesStable, no curlInterlock simplifies finishing
Surface textureSmooth face / textured backSmooth on both sidesBoth print well; jersey more common for DTG
Lateral stretchHigherLowerJersey for relaxed fit; interlock for structured fit
Shape retention after washModerateHigherInterlock preferred for uniform or premium applications
Typical GSM range120–220 GSM (typically)150–300 GSM (typically)Interlock skews heavier
Relative cost per metreLowerHigherJersey more cost-efficient at scale

GSM figures are directional; confirm with your factory based on yarn count and machine gauge. Final GSM should be locked in your tech pack before sampling.

Cotton, Polyester and Blends: How Fibre Choice Affects Bulk Order Results

Once construction is decided, the next variable is fibre content. For T-shirt OEM orders, the relevant choices reduce to three practical categories: 100% cotton, 100% polyester, and cotton-polyester blends (with or without a third fibre such as viscose or elastane). Each behaves differently in dyeing, large-order washing tests, and decoration processes.

100% Cotton

Cotton remains the most widely specified fibre for consumer-facing T-shirt brands, particularly those targeting lifestyle, streetwear, and premium casual markets. The reasons are partly functional and partly commercial: cotton accepts reactive dye well, produces a deep, accurate colour on DTG printing, and carries strong consumer perception of quality and comfort.

From a bulk production standpoint, however, 100% cotton introduces the most significant shrinkage risk of any T-shirt fibre choice. Cotton fibres absorb moisture and swell during washing, causing the fabric to contract — a behaviour known as hygral relaxation shrinkage. Without pre-treatment (pre-shrinking or sanforisation), cotton single jersey can shrink in the length and width after the first wash, shifting finished garment measurements outside your approved size tolerance.

Several points matter here for bulk orders:

  • Ring-spun vs open-end cotton: Ring-spun cotton uses longer fibres twisted tightly, producing a smoother, stronger yarn that holds its shape better and pills less in repeated washing. Open-end (rotor-spun) cotton is faster and cheaper to produce but creates a coarser, weaker yarn more prone to pilling and colour fading. For branded T-shirts intended for retail or direct-to-consumer sale, ring-spun cotton is the production standard; open-end is generally appropriate only for high-volume promotional or event-use garments.
  • Combed cotton: Combing removes short fibres and impurities before spinning, producing an even finer, smoother yarn than standard ring-spun. Combed ring-spun cotton is the premium specification for T-shirts where surface smoothness matters for high-resolution DTG printing or for brands positioning above the mass market.
  • Pre-shrinkage requirements: Brands should specify pre-shrinkage treatment (sanforisation or compaction finishing) in their tech pack. Without this specification, your factory may not apply the treatment, and your finished garments may not hold stated measurements post-wash. This is one of the most common sources of customer complaints on cotton T-shirt orders.

For brands ordering graphic or lifestyle T-shirts, fabric performance should be evaluated alongside shrinkage control and print requirements. Industry resources such as CottonWorks fibre and fabric performance resources can provide additional technical background when comparing cotton specifications. 100% ring-spun cotton single jersey with specified pre-shrinkage treatment is typically the preferred starting point for many branded T-shirt programs.

100% Polyester

Polyester is the standard fibre for performance T-shirts, sportswear, and sublimation-printed garments. As a synthetic fibre, polyester absorbs very little moisture, which means it dries quickly — a functional advantage for activewear and a practical one for production, since polyester garments move through finishing processes faster than cotton equivalents.

The more important characteristic for most OEM brands, however, is polyester's relationship with sublimation printing. Sublimation dye bonds specifically to synthetic polymer chains — and does not bond to natural fibres. On a 100% polyester blank, sublimation produces vivid, full-colour prints that are embedded in the fabric rather than sitting on the surface. On a 50/50 cotton-polyester blend, sublimation only bonds to the polyester portion, resulting in prints that appear washed out, pale, or dull — a problem that is invisible at the initial sampling stage if the sample is viewed next to the digital proof rather than against a consistent colour standard.

Additional polyester production considerations:

  • Dye sublimation vs reactive dye: Polyester requires disperse dye (for piece dyeing) rather than reactive dye used for cotton. If your factory primarily runs cotton, confirm they have the appropriate dye system for polyester before placing an order. Dyeing cotton and polyester in the same facility without segregated dye systems can cause cross-contamination.
  • Pilling behaviour: Lower-quality polyester yarns can pill more than cotton in repeated abrasion. For T-shirts worn against the body, specify anti-pilling polyester or confirm the factory is sourcing from an appropriate yarn tier.
  • Shrinkage: 100% polyester shrinks significantly less than cotton under normal wash conditions. This is an advantage for maintaining size consistency across a large order but can become a disadvantage if your brand transitions between fabric types in different seasons, since size callouts designed for cotton may not carry across to polyester without a revised size set.

For activewear and sublimation-print T-shirts: 100% polyester is the correct fibre specification. If your range mixes sublimation-printed and non-printed styles, your factory needs to manage these as separate fabric streams — confirm this capability before ordering.

Cotton-Polyester Blends: The Practical Default for Most Brand Orders

Cotton-polyester blends occupy the middle ground that most branded casual T-shirt collections settle on: the feel and print compatibility of cotton, with the dimensional stability and wash durability of polyester. The two most common ratios in bulk production are:

  • CVC (Chief Value Cotton): Cotton-dominant blend, typically 60% cotton / 40% polyester, or similar ratios where cotton exceeds 50%. CVC blends behave more like cotton in terms of hand feel and DTG print compatibility, while the polyester component reduces shrinkage and improves colour retention over wash cycles. This is a common default for lifestyle and streetwear brands.
  • 50/50 blend: Equal parts cotton and polyester. More resistant to shrinkage than CVC, with slightly better moisture-wicking than pure cotton. The trade-off is a slightly synthetic hand feel at lower GSM and reduced DTG print vibrancy compared to high-cotton specs. More commonly used for corporate and promotional T-shirts where durability and shrink resistance matter more than premium feel.

Tri-blends (cotton/polyester/rayon or viscose) add a third fibre to improve drape and softness. Viscose or rayon introduces a more fluid, drapey handle that many contemporary lifestyle brands find attractive. The production consideration: rayon is less stable during wet processing than cotton or polyester, and tri-blend fabrics can show more variation in finished measurements batch-to-batch. For brands requiring tight size consistency across large orders, tri-blends require additional tolerance checks during bulk production.

Fibre Comparison for Bulk T-Shirt Orders

The table below provides a direct comparison across the three fibre categories most relevant to T-shirt OEM decisions. Performance indicators are directional — confirm specific parameters with your factory or request fabric certification data during sampling.

Factor100% CottonCotton-Poly BlendCotton-Poly Blend
100% Polyester
Shrinkage riskHigher — pre-shrinkage treatment requiredModerate — lower than pure cottonLow — most stable across wash cycles
DTG print resultBest — high ink absorption, vivid detailGood — slightly reduced vs pure cottonPoor — ink sits on surface, may crack
Screen print resultExcellentExcellentGood (adhesion may vary by ink type)
Sublimation compatibilityNot suitablePartial only — dull result at low poly %Ideal — full colour saturation at 100% poly
Dye system requiredReactive dyeReactive + disperse (complex process)Disperse dye
Colour retention (after 30 washes)Moderate — fades with timeGood — blend improves colour stabilityVery good — polyester holds dye well
Cost at fibre stageHigherModerateLower
Typical brand positioningPremium, lifestyle, streetwearCasual, corporate, mid-marketActivewear, performance, sublimation print

Performance ratings are directional based on standard production conditions. Specific GSM, yarn quality, and finishing treatment all affect final results. Request fabric test reports during sampling for production-critical specifications.

Print Method and Fabric: Aligning Your Decoration Choice Before Sampling

One of the most avoidable delays in T-shirt OEM development is discovering — at the sampling stage — that the selected fabric does not work with the intended decoration method. Fabric and print method are not independent choices. They interact at a physical level, and misalignment between the two results in either aesthetically unacceptable samples or in prints that degrade rapidly after washing.

This section covers the three decoration methods most commonly applied to T-shirts in bulk OEM orders: screen printing, DTG (direct-to-garment), and sublimation. Heat transfer is included briefly as a supplementary method.

Screen Printing

Screen printing deposits ink on the fabric surface through a mesh screen, with a separate screen for each colour. It is the most cost-effective method for high-volume, limited-colour designs — and the method most tolerant of fabric variation. Screen printing works across cotton, polyester, and blended jerseys without significant compatibility issues, provided the ink system matches the fibre type.

The main fabric consideration for screen printing is surface smoothness and stability during printing. Single jersey with a smooth face side prints cleanly. Interlock, with its identical-surface-on-both-sides structure, also prints well. Higher GSM fabrics can absorb more ink, which is relevant for white ink on dark grounds — a specification worth confirming with your factory if your design calls for it.

For polyester and high-polyester blends, your factory should use low-cure or polyester-compatible inks to prevent dye migration — a phenomenon where the disperse dye in polyester bleeds into the screen print ink during curing, discolouring the print. Confirm ink system compatibility if your design uses light colours on a coloured polyester blank.

DTG Printing

DTG printing jets water-based ink directly into the fabric fibres, producing prints that feel soft and integrate with the fabric rather than sitting on top. Print vibrancy and washability are directly tied to cotton content: the higher the cotton percentage, the better the ink absorption and the more accurate the colour reproduction.

For OEM bulk orders using DTG, the fabric specification should reflect this requirement. Key parameters:

  • 100% ring-spun cotton or CVC with at least 50% cotton content produces the most reliable DTG results at scale.
  • Pre-treatment (applying a liquid before printing to fix the ink) is standard for dark-coloured garments and for polyester-containing blends. Whether this is applied by your factory or by a third-party print facility affects your supply chain timeline — clarify this at the RFQ stage.
  • Fabric surface must be smooth and free of raised texture, pilling, or nap. A fabric that has been incorrectly finished or stored can produce uneven ink absorption across a print run.
  • Tri-blend fabrics can produce DTG results with a slightly faded, vintage character due to the drape of the rayon component — this is an intentional aesthetic choice for some brands, not a defect. Confirm the expected result with a physical sample rather than a digital proof.

For brands relying on DTG for bulk fulfilment: specify cotton content minimum in your tech pack as a production requirement, not a preference. DTG print houses will refuse to guarantee results on fabrics below their minimum cotton threshold.

Sublimation Printing

Sublimation is a dye process, not a surface print. Heat converts solid sublimation ink into a gas that bonds with polyester polymer chains within the fabric. Once cooled, the dye is permanently embedded in the fibre — not sitting on the surface. This produces prints that do not crack, peel, or fade with washing, and allows for full-coverage, edge-to-edge pattern design on T-shirts.

The critical fabric requirement is clear: sublimation requires polyester content, and the higher the polyester percentage, the more vibrant and accurate the print. On a 100% polyester blank, sublimation achieves its maximum colour saturation. On a 50/50 blend, only the polyester portion bonds dye — the result is a visibly muted, faded version of the intended design. On 100% cotton, sublimation does not work.

This creates a specific OEM risk: if a brand places a bulk order of mixed-fibre T-shirts for sublimation printing without confirming polyester content with the factory, the entire order may print incorrectly. Brands specifying sublimation-compatible T-shirts should:

  • Confirm minimum 80–100% polyester content in writing before fabric is sourced
  • Request a physical print test on the confirmed bulk fabric before committing to a production run
  • Avoid switching fabric suppliers between sampling and bulk production — the same polyester content from a different yarn supplier can produce slightly different colour outcomes with sublimation dye

Heat Transfer

Heat transfer applies pre-printed designs to fabric using heat and pressure. Unlike sublimation (which bonds dye to the fibre), heat transfer creates a surface layer that adheres to the fabric. The method works across fabric types but produces a slightly tactile, on-surface print feel.

For bulk OEM T-shirt orders, heat transfer is most commonly used for: small runs where screen setup cost is prohibitive; designs with photographic detail that screen printing cannot reproduce accurately; and reflective or metallic finishes. Fabric compatibility is broad — heat transfer works on cotton, polyester, and blends. The key variable is the surface finish of the fabric: textured, brushed, or napped surfaces reduce adhesion quality.

Print Method vs Fabric: Decision Matrix

Decoration MethodRecommended FabricCritical Constraint
Screen printingCotton, cotton-poly blend, or 100% polyester (with polyester ink)Specify anti-migration ink for polyester blanks with light-colour designs
DTG printing100% ring-spun cotton or CVC (min. 50% cotton)Cotton % minimum must be stated in tech pack; pre-treatment method must be confirmed
Sublimation100% polyester (min. 80% poly for acceptable results)Any cotton content degrades print; fabric supplier must not change between sampling and bulk
Heat transferCotton, poly, blends (broad compatibility)Textured or napped surfaces reduce adhesion — confirm with a physical adhesion test

The fabric and decoration method must be confirmed as a pair before bulk fabric is sourced. Changing either variable after sampling may require a new sample round.

Shrinkage in Bulk T-Shirt Orders: What Happens and How to Manage It

Fabric shrinkage is one of the most common sources of disputes between brands and OEM factories on T-shirt orders. A garment can measure correctly at the point of delivery and still fail to meet stated measurements after the brand's first wash test — not because the factory made an error, but because shrinkage was not specified as a performance requirement before bulk production began.

Understanding the mechanics of shrinkage, and how to control it through fabric specification, is a practical production skill for any brand placing bulk T-shirt orders.

Why Cotton Shrinks and Polyester Doesn't

Cotton fibres are hydrophilic — they absorb water readily. When a cotton yarn absorbs moisture, the fibre swells radially and contracts longitudinally. This causes the knitted loops in the fabric to pull tighter, reducing the overall dimensions of the garment. The first wash is the most significant shrinkage event for untreated cotton; subsequent washes produce progressively less contraction.

Polyester fibres are hydrophobic — they resist moisture absorption. Polyester T-shirts retain their dimensions through repeated washing without the hygral relaxation that causes cotton to shrink. This is why polyester and high-polyester blends are the default choice for applications where consistent sizing across the garment's lifespan matters more than the natural feel of cotton.

Pre-Shrinkage Treatments

Two finishing treatments are standard in T-shirt production to reduce cotton shrinkage before the garment reaches the consumer:

  • Sanforisation: A mechanical pre-shrinking process applied to fabric yardage before cutting. The fabric is fed through rollers under controlled compression, relaxing the yarn tension and reducing the potential for post-wash shrinkage. Sanforised cotton typically has lower residual shrinkage than untreated cotton, but the final rate depends on fabric construction, GSM, finishing quality, and the factory's wash-test result.
  • Compaction finishing: A related mechanical process applied after dyeing, which relaxes the fabric structure without the use of heat. Compaction is particularly common in dyehouse finishing lines for jersey fabrics.

Brands should specify which pre-shrinkage treatment applies in their tech pack, and should confirm that the factory has applied it by requesting a wash test report from the sample stage. If no pre-shrinkage requirement is stated, the factory may or may not apply treatment depending on their standard practice — and this ambiguity is where measurement disputes originate.

Shrinkage Tolerances and What to Specify

Industry practice for branded T-shirts typically targets residual shrinkage of 3% or less in both length and width after a standard wash cycle. This figure should be explicitly stated as a performance requirement in your tech pack's fabric specification section — not assumed.

When reviewing samples for bulk approval: wash the sample at least once using the garment's care label instructions and measure the key dimensions (body length, chest width, sleeve length) against the approved size spec before signing off on bulk production. Fabric that meets the visual standard at sample approval can still fail the measurement standard after washing if pre-shrinkage treatment was inadequate or inconsistently applied.

Specific shrinkage rates vary by fabric construction, GSM, fibre content, and finishing treatment — and should be confirmed with your factory's lab rather than estimated from general industry norms.

How to Specify T-Shirt Fabric in Your Tech Pack

The choices described in the preceding sections only have production value if they are correctly communicated to your factory. A tech pack that lists only "cotton jersey" leaves five or six variables unspecified — and each unspecified variable is a decision the factory will make on your behalf, not always in the direction your brand intends.

This section covers what a complete T-shirt fabric specification looks like and where common omissions occur.

The Four Core Specification Fields

  • Construction: State the knit structure explicitly. "Single jersey" or "interlock" are the relevant options for most T-shirt orders. If your design calls for something outside these (slub jersey, French terry, etc.), name it specifically and provide a fabric reference or swatch.
  • Fibre content and ratio: State exact percentages. "Cotton-polyester blend" is not a specification; "60% ring-spun cotton / 40% polyester" is. If your design requires a specific yarn type (combed ring-spun, Pima cotton, recycled polyester), state it here.
  • GSM: State a target GSM and acceptable tolerance range (e.g., 180 GSM ± 10 GSM). Leaving GSM unspecified allows the factory to use whatever weight fabric is available in the required fibre content — which may be significantly lighter or heavier than your brand's intended hand feel.
  • Finishing and pre-treatment requirements: State pre-shrinkage treatment, anti-pilling finish (if applicable), and any surface finishing requirements (brushed, washed, enzyme-treated). This section is frequently omitted by brands and is one of the most common sources of quality disputes on delivered bulk orders.

Decoration Method Alignment

As covered in the previous section, your fabric specification and your decoration method must be confirmed as a pair. Once you have determined your print method, add a note in your tech pack's decoration section that cross-references the fabric specification — for example: "DTG printing. Fabric must meet minimum 50% ring-spun cotton content as specified in fabric section. Factory to confirm pre-treatment method."

This cross-reference makes fabric-print compatibility a shared responsibility and creates a documented audit trail if discrepancies arise during quality inspection.

When to Lock Fabric Specification

Fabric specification should be locked before your first sample is produced, not refined through multiple sampling rounds. Changing fibre content or GSM after a first sample is approved restarts the fabric-related portion of the development cycle — new yarn must be sourced, new fabric must be knitted and finished, and new samples must be produced against the revised specification.

In practice, brands often approach fabric selection iteratively, using first samples to feel the hand of a fabric before committing to a spec. This is reasonable for a first collection. For repeat or seasonal orders, the factory should carry your confirmed fabric specification on file, allowing bulk orders to proceed without re-opening the fabric selection process.

Runtang's production team reviews fabric specifications alongside tech packs before sampling begins — brands can request a sample to confirm fabric choice before committing to a bulk order.

Common Tech Pack Fabric Omissions (and Their Consequences)

OmissionWhat the Factory DecidesLikely Consequence
No GSM specifiedFactory selects lowest-cost available weight in the fibreGarment hand feel is lighter than brand expects; customer returns or brand complaints post-delivery
Fibre ratio stated as range, not fixed percentageFactory uses whichever ratio is currently in stockPrint results and shrinkage behaviour vary between production runs
Pre-shrinkage treatment not statedFactory applies (or does not apply) per standard practiceGarment shrinks outside size tolerance after first consumer wash
Decoration method not cross-referenced in fabric specFactory selects fabric independently of print methodSublimation on cotton-heavy blend produces incorrect colour; DTG on polyester-heavy fabric produces poor ink absorption
Yarn type not specified (ring-spun vs open-end)Factory uses lowest-cost yarn available in stated fibreSurface texture, pilling resistance, and print quality fall below brand standard

Incomplete tech pack specifications are one of the most common causes of sampling revision rounds. Each revision round adds lead time and potentially cost. A complete fabric specification on the first brief reduces both.

FAQ

What is the difference between jersey and interlock fabric for T-shirts?

Jersey (specifically single jersey) is knitted on one needle bed, producing a fabric with a smooth front face and textured back, with inherent edge curl. Interlock uses two needle beds, creating a thicker, dimensionally stable fabric that looks and feels the same on both sides and does not curl at edges. For most T-shirt bulk orders — casual, graphic, lifestyle — single jersey is the standard construction. Interlock is better suited to premium or structured applications where shape retention across repeated washing is a priority.

Does 100% cotton or a cotton-polyester blend shrink more in bulk production?

100% cotton shrinks more than cotton-polyester blends under standard wash conditions, particularly in the first wash cycle. The polyester component in blended fabrics resists moisture absorption, stabilising the fabric structure and reducing dimensional change post-wash. Both cotton and blended fabrics can be treated with mechanical pre-shrinkage finishing (sanforisation) to reduce residual shrinkage before the garment reaches the consumer. Brands should specify pre-shrinkage requirements explicitly in their tech pack — this is not a default treatment in all factories.

Which T-shirt fabric works best with screen printing or DTG?

Screen printing works well across cotton, cotton-polyester blends, and polyester, making it the most fabric-tolerant decoration method. For polyester blanks with light-colour designs, specify anti-dye-migration ink to prevent bleed-through during curing. DTG printing produces its best results on high-cotton fabrics — 100% ring-spun cotton or CVC blends with at least 50% cotton. Polyester-heavy fabrics produce noticeably poorer DTG results due to reduced ink absorption. Confirm your fabric's cotton content as a minimum specification in your tech pack if DTG is your primary decoration method.

Can I switch fabric suppliers between sampling and bulk production?

Changing fabric suppliers between approved samples and bulk production introduces consistency risk — particularly for colour (dye batch variation), GSM (weight differences between mills), and print behaviour (especially sublimation, where polyester content and dye affinity vary by yarn source). For brands where colour consistency and print quality are core to the product, the factory should source bulk fabric from the same mill that supplied the approved sample fabric. Confirm this requirement in writing before bulk fabric is ordered.

What is the minimum information I need to specify in a T-shirt fabric brief?

At minimum, your fabric brief should state: construction (single jersey or interlock), fibre content and ratio (e.g., 95% ring-spun cotton / 5% elastane), target GSM with tolerance (e.g., 180 GSM ± 10 GSM), and any pre-treatment or finishing requirements (e.g., sanforised, enzyme washed). For graphic T-shirts, also cross-reference the decoration method to confirm fabric-print compatibility. These four to five data points cover the most common sources of specification disputes and sampling revision rounds.

Build Your T-Shirt Collection with the Right Fabric from Day One

Fabric specification is one of those decisions that looks straightforward at the brief stage and costly at the bulk stage if it has been made without full information. Jersey or interlock, cotton or blend, DTG or sublimation — each pairing has production consequences that show up in sampling rounds, shrinkage tests, and delivered garment quality.

Runtang's production team works with apparel brands at the fabric selection stage — before sampling begins — to confirm that construction, fibre content, GSM, and decoration method are aligned as a set. If you have a design in development or are planning a T-shirt range, share your design or tech pack and our team will advise on fabric specification from a production standpoint. MOQ from 100 pieces per style.

Not sure where to start on the fabric brief? We can walk you through the specification process before your first sample request — no commitment needed.

Related Articles