Fashion Designer Textile Science & Fiber Properties 1 — Questions and Answers
Question 1: What is the difference between a 'natural fiber' and a 'synthetic fiber' in textile science?
- Natural fibers are always more expensive; synthetic fibers are always lower quality
- Natural fibers originate from plant, animal, or mineral sources; synthetic fibers are manufactured through chemical processes from petroleum or other chemical feedstocks (Correct answer)
- Natural fibers cannot be dyed; synthetic fibers accept all dye types
- Natural fibers are only used in luxury fashion; synthetic fibers in workwear
Correct answer: Natural fibers originate from plant, animal, or mineral sources; synthetic fibers are manufactured through chemical processes from petroleum or other chemical feedstocks
Natural fibers (cotton, wool, silk, linen) come from biological sources. Synthetic fibers (polyester, nylon, acrylic, spandex) are manufactured through chemical synthesis, typically from petroleum derivatives.
Natural fibers subdivide into: cellulosic (cotton, linen, hemp from plant cellulose), protein (wool, silk, alpaca from animal protein), and mineral (historically asbestos, now rarely used). Synthetic fibers include polyester, nylon (polyamide), acrylic, and elastane/spandex. Semi-synthetic or regenerated fibers (viscose/rayon, lyocell/Tencel, modal) occupy a middle category: they use natural cellulose (wood pulp) dissolved and re-extruded as fiber through chemical processes.
Question 2: What is the 'hand' of a fabric and how do designers evaluate it?
- The direction in which fabric is cut
- The tactile characteristics of a fabric: its softness, stiffness, smoothness, drape, and texture as assessed by physical handling (Correct answer)
- The measurement of fabric width
- The brand's logo or label on a garment
Correct answer: The tactile characteristics of a fabric: its softness, stiffness, smoothness, drape, and texture as assessed by physical handling
The 'hand' (or 'handle') is the collective tactile impression a fabric creates when physically handled: its softness or stiffness, smoothness or roughness, warmth or coolness, fluidity or body.
Evaluating hand is an experiential skill developed through extensive fabric handling. Key hand attributes include: drape (how fabric falls and flows), body (stiffness or weight), softness (surface smoothness against skin), resilience (whether it recovers after creasing), and warmth or coolness (thermal conductivity). Fabric buyers and designers handle hundreds of fabrics to develop refined hand assessment skills.
Question 3: What is 'warp' and 'weft' in woven fabric construction?
- Warp and weft are two names for the same yarn system in knit fabrics
- Warp refers to the lengthwise yarns running parallel to the selvedge; weft refers to the crosswise yarns that interlace through the warp in weaving (Correct answer)
- Warp is the technical term for bias-cut fabric; weft for straight-grain fabric
- Warp describes tight weaves; weft describes loose weaves
Correct answer: Warp refers to the lengthwise yarns running parallel to the selvedge; weft refers to the crosswise yarns that interlace through the warp in weaving
In woven fabric construction, warp yarns are the lengthwise threads held under tension on the loom, and weft yarns are woven crosswise through the warp to create interlaced fabric structure.
The warp and weft distinction has critical practical implications. Warp yarns are generally stronger (they must withstand loom tension), so woven fabrics have greatest strength in the lengthwise direction. Pattern making uses grain line arrows to specify that the warp should run vertically for most garment pieces, ensuring the garment hangs correctly and resists stretching with wear. The selvedge (finished edge of woven fabric) runs parallel to the warp.
Question 4: What distinguishes a 'twill weave' from a 'plain weave' and what fabrics result from each?
- There is no difference: all woven fabrics use the same interlacing pattern
- Plain weave interlaces warp and weft over and under alternately (checkerboard), creating cotton muslin and linen; twill weave creates diagonal lines by offsetting interlacing, producing denim and gabardine (Correct answer)
- Twill weave uses finer yarns than plain weave
- Plain weave is only used for silk fabrics; twill for cotton
Correct answer: Plain weave interlaces warp and weft over and under alternately (checkerboard), creating cotton muslin and linen; twill weave creates diagonal lines by offsetting interlacing, producing denim and gabardine
Plain weave (over-one-under-one) is the simplest, most stable structure producing tightly interlaced fabrics. Twill weave offsets the interlacing pattern to create visible diagonal lines, producing softer, more drapeable fabrics with diagonal texture.
Weave structures fundamentally determine fabric characteristics. Plain weave fabrics (muslin, taffeta, organza, broadcloth) are firm and crisp due to maximum interlacing points. Twill weave fabrics (denim, gabardine, herringbone, tweed) have fewer interlacing points creating diagonal surface ridges: they are softer, more drapeable, and more wrinkle-resistant. Satin weave (a third major category) minimizes interlacing points to create a smooth, lustrous surface (satin, sateen, charmeuse).
Question 5: What is 'GSM' in textile specification and why does it matter in fashion design?
- Garment Seam Measurement: the standard for seam allowance
- Grams per square meter: the weight of fabric, which determines its drape, warmth, durability, and appropriate application in garment design (Correct answer)
- Global Sizing Method: an international garment sizing standard
- Greige Stock Management: a fabric inventory system
Correct answer: Grams per square meter: the weight of fabric, which determines its drape, warmth, durability, and appropriate application in garment design
GSM (grams per square meter) is the standard measurement of fabric weight. It directly affects a fabric's drape, warmth, structure, and appropriate use: a 120 GSM cotton works for summer shirts; a 400 GSM wool is appropriate for winter coats.
Typical GSM ranges by application: lightweight fabrics (30 to 150 GSM) include voile, chiffon, and lightweight jersey for blouses and dresses; medium weight (150 to 350 GSM) covers shirting, dress fabrics, and denim; heavy weight (350+ GSM) is appropriate for outerwear and technical applications. Designers specify GSM in tech packs to ensure factories source fabric within the intended weight range. A 10 percent deviation in GSM can noticeably change how a garment hangs and performs.
Question 6: What property of spandex (elastane/Lycra) makes it essential in modern activewear and stretch fashion?
- It has the highest moisture absorption of any synthetic fiber
- It can stretch to 4 to 7 times its original length and recover to its original dimensions without permanent deformation (Correct answer)
- It provides exceptional UV protection in outdoor garments
- It is the most environmentally sustainable synthetic fiber
Correct answer: It can stretch to 4 to 7 times its original length and recover to its original dimensions without permanent deformation
Spandex/elastane is a segmented polyurethane fiber with exceptional stretch-and-recovery properties: it can elongate to 4 to 7 times its length and return to original dimensions, enabling garments to maintain shape through repeated stretching.
Spandex (DuPont trademark Lycra) revolutionized activewear, swimwear, foundation garments, and denim when it was introduced commercially in 1962. Even small percentages (2 to 5 percent) in a fabric blend add significant stretch-and-recovery. Spandex is never used alone: always blended with other fibers. It has poor heat resistance, can be damaged by chlorine, and requires careful laundering. Modern bi-stretch fabrics (stretching in both warp and weft directions) typically use 5 to 10 percent spandex in both directions.
Fashion Designer Textile Science & Fiber Properties 1
What is the difference between a 'natural fiber' and a 'synthetic fiber' in textile science?