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The inspection of fabric appearance provides a relatively detailed overview of the knowledge related to assessing the visual quality of textile fabrics, covering aspects such as identifying the front and back sides, distinguishing between straight and twisted fibers, detecting defects, identifying weft skewness, and correcting it. Next, Baijian Testing will provide you with a detailed explanation, in the hope of helping you. I. Identification of the front and back sides: Among various textile fabrics, some are difficult to distinguish between their front and back sides. Slight carelessness during garment sewing can lead to mistakes, such as uneven color distribution or inconsistent patterns; in severe cases, this can result in obvious color differences, blurred pattern designs, and the fabric being turned upside down, all of which affect the appearance of the finished garment. In addition to using visual and tactile methods to determine the front and back sides of a fabric, it can also be identified by examining the structural characteristics of the fabric, its pattern features, any special visual effects resulting from special treatment, as well as the labels and stamps attached to the fabric. 1. Identification based on the fabric’s structure: (l) Plain weave fabrics: It is difficult to distinguish the front and back sides of fabrics with a plain weave structure; therefore, in practice there is no distinction between them (except for printed fabrics). Generally, the front side of plain weave fabrics is relatively smooth and flat, with a uniform and vivid color. (2) Twill fabrics: Twill weaves are divided into single-faced twill and double-faced twill. The pattern of single-faced twill is clear and distinct on the front side, while it is blurred on the back side. Furthermore, in terms of the inclination of the patterns, the patterns on the front side of single-yarn fabrics slope from the top left to the bottom right, while those on half-woven or full-woven fabrics slope from the bottom left to the top right. The patterns on the front and back sides of double-faced twill fabrics are essentially the same, but in opposite directions. (3) Satin fabrics: Since the warp or weft threads on the surface side of satin fabrics protrude significantly, the fabric surface is smooth and tight, giving it a glossy appearance. The pattern on the reverse side resembles both plain weave and twill weave, with a relatively dull luster. Furthermore, warp twill and warp satin on the front side have more warp floats, while weft twill and weft satin on the front side have more weft floats. 2. Identification based on fabric patterns and colors: The patterns and designs on the front side of various fabrics are clear and distinct, with well-defined shapes and sharp line contours; the colors are vivid and rich. On the back side, however, the colors are lighter, the line contours are blurrier, the patterns lack depth, and the luster is weaker. 3. Based on changes in fabric structure and pattern recognition, jacquard, tartan, and stripe fabrics exhibit a wide variety of patterns and textures. On the front side of the weave, there is generally less floating yarn, and stripes, patterns, and other designs are more visible than on the back side. The lines are clear, the contours are distinct, the color is uniform, and the luster is bright and soft. On the back side, however, the patterns appear blurred, the contours are not clear, and the color is dull. There are also some woven fabrics whose patterns on the reverse side are unique and distinctive, with harmonious and soothing colors; therefore, the reverse side is used as the main material in garment manufacturing. As long as the fabric’s yarn structure is proper, the length of the floating yarns is uniform, and it does not affect the durability of the fabric, the reverse side can also be used as the front side. 4. Identification based on the fabric edge: Generally, the edge of a woven fabric is smoother and firmer on the front side than on the back side, while the edge on the back side curls inwards. Fabrics woven on shuttleless looms have relatively smooth edges on the front side, while on the back side, tufts of weft yarn ends can be easily found along the edges. There are some high-quality fabrics. Such as velvet, where numbers or other text are woven along the edges of the fabric; the numbers or text on the front side are clearer, more visible, and smoother ； The characters or text on the reverse side are rather blurry, with the font appearing reversed. 5. Identification based on the visual effects resulting from special finishing of fabrics: (1) Flocked fabrics: The front side of the fabric has dense, raised fluff, while the back side has a fluff-free texture. The surface texture is distinct, such as plush, velvet, velour, corduroy, etc. Some fabrics have such dense fluff that it’s difficult to even see the weave pattern of the ground fabric. (2) Embossed fabric: After chemical treatment, the patterns on such fabrics have clear front-side contours, a layered structure, and vivid colors; in the case of velvet-type embossed fabrics, the velvet surface is full and even, as seen in fabrics like embossed silk and corduroy. 6. Identification by trademark and seal: During the inspection of each piece of fabric before it leaves the factory, product trademark labels or instructions are usually attached, with the side where they are attached being the reverse side of the fabric; the side of each piece of fabric that has the date of manufacture and inspection seal at both ends is also the reverse side. Unlike domestic products, the trademark label and stamp on export products are applied to the front side. II. Identification by the direction of the fluff: Some clothing fabrics, such as corduroy, velour, velvet, floss, and various types of woolen fabrics, have a fluff structure with a distinct direction. There is a significant difference in the fluff on the front and back sides of these fabrics. It is generally touched by hand; hair that stands upright is called reverse hair. Hair that is easily tamed is called tame hair. Furthermore, there are also significant differences in color. When using such fabrics to make clothing, it is easy to tell which side of the velvet is the front side; for example, the velvety side of corduroy is the front side. To determine the direction of the fabric’s fibers correctly, one must cut the fabric with the fibers facing either outward or inward. Furthermore, when cutting with fabric featuring directional fibers, the single-piece cutting method must be used to ensure that the fibers on the main and secondary parts are aligned in the same direction; otherwise, the appearance of the finished garment will be inconsistent. Some fabrics have a shimmering effect, and it is also necessary to pay attention to the direction in which they are laid; otherwise, the color of the shimmer will be inconsistent, affecting its appearance. For fabrics with asymmetrical grids, it is also necessary to pay attention to the direction of the pattern; the handling method is the same as that used for woolen and corduroy materials with a defined direction. III. Defect Identification: The presence or absence of defects is an important criterion for assessing the quality of fabric. The main causes of defects include the following: 1. Defects resulting from poor fiber quality, known as yarn defects; 2. Defects that occur during weaving, known as weaving defects; 3. Defects that arise during processes such as printing and finishing, known as printing and finishing defects. Severe defects should be cut out; for lighter defects in woolen and silk fabrics, a small thread should be tied to the edge of the fabric outside the defect as a marker, which is commonly known as a \"little tail\". On other textiles, such as rayon and polyester-cotton blends, no \"tassels\" are used; instead, the grade of the fabric is determined based on specific conditions (the severity of defects). Minor defects can directly affect the appearance, while severe defects can reduce the local strength and wear resistance of the fabric; therefore, defects on the fabric should be avoided as much as possible during cutting. If avoidance is not possible, the defect can be placed in areas of the garment that are not frequently worn, so as not to affect its appearance or durability. 1. Original yarn defects. Defects on the fabric caused by yarn defects. 2. Defects in primary-color fabric. 3. Defects in colored woven fabrics. 4. Defects in printed and dyed fabrics. IV. Identification and Correction of Weft Misalignment: During the weaving and finishing processes of various colored woven fabrics, mechanical tension and other factors can cause the weft threads to be misaligned across the fabric surface; this phenomenon is collectively referred to as “weft misalignment”. Weft slant includes checked slant, patterned slant, and weft yarn slant, among which checked slant is the most common, especially in various types of checked velvet fabrics. There are three forms of weft skew in colored woven fabrics: 1. One-sided weft skew: This results in the fabric’s surface having a sloped shape with one end being higher than the other. 2. Median arcuate weft skew: characterized by a circularly shaped indentation in the middle of the fabric’s surface. 3. Lateral arcuate weft skew: It is characterized by an arc-shaped indentation on one side of the fabric’s width (the left or right side). Regardless of the type of skew, if it is not corrected in advance, it will impair both the appearance and the quality of the garment once it is cut into clothing. Severe weft skew on patterns or striped fabrics can cause the stripes and patterns to not align with each other on the left and right or front and back of the garment pieces, significantly affecting the appearance quality of the clothing. Failing to correct the weft skew can result in uneven weft threads in the fabric pieces, causing the finished garment to twist and not lie flat, which leads to serious internal quality issues in the garment. There are two methods for correcting weft skew: 1. Manual correction: Wet the raw material with water and then pull it in the direction of the weft skew by two people. Although this method is effective, it requires a high level of labor intensity and is slow. 2. Machine correction: Weft skew correction machines are mostly designed and manufactured by clothing factories themselves. The straightening machine consists of five main components: a frame, a transmission system, a steam spraying device, an adjusting loom tensioning device, and an ironing roller. Its advantages are reduced effort and fast work efficiency. For fabrics with severe skew, it requires repeated corrections to achieve the desired result. The Baijian Platform (https://www.objpt.com) is committed to providing convenient and efficient testing services for enterprises and individuals. Simplify the testing process and improve the efficiency of testing services; by leveraging the Internet plus testing e-commerce, diverse options can be provided to customers. This approach helps to reduce testing costs and increase efficiency, breaking through industry limitations and bottlenecks to create a new platform for innovation in this sector. We provide you with the highest quality, most convenient, and most professional testing services.