ITC3009 Product Quality and Evaluation Student: Kong Ka Yu Kate ID: 11301265D Lesson 5 Fabric Properties Homework 1. A 2. A 3.
A 4. E 5. List some important physical properties of the fabric. The properties of textile fabrics are important for the control of quality, as well as for end use determination.
There are several physical properties of fabric which affecting the performance and aesthetic of fabric. The first one is fabric count, it influences thickness of the fabric. It is the number of ends or picks per inch for woven fabrics, or the number of wales or courses per inch for knit fabrics.Variation occurs because of the weaving or knitting process and from finishing processes.
Usually the higher the fabric count, the better the quality and the higher the cost. The second is fabric unit weight. It is the mass per unit area. It is expressed in one three ways; ounces per square yard, ounces per linear yard, and linear yards per pound.
It is significant in determining both end use and quality. Moreover, it is fabric width. It means the distance from one edge to the other. Measurement is made perpendicular to the fabric edge, usually including the selvage area.The width is expressed in inches and is usually an average number of measurements taken at evenly spaced interval along the fabric pieces. Next one is fabric shrinkage.
It is the process in which a fabric becomes smaller than its original size, usually through the process of laundry. It is undesirable property to the apparels. So the material has to be either shrink resistant or shrink recoverable, such as anti-shrink finish is to keep the fabric smooth and free from undesirable shrinkage. The last one is fabric thickness.It is the distance between the upper and lower surfaces of the material.
It is measure under a specific pressure. Warmth and bulk properties depend on the fabric thickness- to-weight ratio. It can also be used as a performance indication of abrasion resistance or shrinkage tests. Generally speaking, the thicker the fabric is, the more comfortable in wearing. 6.
What is the commonly used fabric inspection system? Mainly, two industry methods used are the Ten point and Four point systems. The most commonly used is four-point system.A minimum of 10% inspection of fabrics is required. The four-point system derives its name from the basic grading rules that a maximum of four penalty points can be assessed for any single defect. Normally, we inspect 10% of the rolls we receive and evaluate them based on this system.
This way, we can avoid fabric related quality problems before it is put into production The following table shows the point system. Size of Defect| Penalty Points| Length of defects in fabric (either length or width)| Defects up to 3 inches| 1|Defects > 3 inches < 6 inches| 2| Defects > 6 inches < 9 inches| 3| Defects > 9 inches| 4| Holes and openings(largest dimension)| 1 inch or less| 2| Over 1 inch| 4| After inspection, the inspector will add up the defects points and then use the following formula to determine the rate of points per 100 yards. There are some common fabric faults, such as bow, skew, hole, mispick etc. Fabric checker should know common defects found in fabrics and he must recognize defects on the fabric at the time of fabric inspection.For the acceptance criteria and calculation, 40 points per 100 yards is the acceptable defect rate.
The ten point system for piece goods evaluation was approved by the Textile distributors institute and the National Federation of Textile, in 1955. It is designed to identify defects and to assign each defect a value based on severity of defect. The system assigns penalty points to each defect depending on its length and whether it is in the warp (ends) or weft (fill) direction. The following table shows the point system. Warp defects| Points| Weft defects| Points|Under 1”| 1| Under 1”| 1| 1”-5”| 3| 1”-5”| 3| 5”-10”| 5| 5”-1/2 width of goods| 5| 10-36”| 10| Over 1/2 the width of goods| 10| According to this system, if any defect was found on a finished garment the garment would then be termed a second.
The advantages of it is that in it length of fabric is used and along the length of warp and weft defects are identified. However, there are width limitation behind this system and it is difficult in practical use because point-per-length vary for warp and filling defects. References (2011). Retrieved March 11, 2013 from http://zh. cribd.
com/doc/23645839/4-POINT-SYSTEM (2011). Retrieved March 11, 2013 from http://www. fibre2fashion. com/industry-article/38/3771/development-of-antishrink-treatment-on-cellulosic-knits-part--21. asp (2011).
Retrieved March 11, 2013 from http://wiki. answers. com/Q/What_is_10_point_system_in_fabric_inspection (2011). Retrieved March 11, 2013 from http://www. onlineclothingstudy.
com/2012/08/how-to-use-4-point-system-in-fabric. html Joseph J, Pizzuto (1998). Fabric Science. :, Daniel Powderly (2000) Fabric Inspection & Grading
