Introduction to Textile Fabric Part 4: More Double Knit Structures Dr. Jimmy Lam Institute of Textiles & Clothing The Hong Kong Polytechnic University Content • • • • • • Half Milano and Full Milano Rib. Half cardigan and full cardigan Interlock fabric Eight lock and 12-lcok Ponte de Roma Single Pique 1 Milano Ribs Half Milano • There are two types of milano ribs, namely half milano and full milano. Half Milano is two courses per repeat, with first course knits on all needles (front and back) and the second course on front needles only. • Milano Ribs Half Milano • • • Half milano is made up of 1 rib course and 1 plain course; with plain course always on the face side of the fabric. The resultant fabric is an unbalanced structure, with different appearance on both sides. Half milano is seldom knitted as piece goods, it is used for sweaters of coarser gauge (5 to 7 gauge V-bed machine with woollen or acrylic yarns) 2 Milano Ribs Full Milano • • Full milano has three courses per repeat; with one course of 1x1 rib; one course of plain on one side of fabric and another course of plain on the other side. Although full milano is slightly modified from half milano, the fabric property is entirely different Milano Ribs Full Milano • • • • Full milano is normally knitted in higher density to give a firm fabric. The two plain courses of full milano reduces most of the width way elasticity. As a result, full milano is a fabric with much better dimensional stability. Full milano is produced mainly on medium gauge machines as piece goods for suiting fabrics 3 Cardigans (Half Cardigan) • The cardigans are the rib structures with tuck loops. • The first type is the half cardigan or royal rib. This is a 2 courses per repeat, with one course of 1x1 rib and the other course of all needles knit one side and all needles tuck of the other side of the fabric. Half Cardigan • Half cardigan is a wide fabric, the large amount of tuck loops reduce the side way contraction. • If a 1x1 rib shrinks for 30% after relaxation on its width, then the half cardigan will shrink only about 8%. • The structure is mainly produced on coarse gauge V-bed machines for fully fashion or cut and sewn pullovers or cardigans. • Half cardigan is not a balanced structure; the number of courses per inch is different on both sides of the fabric. 4 Full Cardigan (Polka Rib) • Full cardigan has the same appearance on both sides of the fabric (half cardigan has different appearance on both sides) • Although full cardigan is also two courses per repeat, it contains no rib course. • The structure has 50% tuck loops and 50% knit loops. Full Cardigan (Polka Rib) • The excessive tuck loops make the fabric bulk and heavy, therefore the structure is suitable for chunky knitwear. • Full cardigan is normally knitted on 3-12 gauge V-bed machines with wool or acrylic yarns, 5 Interlock Category • There are TWO type of needle arrangement in circular machine. • When the needle heads are offset with each other, it is called rib gating e.g 1x1 rib, 2x2 rib. • If the needle heads are facing with each other, it is called interlock gating, eg. Interlock fabric Interlock fabric • . 6 Interlock fabric • Although interlock is derived from 1x1 rib structure, the fabric properties are not the same. • Differences: – – – – It takes two knitting courses to form one repeat. Much higher in stitch density Lower in widthwise elasticity Fine and smooth surface texture • Similar: – Perfectly balanced structure – Same appearance o both sides – Can only be unroved from the last course. Interlock fabric • Interlock fabrics are mainly produced on specially designed circular double jersey machines called interlock machines. • They are high speed, multi-feeders with closed cam track machines. • The common gauges for interlock fabrics are 2024 npi, using 1/30 Ne cotton or 1/48 Nm worsted yarns. • Worsted interlock is for ladies’ winter suiting fabrics. For those 28 gauge fabrics, the yarns used are mainly texturised polyester of 75 denier. 7 Modified Interlock eight-lock & 12-lock • Both are modified from simple interlock fabric • The fabric is called 8-lock because it takes eight needles to make one repeat of structure; and so is the 12-lock. • Both of these structures are not popular because of the fabric performance is not as good as plain interlock. Pont de Roma • This is a 4 courses per repeat interlock type structure. • It is composed of one interlock course and one tubular course. • A plain interlock fabric has a smooth surface on both side; but when a tubular course is added, the fabric properties changes accordingly. 8 Pont de Roma • The tubular course reduces the widthwise elasticity. • The fabric has better dimensional stability than interlock Discussion • What is Interlock fabric? • What is the different between interlock and rib fabric? 9