Document 6460860

Hosiery technology
Radko Kovar, Irena Lenfeldova,
Martina Syrovatkova
KTT,
Technical University of Liberec,
Halkova 6, 461 17 Liberec, cz
Introduction:
For centuries, the production of hosiery was the
main concern of the knitting industry. The
prototype machines for warp, circular, flat and
fully-fashioned knitting were all originally
conceived for knitting hosiery.
Nowadays, however, hosiery production is centred
almost exclusively on the use of small-diameter
circular machines. In single cylinder and finegauge hosiery particularly, much of the latest
development is centred in Italy.
Brief content (modules):
1. Principles of hosiery technology
2. Production of stockings and tights (pantyhose)
3. Production of socks and knee socks
4. Single-cylinder machines
5. Double cylinder machines
6. Machines programming
7. Finalization of products
8. Structure and properties of products
9. Supplementary information
1. Principles of hosiery technology:
Content (chapters):
1.1. Classification of hosiery products
1.2. Scheme of hosiery products
1.3. Scheme of hosiery knitting
1.4. Materials used in hosiery products
1.5. Welts
1.6. Shaping of heels and toes
1.7. Shaping of legs
1.8. Used knitted structures and designs
1.9. Closing of toes
1.10. Standardization of hosiery products
1.1. Classification of hosiery products
¾The term “Hosiery products” is used for clothes,
covering manly lower extremities (legs and foots)
¾From the point of view of fabric “fines” there are:
¾Fine products, usually made of multifilament yarns on
knitting machines with 24 – 40 needles per 25.4 mm
(fine women stocking and tights)
¾Course products, usually made of spun yarns on
knitting machines with 5 – 24 needles per 25.4 mm
(socks, knee socks, course pantyhose)
Types of hosiery products:
I. According to Type and Size
¾ Stockings, which are designed to fit the leg up to or above the
knee and may or may not be self-supporting
¾ Tights (panty hose), particularly in fine gauge. They may have a
body section of the same knitted structure and the legs and an
inserted gusset and elastic waist-band. They are usually sewn
together from 2 longer stockings.
¾ Three-quarter Hose. This term was originally applied to hose of
knee length and the definition still holds good although in Boys’
and Girls’ ¾ hose a turnover top is often used. The term ¾ sock is
rarely used now but formerly referred to children’s sock having a
fashioned leg and rib top.
Types of hosiery products:
I. According to Type and Size
¾ Men’s half-hose. This is the trade term for men’s socks. A
distinctive feature is that the upper portion or “top” is of a ribbed
character in order to fit closely to the leg. Usually are in two leglength ranges (7 - 9 and 11 - 15 inches, 18 - 23 and 28 – 38 cm)
¾ Socks. This term is applied to children, women’s and men’s
knitted footwear having a short leg and ribbed top. Long ago it has
also been used for a foot covering with ankle and turnover top.
Presently the inturned top usually makes top of the socks.
¾ Footies. Very short cushioned foot sock. Top reaches to the
anklebone
¾ Footlets. Covers only toe, foot ant heel
¾ Bootees and Infantees. Soft, fluffy knitted foot coverings for
infants. Footwear knitted to the shape of the foot usually in a fancy
rib or purl stitch for children of pre-walking ages
Types of hosiery products:
II. According to Yarns and Gauge
¾ Knitted footwear may be manufactured form all kinds
and counts of yarns but whereas the material is
frequently mentioned the count is rarely stated. An
indication of the relative fineness is given by the gauge,
which is expressed in one of two ways:
¾ Number of wales in hose, i.e., number of needles in machine
¾ Gauge of straight-bar machine on which the hose leg is made
Types of hosiery products:
III. According to Process of Manufacture
¾ Three types of hosiery machines, in order of their
increasing complexity and needle bed arrangement, are:
¾ Single cylinder,
¾ Cylinder and dial (they are often considered as singled
cylinder machines if dial is not able to knit wales of stitches)
¾ Double cylinder
Ladies’ fine-gauge seamless hose and tights are knitted in plain
structure on single-cylinder machines with holding-down
sinkers
Types of hosiery products:
III. According to Process of Manufacture
¾ Ladies’ fine-gauge seamless hose and tights are knitted
in plain structure on single-cylinder machines with
holding-down sinkers.
¾ Men’s, ladies’ and children’s socks and half-hose in rib
or purl (links-links) structure are knitted on doublecylinder machines with reciprocated heel and toe that
has been closed by linking. Can be an anklet as well as
an over-the-calf length. A typical machine specification
would be 4-inch diameter, 168 needles.
Types of hosiery products:
III. According to Process of Manufacture
¾ Sports and casual socks (A broad hosiery term used to
describe all women's socks and any men's socks with the
exception of dress, athletic, and work styles.) in a plain
base structure are now usually knitted on single-cylinder
machines with holding-down sinkers.
¾ More formal simple rib socks may be knitted on
cylinder and dial rib machines termed ‘true-rib’
machines.
Types of hosiery products:
III. According to Process of Manufacture
Other possibilities:
¾ Fully-fashioned, produced on a straight bar frames and shaped by
change of working needles.
¾ Fashioned Seamless, shaped by increasing or decreasing of the
number of wales on a flat or circular machine; in some cases
ordinary seamless hose shaped by gradually reducing the stitch
length have been marked “fashioned”.
¾ Seamless hose are shoes possessing tubular legs and feet and
seamless heel and toe pouches.
¾ Tailored hoses are cut from narrow or wide tubular fabric or warp
knitted fabrics.
Types of hosiery products:
IV. According to Stitch, or Design and Colour
¾ Plain half-hose are those with drop-stitch or accordion
stitch are sometimes used.
¾ Fancy Plated hose – where the pattern or design is obtained
by using two threads, one or other of which appears on the
face.
¾ Plush structures
¾ Laid-in structures (all in different modifications)
¾ Plane double-faced structures
¾ Ribbed hose are usually named after the character of the
rib-stitch used, e.g., 1 x 1 ribbed hose or 2 x 1 ribbed hose
¾ Jacquard Hose – the term jacquard is loosely applied to
mean fancy design in colour
Machines used:
¾Majority of hosiery
products is produced on
small-diameter automatic
circular knitting machines
Machines used:
¾Another used technologies are mainly
¾Warp knitting
¾Weft knitting on flat machines. Example:
1.2. Scheme of hosiery products
¾Majority of hosiery products differs mainly in
product length. The shortest are footlets, the
longest tights (pants).
¾Some products uses only inner part of the long
product (knee-guard etc.)
¾Main types of
hosiery products are:
¾Footlets (covers only
toe, foot ant heel)
¾Socks of different
lengths
¾Half hoses (reach
under or above the
knee)
¾Stockings
¾Tights (usually sewn
from 2 longer
stockings).
1.3. Scheme of hosiery knitting
¾Originally (before and after the second world
war) fine stockings were knitted on straight bar
frames (products with seams).
¾Now great majority of hosiery seamless products
comes from circular knitting machines of small
diameter (mostly between 3.5 and 5.0 “E or 76.2
and 147 mm).
¾Production on flat knitting machines or warp
knitting machines is as well possible.
1.3. Scheme of hosiery knitting
¾Single cylinder machines prevail, although they
are able to create only single side structure and
problems with fast and extensible welt and with
border curling must be solved.
¾Double cylinder machines are able to knit double
side fabric, but several disadvantages cut their
production down. They are not available in fine
gauges.
The scheme of single cylinder machine:
1. Latch knitting
needles in cylinder
bed
2. Sinkers
3. Cylinder cams
4. Sinkers ring cams
More in module 2.
The scheme of double
cylinder machine:
1. Double-sided knitting needles
2. Sinkers
3. Upper cylinder sliders
4. Lower cylinder sliders
Other mechanisms of machines:
Knitting mechanism is completed mainly by:
¾ Yarn supply system (creel, tensioners and
feeders, guides)
¾ Fabric take-of (often combination of
pneumatic and mechanic systems)
¾ Machine drive (to enable reciprocated heel
and toe both rotation and oscillatory
movement of the bed is necessary)
¾ Machine control (computer, control drum…)
¾ Other parts (checking of yarn, needles, fabric,
frame, electrical installation etc.)
1.4. Materials used in hosiery products
¾All usual textile yarns could be used, produced
both from staple and continuous fibers (spun yarns,
monofilament, multifilament)
¾Usually fine hosiery products prefers continuous
fibers and course products staple spun yarns
¾Yarn linear density needs to correspond with the
machine gauge g, usually defined as number of
knitting needles per 25.4 mm (one English inch)
¾Roughly yarn diameter could be somewhere
around l/5 of needle pitch (25.4/g) or lower
Mostly used materials for fine products:
a) Polyamide multifilament
¾ Low extensibility
¾ High extensibility
¾ Wide range of linear density (from 1.5 to 8 tex)
b) Elastomeric materials (polyurethane), usually
only 3 – 12 % of product mass
c) Not so often another materials (cotton,
polyester etc.)
¾ In one hosiery product usually several
materials is used (till 6 different yarns)
Mostly used materials for course products:
a) Spun yarns of cotton type (cotton, viscous striz,
blends)
b) Spun yarns of wool type (wool, acrylic, viscous,
polyester, blends)
c) Multifilament, often textured (polyamide,
polypropylene etc.)
d) Elastomeric yarns (covered rubber,
polyurethane), used
¾ In welt only
¾ In all product (excellent elasticity)
Mostly used materials for course products:
Combination of materials may bring better
properties and user comfort. Examples:
¾ Polypropylene inside and cotton outside keeps the skin
dry but allows sweat to evaporate.
¾ Plating of spun yarns and multifilament increase
product durability.
1.5. Welts
¾Quality welt should meet next demands:
¾To be fast (upper border ready for use)
¾No or low curling
¾Suitable stretchability
¾Double cylinder machines may produce doublefaced (rib) structure that is ideal for welts.
¾Single cylinder machines are able to knit singlefaced structure only.
Mostly used types of welts:
a) Rib welt (1x1 rib structure) with fast border (starting
courses), great stretchability, often with elastic inlayed
yarn.
b) Inturned (tubular) welt formed by transfer of kinks of
the yarn in some of initial course again on knitting
needles after knitting double length of final welt.
1.6. Shaping of heels and toes
¾Heels and toes could be knitted as:
¾ Reciprocated, knitted on reverse movement of the
needle bed and creating “3-D” pouch on about one half
of the product.
¾Rotary producing only tubular fabric.
Examples of heels
¾Reciprocated
a) 3-D pouch on about one half of the product.
b) Part above the pouch could be reinforced.
¾Rotary
c) Producing only tubular fabric with inserted additional
courses on about one half of the perimeter.
d) Only reinforced and shaped by thermal setting later.
Examples of toes
¾ Reciprocated
a) Knitted in the same way as reciprocated heel but sawn together
later.
b) Similar toe with inserted a group of rotation courses.
¾ Rotary
c) Only reinforced tubular part is finalized by sewing. The seem
may be led from left to right side or from above down.
1.7. Shaping of legs
¾The number of needle in circular needle bed is
done. This fact limits changes of product diameter.
Basic and generally used possibility is change of
stitches length.
¾The change of the yarn consumption is connected
with the change of wales and courses density and
so as well with fabric diameter.
1.8. Used knitted structures and designs
¾Mostly used single-faced structures (from single
bed machines):
¾Plane structures
¾Plated structures
¾Plush structures
¾Laid-in structures
All in different modifications
1.8. Used knitted structures and designs
¾Mostly used double-faced structures (from double
bed machines):
¾Plane double-faced structures
¾Rib structures
¾Purl structures etc. in different modifications and designs
¾Heels, foots and toes are knitted in plane singlefaced structure. The reason is relatively flat surface
and low thickness and so better comfort of user.
1.9. Closing of toes
¾Product of circular machine is ended by tubular
open part and before usage the toe need to be
closed. Next two possibilities are important:
¾Closing the toes by sewing or linking on product
finalization.
¾Closing the toes when knitting on circular machine.
There are several used principles.
1.10. Standardization of hosiery products
¾Some chosen ISO standards:
¾ISO 5971:1981 Size designation of clothes – pantyhose
¾ISO 5971 (CSN 805044): Marking of sizes of hosiery
tights
¾ISO 7070 (CSN 805045): Marking of sizes of hosiery
products
¾ISO 8117:2003: Textile machinery - Knitting machines
- Nominal diameters of circular machines
1.10. Standardization of hosiery products
¾ In Czech Republic next standards are relevant:
¾ CSN 804159: Elastic medical tights and compressive products
¾ CSN 805801: Standard stockings, half-hoses, …, classification
¾ CSN 805802 EN 13770: Measuring of resistance of hosiery
products in abrasion
¾ CSN 805810: Fine stockings, half-hoses, socks and footlets
¾ CSN 805841: Course tights, regulation and classification
¾ CSN 800863: Measuring of weight of knitted products
¾ CSN 800864: Measuring of dimensions and appearance of
hosiery products