Receipes for different shades of Denim

Receipes For Different Shades on Denim


A) Black-on-Black
Black-on-Blue

Recipe

Liquid Sulphast Black= 200 gpl
Sodium Sulphide= 20 gpl
Sandozol HSI = 10 gpl
Soda Ash= 10 gpl

B) Blue-on- Blue

Receipe

Liquid Sulphar Navy Blue = 100 gpl
Liquid Sulphast Black= 50 gpl
Sodium Sulphide= 20 gpl
Sandozol HSI= 10 gpl
Soda Ash= 10 gpl

C) Reactive Series

Receipe

01) Ramazol Turquoise Blue G = 110 gpl
Urea= 100 gpl
Swanic 6L= 10 gpl

02) Sodium Silicate= 250 gpl
Caustic Soda = 10 gpl

Ratio of 01) and 02) = 3:1

D) Ramazol Coffee Brown G

Receipe
01) Coffee Brown G = 100gpl
Urea = 100 gpl
Swanic 6L= 10 gpl

02) Sodium Silicate = 250 gpl
Caustic Soda= 10 gpl

Ratio of 01) and 02) = 3:1

E) Ramazol Parrot Green

Receipe
01) Ramazol Turquoise Blue G = 90 gpl
Ramazol Yellow FG = 40 gpl
Urea= 100 gpl
Swanic 6L= 10 gpl

02) Sodium Silicate = 250 gpl
Caustic Soda = 10 gpl

Ratio of 01) and 02) = 3:1

F) Ramazol Blue

Receipe
01) Ramazol Black B = 70 gpl
Urea = 100 gpl
Swanic 6L = 10 gpl

02) Sodium Silicate = 250 gpl
Caustic Soda = 10 gpl

Ratio of 01) and 02) = 3:1

Sewing Problems

Sewing Problems

1. Problems of stitch formation

It gives rise to poor seam appearance and performance

These are

- Slipped stitches
- Staggered stitching
- Unbalanced stitches
- Variable stitch density
- Puckering
- Needle, bobbin or loops thread breakage

a. Slipped Stitches

Arise from the hook or loopes in the machines not picking up the loop in the needle thread.

b. Staggered Stitches

Can be caused by yarns in the fabric deflecting the needle away from a straight line of stitching, giving a poor appearance.

c. Unbalanced stitches

It can reduce the potential of stretch in a seam in a knitted fabric and may lead to seam cracking.

d. Variable stitch density

It arises from insufficient foot pressure in a drop feed system, causing uneven feeding of the fabric through the machine.

PROBLEMS OF PUCKER

Pucker is a wrinkled appearance along a seam in an otherwise smooth fabric. It generally appears as if there is too much fabric and not enough thread in the seam.

Causes of Pucker

a. Seam pucker due to differential fabric stretch

Remember that the upper fabric would tend to move forward by an amount always less than the movement of lower one. This is due to the fact that the lower layer is positively gripped by the feed dog and upper layer is driven by the friction by the lower layer.

b. Differential pucker caused by fabric dimensional instability

The essential feature causing differential pucker is the relative change in dimensions of upper and lower fabric after the seam has been made.

Differential pucker due to dimensional instability may be suspected when the two fabrics being joined are markedly different or when one shows noticeably more pucker than the other.

c. Seam pucker due to extension in the sewing threads.

All sewing threads have some extensiblity and they are extended by the action of the tension devices and pass into seam in an extended state. When removed from the machine they will tend to contract.

When thread extension is proved to be the cause of puckered seam, consideration must be given to the type of thread being used and to the tensiton settings on individual machines.

d. Seam pucker due to sewing thread shrinkage

Cotton sewing threads increase in diameter and shrink in length when wet and these distortions may cause pucker in sensitive fabrics. Synthetic sewing threads have negligible wet shrinkage and should always be used for such fabrics.

e. Seam pucker due to structural jamming

The presence of the seam itself may introduce a distortion. It is in no way dependent on the action of the sewing machine, but it invariably appears as soon as the seam is formed.

As soon as a woven fabric has been constructed so as to be close to the practical weaving limit, that is very less space left between the yarsn either warp or weft ways, it may be extremely difficult to force in any more threads in either direction.

The term 'structural jamming' is given to this type of pucker because it results directly from the act of jamming extra threads into a structure which is already too closely set to accommodate them.

Seam pucker due to mismatched patterns

This is due to the discrepency between the lengths of the stitching lines on the pattern pieces that go together in the seam. Thus there is a difference in the lengths of the cut parts which the machinist is sewing together.

Problems of damage to the fabric along the stitch line

a) Mechanical damage

1. Needles can strike and break fabric yarns and burst the loops in knitted fabrics. For this appropriate set and ball point needles are necessary.

2. Needles should always be as small as possible.

3. Sometimes the combination of the machine speed and nature of the fabric prevents the yarns from moving out of the way of the needle sufficiently fast to avoid damage .To solve the problems either reduce the speed - which means lesser production or ensure that the fabric is adequately lubricated. It calls for having resin finish on the fabric.

- All sample lengths of the fabric should be tested for sewability and the necessary finishes should be specified before the bulk fabric is ordered and bulk fabric should be tested before production to ensure that finishing treatment has been effective.

b) Needle Heating Damage


Needles heating occurs as a result of friction between the needle and the fabric being sewn.

In high speed sewing of dense material, temperatures as high as 300 deg or even 350 deg can be reached.

At this temperature it is possible that the needle may suffer damage and lose its hardness.

Natural fibres in a fabric or thread can withstand these temperatures for a short time.

With synthetic fibres, the position is more critical since the fibres melt at around 100 deg C, polyamide and polyester soften at about 230 deg C and polyacrylics will only withstand temperatures upto 280 deg C.

Overheated needes can
- Soften the synthetic fibres
- Weaken them
- Produce rough seam with
- harsh stitch holes

Melted fibres stick to the surface of the needes
- Increase its friction
- cog the eye and the groove
- No sew
- Skipped stitches

Reduction of Friction
- Reduce the sewing speed
- Changing the shape or surface of the neede
- long seams will ensure more heat build up in the needle
- Jet of compressed air.
- User spun or corespun yarns.

Sewing-9

Thread Sizing

1. Metric Ticket Number system

eg if Nm 60/1 means 60m of it would weigh 1 gm.

of 120/2 means 120 m of it would weigh2 gms. In this case it would have a resultant count of 60 ( i.e. 60 gms) would weigh 1 m.

The metric ticket number of this thread based on a three fold equivalent is then three times that i.e.

Nm 80/2= Ticket Number 120
Nm 30/3 = Ticket Number 30 and so on..

2. Cotton Sewing threads are sized on the cotton ticket number system

eg. 3/60 Ne --> equivalent cT= 20--> Three fold equivalent = 60 ( Ticket Number)

3. Denier system--> Weight in gms of 9000 m of length

Thread Packages

1. Spool

a. Used for domestic sewing
b. Not suitable for delivering thread to high speed industrial machines.

2. Cops

a. Small cylinderical flangeless tubes onto which thread is cross bound for stability.
b. Lack of flanges facilitates regular offwinding from the top on sewing machines.
c. Their small diameter makes them less suited for the faster thread offtake of machines.

3. Cones

a. They contain 5000 m cross wound for stability and good offwinding performance.
b. They give troublefree thread delivery.
c. Ideal in situations where thread consumption is high.

4. Vicone- Contain any spillage

5. Large Package

a. Can hold in excess of 20000 m of spun or corespun thread

6. Container

cocoons: They are self supporting ie. centerless, thread packages.

Sewing-8

Thread Finish


The final aspect of thread construction to be studied is that of surface finish.

The most important finish is lubrication.

The requirement of a lubricating finish applied to a sewing thread is that it should produce a regular level of friction, and that for synthetic threads in particular, it should provide protection from needle heat.

Without a controlled amount of lubrication applied to threads, unacceptable damage would be inflicted on them during the sewing process which would result in thread breaks during sewing and seam breakdown in wear.

A lubricant


- Must not clog the needle eye
- should not stain
- Must allow thread to unwind evenly from the package
- Must reduce friction with m/c surfaces but without creating too much slippage
- Must not react adversly to high temperature
- Must be inexpensive
- Easy to apply to the thread during manufacturing.

Other finishes


- Mildew or rot resistant finish
- Water resistant finish
- Soil Release
- Flammability finish

Terry Towel Manufacturing Process

In addition to what I have mentioned earlier, Terry Towelling is excellently described in this blog.
Replete with pictures, this post replies succintly the various process steps in manufacturing terry towel.

Sewing-7

Sewing Threads

Threads can be

Spun


Threads made from spun yarn have good sewing performance, good dimensional stability and good stitch locking properties in the seam due to their fibrous surface.

Monofilament


One filament of large size. It is harsh on machine and rather inflexible because the cross sectional shape never varies as it would with multifilaments.

Its cut ends are harsh on the wearer. It has virtually no seam grip and stitches tend to unravel easily.

Its good advantage is a translucency which reduces the need for shade matching.

Multifilament Form


Their fineness enables larger thread packages to be used, thus saving operator time changing them.

Corespun


In this a continuous multifilament core is wrapped around a sheath of spun fiber, two or three of these yarns are then plied together.

The majority of these corespun threads consist of a polyester core and a cotton cover.

Sewing-6

Sewing Threads

Selection of sewing threads depends upon the following factors:

1. Performance properties during sewing
2. Performance in the completed garment under conditions of wear and cleaning

Appearance and perfomance of the threads depends upon:

1. Fiber Type
2. Construction
3. Finish

1. Fiber Type

a. Linen- Useful in making strong, rather stiff threads for heavy sweing and also for button sewing.

b. Slk - Advantage- Good appearance and performance, Disadvantage- High Cost

c. Cotton - Good Sewing Performance, Disadvantages- Strength and abrasion resistance are inferior to synthetic threads of equal thickness.
It is more stable at higher, dry temperature than synthetics- less affected by hot needles during sewing.

d. Viscose- 1. Do not have the strength or durability of synthetic fibres. 2. Low tenacity and low strength when wet. 3. High lustre- can be used for embroidery.

Nylon/ Polyester Threads
1. Not affected by rot, mildew or bectaria
2. High Tenacity
3. High resistance to abrasion
4. Good resistance to Chemicals

2. Construction

When the fibres occur in short lengths, they must be twisted together, initially into a single yarn, and then that twist must be balanced by applying a reverse twist, as two or three such yarns are combined to form the thread construction.

- Twist in singles yarn consolidates the strenth and flexibility provided by the fibres themselves.

- Without the reverse twist, known as finishing twist, a conventional thread cannot be controlled during sewing. The individual plies would separate during their repeated passages through the needles and over the sewing machine control surface.

- Remember that the frictional forces acting on a thread during its passage through a sewing machine also tend to insert some twist, predominantly in one direction.

Sewing-5

Needle Point

These are divided into two parts- Cutting points and cloth points.

Cutting Points: These are needed for fabrics like leather where there are no gaps in the structure.

Cloth Points: These are needed for those fabrics where there are gaps in the structure.

Cutting point Neeedles

a. Wedge Point: It produces most durable seam on leather. It resists great stress, the incision lie at right angle to the seam direction and high stitch density can be achieved.

b. Cross Point: Here strength is considerably weakened. The material is likely to tear if stress is at the right angle. The incisions lie parallel to the direction of the seam.

c. Twist Point: The strength is intermediate and the incisions like 45 deg. to the direction of the seam.


Cloth Point Needles

These are used for sewing textile materials rather than the sheet material already described. The points have a round cross section.

The needles are different for the various woven and knitted fabrics.

Knitted fabrics consist of yarns with spaces between them and if a yarn in a knitted fabric is broken the knitted structure may begin to unravel. The requirement in sewing knitted fabrics is :

a. A needle which will slightly deflate the yarns and enter the spaces.

b. A needle of as small a size as possible consistent with needle strength and sewing thread size.

c. A fabric which is sufficiently lubricated that it has flexibility in relation to the movement of the needle.

The shape of the tip of the neele point which best achieves this deflation is a ball shape and the needle is referred to as a ball point needle.

Woven fabric consist of yarns which can have greater or lesser amounts of twist, interlaced with each other at various degrees of density.

For that a needle is needed that goes between the fibres and does not strike and break them.

The shape of the tip of the needle point which best achieves this penetration between the fibres has the appearance of being slighly cone shaped. It is usually referred to as a set point needle.

Sewing-4

Size of Needle

Choice of size is determined by the fabric and the thread combination which is to be sewn.

If needle is too small for the thread, the thread will neither pass freely through the eye nor fit properly into the long groove. As a result it will suffer from excessive abrasion. It may result in

Costly thread breakage in production because the machinist must stop to rethread the needle and possibly also to unpick some of the stitching so that a joint does not show in an important part of the garment.

When sewing heavy plies of material, a fine needle tend to get deflated. It can affect the stitch loop pick up and cause slip stitches, or it can even lead to needle breakage

A break in the situation of multi-needle sewing with fabric running through the folders would be impossible to repair.

If the needle is too large, there will be poor control of the loop formation which may cause slipped stitches.

There will also be holes in the fabric which are too big for the stitches and give an unattractive seam appearance.

In closely woven fabric, there will be a pucker along the seam line due to fabric distortion.

Nomenclature for Needle Size

Metric

d x 100 = Metric Number, where d is in millimeter,

eg. For d = 0.65 mm, number of needle is 0.65x100 =65




Selection of needle and thread size for a particular seaming situation is a question of achieving a balance between the minimum damage due to pucker which is a matter of small needle size and seam strength which requires a substantial needle and thread.

Sewing-3

Sewing Machine Needle

The way in which the fabric is penetrated by the needle during sewing has a direct effect on seam strength and on garment appearance and wearable life.

The functions of the sewing machine needle in general are:

a. To produce a hold in the material for the thread to pass through and to do so without causing any damage to the material
b. To carry the needle thread through the material and there form a loop which can be picked up by the hook on the bobbin case

Anatomy of a Sewing Machine Needle



Butt: It is shaped end of the needle which facilitates insertion into the needle bar or clamp.

Shank:
It is the upper part of the needle which is located within needle bar. It is the support of the needle as a whole and is usually larger in diameter than the rest of the needle for reasons of strength.

Shoulder: It is the section intermediate between the shank and the blade.

Blade: The blade is the longest part of the needle down to the eye. The blade is subjected to the greatest amount of material through which the machine passes.

Long Groove: The long groove in the blade provides a protective channel in which the thread is drawn through the material during stitch formation. Sewing thread can suffer considerably from abrasion during sewing as a result of friction against the fabric. A correctly shaped long groove, of a depth matched to the thread diameter, offers considerable protection to the thread.

Short Groove: The short groove is on the side of the needle which extends a little above and below the eye. It assists in the formation of the loop in the needle thread.

Eye of the Needle: The eye of the needle is the hole extending through the blade from the long groove on one side to the short groove on the other.

Scarf or Clearance Cut: It is a recess across the whole face of the needle just above the eye. This ensures that the loop of the needle thread will be more readily entered by the point of the hook.

The Point of the needle is shaped to provide the best penetration of each type of material.

The Tip is the extreme end of the point which combines with the point in defining the penetration performance.