Softflow Dyeing Machine – Woven and knit goods of various kind
Processing capacity: Weaight:
Min. 1 Kg or above
Cloth Speed:
Variable Speed Control
Liquir Volume:
10 – 60 Liters or higher
Max-working Temperature:
130 C or higher
Material of Machine:
Stainless steel
Heating/ Cooling
Heating at Below 0.5 to above 4
°C/min and cooling below 3 °C/min
Liquor preparation bath
Min. 10 L
Liquor preparation bath
Min. 10 L
Dye Spots-
Definition and Causes:
This common problem and defect can be caused by one or a
combination of the following:
Undessolved dyes, especially if dye granules and powder instead of liquid dyes are used. Read about Woven Fabric Jigger Machine
Incorrect use of Defoamer chemicals. In certain dye
procedures due to the machine’s high pressure and temperature, the interaction
of some chemicals produces a large volume of foam which can inhibit the
fabric’s rotation and movement. To remove this, de-foaming chemicals are used.
Incomplete removal of these foams can sometimes cause a build-up of coagulated
small particles on the fabric.
Incorrect use of Carriers in Polyester dyeing. Generally
Carrier type chemicals are used to facilitate the Disperse dye exhaustion in to
the fibers. At certain low temperatures, due to the condensation, unwashed
droplets of these chemicals can cause spots on the fabric. (Normally lighter
than the ground color).
There are other causes that could create dye spots. The above
mentioned are the most common in the industry.
Softflow Dyeing Machine Preventive Suggestions:
The use of correct procedures and chemically compatible dyes
and chemicals is a critical part of the dyeing process.
Corrective Measures:
Depending on the type of fabric, in most cases, a high
temperature scouring using
Dispersing chemicals, Phosphoric acid, and soda ash will remove the spots.
Poor Crocking-
Definition and Causes:
The transfer of dyes from one fabric surface and causing the
staining of another fabric surface through rubbing action is referred to as
Crocking and is evaluated using a standard Grey Scale system.
This is often caused by the incomplete removal and cleaning
of the left-over dyes from the fabric surface in the after-treatment process.
In the majority of dyeing processes, most of the dyes are
either fully absorbed or exhausted by the fabric (with the exception of pigment
dyeing). The left-over dyes need to be removed thoroughly.
Preventive Suggestions:
A complete after-treatment in the form of Reduction Clear
(for Disperse dyes), Fixation (for Direct and Acid dyes), and Soaping (for
Reactive dyes) must be given to minimize the staining problem.
Corrective Measures:
In most cases, repeating this after-treatment will improve
the crocking properties of the fabric.
Poor Color Fastness-
Definition and Causes:
Generally, the ability of a dyed fabric to retain its color
is referred to as Color Fastness.
This ability is normally measured in terms of fading due to
exposure to washing, perspiration, light sources, etc.
Color Fastness properties of fabrics which are also
evaluated by the Grey Scale system are adversely affected by the following:
Incomplete color fixing in direct dyeing process, reducing
the wash fastness.
Incomplete fabric soaping in Reactive dyeing, reducing the
wash fastness.
The use of Alkali sensitive dyes, reducing the perspiration
fastness.
The use of UV sensitive dyes or incorrect PH values,
reducing light fastness.
The use of dyestuffs which have poor overall fastness
properties.
There are other factors which can adversely affect dyed
fabrics color fastness. The above mentioned are the most common causes.
Preventive Suggestions:
To ensure a higher level of color fastness is achieved, all
technical aspects of dye and procedure selection must be examined and considered.
Corrective Measures – Softflow Dyeing Machine:
Based on the type of dyes used, the use of an appropriate
rewash will improve the required fastness.
Pad Steam Dyeing Machine -Plato rage 60% to 100% FabrSTheed Variable Speed Control Dwelltime in steamer Dwell time Min. 20 Sec or lower – Max. 90 seconds or higher Pad Pneumatically-Controlled, Maximum pressure 1-6kg/cm or above, NBR rubber with 70o Shore Steami amber Insulated, Max. Temperature Max 100°C or higher., Pressure 0.5mPa or above Display Digital display temperature indicator Steam Generation External Steam Generator Included Display Digital display of parameters Width Min 500 mm or above
Washing compartments Min. 4, with direct steam heating and temperature regulator Fabric take up/ batching system included Parts to be included: IR pre dryer, Steaming chamber, Steam generator
Localized Holes-
Definition Pad Steam Dyeing Machine:
The chemical reaction between the knitting oils ( see section 2 I ), left on the fabric and the Hydrogen Peroxide which is used in the preparation stage of dyeing, at higher PH levels of 7 to 13, results in the weakening of the fibers in the oil stained areas. Read about Woven Fabric Jigger Machine
This weakening of the fibers will eventually, during the
course of the dyeing process, cause localized and sporadic holes to appear.
Preventive Suggestions:
The use of water soluble knitting oils is strongly
recommended.
Yarn lubricants, especially with open-end yarns, need to be
checked to make sure the non-silicone types are used.
Corrective Measures:
For this problem no corrective measures are available.
Spandex Decomposition-
Definition and Causes:
The use of strong alkali in the preparation stage of the
dyeing process and in Reactive dyeing systems where PH values of up to 13 are
required is the main cause of the weakening, loss of elasticity and eventual
breakage of Spandex yarns.
Preventive Suggestions:
When dealing with Spandex yarns, specifically the bare
(uncovered) types and at finer counts, the use of strong alkali solutions must,
to the extent possible, be avoided.
Corrective Measures:
For this problem no corrective measures are available.
Caustic Burns-
Definition and Causes:
This is caused by the sudden exposure of areas of the fabric
to undiluted Sodium Hydroxide (caustic soda) during the dye process.
Here, due to the process of the partial “caustisization”
that takes place, these areas, after dyeing, appear on the fabric as color
intensified blotches.
Preventive Suggestions:
using a “dosing” system of delivery. Using this system, regulated and small pre-determined amounts of chemicals, at pre-determined rates, can be delivered to the dye machine.
This will prevent any possibility of fabric damage.
Corrective Measures:
For this problem no corrective measures are available.
Crease and Rope Marks-
Definition and Causes:
With medium and heavy weight fabrics, dyed in Jiggers or
continuous dyeing range, the incomplete flattening and smoothing-out of greige
goods’ wrinkles are the main causes of these problems.
With knit and light weight woven fabrics, dyed in the Jet
dyeing systems, the main causes are as follows:
fabric tangle,
machine stoppage, especially at high temperatures,
over-loading the dye machine,
lack of correct lubricants (Fiber to Fiber and Fiber to
Metal types need to be used)
incorrect fabric rotation speed
There are other causes but these are the most common ones.
Preventive Suggestions:
The use of correct dyeing process, considering all the
technical aspects is essential.
Corrective Measures:
Generally, re-dyeing the fabric at higher temperatures and
additional use of lubricants can remove the crease and rope lines.
For severe cases no corrective measures are available.
Metamerism-
Definition and Causes:
Metamerism is basically where the intensity and cast of a
color appear to vary under different light sources.
This is, usually, due to the use of incompatible dyestuffs
in creating a dye formula.
It could also be due to the presence of small particles of
optical brighteners in the fibers.
Preventive Suggestions:
Correct dye selection is a critical factor in reducing this
effect.
Corrective Measures – Pad Steam Dyeing Machine:
For this problem no corrective measures are available.
Thermosole Variable Speed Control NBR rubber with 70o shore, 0.1 0.5mPa, 2 pressure gauges, Total trough capacity 500m1, vapour-pressure type Min. 500 mm
Maximum Temperature 250°C or above Infraredjeating system Min. 12 reflect-type IR heaters, Heating distance 800 – 900mm or above,Fabric distance 70-120 mrr (adjustable) Thermosoling 1500mm or above, 250°C or above, Precision ± 1%. Dryer Drying distance 1800mm or above, Temperature 100 180°C, Fabric take up/ batching system included Circulation air speed Min 4 m/s or lower — Max. 15 m/s or higher. Read also Woven Fabric Jigger Machine
Chafe Marks-
Definition and Causes:
This defect appears on the fabric as longitudinal crushed
and discolored areas.
It is normally caused by the sudden stoppage of the fabric’s
movement and rotation during the dye process.
Preventive Suggestions:
To the extent possible, the stoppage of fabric’s movement
and rotation must be kept to the minimum.
Corrective Measures:
For this problem no corrective measures are available.
Salt and Mineral Deposits-
Definition and Causes:
In certain dye procedures, particularly Reactive, a large
amount of Sodium sulfate and other types of salts are used to facilitate and
assist the dye absorption and exhaustion.
Insufficient washing and rinsing during the final stages of
the dyeing process will result in accumulation of white powdery residues on the
fabric.
Preventive Suggestions:
A thorough rinsing of the fabric in the last stage of dyeing
using a strong sequestering chemical is always recommended, particularly when
more than 6 grams/liter salts are used.
Corrective Measures:
With dyed fabrics that exhibit these types of contaminated
areas, a sequestering based rewash process will correct the problem.
Excessive Surface Shine (Luster) and Moiré (Water Mark)-
Definition and Causes:
Intensified, visible, and uniform reflection of light from
the surface of a fabric is referred to as Luster.
In a non uniform and random pattern this effect is known as
Moiré or Water mark.
This problem occurs mainly on fabrics made of synthetic
textured filament yarns and is mainly due to a very small displacement of
fibers within the loops and stitches.
This principle is sometimes used to create the water mark
effect on certain silk fabrics using Calendaring equipments.
Preventive Suggestions:
To the extent possible, synthetic fabrics that are more
susceptible to having this problem must be processed at a relaxed and tension
free environment.
Corrective Measures:
The excessive shiny surfaces and the Moiré can not be
totally removed. However, by reducing and inhibiting the light reflection this
effect can be minimized.
To achieve this, a microscopic layer of a dulling chemical,
(usually Titanium Dioxide), is padded on to the surface of the fabric in the
finishing stage.
This chemical, however, will affect the softness of the fabric and should be used in small quantities.
Color Change Due to Incorrect Drying Temperature-
Definition and Causes:
Uneven or excessive application of heat on to the surface of
the fabric during the drying process may cause one or a combination of the
following:
One side of the fabric to have a different shade. This is
due to the malfunction of the heating chambers circulation mechanism
Complete and overall change of shade and/or cast. This is
due to the fact that in making the dye formulation certain “heat-sensitive”
dyes are used
Partial removal of color. This is due to the process of
sublimation
Yellowing of white color due to scorching and the use of
incorrect softeners
Preventive Suggestions:
Prior to the start of the finishing process the following
need to be established:
The types of dyed used in the dyeing process with regards to
their temperature threshold
The fabric type and selecting the appropriate temperature
range
Side-center-side temperature variation using heat-sensitive
strips
Corrective Measures:
In most cases re-bleaching or re-dyeing will correct the
problem.
Sublimation-
Definition and Causes:
The separation of the surface dyes in a gaseous state off of
the fabric and their transfer or relocation on to another surface in a solid
form is referred to as dye sublimation.
During the drying process, if a light color is dried in the
same machine, after a darker color, the darker dyes (in a gaseous form) that
may have remained in the machine can get redeposited on to the lighter color
(in solid form) causing blotchiness or discoloration.
Preventive Suggestions Thermosole :
During the drying process care must be taken to ensure that,
to the extent possible, fabrics of same or similar shades are dried in
succession.
Screen Repeats: Rotary Printing Machine -Lab-Scale Rotary Printing Machine Min. 10 m/min or Higher Min. 500 mm Min. 10 m/min or Higher Min. 500 mm
Screktipe: Rotary and Blade/Rubber Min. Sarrpie size Min. 60×128 cms or higher Can be used for flat bed printing Squeegee Rod type, Blade type Electromagret strength 1-100%
Pre Production Procedure
PURPOSE
The purpose of this procedure is to ensure that potential risks involved in the production of future production are assessed and documented and that all standards and specifications are clean. Read also Printing and Packaging Machine Spare Parts
SCOPE
This procedure applies to all styles.
RESPONSIBILITY AND AUTHORITY
It is the responsibility of the Pattern Technical
Manager to ensure the implementation of this procedure.
PROCEDURE
Once the customer approves contract seals,
the internal pre production meeting can commence. A factory pack will be sent to the factory
with a duplicate contract seal so the factory can prepare for the meeting. The meeting can take place in Production
unit.
In attendance should be:
Pattern Technical Manager,
Quality Assurance Manager,
Operation Manager,
Industrial Engineer,
Garment Technical Assistant,
Fabric Technologist,
Merchandising,
Head Mechanic,
Cutting Room Manager,
Training Manager,
Production Manager,
The meeting will follow the pre production agenda taking into onsideration comments made about the risks during development, possible risks nvolved concerning the production of garments for the season ahead, machine capabilities, key quality points / availability’s and training / skills required are discussed.
Components are categorized in 4 main areas:
Planning
Pre manufacturing
Manufacturing
Finishing
Bulk Component Approval Procedure
PURPOSE
The purpose of this procedure is to ensure
that bulk components are signed off and approved prior to bulk production.
RESPONSIBILITY AND AUTHORITY
It is the responsibility of the Pattern
Technical Manager, Quality Manager, Fabric Technologist & Merchandiser to
ensure the implementation of this procedure.
PROCEDURE
On receipt of Product Spec the relevant Purchasing Clerk orders trims required.
On receipt of trims the factory complete 4 bulk component cards containing:
Thread approvals;
Fastenings;
Bought in components;
All sew in labels;
UPC labels / fabric composition stickers;
Box end labels / bag seal;
Button / swing tickets;
Bag Reference, relevant to style / Price Sticker / Hanger / Attachment etc.The Pattern Technical Manager, Quality
Manager, Fabric Technologist & Merchandisers will sign 4 bulk component
cards. These are to be distributed as follows.
One to North Street,
One to Trim Stores,
One to Production,
One to Style File,
This allows bulk cutting when bulk
authorisation is issued.These Bulk Component Cards are kept for
reference:By the factory and in the Head Office Style
File
In order to ensure color fastness and wash durability of a pigment printed fabric a complete curing process must take place. Read also Printing and Packaging Machine Spare Parts
This is achieved after the printing process and in the drying stage where the print paste, through the binder’s fusion process, binds with the surface of the fabric.An incomplete curing will cause one or a combination of the following: Cracking of the printed areas, particularly if thicker pigment paste is used Flaking of the pigment paste Poor crocking in both dry and wet state Poor wash fastness and durability
Preventive Suggestions:
The curing temperature often depends upon the type of the
base fabric, the extent of the coverage, the thickness of the paste and the
type of binders used.However, as a general rule, for an effective curing to take
place, the printed areas need to be exposed to temperatures of no less than 360
degrees Fahrenheit for approximately 8 to 10 seconds.
Corrective Measures
For this problem no corrective measures are available.Incomplete Steaming and Fixing of Wet Prints-
Definition and Causes
When using the wet print process it is important to ensure a thorough and complete steaming process is carried out. This is done to facilitate the dye absorption and establish sharp print definition. Failure to do this will result in one or a combination of the following:
Lack of full dye exhaustion
Poor crocking
Poor color fastness and wash durability
Preventive Suggestions
Correct steaming process must be used. Prior to printing the
fabric must be checked for the presence of An-ionic softener residue. Any
left-over residue might affect the steaming procedure.
Corrective Measures
For this problem no corrective measures are available.Incomplete Removal of Base Color in Discharge Printing-
Definition and Causes
The basic premise of discharge printing, which is done on an already dyed fabric, is to remove the dyed base, in pre-determined areas, and to replace it with a new color thus creating a printed pattern. This type of printing is normally done on synthetic and cellulose fabrics where lighter shades need to be printed on a darker ground color. The incomplete removal of the base color will result in a lack of print sharpness and definition.
Preventive Suggestions
The use of appropriate chemicals and at correct conditions
is essential.The chemicals that are used are of the” reducing” types and
must be used, in most cases, in an alkali stable condition. Any presence of acid based components may lead to the
decomposition of the reducing agents.
Corrective Measures
For this problem no corrective measures are available. Incomplete Pattern Transfer in Heat Paper Transfer Printing-
Definition and Causes
Heat paper transfer printing is a common process predominantly used on synthetic fabrics. It is a delicate process but it can be performed at very high rates of production. It is done by placing the especially constructed patterned papers on to the surface of the fabric and through the application of heat cause the transfer of the patterns from the paper to the surface of the fabric.
The most common problem with this process is the incomplete
transfer of patterns which is due to the inappropriate finish of the fabric.
Preventive Suggestions
If the fabric is contaminated with certain silicone softeners and resins, this transfer process may be adversely affected.
Corrective Measures
For this problem no corrective measures are available.
