নবি কারীম (সাঃ) বলেছেন,
বান্দা যখন '' লা ইলাহা ইল্লাল্লাহ '' - ' আল্লাহ ছারা কনো মাবুদ নাই ' বলে তখন তা আকাশ সমুহ ছেদ করে যায়, এমন কি আল্লাহর সামনে গিয়ে উপস্থিত হয়, তখন আল্লাহ বলেন স্থির হও, তখন বাক্যটি বলে, আমি কি করে স্থির হব, যে আমাকে উচ্চারন করেছে তাকে এখন মাফ করা হয়্নি, তখন আল্লাহ বলেন, তমাকে এমন ব্যাক্তির মুখ দিয়ে উচ্চারন করিয়েছি, যাকে উচ্চারন করার আগেই মাফ করে দিয়েছি ।
Monday, December 30, 2013
Sunday, December 29, 2013
Saturday, December 28, 2013
General theory of printing
The printing of
textile materials is the application of colour according to a predetermined
design.
The printing
paste which is applied to textile material consists of dye, water, thickener
and hydrocarbon solvent or oil. After the printing paste is applied, the
textile material is usually steamed.
General theory of dyeing
Dyeing is the
process of coloring textile materials by immersing them in an aqueous solution
of dye, called dye liquor. Normally the dye liquor consists of dye, water and
an auxiliary.
The general
theory of dyeing explains the interaction between dye, fibre, water and dye
auxiliary. More specifically, it explains:
Fading
Fading is the
result of some change in the structure of the dye molecule due to absorption of
light, reaction with air pollutants, laundering, dry cleaning and/or other agent.
Fastness to
sunlight: Fading in
sunlight is due to ultraviolet radiation which initiates chemical degradation
of the dye molecule through the loosely held electrons of the chromophores.
Classification of dyes
Dyes may be
classified in two ways:
a. according to
the chemical constitution of the dye molecule, or;
b. according to
the method of application of the dye.
Acid dyes
Acid dyes are
so called because they are usually applied under acidic conditions The fibres most
readily coloured with acid dyes are man-made, synthetic, nylon fibres and the
natural protein fibres (mohair, silk, wool, etc)
Laboratory Dyeing Techniques
A modern dye
house is not operable without support from laboratory work. The laboratory’s
tasks are among others:
-Working out
formulations for new shades, supported by colorimetry and computer color
matching.
-Production
tests on the textile material to be dyed; fastness testing.
Colorfastness of Textiles
Dyed textiles
are exposed to a variety of treatments during subsequent manufacture steps and
later is daily use. Standard test methods have been developed to evaluate the colorfastness.
These test methods are maintained by the International Organization
Standardization (ISO). The standard test methods are published as ISO standard
105. Change in color and staining of undyed adjacent fabric are assessed
visually colorimetrically by comparison with a gray scale of dyed fabric.
Standardization of Textile Dyes
Dyers task is
to give a visual impression to the human eye. The eye is a very positive organ
that can detect very slight color differences. Since dyes are industrial
products, they may contain impurities and colored or colorless by products,
depending on their production process. Dyes are standardized not to a certain
chemical composition but to a defined coloristic value. Consequently they may
be composed of mixture of dyes and may contain shading components. For example
all disperse and cationic blacks are mixtures of dyes.
Dyeing Technology
The goal of
every dyeing is a colored textile in the desire shade homogeneous in hue and
depth of shape, produce by an economic process and which exhibit satisfactory
fastness properties in the finished take.
There are five
steps of dyeing technology:
1. Principle of
dyeing
2. Bath dyeing technology
3. Continuous
and semicontinuous dyeing
Thursday, December 26, 2013
How to Block Websites on Firefox
If you use Firefox as your Internet browser and want to block websites
from being viewed, you will find that Firefox as a standalone web
browser does not have a website blocking feature. However, Firefox
supports the use of third-party add-on programs, and BlockSite is a
third-party Firefox add-on that you can use to make a list of websites
that you want blocked in your browser.
Tips
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Health Tips
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FELTS
A felted fabric
consists of an entangled mass of animal hairs entwined and interlaced in an
irregular manner, without the intervention of spinning and weaving or knitting.
The ability to
form felts is limited to those fibres which possess three characteristics,
namely, a surface scale structure, ease of deformation, and the ability to
recover from deformation. During the felting process, the hairs travel by a
sequence of shrinkage and extension; hence the fibres become entangled with one
another and the mass is drawn together into a consolidated form.
LACE FABRICS
Lace fabrics are
formed by twisting two sets of threads together at intervals; both sets of
threads are warp threads, there being no weft in lace constructions.
The warp threads
are divided into two groups for lace-making, namely, warps and bobbin warps.
The former are wound on beams from which they rise vertically to the lace
roller whereas the latter are wound on small bobbins, with about 120 yards of
yarn on each bobbin. The bobbin warps swing between the true warps, and the
sideways movement of the latter twists the two together. The bobbins revolve on
the verge of a carriage, the bobbin and its carriage corresponding broadly to
the pint and shuttle used in the weaving of cloth. The carriages have an
oscillating movement in comb bars, each of which holds a full number of
carriages both back and front; both comb bars are situated so that the combs
are directly opposite in each bar. With the bobbin threads and the warp threads
rising vertically to the lace roller a pattern are given to the twisted
portions.
KNITTING MACHINES
There are four
types of knitting machine,
(a) the straight bar machine or frame,
b) circular
machines,
(c) flat machines, and
(d) warp knitting machines.
The first three
types are weft knitting machines.
In both the
straight bar machine for weft and the warp knitting, the needles are fixed in
the bar of frame and move collectively. But in circular and flat machine, the
bar does not move up or down, and the needles are not fixed but move in slots.
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