Question 53 (Textile Engineering & Fibre Science)
Consider the following assertion [a] and reason [r] and choose the most appropriate answer.
[a] In a roller printing machine, the doctor blade is closely set over the printing roller
[r] This is to remove the lint collected on the roller
| (A) | [a] is right, [r] is wrong |
| (B) | [a] is right, [r] is right |
| (C) | [a] is wrong, [r] is wrong |
| (D) | [a] is wrong, [r] is right |
[Show Answer]
Option A
Frequently Asked Questions | FAQs
What is roller printing process?
Roller printing, also known as roller printing process or roller printing technique, is a method of printing patterns onto fabric using engraved metal rollers. It is a type of surface printing, where the fabric is passed through a set of rollers, each containing a different pattern, to transfer the design onto the fabric. Roller printing is a popular method for producing large quantities of printed fabric with consistent and repeatable patterns.
The roller printing process typically involves the following steps:
Design preparation: The desired pattern or design is created on a paper or fabric template, which is then engraved onto a metal roller. The roller is usually made of copper or brass, and the design is engraved onto the surface of the roller using specialized engraving tools or machines.
Color preparation: Colorants, such as dyes or pigments, are mixed with a printing paste or thickener to create the printing color. The printing paste is typically made of water, a binder, and other additives to ensure good adhesion to the fabric.
Printing: The fabric is passed through a series of rollers, known as the printing machine, each containing a different engraved roller with a specific pattern. The rollers are coated with the printing color, and the fabric is pressed against the rollers to transfer the design onto the fabric. The pressure applied during printing determines the intensity of the color and the level of penetration into the fabric.
Fixation: After printing, the fabric is typically dried to remove excess moisture and then subjected to heat to fix the color onto the fabric. This may involve passing the fabric through a drying or curing oven, or using other heat fixation methods depending on the type of colorants and fabric being used.
Finishing: After fixation, the fabric may undergo additional finishing processes, such as washing, steaming, or chemical treatments, to improve the color fastness, hand (feel), and other properties of the printed fabric.
Roller printing is widely used in the textile industry to produce a variety of printed fabrics, including apparel fabrics, home textiles, upholstery fabrics, and more. It allows for high-speed production of consistent patterns and offers a wide range of design possibilities. Roller printing is commonly used in conjunction with other textile printing methods, such as screen printing or digital printing, to achieve different effects or combine multiple colors or patterns on the same fabric.