Introduction of printing
Printing is the process of producing multiple copies of a text or image using a printing press or other printing methods. The art of printing dates back to ancient times, with early forms of printing using materials such as wood, clay, and metal.
Lecture Sheet Tariqul Sir
| Introduction of Printing | Download |
| Thickener | Download |
| Styles of Printing | Download |
| Methods of Printing | Download |
| Special Methods of Printing | Download |
| Faults of Printing with Remedy | Download |
| Printing with Different Dyes & Pigment | Download |
| Introduction to Finishing | Download |
| Calendering | Download |
| Mechanical Finishing | Download |
| Mercerization | Download |
| Chemical Finishing | Download |
| Special Finishing | Download |
| Knit Finishing | Download |
Thickener
A thickener is a chemical substance used to increase the viscosity or thickness of a liquid or a paste. Thickening agents are used in a wide range of applications, including in food products, cosmetics, and industrial processes.
In the food industry, thickening agents are used to improve the texture and consistency of products such as sauces, gravies, and soups. They may also be used to stabilize emulsions or to prevent the separation of ingredients.
Commonly used thickening agents in the food industry include starches such as cornstarch and potato starch, gums such as xanthan gum and carrageenan, and proteins such as gelatin and egg yolks.
In the cosmetics industry, thickening agents are used to improve the texture and stability of products such as creams and lotions. Commonly used thickening agents in cosmetics include carbomers, gums, and cellulose derivatives.
In industrial processes, thickening agents may be used to increase the viscosity of liquids to improve their flow properties, to reduce sedimentation, or to improve their suspending properties. They may also be used to thicken coatings, adhesives, and sealants.
Overall, thickening agents play an important role in many industries, improving the texture, stability, and performance of products and processes.
Calendaring
Calendering is a finishing process used in the textile industry to improve the surface properties of fabrics. It involves passing the fabric between two or more rollers, which apply pressure and heat to the fabric, resulting in a smooth and glossy surface.
The calendering process can be done using various types of rollers, depending on the desired finish and properties of the fabric. Some of the commonly used rollers in calendering include:
- Steel rollers: These are smooth rollers made of steel and are used for producing a smooth and glossy finish on fabrics.
- Embossed rollers: These rollers have a pattern or design on their surface, which is transferred to the fabric during the calendering process. This can be used to create a range of decorative effects on the fabric.
- Soft-touch rollers: These rollers have a rubber or polymer coating, which provides a soft and smooth finish to the fabric.
- Heat-set rollers: These rollers are used to set the fabric’s shape and size by applying heat and pressure to the fabric.
The calendering process can also be combined with other finishing processes such as resin finishing, dyeing, and printing to create a range of different finishes on the fabric.
Some of the benefits of calendering include improving the fabric’s surface smoothness, increasing its density, and reducing its porosity. This can result in improved fabric performance, such as increased water resistance, durability, and wrinkle resistance.
Overall, calendering is an important finishing process in the textile industry, providing a range of benefits and improving the aesthetics and performance of fabrics.
