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A division of Polybags Ltd.

Plastic Bags

Buy plastic bags

Polybags Ltd. is an UK manufacturer and supplier of plastic bags. Other then stocked bags Polybags also offers an easy way of advertising your compnay by customizing plastic bags with your own logo. Go and have a look at the plastic bags page of Polybags Ltd.

What are plastic bags

A plastic bag or plastic pouch is a type of flexible packaging made of thin, flexible, plastic film. Plastic bags are used for containing and transporting food, powder, ice, chemicals, waste, etc. Bags can be preformed, filled and sealed later or can be formed at the filling and sealing operation. A pouch is usually a small or moderate sized bag.

How are plastic bags made

Most Plastic bags are made from polyethylene, more commonly known as polythene, which is made from crude oil and natural gas, non-renewable resources.

The most common way to produce polythene bags is by blown film extrusion, also called the 'tubular film process'. In Blown film production process polythene melt is extruded through an annular slit die, usually vertically, to form a thin walled tube. Air is introduced via a hole in the centre of the die to blow up the into the tube causing it to expand and form a bubble. Mounted on top of the die, a high-speed air ring blows onto the hot film to cool it. The tube of film then continues upwards, continually cooling, until it passes through nip rolls where the tube is flattened to create what is known as a 'lay-flat' tube of film.

This lay-flat or collapsed tube is then taken back down the extrusion ' tower' via more rollers. The lay-flat film is then either kept as such or the edges of the lay-flat are slit off to produce two flat film sheets and wound up onto reels. If kept as lay-flat, the tube of film is made into bags by sealing across the width of film and cutting or perforating to make each bag. This is done either in line with the blown film process or at a later stage.

For more info

For more on plastic bags Packagingknowledge.com is a great source of valuable information.
Or you might be interest in visiting one of our other plastic bags websites.

Clear plastic bags

Clear plastic bags are ideal for bagging up itmes when they are posted as an extra protection, ideal for packing craft items, magazines ,ideal for storing of items, these colud be used for food as well. These bags are string polybags and lightweight.

Heavy duty plastic bags

Heavy duty plastic bags are suitable for multi-uses including food. You could use small plastic bags to pack non liquid food storage or large plastic bags for your items that need protecting. Lightweight and durable these heavy duty poly bags are manufactured in the UK and are available in various sizes.

Biodegradable plastic bags

Biodegradable plastic bags are quickly degraded when thrown out by the action of bacteria, availabel in many different types such as kitchen waste and refuse bags, bin liners, carrier bags and standard bags. As well as biodegradable, degradable plastic bags decompose but by the action of chemicals.

Clear plastic carrier bags

Clear plastic carrier bags are made from a clear low density plastic film, capable of holding up to 3 kilos in weight they are ideal for to show your product. This type of carriers are commonly used in gift stores, boutiques, clothing outlets and other retail stores.

Plastic shopping bags

Plastic shopping bags, or carrier bags, are the most commonly type of shopping bag used. Intended for a single use to carry items from a store to a home these bags are often reused as storage or as a bin bag. Heavy duty plastic shopping bags are suitable for multiple uses such as shopping for havy items or useful as plastic sacks.

Resealable plastic bags

Resealable plastic bags, also known as self-seal bags or minigrip bags are ideal to secure the contents and to avoid leakage or contamination. Resealable bags have a simple plastic ridge that clicks shut and pulls open for continual re-use.