A plastic bag is a product made of a film designed for packaging, storage, and ease of movement of various types of goods. It is applied to production, trade, and daily life.
When choosing to package your products, you must consider the thickness (density), dimensions, style, and the need for a logo.
The manufacturer calculates the thickness in such a way that product quality is not affected, the package is not torn during the transfer of goods. The reduction in thickness is not always related to it carrying capacity. The raw materials used directly affect the strength of the packaging. For example, low-density polyethylene is cheaper than high-pressure polyethylene. With the same density, HDPE packages are stronger than PSDs. Lack of low-pressure polyethylene – not suitable for carrying sharp objects. But it is suitable for a bubble mailer as it doesn’t normally carry sharp objects.
Too high a density (thickness) of bags can degrade the quality of the package. Seam welding equipment has some limitations. At a density of 100 microns and above, the unit will not cope, and the seam may open.
What thickness to choose a plastic bag?
Often a situation arises when the buyer cannot decide what density of packaging he needs.
The choice of the thickness of the plastic bag depends on the type, weight of the products for which it will be used:
- 5-10 microns – packaging of fruits, vegetables, groceries, and haberdashery goods weighing up to 1-2 kg, usually without handles, small T-shirt bags are possible, for example, 20×40 cm.
- 10-16 microns – designed for a weight of 1-4 kg, small, for example, 20×40 cm or 25×40 cm.
- 18-20 microns – bags of this density are used in stores, supermarkets, and shopping centers for packaging and carrying purchased goods. Withstand 4-5 kg.
- 20-30 microns – the optimal density, such containers are used in supermarkets and shopping centers. Withstand weight up to 10 kg in the absence of sharp objects.
- Bags with a density of 35, 40, and 45 microns are suitable for storing and carrying car parts, such as tires or wheels, building materials, and other heavy goods. Load capacity 15 kg.
- Recycled polyethylene bags will save costs by 25-30%. But such a container cannot withstand a large load, it can tear along its entire length, and it has an unpresentable appearance – polyethylene has stains and a dirty gray or beige tint in the light. Recycled bags are suitable for making black packaging, not designed for heavy loads, and suitable for garbage.
The most simple, inexpensive, and in demand in all grocery stores is Production from HDPE and PVD. Designed for lightweight. Designed for packaging food products in small batches (PND) or ensuring the safety of perishable food products (PVD). The thickness of the packaging bags is from 6 to 12 microns. Transparent polyethylene “packings” of the “roll” type come in two sizes: 25×35 cm and 25×40 cm.
With a small thickness, such packaging is strong, durable, and practically does not stretch during the process of carrying heavy goods. The design allows you to withstand a lot of weight, and side folds (folds) provide roominess.
Even with a small film thickness, the T-shirt handles do not require reinforcement, the use of a film of higher density allows significant savings.
With punched handle
Made from HDPE and PVD. The packaging has a rectangular shape, and the hole for the hand (cut handle) is in the upper part. Film thickness – from 35 to 100 microns.
They are divided into several types: with and without a bottom, with reinforced or non-reinforced handles, etc.
Convenient for applying advertising information – logos, images. It is used to distribute promotional products, periodicals, or small souvenirs.
With loop handle
Produced from a film with a thickness of 40 microns and above. High density, absence of side folds, and attractive appearance make it possible to apply high-quality printing on the packaging. Image packs usually have loop handles.
Types of handles:
- The handle, made of the same polymer as the package itself (only denser), is welded on a special machine.
- Rope handle. The ropes are threaded into special holes located in the upper part, fixed with a knot. To increase the load capacity, the holes are reinforced with special caps or several layers of material.
- Plastic handle – made of plastic, attached to the bag with the help of molding. Provides great strength and load capacity.