Films for lamination: properties, types, how to choose it

Lamination (pressing) is a simple process, and it seems that with the level of modern equipment and the variety of films, there should be no problems at all. Know, put sheets into the laminator, and take away the product covered with a hard, durable shell. But sometimes it is the wide choice that often plays a cruel joke on the consumer. Have you ever encountered a film that curled or delaminated after pressing? There may be several reasons for such a marriage, but two main ones can be considered. This is an incorrect selection of film and non-compliance with lamination technology.

In this article we will tell you what films there are for lamination, how the lamination process occurs, how to choose the right laminator and film for it, and answer other frequently asked questions.

Why do you need laminating film?

The main task of laminating film is to protect the information carrier from damage. And she copes with it with a bang, extending the life of paper (cardboard, plastic) for decades. The following items pass through lamination: certificates and price lists, certificates and evacuation plans, insurance policies and important drawings, menus and maps, identity cards, passes and travel documents, advertising products. And a couple hundred more products from the printing (and other) industry. This rigid packing material:

Protects the product from water, grease, chemicals, dust, and mechanical damage.
Gives products a presentable appearance, improves image quality (“developing effect”).
Helps avoid counterfeits.

Structure of lamination film

High-quality laminating film is made using the co-extrusion method and usually contains three layers. You can also find two-layer films on sale. Their cost is low, but they provide poor protection - they wrinkle and delaminate. Let's look at the structure of the film layer by layer:

1st layer - base:

Polypropylene (BOPP). Elastic, soft and thin film, with a thickness of no more than 43 microns. Used in industrial roll lamination. Available in both glossy and matte.
Polyester (PET). Universal, widely used in batch lamination. Can be used for both single-sided and double-sided lamination. Refers to rigid films with a high degree of transparency.
Polyvinyl chloride (PVC) is a very plastic and UV-resistant low-melting material. All texture laminating films are made on the basis of PVC.
Nylon - less common than BOPP or PET. It does not curl and can change its geometric dimensions along with the carrier when cooled and heated. Purchased for single-sided lamination of soft book covers.

The 2nd layer - intermediate - is used as a link between the base and the adhesive layer. Most often polyethylene is used for this purpose.

The 3rd layer - adhesive - is made on the basis of a low-melting polymer, for example EVA, H-EVA. When heated, it exhibits adhesive properties. The composition may include: rubber latexes, polyvinyl chloride or polyacrylic alcohol, glycerin, etc. The final composition depends on the type of base and intermediate layer. The main requirements are that the adhesive polymer must be transparent and have good adhesion.

Film texture

An indicator such as texture allows you to enhance the optical effect of an image on paper or cardboard. The following types of films are produced:

Glossy. Emphasizes the clarity of lines, adds color saturation to photographs and advertising printed products. But its surface is reflective, so it is not suitable for text documents. Plus, scratches on the gloss are also clearly visible.

Glossy Lamination Film

Matte. Used to protect documents and business cards. The film becomes cloudy due to the adhesive layer. After pressing, the glue goes into the pores of the paper and becomes transparent. Scratches on the shell are almost invisible, but the colors are somewhat muted by this material.

Matte film for laminator

Texture. Imitates the surface of various materials. You can read more about this beautiful but expensive film in one of the sections of this article.

Lamination film with linen texture

What can be laminated? Useful tips

Most often, documents are laminated. But if you think about it, lamination can be used for more than just storing boring official papers. So, what can be laminated, besides documents:

Business card. It will be a pity to throw away a beautiful laminated business card - perhaps it will even help you in business.
Bookmarks. Do you have a beautiful paper bookmark, but it won't last long? Laminate it and use it for the rest of your life.
Children's drawings, crafts. Give your children the opportunity to admire their early work many years later, while keeping it in perfect condition.
Greeting cards from the most dear people. A laminated card will still look like new in 30 years.
The most precious letters from family and friends.
Plans (to-do list, menu for the week, etc.). Laminating your weekly menu and sticking it on a magnet will give it a solid look. It might even help you stick to it.
Labels for cabinet compartments, food storage containers, etc. will help you systematize your household.
Tables, rules, theorems for schoolchildren. Is your child having trouble learning the multiplication tables? The back of the notebook looks boring. Laminate it beautifully and hang it in the kitchen - while eating, the child will probably glance at the table, and learning will go faster.

Hot and cold lamination

Depending on the way the film is bonded to the surface of the paper (cardboard, plastic), this packaging material is divided into films for hot and cold lamination. The fundamental difference between these materials is the composition and melting temperature of the adhesive adhesive layer. How do these two processes occur?

Hot lamination.

The film passes through the heating element of the laminator (plate, shaft), where the polymer adhesive applied to its base melts at a temperature of 70-130 0C. Immediately after heating, the laminate is passed through pressure rollers, where under pressure it diffuses into the surface of the paper, becoming one with it.

Laminator for hot lamination

Cold lamination

This method is used when there is a risk that the heat will damage the print or melt the media, such as plastic. Therefore, the heating element is not turned on during cold lamination, and the activation of the adhesive layer and the joining of the film occurs solely due to the pressure of the pressure rollers rotating at a speed of 1-1.5 m/min. Depending on the thickness and type of base, the pressure may vary, but on average it is 2-4 bar.

Cold and hot laminator

There is also a division into single-sided and double-sided lamination. And if a product sealed on both sides is not afraid of moisture and can be used outdoors, then the same cannot be said about paper laminated on only one side - it can only be stored in the office. Plus, such a film, as it shrinks, tends to curl. You can avoid this defect by purchasing a laminator with a device for straightening the finished sheet.

Let's take a regular file...

In order for a document to be preserved, it must be “hidden” in film. Is it possible to laminate paper with a file at home? In fact, this will no longer be a complete document protection, since the thickness of the film in the file is low. However, this method can also be applied in life.

What does that require? You need to have an iron. The required sheet is placed on the file. You need to cut out two pieces that are 1 millimeter larger on all sides than the desired document. Then the paper is hidden between these films, the edges of which are slightly bent. Now you need to heat the iron. It should be passed over the workpiece only once, but firmly, with pressure. Then the paper will be securely hidden under the film. If you go over the iron several times, you may glue the file in the wrong way. To avoid accidentally connecting the film and the iron, it is better to leave a sheet of white paper between them.

Batch and roll lamination

The type of laminator is determined by the type of consumable material (roll, film).

Roll or wide format lamination.

Used to protect paper or cardboard in A3-A0 format. The consumable material is a film with a thickness of 24-60 microns, fed simultaneously from two rolls located above and below relative to the product being laminated. The roll width varies between 300-1650 mm. Its footage ranges from 1000 to 3000 m. Large-format lamination is used in enterprises with large volumes of post-printing processing.

Large format lamination

Batch or envelope lamination.

The paper is encapsulated into a ready-made package - two sheets welded together on one of the narrow sides. A film bag with a thickness of 60-250 microns extends beyond the paper by 3-10 mm. Batch film is produced in a specific format - A7, A6, A5, A4, A3. When we talk about the format of a film, we mean the format of the paper inserted into it. The batch laminator is used to protect printed products produced in small quantities (in the office and at home).

Batch lamination

If you don't have time to laminate, use synthetic paper

©Made-in-China

Today, so-called “synthetic paper” is becoming popular. Because it is made from chemical fibers, it has properties that set it apart from regular cellulose paper: waterproof, grease-resistant, strong (unlike regular paper, it is very difficult to tear) and durable. At the same time, it retains all the useful properties of ordinary cellulose paper: you can write on it with a pen, draw, print on it, etc. If you don't have the time or desire to laminate, just use synthetic paper. True, it will cost you a pretty penny - synthetic paper is noticeably more expensive than regular paper.

About texture lamination

Texture films are made on the basis of PVC - an elastic material with a low melting point. Their thickness varies between 40...50 microns. “Leather”, “sand”, “canvas”, “grain” are the most popular embossing, but there are also unusual ones - frosty patterns, holograms, crystals. Such packaging material is much more expensive than conventional matte or glossy film. It can be wrinkled, twisted, it is not afraid of UV rays and creasing. Its only drawback is its high price, so for large quantities it is too expensive to use texture film. It is bought for laminating wedding photo albums, souvenirs, valuable posters and posters.

Texture Laminating Film

Interesting. A new technology has emerged that will reduce the cost of this luxury packaging. The GMP company has developed a series of laminators in which, if necessary, the smooth heating roller can be replaced with an embossing one (with a texture applied to it). Any design can be engraved on the shaft - from snowflakes to a logo or company name.

What is it made from?

Lamination film consists of 2 layers:

plastic (protective layer);
glue (because of it, the film appears cloudy or gray before use)..

Some manufacturers have gone further and added a 3rd layer. This is a layer between the plastic and the glue, which provides additional protection against fading (UV rays). Such copies are much more expensive.

Note! Cheap films have a 50:50 layer ratio, but this increases the risk of glue leakage. The plastic layer should be dominant.

The top protective layer is made of:

polyester (PET)
polypropylene (OPP);
PVC;
vinyl;
nylon.

The material of manufacture can affect the rigidity and protective functions of the layer. The best option would be PVC.

Questions and answers

How to choose a laminator for your home?

For personal purposes, as a rule, they buy an A4 format bag laminator. When choosing, pay attention to the following nuances:

Thickness. If the equipment is designed to work with a film of 50-80 microns, and you put a laminate of 100-150 microns in it, then the adhesive layer will not melt and will not adhere to the paper.
Number of pressure rollers. In the simplest models, one pair of shafts is installed. Office and good personal laminators (the best option) are equipped with two pairs of shafts, while professional equipment is equipped with a system with three (or more) pairs of shafts.
Modern models can operate in both cold and hot lamination modes.

Pay attention to the options offered by the manufacturer: the number of temperature modes, the ability to change speed, the presence of reverse, memory, and self-shutdown functions.

Why do air bubbles form in the film after lamination?

For hot lamination:

The temperature of the heating rollers was set too high. It is necessary to reduce it to the parameters recommended in the instructions.
The operation of the laminator should be continuous whenever possible. When idle, the center of the upper heating roller warms up more than the edges. This difference can reach 30 0С and affect the quality of the product.
Air bubbles form on solid fills and on printed products from which the setting powder has not been properly removed.

For cold lamination:

Try increasing the clamping pressure or slowing down the rotation speed of the shafts.
The product can be placed in the laminator only if it has been stored for at least a day after printing.

Why does the laminator use several temperature modes?

The denser the film, the higher its heating temperature should be. For example, if the thickness of the consumable material is 75-80 microns, it needs to be heated to 105-110 0C, and if the film thickness is 175-250 microns, then to 130 0C. Home devices, as a rule, have only one mode - for 80-125 micron film. Industrial - up to five. Particularly advanced models may have one mode, and the heating temperature is adjusted by changing the speed of passage of the material through the shafts.

How to choose the right film for lamination?

The type of film is chosen depending on the task at hand and the capabilities of the laminator:

A thickness of 75-80 microns (polypropylene films) will provide basic protection against dirt and moisture. Used for laminating office documents.
When the thickness (polyester) increases to 100-125 microns, the media will not wrinkle or break. This material is used for making presentations, business cards, certificates, and diplomas.
And finally, dense films, 175-250 microns thick. Their use guarantees the consumer high rigidity of the product (plates, badges, passes) and its protection from the most unfavorable conditions.

There are printing products and films that it is better not for a beginner to handle. These are: paper with a density of less than 80 g/m2, cardboard thicker than 3mm, uncoated offset paper, tracing paper, materials that decompose at temperatures of 75...90 0C

What happens if you use a film from another manufacturer rather than a branded one?

It is best, of course, to use films designed specifically for a specific laminator model. Well, or at worst, choose a film in the same price category as the branded one. When purchasing, keep in mind that many Chinese manufacturers save on the intermediate polyethylene layer. To increase film thickness they apply too much adhesive polymer. Its excess spreads, gets on the shaft, and leads to “chewing” and stopping the device. When choosing a material, pay attention to the technology used to make the film. The direct method, which is used to produce cheap and thin films, involves applying an adhesive layer of plastic directly to the substrate. The tensile strength of such a film does not exceed 2 kgf/cm2. With the primary coating method, an intermediate layer is made between the base and the glue, which improves internal adhesion and increases the tensile strength to 4 kgf/cm2.

Don't know which company to choose? Choose leaders - GMP, FELLOWES, GBC, ProfiOffice, D&K, Bulros, Attalus.

How to properly laminate a document using the batch method?

Turn on the laminator. Set the recommended temperature. For hot lamination, set the switch to the “HOT” position and wait until the laminator warms up (there is an indicator indicating the end of heating). Place the film and paper in the tray. The laminated sheet is fed into the device with the sealed edge first to prevent distortion. For reliable pressing, the film at the edges must be 0.5-1 cm wider than the paper carrier. If you need to return the sheet from the laminator, press the reverse button. Once the process is complete, stop feeding and allow the laminated paper to cool for 30-40 seconds. This is how hot lamination is performed. For cold lamination, you need to switch the switch from “HOT” to “COLD” mode and wait until the machine cools down. Otherwise, the technologies of batch cold and hot lamination are no different.

In conclusion, we would like to say that, as with any other packaging material, the laminate buyer constantly has to balance between price and quality. But if he does not know how to properly configure his ultra-modern laminator, and does not know how to choose film for a specific task, then his marriage curve will steadily creep up. (It is not enough to just gain knowledge; you need to find an application for it. It is not enough to just wish; you have to do it. Goethe).