Paper types

Due to today's technical progress as well as the versatile demands on paper, there is a comprehensive range of different types of paper. These are produced and processed in different ways and also have special properties depending on the type of paper. This makes them suitable for different applications. In this blog post, you will find out what types of paper there are and how paper is basically manufactured.

The basics of paper types - the different types of paper

A first rough classification of paper types can be made with uncoated and coated paper. The focus here is on the surface structure and texture of the papers.

Coated papers are finished with a so-called chalk coating, which makes the surface of the paper matt or also glossy. This effect makes the surface appear closed and thus more stable and smooth. This makes it possible to achieve a higher level of detail and quality in printing. Coated papers are also used to create eye-catching type and image effects and when stability is required. With glossy coated papers, a subsequent calendering process gives the surface of the paper more gloss and smoothness. Calendering is a process in which the paper is run through several pairs of rollers of different hardness and materials to achieve the result. This type of paper is preferred for more brilliant colour results as well as sharp contrasts when printing. Matte-coated papers or art papers are used to achieve reflection-free image reproduction with simultaneous high-contrast colour reproduction. They also achieve optimal readability. Matt-coated paper grades are mainly used when the printed products are to appear more discreet but at the same time noble and graceful.

Uncoated papers, on the other hand, have not been synthetically treated, i.e. they have a naturally matt and closed surface structure. They also have a pleasant feel.

The different types of paper, their properties and preferred use

Nowadays, there is an abundance of different types of paper. This is partly due to technical progress, but also to the fact that not every type of paper is suitable for a specific use. For example, thin and water-sensitive stationery cannot be used for outdoor advertising, which is exposed to the elements and UV radiation. Likewise, postcard paper, for example, must undergo a special manufacturing process in order to be able to depict beautiful images on the front and at the same time remain writable on the back. Depending on which print item is to be used where and in which way, different types of paper are suitable for this purpose. We have compiled the most commonly used types of paper for you, although there are plenty of other special types of paper.

1. Coated art paper

One of the classic types of paper is coated art paper, which can be used for all printing processes in digital and offset printing. Coated art paper is available with a matt, silk-gloss or glossy coated surface and refers to all coated papers from 70 to 170 gsm. From 170 gsm and up to 300 gsm, it is referred to instead as coated art cardboard. Coated art paper consists of cellulose, sometimes with small amounts of wood, as well as fillers and binders. An additional varnish and a coating achieve a very smooth surface, which seals the colour and provides increased stability. At the same time, however, this also means that coated art paper is difficult to write on or stamp. On the other hand, the pure white paper, also known as art paper, does not absorb ink well, so that contours and colour boundaries appear particularly precise on this type of paper. This makes coated art paper predestined for the production of image prints with photo-realistic depth effects.

Preferred coated art paper is used for the following print media:

• books, notebooks
• brochures, flyers
• calendars, catalogues
• business cards, paper bags
• presentation folders, softcover envelopes

2. Offset paper

Offset paper is calendered, sized and often has no wood content. It is rewritable and printable, so it can be used for copiers, laser printers and inkjet printers. Offset paper is therefore indispensable for office use. In addition to its use as copy paper, it is also used for notepads and daily newspapers. Offset paper can also be written on well with ink, it does not fray and is highly resistant to picking. Furthermore, it feels authentically rough and has a noble and stable feel. The very high degree of whiteness makes the resulting print image shine. Offset paper is available in coated and uncoated form, is processed as sheets or from the roll and has a basis weight between 70 and 120 gsm.

Offset paper is mainly used for:

• Envelopes, stationery
• flyers, inside pages of brochures
• leaflets

Offset paper also exists as a cardboard and premium version with 120 and up to 300 gsm. This can also be used for flyers, but also for business cards, postcards and presentation folders.

3. Ecological paper types: Natural paper, recycled paper, environmental paper

Uncoated paper consists exclusively of natural fibres such as wood, coconut, hemp, flower petals, grains or grasses. It serves as an umbrella term that includes all multifunctional, normal and universal papers that have no synthetic fibres and have not been chemically treated. Natural paper is uncoated and the surface has not been refined. It can be used for many different applications, is easy to write on and achieves satisfactory presentation qualities. Images on this type of paper appear soft and warm, and a high colour intensity can be achieved. In addition, it has a pleasant feel, similar to that of art paper. Advertising material with a high proportion of text can also be presented in a high-quality manner on uncoated paper.

Uncoated paper is preferably used for:

• Newspapers, magazines
• Advertising journals, brochures, forms
• Drawing paper
• Paperbacks
• Legal forms

Modern digital printing in particular benefits from the use of uncoated paper, as powerful colours can be achieved. Likewise, the printing is odourless without solvents. Wood-free uncoated paper can also be used as watermark paper and bank post paper.

Recycled paper consists entirely of recycled and bleached waste paper, and there is no discernible difference between it and virgin fibre paper. However, it is also possible to deliberately highlight the difference, in which case the greyish version of recycled paper can be used. White recycled paper achieves outstanding colour reproduction, high print quality and smooth surface printing. It is used for the following printed materials:

• Brochures, stationery
• Catalogues, pads
• Business cards, registers
• Presentation folders

Environmental protection paper is also made from 100% recycled paper. Compared to recycled paper, it is more environmentally friendly because the waste paper is not bleached. As a result, environmental protection paper has a grey tone.

4. Volume paper and Ensocoat paper

Now that the "classics" among the paper types have been described, it is time for something more special. Volume paper is wood-free and has a matt surface similar to that of art paper. It has a weight of 160 gsm and is preferably used for book covers, as it makes the corresponding images appear vivid. Ensocoat paper is also free of wood and consists of a white chromosulphate board with a grammage of 276 gsm and a film lamination. These combinations make Ensocoat paper ideal for soft cover envelopes as they can be used to achieve outstanding print image reproduction.

5. Photo paper and postcard paper

Vivid colours and sharp details are achieved on photo paper. This ensures that the ink dries quickly after printing so that it does not smudge. Photo paper with a weight of 240 gsm is usually used for photo printing.

Postcard paper or postcard board is also characterised by its outstanding print quality and pin-sharp images. It has a single-sided, coated cardboard of 280 to 350 gsm and is a mixture of offset and coated art paper. Postcard paper effectively displays the printed image on the smooth front side, while the reverse side can be written on. In addition, this type of paper is very durable.

6. Fine cardboard and chromo cardboard

The ultra-fine board is a stronger type of paper with a grammage of 350 gsm. It is available in matt high white for brilliant colour prints as well as in matt cream for particularly noble results. Linen-textured fine cardboard is particularly suitable for greeting cards.

Chromo board weighs 320-450 gsm and is very robust. It is available in glossy white, matt grey or black. Chromo board can be used as cardboard for envelopes, for example, and it is also used for the back of spiral pads.

7. Linen paper and handmade paper

Linen paper has a high recognition value because it has a linen-like structure and is unique in its feel. Linen paper is very bright, but you should refrain from using large colour patches when printing. It can be used for business cards with 260 gsm as well as for exceptional envelopes with 100 gsm.

Handmade paper makes every print as noble as possible. It is also pleasantly flattering on the hand and can be used for business cards with 250 gsm.

8. Durable and robust paper types: Affiche paper, poster paper, synthetic paper

Affiche paper is also called blue-back paper and is UV-resistant and weatherproof. "Affiche" comes from the French and means something like "poster", "notice" or "placard". It has a grammage of 115 gsm and has a one-sided matt-coated, wood-free white front and a blue back (blueback). This is where the term blueback paper comes from. Poster paper can be optimally used for outdoor advertising: The blue back covers old posters optimally, even when the wet glueing method is used.

Poster paper in its classic form is matt-coated on the front, just like blue-back paper, so that the adhesive cannot penetrate it. It has a grammage of 150 gsm and is resistant to rain, moisture and UV radiation. Poster paper is preferably used when the printed image is to have a high dot and line sharpness.

Synthetic paper is characterised by a soft feel and simultaneous water and tear resistance. It is also resistant to scratches and withstands intensive use. This is why it is mainly used for menus in outdoor and indoor catering, as it achieves a rich colour effect.

Paper production today

The history of paper production began more than 2000 years ago. Paper is one of the most important inventions of mankind, because it enabled oral tradition to be passed on in writing and valuable cultural assets to be preserved. A large part of our knowledge today is recorded on paper, even though digitalisation continues to advance. Wood and water are among the main components in paper production, but nowadays there are also many other processes.

A brief digression: a historical look at paper production

Paper was invented in ancient China in 105 BC, when the Chinese Ts'ai Lun described the papermaking process as we know it today. First, fibres were pounded, then boiled and mixed with water. Silk waste, the remains of fishing nets, hemp, rags or even the bark and bast of the mulberry tree were used. The next step was to skim off individual layers with a sieve. The resulting layers of paper were then dried, pressed and finally smoothed.

In Europe, more precisely in Spain, paper was first produced in the 11th century with the help of water-driven paper mills. Nettle cloth as well as flax and hemp fibres, which were obtained from rags, were used. The producers of paper bought these from rag collectors. The paper was dried using the screw pressure of paper presses. From Spain, paper production spread continuously throughout Europe. In the 19th century, the existing processes were optimised and new innovative machines for paper production were developed. For the first time, chemical pulping of wood was used for fibre production, and the development of semi-synthetic and synthetic fibres was also undertaken. At the end of the 20th century, chlorine-free bleaching was integrated into paper production, which further improved the quality of the paper.

Raw materials used for paper production today

Paper production takes place in several steps, as the raw materials have to be prepared, processed and then specially treated. Depending on the type of paper being produced, it also has to be cut to size and packaged. There are now different paper machines that produce individual types of paper.

Water, wood or wood fibres and energy are the three main components of paper production. Water bodies such as lakes and rivers, hardwood and softwood forests serve as sources of these raw materials. The energy for the production process can be obtained by recycling production residues and waste from the manufacturing process, and using them as fuels. Depending on the type of paper being produced, different types of wood fibres are used, i.e. short fibres, long fibres and recycled fibres.

Preparation of the raw materials

The stock preparation of the various wood fibres also depends on which type of paper is to be obtained. Basically, the first step is to break down the wood into wood fibres, using either mechanical pulping to obtain mechanical pulp or chemical pulping to obtain chemical pulp. Mechanical pulping is also known as wood grinding, as the debarked pieces of wood are ground into wood fibres by a rotating grindstone. Alternatively, so-called wood chips can be defibrated by a refiner, in which thermomechanical wood pulp is produced by two rotating discs and the addition of pressure and heat. Chemical pulping pulp is obtained by using the sulphate process. In this process, the wood is boiled in a special lye and the binding agent lignin, which holds the wood fibres together, is removed.

After the stock preparation is complete, the wood pulp or cellulose obtained must be bleached. Bleaching is also subject to several steps in which impurities are removed and the desired degree of whiteness is to be achieved. Ozone, oxygen, chlorine, chlorine compounds or hydrogen peroxide in various forms are used for bleaching. The more environmentally friendly method of bleaching is done without the use of chlorine gas; instead, elemental chlorine-free or chlorine-free pulp is produced.

The production of paper using paper machines

Paper production also takes place in several steps. In the headbox of the paper machine, a fibre suspension is first injected between two running screens to form the paper webs. The fibre suspension consists of 99 % water and one percent fibres as well as other fillers. Then comes the wire section, where the excess water can run off to form a uniform paper web. In the press section of the paper machine, the next step is to reduce the water content from 80 to 50 % by running it through several rollers that press it out. This is followed by the drying section, where further liquid is removed from the paper by feeding it with hot steam. Finally, the last part is the rewind section. In this section, the finished paper web is rolled up into machine reels ("tambours") and transported to the finishing department. There the paper can be further treated depending on its future use, for example by surface sizing, smoothing, coating or super-calendering.