The density of whatman paper or printing paper is very important. This criterion determines their scope of use, print quality and even the longevity of the printer. What is the density of different types of paper, and how to choose the right one for a particular type of work?
Density and thickness are not the same thing.
Speaking of density, many mean the thickness of the paper, but this is a mistake. A thicker sheet of paper of one brand seems to be more dense than another, while their density indicators can be identical.
In fact, thicker paper is more loose and porous, it is more prone to wear and has a shorter service life. Whereas a thin one with a higher density is more compressed and will last longer. And the ink on it lies more evenly, which is the key to a clear high-quality printing. Therefore, thin paper can not always be bad.
What paper is used where?
In various fields, paper of various densities is used. For example, printing requires indicators from 60 to 300 g / m 2 . This figure is much lower for newsprint - only 45-60 g / m 2 . Drawing paper or watercolor, paper for letters and business cards - all these are certain varieties with a specific density, the criteria for which are strictly regulated. And whatman even has clear indicators fixed in GOST.
Speaking about whatman, it is worth noting that this is the largest paper format used in the field of design and art. It is very popular among people of various professions.
Density and print quality
Paper weight and printing specifications are closely related. In the instructions for each printer, the manufacturer usually indicates the format and recommended density. A4 marking, 64-163 g / m 2 , for example, means that such paper is suitable for this device. Whatman paper with a density higher than acceptable will not work - it can even damage the mechanism and damage the printer.
Typically, standard office printers and copiers use A3 and A4 paper with an average density of 80 g / m 2 . It is these indicators that manufacturers are guided by releasing printing paper. Each of them produces its own brand, with a guarantee of high quality printing on paper of this brand. For example, products of the domestic brand “Snegurochka” are very popular in our offices.
Paper weight and GOST indicators
If the density is known, then the weight of a sheet of paper is also easy to determine. For example, an A4 sheet with numbers on a package of 80 g / m2 will weigh almost 5 grams. In a standard pack of such paper, 500 sheets, which means that the weight of the pack will be about 2.5 kilograms. If the actual weight exceeds this indicator, most likely, storage conditions were not met, and the level of humidity of the paper is above normal.
Paper for office printing, books and letterhead, with a density of 160 g / m², will have indicators from 800 to 900 kg per cubic meter. Less than 160 - from 750 to 850 kg / m³ In addition to offset paper, paper is also popular. The GOST density sets for it at the level of 850–950 kg / m³. Newsprint has the lowest density - it is also the most inexpensive. The term of its “life” is only a few days, after which the manufacturer cannot guarantee wear resistance: such paper begins to crumble and turn yellow.
Depending on the printing task, the density as well as the stiffness and thickness of the paper may vary. Today, there are different standards, and to select all the criteria individually is not difficult.
Whatman - premium paper
Whatman's density is higher than other types of paper, so it is considered first-class products. There are several standard formats: from A1 to A4 (you can also find a Whatman paper in A5 format), each of them has its own density - ranging from 120 to 200 g / m². And there is A0 paper with impressive sheet parameters of 841x1189 cm. This Whatman paper will be larger in size than all other formats combined.
In addition to such indicators as the weight and density of whatman paper, the homogeneity of the paper pulp is also important, which improves print quality. And the high opacity of the sheet allows you to print or draw on it from both sides.
How to determine that this is a real quality whatman? First of all, in appearance: this paper is white, dense and smooth. If in doubt, drop a little clean water on a leaf. Drawing paper should not be deformed from it. It is this that is used not only for drawing, but also for drawing - with paints, ink or a pencil. Although for these purposes, professional artists often buy special watercolor paper, with a high density and excellent moisture absorption.
Where and how much to buy whatman paper?
So, you know what tasks you need this paper for, you know what the density of the paper should be, but where to buy it? Typically, at a stationery store or bookstore. Whatman paper is sold at an affordable price - for a sheet of A1 format you will need to pay no more than 20 rubles. Smaller sheets will cost you even less.