Blotting Paper: Meaning, Application & Water Absorption Test

by Universal Engineering Corporation Suppliers Of Precision Testing Instruments in Saha

So what actually is blotting paper?

Blotting paper or bibulous paper is an extremely absorbent paper, used to absorb the excess liquid substance such as ink or oil from the surface of writing paper. It is made from varied materials of different thicknesses, smoothness, etc. based on the varied applications. However, most blotting papers are made of cotton and manufactured on paper machines. Since they are unsized papers unlike normal papers, the water absorption tester is used to determine their water absorbency. This instrument uses Klemm Method to perform the test.

But before we know more about the absorbency test of blotting paper, let us throw some light on its several applications in the following section.

Application Of Blotting Paper

Due to its ability to absorb excess liquid, blotting paper has several applications.

Cosmetics

Bibulous paper is used to remove excess oil or makeup from the face skin. To be used in the cosmetic industry, these papers are first dyed and then dusted with salicylic acid and minerals. This is done to make it capable of preventing acne breakouts.

Writing

In the writing domain, blotting becomes essential when dip pens are used. Sometimes fountain pens also call the use of blotting paper. When blotting paper is used to remove ink from writings, the impression comes in reverse on it.

Art

Watercolor paper is a form of blotting paper. It is produced due to its absorbent perks, as this allows better water and pigment absorption than other drawing papers. There is a very less difference between watercolor paper and blotting paper, however, the process of making each is different.

Chemicals

When it comes to chemicals, blotting paper finds application in chemical analysis as a static phase in thin-layer chromatography. Besides, it is used in measuring the pH balance of swimming pools or spas. Here, disposable plastic strips are attached to small pieces of blotting paper. They are then soaked in the water with pH-sensitive compounds extracted from lichens, for measurement.

Water Absorption Test

Now that we know about the various applications of blotting paper, let us now understand how these papers are tested using a water absorption tester before actually being used.

The testing instrument determines the capillary rise in the blotting paper. Capillary rise refers to the phenomenon of rising of the liquid surface in comparison to the normal liquid level.

This capillarity rise of water takes place in the test specimen strips.
For testing, a specimen strip is placed, with its lower end, vertically immersed in a vessel filled with water.
This strip is then removed from the water, after which the water that has been absorbed and risen in the specimen is read from the scale, and the time is also noted.

The same method is used to measure the absorption characteristics of inks, oils, and other liquids.

Conclusion

UEC is a leading paper testing equipment supplier, standing in the market for many decades. From paper to pulp to board and packaging, we have quality control instruments for each of them. Get in touch with us to share your requirements.