What color ink is the blue-black ink bag?

The difference between blue-black ink sac and dark blue ink sac;

1, different colors

Blue-black ink bag and dark blue ink are both fountain pen inks. The color of blue-black ink is blue, and dark blue ink is black.

2. The ingredients are obviously different.

Blue-black ink composition Acid ink The dye ink made of blue is single in composition, smooth and non-sticky, and its color is blue-black, which belongs to acid ink. The components of dark blue ink are tannic acid (C4H 10O9), gallic acid (C7H6O5 H2O) and ferrous sulfate (FeSO4), which combine with each other to form ferrous tannic acid and ferrous gallate, which are insoluble after oxidation.

3. The picture on paper has different storage durability.

Blue-black ink is composed of components that will not fade after blackening, pigment components, stabilizers, corrosion inhibitors, wetting agents, preservatives, etc., and there are many impurities, so it is not suitable for multi-use. Mildew is easy to grow in humid environment, and it may stick to the pen after long-term use, and the writing color is blue and black. The main purpose of adding stabilizer to dark blue ink is to eliminate the precipitation of ink and avoid the phenomenon of water shortage when writing.

Extended data

About blue and black ink

1, and the composition of the pigment is:

At present, acid ink blue and direct lake blue dyes are commonly used. Black water blue is the main color of ink, and the aqueous solution does not deteriorate in acid, but turns brown in alkali. Direct lake blue plays an auxiliary role in ink, because it contains more impurities, so it is not suitable for multi-use, and it is easy to grow mildew in wet environment.

2. Stabilizer:

The main purpose of adding stabilizer to ink is to eliminate the precipitation of ink and avoid the phenomenon of water shortage when writing. Commonly used stabilizers are sulfuric acid (H2SO4), oxalic acid (hoocooh) 2 and formaldehyde (HCHO) solution. These stabilizers have certain acidity, which lays a hidden danger for paper acidification and should not be used more.

3. boycott:

Because the stabilizer added in ink has strong acidity, in order to prevent corrosion, a corrosion inhibitor is often added to form a film with iron to reduce the corrosion effect of sulfuric acid by 90%. The iron content in the ink will not increase due to the corrosion of the pen tip, thus increasing the stability of the ink.

4. Wetting agent:

In order to prevent the water in the ink from evaporating, which makes writing inconvenient, glycerol [C3H5 (OH) 3] which is non-volatile and absorbent is added to the ink to keep the nib moist and facilitate writing.

About ink sac

1, ink bag is a tube filled with ink, which can be used by directly inserting a pen and covering it. It is disposable and usually contains a bead to prevent ink from overflowing. Although the effect is better, the cost performance is not particularly high.

2. Please discard the ink in the ink bag after using it. In addition, similar products also have ink absorbers, which can be used repeatedly like ordinary pens.

References:

Baidu encyclopedia-blue and black ink

References:

Baidu encyclopedia-ink sac