What does it mean to have H and B printed on the pencil

The amount of lead in the pencil.

"h" is the first letter of the English "hard", which indicates the hardness of the pencil lead, and the larger the number in front of it, the harder the lead core and the lighter the color. “b"It's "black" in English"The initials of (black) represent the composition of graphite, indicating the softness of the pencil core and the degree of visibility of the writing, and the larger the number in front of it, the thicker and darker the color.

Generally, "H" is used for hard pencils, "B" for soft pencils, "HB" for pencils with moderate hardness and softness, and "F" for pencils with a hardness between HB and H. Graphite pencils are divided into 18 hardness levels, such as 6b, 5b, 4b, 3b, 2b, b, hb, f, h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, etc., the larger the number in front of the letter, the harder or softer it is. In addition, there are 3 grades of soft pencils 7B, 8B, and 9B to meet special needs such as painting.

But now it seems that there are still 12b pencils, and it feels almost like charcoal.

H is the first letter of the English hard (hard), indicating the hardness of the pencil lead, the larger the number in front of H, indicating that the lead core is harder and the lighter the color. B is the first letter of black in English, indicating the composition of graphite, indicating the softness of the pencil core and the obvious degree of writing, and the larger the number in front of B, the stronger and darker the color.

The full name of HB is: Hardness Black means pencil with hardness or gray scale in the middle (slightly blacker).

b--black

h--hardness, the more hardness b number, the darker and softer the pencil, and the more h number, the harder and lighter the color. HB is intermediate. The HB pencil is suitable for writing, while the B pencil is suitable for drawing, and the H pencil is suitable for making marks on hard objects.

The full name of CD is: Compact Disc refers to laser discography.

The full name of the BBC is: British Broadcasting Corporation refers to the British Broadcasting Corporation.

The British Broadcasting Corporation (BBC) for short.

Founded in 1922, it is the largest news broadcaster in the UK and one of the largest in the world.

Although the BBC is a public institution that receives financial support from the United Kingdom, it is managed by a 12-member regulatory committee independent of the United Kingdom, and its independence is guaranteed by a royal charter.

The Governing Council administers the BBC as a trustee in the public interest, and they are all prominent members of the community, including the Heads of Scotland, Wales, Northern Ireland and England, nominated by the Prime Minister of the United Kingdom and appointed by the Queen of England.

H and B are the hardness symbols on the barrel of the pencil, H represents the hard pencil, and the larger the number in front of it, the greater the hardness; b stands for soft pencil, and the larger the number in front, the softer the refill. hb stands for pencil with moderate hardness and softness, which is suitable for everyday writing.

The higher the h-value, the harder and lighter the lead core; The higher the b-value, the softer the lead core and the darker the color. Both Hb and F indicate medium, with Hb belonging to Nakamori and other slightly darker (commonly used) and F belonging to medium to slightly hard (rare).

b--blackBlackness

h--hardHardness cavity hunger

1. The hardness mark of the pencil and lead core is generally used"h"Indicates a hard pencil"b"Indicates a soft pencil"hb"It means that the hardness and softness are moderateof pencils,"f"Indicates a pencil with a hardness between Hb and H

2. The larger the number in front of H, the harder the lead core and the lighter the color.

3. The larger the number in front of B, the softer the lead core and the darker the color.

4. Arrangement (From soft to hard9b, 8b, 7b, 6b, 5b, 4b, 3b, 2b, b, hb, f, h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h and other hardness and other side circle search grades.

Use caution

1. Are pencil leads toxic? In fact, pencil leads are not poisonous. Lead is poisonous, and the main raw materials for making pencil leads are graphite and clay, which of course is not poisonous.

The main components of the pencil refill are graphite and clay, graphite is a solid with a metallic luster in the form of scales, which has carbon-carbon chemical bonds, between the layers is van der Waals force, carbon-carbon chemical bonds are very stable, it is very difficult to break, which is why diamond and graphite are composed of carbon, but the physical properties are very different from **, there is nothing in the human body that can destroy the carbon-carbon chemical bonds, so it is certain that the pencil lead is safe (unless the clay added inside is harmful to human health).

2. Is the pencil barrel metal poisonous?

The appearance of the pencil barrel has a wrapping mold or the use of pencil paint technology, on the one hand, it can protect the pen barrel, on the other hand, it can increase the appearance, but the pigment will contain trace heavy metals, and a small amount of contact will not be affected, but it is not appropriate to bite the pen barrel to eat in the mouth.

H and B are the hardness symbols on the barrel of the pencil, H represents the hard pencil, and the larger the number in front of it, the greater the hardness; B stands for soft pencil, and the larger the number in front of it, the softer the refill. hb stands for pencil with moderate hardness and softness, which is suitable for everyday writing.

The larger the h value, the harder the lead core will be, and the lighter the color; The higher the b-value, the softer the lead core and the darker the color.

Both Hb and F indicate moderate, with Hb being moderately slightly darker (common) and F being moderately slightly hard (rare). The higher the number in front of h, the harder the lead core and the lighter the color. The higher the number in front of b, the darker and darker the color.

The classification of pencil shafts is based on the amount of graphite in the refill. Among them, Class H pencils have relatively high refill hardness and are suitable for objects with relatively hard or clear interfaces, such as woodworking scribing, field drawing, etc.; The refill of HB pencil has moderate hardness, which is suitable for writing under general circumstances, or for playing mountain trapping outlines; Type B pencils with relatively soft refills are suitable for drawing and can also be used to fill in some machine-recognizable cards. For example, we often use a 2B pencil to fill out answer sheets.

The h and b printed on the pencil are the hardness markers of the pencil core. Generally, "H" is used for hard pencils, "B" for soft pencils, "HB" for pencils with moderate hardness and softness, and "F" for pencils with a hardness between HB and H. The higher the number in front of h, the harder the lead core and the lighter the color.

The higher the number in front of b, the softer the lead core and the darker the color.

H class pencil, pencil refill hardness, more suitable for woodworking line drawing, drawing, etc., while writing is recommended to use Hb type, scribbling answer sheets, painting and other recommended use B pencil.

The pencil barrel is sold simply and burning, and the appearance has a wrapping mold or pencil paint technology, which can protect the pen barrel on the one hand, and increase the appearance on the other hand, but the pigment will contain trace amounts of heavy metals, and a small amount of contact will not have an impact, but it is still harmful to bite the pen barrel and eat it in the mouth.

In painting, the B-type pencil has a moderate lead quality and is suitable for sketching, and it is sometimes used for white drawing, and the H-type lead is harder and suitable for white drawing, but because of its hard lead, it is rarely used. Carbon lead and carbon strip sketches are also commonly used in paintings.