Information about the envelope
1. Envelope specifications:
The standard envelope specifications are (length × width on the front):
Envelope No. 3 (B6): 176×125mm
Envelope No. 5 (DL): 220×110mm
Envelope No. 6 (ZL): 230×120mm
Envelope No. 7 (C5): 229×162mm
Envelope No. 9 (C4): 324×229mm
Because this form of the envelope is widely used in production and life, it is not only used to hold letters. Paper bags such as red envelope bags, CD bags, button bags, and glasses bags, as well as many forms exported abroad, are non-standard.
2, envelope style:
Chinese envelope: short side opening;
Western-style envelope: long side opening;
Diamond-shaped envelope: mainly used to hold greeting cards;
Portfolio: there is a 2-4cm wall on the side;
Window envelopes: such as bank statement envelopes, CD bags, etc.;
Special computer envelopes: mainly to facilitate machine identification, make some corresponding round holes in the envelope, and so on.
3. Envelope sealing form:
Envelope without glue seal: the common form of domestic envelopes;
Saliva glue-sealed envelope: A common form of foreign envelopes, with saliva glue on the seal;
Self-adhesive sealed envelope: self-adhesive is applied to the seal;
Self-adhesive-sealed envelopes (release paper envelopes): The seal is coated with self-adhesive and release paper is pasted.
4, envelope paper:
Generally, 80g-150g double offset paper and kraft paper (natural kraft paper, white kraft paper) are used. According to different functions, art paper, art paper, etc. are also used.
The operation of the envelope machine requires that the paper must have high tensile strength and tearing degree to avoid paper breaking and cracking. The best match with offset paper is because the offset paper absorbs ink.
The origin of the envelope
Envelopes are commonly used things for each of us. So, when did the envelope start to be used?
The envelope originated in the Qin and Han dynasties more than two thousand years ago. At that time, documents and letters were mostly carved on wooden boards and bamboo slips. In order to protect the integrity of the letters, two wooden boards carved into a carp shape were sandwiched on the outside of the paper slips. There are also three wire grooves engraved on the board, which are tied with rope three times, and then pass through a square hole to tie it. Check the wood at the end of the line or at the intersection, seal the clay and affix a seal to prevent unauthorized demolition. This is the earliest envelope in history.
From the Wei and Jin Dynasties to the Northern and Southern Dynasties, letter materials gradually evolved from wood to paper. The envelope was changed to be made of two pieces of thick blue paper, but there were carp pictures on both sides, so it was naturally no longer sealed with mud. Now the envelopes are more exquisite. They are no longer ordinary white and kraft paper colors. They are also made in many other colors.