Envelope. An envelope is a common packaging item, usually made of thin, flat material.
It is designed to contain a flat object, such as a letter or card. Traditional envelopes are made from sheets of paper cut to one of three shapes: a rhombus, a short-arm cross or a kite.
These shapes allow the envelope structure to be made by folding the sheet sides around a central rectangular area. In this manner, a rectangle-faced enclosure is formed with an arrangement of four flaps on the reverse side.
Patent drawing of Americus Callahan's windowed envelope A folding sequence such that the last flap closed is on a short side is referred to in commercial envelope manufacture as a pocket-a format frequently employed in the packaging of small quantities of seeds. Although in principle the flaps can be held in place by securing the topmost flap at a single point, generally they are pasted or gummed together at the overlaps.
They are most commonly used for enclosing and sending mail through a prepaid-postage postal system. Window envelopes have a hole cut in the front side that allows the paper within to be seen. They are generally arranged so that the receiving address printed on the letter is visible, saving duplication of the address on the envelope itself. The window is normally covered with a transparent or translucent film to protect the letter inside, as was first designed by Americus F. Callaha
It is designed to contain a flat object, such as a letter or card. Traditional envelopes are made from sheets of paper cut to one of three shapes: a rhombus, a short-arm cross or a kite.
These shapes allow the envelope structure to be made by folding the sheet sides around a central rectangular area. In this manner, a rectangle-faced enclosure is formed with an arrangement of four flaps on the reverse side.
Patent drawing of Americus Callahan's windowed envelope A folding sequence such that the last flap closed is on a short side is referred to in commercial envelope manufacture as a pocket-a format frequently employed in the packaging of small quantities of seeds. Although in principle the flaps can be held in place by securing the topmost flap at a single point, generally they are pasted or gummed together at the overlaps.
They are most commonly used for enclosing and sending mail through a prepaid-postage postal system. Window envelopes have a hole cut in the front side that allows the paper within to be seen. They are generally arranged so that the receiving address printed on the letter is visible, saving duplication of the address on the envelope itself. The window is normally covered with a transparent or translucent film to protect the letter inside, as was first designed by Americus F. Callaha
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