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Encyclopedia of printing: trace the development history of envelope printing

envelopes are necessary for our daily letter writing, but how many people know about the history of envelope printing. This article makes a digital display of the history of envelope printing. With the improvement and design of the chemical properties of polymers, the electronic experimental machine is suitable for users who only seek force value, tensile strength, compressive strength and other relevant data, so that everyone can know more about the development mileage of envelope printing

1. Postage envelope

postage envelope is to seal stamps and letters together. Postage envelopes have the same value as stamps

postage envelope printing: it is also divided into several types, such as ordinary postage envelope, Art Postage envelope, commemorative postage envelope, airmail postage envelope, etc., which refers specifically to commemorative postage envelope

(1) commemorative postage envelope printing (JF)

this kind of stamp cover is specially issued to commemorate an important historical event, important organization, etc. the postage pattern in the upper right corner and the pattern on the left side are well designed, complement each other, and are printed in color, which is very exquisite. If a postage envelope is equivalent to a stamp, then a commemorative postage envelope is equivalent to a commemorative stamp in the stamp family

(2) ordinary postage envelope printing (PF)

the difference between this ordinary postage cover and the commemorative postage cover is that this ordinary postage cover prints the issued ordinary stamps as the postage pattern, and there is generally no other pattern on the envelope except the postage figure

(3) Art Postage envelope printing (m)

according to the explanation that has been accepted by the public, this is an envelope printed with art patterns and postage maps, that is, its postage patterns, is a kind of thematic art patterns

2. First day cover

on the first day of the official issuance of the stamps, the set of stamps is pasted and stamped with the postal date stamp of that day. The envelope actually mailed and delivered by the post office is the first day cover. With the wear and tear of valves and oil cylinders in philatelic activities, the first seal has evolved into a separate type of stamp products

the first head office first day cover of the special prefix stamp was special 18 "children" issued on June 1st, 1958, priced at 34 yuan in 1990. The first day cover of the last special prefix stamp is also the last set of special prefix stamps, that is, special 75 "women in the service industry" issued on May 10, 1966, priced at 78 yuan in 1990

3. Real envelope

all envelopes actually posted and delivered by the postal department, including postcards, postmen, etc., are called real envelope. The value of the real envelope lies in that it has important historical significance for the study of stamp issue date, postal history, etc

4. In place seal

the so-called in place seal refers to the actual seal sent on the first day of the place related to the new mail theme or main map

5. The commemorative cover

is specially designed, printed or drawn by the postal department or other units and individuals to commemorate any commemorative event. The friction speed between the brake disc and the brake pad when the current stamp is affixed is 60 ⑺ 0m/s. The envelope stamped with the relevant postal date stamp or commemorative postmark can be included in the scope of commemoration

6. Inlaid cover

internationally, a kind of first day cover or commemorative cover with coins or other metal commemorative medallions embedded in envelopes is popular, which is called postal money cover. China has created inlaid seals on the basis of postal money seals, that is, in addition to inlaying coins and metal commemorative medals, porcelain or plastic stereoscopic paintings and commemorative medals can also be inlaid