drawing printing , commonly known as "blueprint paper" , is a kind of chemical coating processing paper, specially used for printing drawings in various engineering designs and machinery manufacturing. It is an indispensable supply in production, scientific research and construction.
Blue architectural engineering drawings are a mass drawing method developed in the era before computer drawing.
The draftsman used a carbon pen to draw the picture on a transparent paper named " sulfuric acid paper ". The purpose is to facilitate the use of " printing machine " to print a large number of identical drawings when a large number of drawings are used in the future. The blue color on the
drawing is due to the working principle of ammonia fixation photosensitivity of the "printing machine" and has no other meaning.
At present, drafters can use CAD to complete the drawing of various structural drawings instead of hand drawing. At the same time, when drawing, they can use a large plotter shaped like a printer to print the drawings in the computer on white drawings. It can also be printed in color.
However, in order to copy the same drawing in large quantities, designers are still using the past "picture sharing method". The drawing cost of is very low. The cost of printing an A1 size drawing into a blueprint is about 0.80 yuan. And it is very efficient. It only takes a few seconds to print an A1-sized drawing into a blueprint. If you don't want the
drawing to be too blue, you can slow down the time it takes to post it; conversely, if you speed up the time it takes to post it, it will become bluer.
Printing machine
Blueprint paper (blueprint yaper) is also called printing paper , diazo salt is like printing paper or diazo photosensitive paper. A kind of processed paper made by using blueprint base paper as the paper base, and then coating the dry base paper with photosensitive agent. It is roll paper.
base paper is required to have good wet tensile strength and absorption properties, minimal wet deformation, and does not contain chemicals that affect the performance of sensitive materials. It is usually made from cotton pulp or bleached wood pulp on a paper machine. Blueprint paper made from qualified base paper has the characteristics of smooth paper surface, uniform photosensitive layer coating, and no white spots, spots, chemical stains, wrinkles, etc.
The use methods of drying drawings are divided into:
1. Wet drying drawings, that is, water-washed drawings, also known as iron-salt drawings. The photoreduction method is washed with water, and some units still use this method.
2. Dry printing drawings, that is, diazo additive drying drawings, or ammonia fumigation drying drawings. The photoreduction system uses ammonia gas. This kind of drying drawings are supplied in China.
3. There are two types of semi-wet printing methods. One is to apply photosensitive agent and reducing agent on the paper, and the photo is combined to form a picture at the same time. This is not available in China; the other is for dry printing, in which ammonia is evaporated during printing. It forms a mist so that it can be photographed while drying. From the line color,
is divided into:
1, blue line on white background, white line on blue background, brown line on white background, and wet drying drawing.
2, purple lines on blue background, brown lines on white background, black lines on white background, are dry-printed drawings. in China currently mostly has purple lines on a blue background, and some areas have blue lines or black lines on a white background.
From the coating surface: there are two types: single-sided coating and double-sided coating:
1. Single-sided coating has two meanings: one is to only apply photosensitive liquid on the paper used; the other One side is coated with photosensitive agent and the other side is coated with boric acid water to eliminate the warpage of the paper and improve the storage period. It is actually coated on both sides. Since only one side is photosensitive, it is also called single-sided coated shoes. This is the case in most parts of the country. one type.
2. Double-sided coating is to apply photosensitive agent on both sides, and pictures can be printed on both sides. The main purpose is to reduce the volume of data and save paper. At present, there are 19 places in China that produce printing drawings, including Shanghai, Beijing, Tianjin, Hangzhou, Nanjing, and Wuhan. The development direction in recent years is white background with blue lines and double-sided coating, because the blue line printing drawings will not change during storage time. Below, the photosensitive speed is 1/5 faster than the purple line, and the color is bright, and the photosensitive speed tolerance is large.
