Meticulous flower and bird painting as a painting department, with the landscape, figure painting formed the art category of Chinese painting. In our country, we have a long history and excellent traditions. Through unremitting efforts and explorations by artists of all ages, the paintings of birds and flowers have formed a set of painting expression methods with oriental ethnic characteristics.
A good painting of fine flowers and birds can make people feel impressed and impressed. In order to obtain a good painting of flowers and birds, in addition to the selection of rice paper, silk, and pigment, we must pay attention to some problems in the screen printing process.
First , drawing negative film
Due to the large size of the meticulous flower and bird paintings, the quality of the photographic plate is good, but the cost is relatively high. Now we introduce several methods of hand-made film, which are both economical and practical.
Matte surface polyester film, 0.5 ~ 1.2mm thick. When using a thicker one, flat, difficult to warp, and good results. Before painting, scrub the terrazzo with talcum powder to remove the oil, then wipe the talcum powder and cover it with a clean fleece with the suede facing down. After the film is ready, the drawn draft paper is placed under the smooth surface of the polyester film and compacted.
Because the polyester film is slippery, it is not easy to stain the ink, sometimes it also loses ink color. This causes waste, and it is difficult to modify the draft and the effect is poor, which affects the quality of the printing plate. In order to trace high-quality manuscripts, neither ink nor ink, they have to work hard in Mexico to ensure the smooth development of the manuscripts.
Several methods of ink coloring are as follows:
1) Use a good soot block, add 1 to 2 drops of glycerin when grinding, and study it to a thick ink.
2) Take 150mL black ink, add about 8 ~ 10mL of formaldehyde, 3mL glycerol and mix thoroughly, let it naturally concentrated, if it is too concentrated can add appropriate amount of original ink thinning.
3) Use two bottles of drawing ink from Tianjin, add a tablespoon of sugar and a small spoonful of borax together into a beaker, put it on a simmer, and cook until the ink in the cup is reduced to about half.
4) Use a lot of detergent powder in Yideuge ink to grind to a thick ink and use it. This method writes awards and it is easy to get ink.
The motion picture pen should be drawn according to the intention of the manuscript. Do not behave rashly or change it. Take it seriously. Otherwise, the underlying film will be dirty.
The painted polyester manuscript can be used directly if it is used once. If it is used multiple times, it must be sprayed with varnish thinly and then dried and used. It can also be sprayed with kerosene for the purpose of increasing its transparency, but the durability of kerosene is poor.
A small amount of available glass, choose a glass of the same size as the manuscript, use a washing powder, shoe brush to rotate and grind the two sides, rinse it, dry it slightly, wipe it with a little white water, and paint it after drying. After the manuscript is finished, spray varnish again and use it after drying it.
Can also use cellophane (celluloid) rendering. The cellophane is thin and does not have to wrinkle when it is used. After painting, you can use kerosene once. The red tear film is used to make the bottom plate. First, the manuscript and the red tear film are fixed, and the line is cut with a knife. The line is left and the excess is removed. The advantage of red tear film is that it is suitable for making negative images, and the effect is quite good.
The film base of the manuscript is relatively soft and must use a thin glass with high transparency and no water ripples of 3 to 5mm. Stick four corners with tape, do not scratch the book, flatten, set the rules, you can print.
Some of the original manuscripts are to be reused. After the silk screen version is printed, the manuscripts are removed and wrapped in airy, burr paper. The next time they are used.
Second, stretch net, glue, printing plate, scraper, printing material
The stretch net first selects small red, white pine or dried paulownia trees, preferably fir. Saw a wood strip with a width of 40mm and a height of about 30mm, and open a groove of 8mm in depth and 5mm in width at the 2/3 part of the wood strip, fix the wood strip with a rake and a rake, or nail it into a frame with a corner iron. The four corners are 90 degrees, and the size depends on the requirements. The in-frame size is approximately 60mm larger than the four sides of the screen.
When stretching the net, first grab the corners of the soaked and soft wire mesh with both hands, shake the water, and put it on the net frame to find a good position. The cable should be horizontal and vertical, first use a small nail to nail the four corners, and then nail it in the middle. Do not push the nails to the end. After flattening, the square bar with the same width and width as the frame slot will be set in the slot. The weft and back warp will slow down. Slow inset. When the edges are flat, the wood strips are plunged into the grooves, so that the tension is even and the printing is not easy to deform. Then the small nails outside the grooves are pulled out, the excess wire mesh is cut off with a flat spatula or a knife, washed with water and dried for use.
Under normal circumstances, the net has to be stretched in advance and placed for one or two days. The purpose is to relax the screen and avoid cracking after gluing. Special attention should be paid to the fact that the latitude and longitude lines at the time of stretching must be perpendicular to each other so that jaggies can be avoided and printing quality can be guaranteed.
It is also possible to stretch the net diagonally. This method is suitable for the printing of circular screens with little distortion. The stretched frame must be treated with aging so that the tension is even and it can improve the resistance and precision.
Stretch the frame and rinse it with clean water. Then put it in the aqueous alkaline solution to degrease and remove the fingerprint. At the same time, the screen has also been roughened to increase the bonding strength. It is better to use imported grinding sizing, but the price is higher.
The formula of the aqueous alkali solution is as follows:
Water 1000mL
Caustic Soda 15g
Potassium dichromate 1～2g
The frame is soaked in alkaline water for 30-40 minutes. After removal, it is flushed with water, preferably with a high-pressure spray gun. Rinse the net frame and dry the moisture, put it in an oven, and dry it at 45°C or blow it off with a hot air blower. The screen must be scrubbed, otherwise it will be yellow after drying and will affect the printing effect.
There are many kinds of silk screens such as polyester and silk. There are two kinds of white and yellow color. The finest mesh is 750 mesh (imported from Italy), the thickest 80 mesh. There are two types of silk yarns, round yarn and flat yarn. The flat wire mesh imported from Japan can be scraped after being stretched. It is very convenient to use.
Available domestic DH diazo photosensitive plate, the formula is as follows:
DH diazo sensitive emulsion 1000mL
Photosensitizer 10g
Water about 150 to 200 mL
When dispensing the glue, first dip the used azo photosensitive emulsion into a brown-red bottle, fill the cup with 140 mL of water, pour the photosensitizer 10 g into the measuring cup, stir it with a glass rod, fully dissolve it, and use 200 mesh. Mesh filter, mixed with the glue, brush the measuring cup with the remaining water, and pour into the glue at the same time to ensure the precise proportion of the formula. The glue should be thoroughly mixed and kept still for 24 hours (hours). After the bubbles are eliminated, the glue can be applied. 140 mL of water in the summer and 200 mL of water in the winter.
Before gluing, cool the oven frame for a while and check it carefully. If you touch it smoothly, there is no sundries and you can sew. Be careful not to touch it in the summer, because perspiration may affect the appearance of the image, or it may not stick to the adhesive, so care should be taken.
One-component photosensitive adhesives have the type SBQ-XL solvent-resistant photosensitive adhesive, SBQ-ER water-resistant photosensitive adhesive produced by Murakami Corporation, which is easy to use, but the price is more expensive.
Glue can be used for special gluing device, can also be used plexiglass triangle plate instead.
When the glue is used to glue the glue, the photosensitive glue is poured into about 1â„3 of the volume in the glue applicator, and a different glue applicator can be selected depending on the size of the net frame. First put the frame at an angle of 85° and put it firmly. The gluing device should be flat. From the bottom up, scrape 1 to 2 times of glue on the front side and scrape it 1 time on the reverse side. Check for leaks and dry them with an oven or blow with a hot air blower. Pay attention to about 30cm away from the layout when the hot air is blown, swing back and forth in an orderly manner, and completely dry it until it is completely covered with a black velvet cloth. The above operation should be performed under a red light in a dark room.
When using the triangle scraper, first pour the glue on the front side of the net frame, then slowly scrape and straighten it with the triangle, and then scrape it and dry it. The temperature is maintained at 30-45°C to avoid overheating of the glue and to form heat crosslinks. The film cannot be removed during development.
The dried screen plate is placed on a flat glass plate with the concave surface facing upwards, and the lower surface is covered with black velveteen or red velveteen cloth and clamped with clips. Then put the glass with the bottom plate on the screen plate, clamp the glass with the deep mouth clip, and print it under the printing light box for 3~5min. The distance between the iodine tungsten lamp should be kept away from the layout of 40 ~ 50cm or so, to avoid overheating, development does not penetrate the net. UV cold light should be closer to the distance, printing about 5min. Ultraviolet light is harmful to the human body. It takes a long time for the eyes to see that the object is green, and it should be avoided to observe it with the eyes for a long time. Conditional wear safety glasses. Vacuum printing machine can also be used to print, in short, depending on the conditions.
After the exposure of the screen into warm water in the development of 2 ~ 3min, the water temperature of about 30 °C. After the powder is developed, the two corners of the side are grasped and gently vibrated up and down. The pattern gradually appears. The part that covers the light begins to fall off and forms a stencil. With a high-pressure spray gun sprayed from the opposite side first, the distance is 30cm, and all the patterns are transparent. Then spray from the front, exposing a white breathable mesh, check the pattern against the sun, so far. Do not spray too much. Long spraying will affect the accuracy of the edges of the pattern. Then spin off the water, or use a new towel to dry the water, do not rub it. Only press it up and down, put it in the oven, and dry it in the summer. After drying, the screen is filled with sand, holes, etc. with the original photosensitive adhesive, and then baked for 10 minutes to fully crosslink it. It can also be re-exposed for 10 minutes. Brush on a hardener and let it dry. The purpose is to increase the resistance to printing.
The squeegee can be made by itself, and a piece of rubber strip 0.8 to 1 cm thick is used to cut a piece according to the need, and then a groove of 2 cm thick wood is used to insert the rubber strip into the groove. The edge of the plane shaved into two sides or one side of the slope, leaving 2 ~ 3mm in the middle. Grab the surface into a semi-circle, not to rise hands.
Scrapers can also be purchased ready-made, soft, hard, long, short. The round mouth is suitable for printing rubber and has a large amount of ink. The disadvantage is that it is not suitable for printing fine. The oblique mouth is suitable for printing metallic ink and is printed thin. The tip is suitable for printing paper, and the flat mouth is suitable for fabrics, etc., and can be flexibly used according to the purpose.
The printing materials used for printing pens, flowers, and bird paintings can be modulated with cherry blossom paste, fine white powder, Huabiao white latex and Yidege ink. The formula is as follows:
Cherry brand paste: A bottle of about 500g
Titanium dioxide 10g
Huabiao White Latex 25g
Yidege Ink 20mL
The prepared printing material is stationary for 4 hours, covered with a plastic film and not crusted.
When printing the lines, do not print too dark, the ink is too stiff and rigid, the effect is not good, and it is not easy to complement the line.
The color paste can be used during the printing process, and the white paste is added in proper amount in the black color to make it clear and ink-like.
In order to print the linework, the paper and paperboard are cut according to the design requirements, using boards or glass that are slightly larger than paper or cardboard. Flatten the paper and file, stick it with tape, flatten it by hand, and paste it with another tape.
The printing material preparation during printing is very critical, so as to prevent the infiltration and running of ink during the installation, and it is even more difficult to handle.