Which is perfect for printing text or images with fine details. As a result of the work, you will have developed unique prints on fabric, clothing, paper that were made with your own hands.
After stretching the fine mesh fabric onto a wooden frame, apply a thin layer of photosensitive emulsion to the screen and allow it to dry. Then take a stencil (transparency film with images printed on it) and place it on the screen, then expose the “screen and stencil sandwich” to light. Light helps strengthen the emulsion and binds it to the tissue. Where light is blocked by the stencil images, the emulsion remains water-soluble.
Next, we direct a stream of water onto the screen, washing away the unhardened emulsion. These areas will cause ink to bleed onto the fabric during printing. Finally put it on a T-shirt or other fabric (paper), apply ink to part of the screen. If you are using fabric paints, you can heat them after they are dry and the image will be permanent and washable.
We follow the instructions that are written on the cans of photographic emulsion.
Fill the bottle with the sensitizer 3/4 full with cold water. Shake the bottle well. Sensitizer (in the form of sediment at the bottom of the bottle), vigorous shaking is required for mixing.
Pour the contents of the bottle into a container with photo emulsion. Mix everything until the color is uniform. The initial color of the emulsion is bright, light blue. The sensitizer is unpleasant black-green. Once mixed it will turn out bluish green.
Ideally, all mixing and application operations on the screen surface should be carried out in a relatively dark room so that as little light as possible falls on the emulsion.
The mixed emulsion can be stored in a bottle in a cool place for 8 weeks at room temperature or 4 months in the refrigerator.
Lay the newspaper on the work surface to protect it from photo emulsion and paints.
Since the screen will turn over many times during operation, we will install a pushpin in the corners of the frame.
If you don't have a rubber spatula, use a piece of cardboard to spread the emulsion evenly over the mesh.
Let's start from the bottom of the screen to the top. Apply a thick line of emulsion from one end of the frame. Using a spatula, spread it evenly over the entire surface in a thin layer. Let's turn the screen over and put it on the buttons. Apply a layer of emulsion to the inside and spread it with a spatula.
We repeat this process until we achieve a thin, uniform layer of emulsion that will cover the entire screen. This does not require more than two passes. You need to work quickly to minimize the amount of time the emulsion is in direct sunlight. The final result should be a smooth surface onto which ink will subsequently be applied.
After finishing work, install the screen on the buttons in a dark place to dry. You can cover it with a cardboard box or leave it in a closed cabinet.
We leave the emulsion overnight to dry, but if you want to speed up the process, you can point a fan at the screen.
The easiest way to make a template is to print a black and white image on transparent film. The image can be composed in a graphics editor or drawn on white paper, and then scanned for further printing.
The light table consists of several fluorescent lamps mounted under translucent acrylic. It may take several experiments to figure out the exposure time. Depending on the light intensity, the exposure time can be around 4 or 5 minutes.
But in this project we use a simple 150 W lamp with a reflector.
Necessary:
We will hang the lamp with a reflector so that the “sun” is at a height of 30 cm (for a screen measuring 25x35 cm) above the surface of the screen and is located in the center. Let's place a black cloth on the surface where the screen will be placed. Let's check the readiness of the image template so that it lies in the correct position.
Keep in mind that you will end up with a mirror image. This is especially important for text!
Place the transparent template with the image on the screen, and then place a sheet of acrylic on top so that it fits tightly to the screen. Let's make sure that the distance between the lamp and the screen is correct. In the case of a screen measuring 25x35 cm and a 150 W lamp, the process will take 45 minutes.
Once the exposure is complete, remove the acrylic sheet and clear template and then rinse the screen.
The water should be warm. To remove the emulsion, use a shower head. Even unexposed emulsion “loves to stick” to the fabric. We will see clear places where the surface was exposed to light. We'll lightly wipe the screen with our fingertips, but if the image has fine details, we may lose some of the nuances by wiping excess emulsion around the edges of the image. Let's point the screen towards the light, the grid should be completely clean and open in the unexposed areas of the image. If this is not the case, continue the water procedures.
After the screen is washed, let it dry completely.
Below is an exposure chart for photographic emulsion with 150W and 250W incandescent lamps.
20×25 cm 30 cm 45 minutes
25×35 cm 30 cm 45 minutes
30×45 cm 38 cm 1 hour. 14 minutes
40×50 cm 43 cm 1 hour 32 min
45×50 cm 43 cm 1 hour. 32 minutes
Screen Size Exposure Height Time
20×25 cm 30 cm 10 minutes
25×35 cm 30 cm 10 minutes
30×45 cm 38 cm 16 minutes
40×50 cm 43 cm 20 minutes
45×50 cm 43 cm 20 minutes
It's better to work together. This way, one person can hold the screen on the fabric while another person applies the ink.
We use textile ink for printing on fabric.. If you are printing on new t-shirts, make sure they do not fade.
To print on T-shirts, I recommend making a spacer out of cardboard and pushing it inside so that the ink does not completely saturate the fabric. Let's put a book or a piece of cardboard that is slightly smaller in size than the screen on the fabric, so that it can be pressed tightly against the T-shirt.
It will take time to figure out which printing technologies are best for a particular screen, ink and fabric. For these prints, we'll place the fabric on a piece of cardboard and then place the screen on top.
Pour some ink onto the screen, then use a spatula (at a 45 degree angle) to spread it over the open areas.
Other tips and tricks:
The ink used in this project is quite old, so it doesn't flow as well as I'd like. Ideally, you can add a little water.
Printing on paper:
The process is quite similar to fabric. Different types of paper and ink will behave differently, so experiment a little to find out how it works. The rough and porous surface of paper generally accepts ink well. “Light” paper often wrinkles under the influence of ink, while glossy paper does not accept ink well and tends to smudge.
Again, be sure to rinse all paint from the screen when you're done. Ink that dries on the screen will clog the network. Also rinse the utensils and brushes you used. Close the ink container tightly. If you have any photographic emulsion left over, make sure it is stored in a cool, dark place.
If you are not going to print anything else, you can remove the emulsion. Follow the instructions on the bottle. Wear gloves and know that it will take a lot of hot water and time to get a clean screen.
After the ink has completely dried on the fabric, set the iron to the highest temperature. Place a piece of fabric between the sole and the design, then iron the image on each side for 3 to 5 minutes.
Nice crafts and creative inspiration!
As a result of a long search for housing design options, I came across a description of silk-screen printing at home on the Internet. Options with Oracle stencils, decals, the option I used with stickers and other options have not stood the test of time, something (like stencils) is only suitable for fairly thick elements and large inscriptions. I was unable to order silk-screen printing for the production of single copies (or small series, say up to 5 pieces) at an affordable price. As a result, the experience of silk-screen printing at home appeared.
Briefly, the essence of the technology is that a frame with a mesh is made, a photo emulsion is applied to the mesh, a photo form is printed - what is closed masks the photo emulsion from exposure, so that the unexposed photo emulsion can be washed off. It is exposed under a lamp with a UV spectrum, washed - we get a stencil. Next, we press the paint through the stencil with a squeegee (see below) - the paint is pressed through the washed sieve cells and hits the surface on which we are printing.
I strongly recommend surfing the Internet and watching videos, reading what and how, since there are different nuances in this story - until you try, you won’t understand the meaning. Here is a resource with sensible advice and videos http://www.blog.shelkograf.com/, there is such a course on the network: Kosarev I. - Silk-screen printing technology 2007 (home-made lessons on silk-screen printing) can be downloaded in torrent networks, etc. Here is a forum where people more or less professionally engage in silk-screen printing - http://www.agalsea.ru/forum5/
What's good for us is that we only need to print one color, the quality for DIY is also acceptable. You don’t need rotary machines, you don’t need super high-quality stencils to print a raster, etc.
Homemade squeegee cuvette. Made from aluminum corner, bought at the construction market or in a store like Obi or Leroy).
We cut it out and fasten it with bending bolts. The photographic emulsion is quite thick - it should not leak.
Raquel. Squeegee rubber - hardness - 85. The holder is made of two pieces of lining and is clamped with bolts. If you don't mind the money, you can buy a branded aluminum holder.
For printing and exhibiting, I assembled such a table from bars of old hinges and a piece of glass. Exposure is carried out with a 400 W DRL lamp without a bulb and a 500 W halogen lamp. We place the lamps under the table and expose through the glass. I get about 40 minutes. This is where you need to experiment...
It is recommended to make frames from aluminum. Can be ordered from specialized offices. It's actually quite expensive. It is advised to assemble it from wood - a tenon groove. But my hands are crooked - I couldn’t assemble an even frame - I assembled a device for tensioning the mesh from it, and cut the frames out of 15mm plywood.
We fasten the sieve with a construction stapler. Sieve - number 120 (mesh size). It’s an expensive thing, but a meter (it’s better when they sell it by the unit) is enough for a couple of frames.
The frames should be painted so that they do not delaminate from water and chemicals. Well, if you print often, it is better to order an aluminum frame.
From a failed frame I made a device for tensioning the sieve - bolts were inserted into the holes, nuts into the transverse holes. We attach the frame, cover it with a mesh, secure the mesh and tighten it. After tensioning, we attach the sieve to the frame.
Traces from attaching the sieve to the tensioning frame. I fasten the sieve with buttons while tensioning. Then we trim the edges of the mesh.
Now a little about chemistry.
Photo emulsion. I used a two-part one (the one they sold). Consists of an emulsion and a sensitizer. Mix and get a photosensitive emulsion. I have Foteco 1010. But the sensitized emulsion does not last long. You can try a one-component emulsion (ready-made) - such as Foteco 1834.
Paint - I used solvent, series 572 Finnish. Be sure to take a retarder for the paint (for 572 solvent - 503-99033) - during the printing process the paint dries and clogs the sieve. The retarder prevents the paint from drying quickly and makes the printing process easier.
Removers - during the printing process, sometimes the sieve becomes clogged with dried ink - a cleaning agent such as Pregan 235S - solvent spray. After printing, it is better to wash the stencil with a special solvent. But if there is nothing, you can use regular 646 or solvent. It's true that they don't wash well, the paint curls up. It is imperative to have at least a tool like a pregan 235, or something similar, it’s called a screen opener.
After the stencil is no longer needed, it is regenerated and the hardened emulsion is washed off. There is special chemistry. Many people use whitening bleach - place the frame in a whitening solution for a day. As a rule, everything goes well.
In general, if you get the hang of it, you get some pretty good panels. Of course there are flaws - the pros will of course say that it couldn’t be worse, but IMHO it’s quite good for DIY. The main thing is to make a good stencil. Finally, a few photos of the panel print for the Pultec EQ:
Here you can see that the photo form was not of high quality - the toner did not cover the film tightly - and part of the stencil was illuminated. The result was a fuzzy stencil.
A couple more pictures (the device is assembled).
In general, of course, it’s a dirty business - but you can really get your hands on it. And achieve better quality. And the fact of independence and the ability to produce any panel cannot but rejoice.
I hope the experience will be useful to someone.
Screen printing is a universal and inexpensive method of printing using a ready-made silk stencil. If your client wants a universal design or you just want to give free rein to your creative abilities, you can try making your own stencil for silk-screen printing. Although you may need specialized equipment such as a vinyl cutting plotter or silk-screen emulsion to make a stencil, the stencil can also be cut simply by hand. With sufficient practical experience, both beginners and already quite professional craftsmen can easily make stencils from suitable materials.
Draw or transfer the outline of the design onto mylar or vinyl. After choosing a suitable design, transfer the corresponding image onto the selected material to make a template. For this purpose, use a marker with a thin tip so that your design is clearly visible. Secure the film or vinyl with masking tape to more accurately outline the design.
Attach Mylar or vinyl to hard, clear plastic (such as acetate). This is a necessary preparatory step for cutting out the template. Again, use masking tape to secure the design in place. Position the mylar or vinyl so that the plastic extends at least 1 inch beyond the edges of the design.
Cut out the stencil with a sharp knife. Similar to using a vinyl cutting plotter, creating a stencil by hand requires precise cutting. Using a sharp utility knife, remove any areas of Mylar or vinyl that will not interfere with the design. Be very careful when creating complex designs so that you don't accidentally remove the wrong areas of the design.
Attach the stencil to the screen for screen printing. Apply transfer film evenly to the back of the stencil. When you're ready, remove the film backing and apply the stencil to the silk screen as evenly as possible. The stencil must be applied to the back of the silk screen so that the design will not be damaged when it passes through the printing press.
Load the file into the vinyl cutting plotter. When you export your file to your plotter, your stencil template will be ready to print. The plotter will trace the contours of the design with its knife and create a vinyl stencil for you. Depending on the complexity of the design, the entire process can take from a few minutes to an hour.
Trim off any excess vinyl stencil. Use a sharp knife or other special tool to remove excess vinyl. The thickness of the knife used depends on the complexity of the stencil: the more complex the pattern, the thinner the knife required.
Create a vinyl frame for your silk screen. Cut a piece of vinyl that fits the size of your silk screen to serve as the frame for your stencil. Using a sharp knife, cut out a rectangle from the middle large enough to accommodate your stencil. Place the prepared frame on the mesh screen and secure with masking tape.
Use transfer film to secure the stencil. Stick the transfer film as evenly as possible to the back of the stencil. When you are ready to transfer the stencil to the screen for screen printing, remove the backing from the transfer film and secure the stencil in the previously cut rectangular slot. Using confident hand movements, smooth out the stencil so that there are no air bubbles left underneath.
Coat the silk-screen mesh screen with photo emulsion. Photoemulsion is a gel-like substance that is sensitive to light. When applied to fabrics such as silk, it is able to absorb images from photographic paper and thereby create stencils. Apply a thin layer of emulsion to both sides of the screen, leaving a border of about 2.5 cm around.
Place the screen in a dark room or light-proof box. After covering the screen with gel, you need to let it dry in the absence of light. Immediately place it in a dark room or light-proof box where ultraviolet light cannot touch the screen. The drying process will take 3-5 days, depending on the size of the screen for screen printing.
Print your stencil design onto clear film. After the screen has dried, you need to print the design of the future stencil on transparent film for printing. Most printers are compatible with transparencies, but you may need to adjust your printer settings accordingly. Consult your printer's user manual for specific instructions.
Why is optimal exposure time important?
High-quality screen printing directly depends on the correct exposure time when making the stencil. 99% of defects in the finished stencil are caused by underexposure:
Loss of small parts during washing
A large number of pinholes
Premature stencil failure during printing or deinking
Difficult or impossible stencil regeneration
What is the optimal exposure?
In conventional diazo (diazo) and diazophotopolymer (dual-cure) photoemulsions, it is necessary to add a photosensitive component - diazo sensitizer, which absorbs blue and ultraviolet light. During exposure, this substance disintegrates and the stencil is “stitched”. This occurs throughout the entire thickness of the stencil. Remember that the emulsion layer on the grid on the side of the light source will light up faster, while the layer on the other side of the grid will take some more time.
Unlike diazo emulsions, one-component emulsions based on pure photopolymer already contain light-absorbing ingredients, which cause the stencil to “crosslink.” Although such emulsions are exposed faster than diazo-containing emulsions, additional time is still needed to illuminate deeper layers (on the back side of the grid).
Always remember this, since it is the underexposed emulsion on the back of the mesh that reduces the durability of the stencil.
As you know, many people deliberately make underexposed stencils, since this way guarantees high resolution for highly detailed printing - this is common practice. This technique is often used under unfavorable conditions, for example, using low resolution emulsions on white grids. Today, thanks to high-quality emulsions and colored mesh, it is possible to obtain a stencil with a resolution greater than the inks that will be printed through it can provide. So, as long as you use high quality materials in making your stencil, resolution will not be a factor in your exposure time.
What influences optimal exposure?
If you ask 100 stencil makers to list the factors that affect exposure time, the answers will be almost the same. But if you ask them to list these factors in order of importance, you'll probably get 100 different options.
There are basically six factors to consider (listed in order of importance):
Light intensity
Distance from lamp to stencil
Mesh thickness
Grid color
Emulsion layer thickness
Emulsion type
How can I quickly and accurately determine the optimal exposure time?
While there are several ways to determine exposure (including "color change"), a new method has emerged that cuts through the time-consuming and less accurate methods. By measuring the intensity of radiation in a narrow spectral range (actinic light), to which photoemulsions are most sensitive, it is possible to predict what the required shutter speed will be.
The device used in this method is a digital radiometer. Manufacturers of photosensitive materials, based on their tests, provide data on the level of radiation required for correct exposure.
Benefits from secondary exposure of the stencil (post-exposure).
Post-exposure can be a useful technique for increasing stencil durability. The benefits obtained from this method depend on the type of emulsion.
Diazo emulsion.
When the diazo emulsion is underexposed, the developed and dried stencil retains the yellowish tint from the unused diazo sensitizer (this is the basis for the "color change" method of determining exposure). This partially exposed diazo does not wash out of the stencil during development because it is already bound to the polymerized areas. After drying, the stencil can be further exposed, which will discolor the diazo, improve cross-linking, and improve resistance to solvents and water. However, it should be remembered that depending on the initial degree of underexposure, the stencil, although chemically “crosslinked,” may not be durable, and micro-holes may appear, unlike a stencil that is immediately correctly exposed. There is absolutely no point in post-exposing a properly exposed stencil since all the diazo has already been used.
Diazophotopolymer (dual-cure) emulsions.
With underexposure, the situation is the same as with diazo emulsions, that is, post-exposure will allow you to “stitch” the stencil and improve resistance to solvents and water. However, the difference is that even a properly exposed dual-cure emulsion can benefit from post-exposure. The reason is the second (additional) “cross-linking” system, which makes the emulsion “double” and polymerization continues even after all the diazo has been used. This usually only improves solvent resistance and may make the stencil easier to regenerate.
Photopolymer emulsions (one-component)
These photographic emulsions benefit most from post-exposure. Unlike diazo, which can be used 100% if exposed to light for a long enough time, photopolymer molecules can be very “stubborn”. Only some of them react very quickly and are responsible for the short exposure time of photopolymer emulsions. The rest of the molecules remain unaligned and are difficult to cross-link. In this case, increasing the exposure time will degrade resolution and detail, while slightly improving durability. However, the potential of unused photopolymer can be exploited using post-exposure, since during development (washing) when the stencil is wetted, some of the unreacting molecules align and become available for "cross-linking" in post-exposure. Thus, the resistance to solvents and water is improved.
Based on materials from SAATI Americas
