Stretch net
We are a big printing company in Shenzhen China . We offer all book publications, color advertising pictures, hardcover album, packaging box, calendars, all kinds of PVC, product brochures, notes, Children's book, stickers, all kinds of special paper color printing products, game cardand so on.
For more information please visit
http://www.joyful-printing.com. ENG only
http://www.joyful-printing.net
http://www.joyful-printing.org
email: 860681365@qq.com
First, the classification of the stretch nets, the following describes several commonly used:
1, manual stretch net:
It is a method of fixing a screen to a wooden frame by means of a wire mesh jig and a nail and a glue.
Generally, the tension is relatively low, the tension is not uniform, the quality is not easy to guarantee, and the cost is low.
The process flow is as follows:
Making a frame Selecting a net 绷 Stretching Nail nails 修 Trimming the excess screen
2, mechanical stretch net:
Use mechanical force to tighten the screen. When stretching the net, first stretch the radial direction, then stretch the weft direction, and finally alternate the diameter and the weft direction to reach the required tension, so it is evener than the manual stretch net.
The process flow is as follows:
Select the frame Clean the frame Dry Pre-coated adhesive Dry Select mesh
Coating adhesive Drying Cutting the screen and trimming Applying protective tape Drying Making
Mechanical stretch nets are more complicated than manual stretch nets
3, air pressure stretch net:
It is a method of tensioning the screen by pneumatically driving the cylinder of the chuck, and sticking the screen to the frame with the adhesive mesh. The flow is the same as the mechanical stretching method, except that the tension is applied in different ways.
4, the angle of the stretch net is divided into positive stretch net and oblique stretch net:
____ 正 stretching net: It means that the weft wire of the wire mesh is 90 degrees to the edge of the mesh frame. Its advantages are: saving material and easy to stretch the net.
____ oblique stretch net: It means that the weft wire of the wire mesh is at an angle to the edge of the frame. The advantage is that the teeth can be eliminated or reduced. But more expensive materials.
Second, the determination of the net tension:
Screen tension is an important factor affecting the quality of screen printing. The screen tension is tested by a tensiometer
The commonly used tensiometers are the millimeter tensiometer and the Newtonian tensiometer.
When testing, put the tension meter on the tight wire mesh, and let the wire mesh sink by the weight of the tension meter itself.
The degree of sinking is shown on the table. This reading is the tension of the screen. The unit is m m mm or N/CM (Newton/cm). The method is as follows:
Small screen version of the middle point of the medium-sized screen version of the five points of the large screen version of the nine points
Things to be aware of when measuring tension:
____ In order to avoid measurement errors, the instrument should be checked regularly and adjusted if necessary.
____ The minimum distance from the frame when measuring is 10 cm
____ For multi-color (color) printing, all screens should have the same tension
____ The contact shaft of the tension meter contact screen must be placed in the direction of the parallel mesh
____ The tension in both directions of warp and weft should be equal, and the maximum error is more than 1N/CM, if they are not equal
Will result in inaccurate overprinting, uneven thickness of the layer.
Third, the requirements of the stretch net:
1. The tension of the screen on all parts of the screen must be uniform.
2. During the stretching process, the maximum tension shall not exceed the ultimate tension of the screen.
3. The frame must have sufficient strength, and the tension of the screen is stable during the use period.