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| To insure proper resolution and durability of the stencils, polyester mesh requires degreasing, and sometimes abrading. New NBC polyester monofilament mesh has a special surface treatment, which reduces production time and eliminates the need for chemicals, thus reducing cost and environmental impact. |
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| Comparison of washing distance time |
Process
(Time in min.) |
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Conventional mesh |
| Direct emulsion |
Stencil film |
Direct emulsion |
Stencil film |
Degreasing/
Abrading |
0.0 |
0.0 |
5.0 |
5.0 |
| Rinsing |
0.5 |
0.5 |
0.5 |
0.5 |
| Drying |
30.0 |
0.0 |
30.0 |
0.0 |
| Coating |
5.0 |
1.0 |
5.0 |
1.0 |
| Drying |
min. 120.0 |
min. 120.0 |
min. 120.0 |
min. 120.0 |
| Total Time |
155.5 |
121.5 |
160.5 |
126.5 |
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| Note: all NBC meshes are produced in clean room conditions, however, NBC recommends rinsing with water before coating direct emulsions or stencil films. Excessive handling may leave oils and dirt that will require degreasing. |
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The improved surface tension properties of new NBC polyester monofilament mesh is especially suitable for printing small halftone dots and fine lines particularly for stencil film applied with water. Small details are held tightly making stencils last much longer.
In comparison tests between new NBC mesh and conventional mesh, NBC mesh 300% more 0.25mm dots and 400% more 0.5mm dots than conventional mesh. |
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| Test conditions |
| Stencil film: Thickness 15µm, Halftone dot size 0.25mm x 0.25mm and 0.5mm x 0.5mm, image size 2.5cm x 2.5cm, both exposed and developed (348mj/sq.cm) with the same exposure amount and washout procedures and then immediately peeled off with the scotch tape #810 at 90 degrees angle. The number of dots remaining on the mesh are counted. |
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Improved tensile strength and low elongation
The increased mesh strength of new NBC polyester monofilament mesh allows it to be easily stretched to a higher tension level. This makes it possible to reduce off-contact distance for better dimensional stability and printing accuracy with less squeegee pressure. The diagram (below left) shows the tensile strength comparison between L-SCREEN, UX-SCREEN, and EX-SCREEN in the same specification. |
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| Comparison of thread strength |
Construction model of thread |
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The diagram shows the comparison of tension loss after stretching.
Most tension loss in high modulus polyester monofilament meshes occurs within 24 hours of stretching and then continues to drop for three days.
The advanced physical property of NBC high modulus polyester mesh reduces the loss of tension after stretching and maintains tension much longer at press, prolonging the stencil whilst maintaining the highest dimensional accuracy. |
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| [ The stretching condition ]Frame size : 950_950mmStretching angle : straight(90 degrees) |
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L-SCREEN,UX-SCREEN, and EX-SCREEN are compared using a printing endurance test.
The results show the improved dimensional stability and printing accuracy even after 10,000 prints. This translates into longer stencil-life reducing production costs. |
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| Dimensional change after 5,000 prints |
Dimensional change after 10,000 prints |
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| Initial tension before printing |
22 N/cm |
21 N/cm |
Squeegee
pressure |
Zero positioning(kPa) |
80 |
104 |
| Plus positioning(kPa) |
30 |
20 |
| TOTAL(kPa) |
110 |
124 |
| Off-Contact(mm) |
4.7 |
4.7 to 5.3* |
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| * |
Note: Off-Contact distance of EX Screen has to be increased from 4.7mm to 5.3mm
after 5,000 prints. |
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| Dimensional change after 5,000 prints |
Dimensional change after 10,000 prints |
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| Initial tension before printing |
26 N/cm |
26 N/cm |
Squeegee
pressure |
Zero positioning(kPa) |
90 |
90 |
| Plus positioning(kPa) |
30 |
30 |
| TOTAL(kPa) |
120 |
120 |
| Off-Contact(mm) |
3.5 |
3.5 |
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The improved dyne value (surface tension) of new NBC polyester monofilament mesh improves ink transition beyond that of conventional polyester mesh up to the level of nylon mesh. Ink has much less adhesion to the mesh thus improving resolution and press speeds. The magnified pictures below show the comparison of EX130-30/330PW(30µm thread)and conventional polyester 130-30/330PW in ink transition after 100 prints.
There is a reduction in ink remaining on the EX130-30/330PW and the resolution is much sharper than that of conventional polyester mesh. |
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Conventional mesh
130-30/330PW |
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| The special surface treatment of new NBC polyester monofilament mesh gives an anti-static property that prevents dust attachment during the stretching and coating process. The chart below shows the anti-static effect. Anti-Static properties remain even after stencil reclamation. |
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| Friction charge |
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Conventional mesh |
| 120-35/305PW |
150-30/380PW |
120-35/305PW |
150-30/380PW |
| before coating |
1.0kV |
1.0kV |
22.0kV |
22.0kV |
| after reclaiming |
6.4kV |
5.9kV |
13.0kV |
12.0kV |
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| note: Actual static charge will vary due to temperature and humidity. |
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| NBC polyester monofilament mesh undergoes rigorous quality control measures and careful inspection for elasticity, breaking point, mesh count, and mesh thickness which are carefully documented by ISO9001. |
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| Quality standard |
| Mesh count |
Within +/- 3% of catalogue value |
| Mesh thickness |
Within tolerance guaranteed on the specification chart |
| Physical strength |
Breaking point and elongation balance of warp + weft |
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