1. Wire breaking and short circuit: no conductor breaking or short circuit is allowed.






2. Foreign matters: there shall be no foreign matters attached to the line.






3. Conductor thickness: generally, the conductor thickness shall be controlled within 7-12 μ m. And shall be uniform and smooth.






4. Position deviation of upper and lower lines: the center positions of switch contacts of upper and lower lines are offset from each other, and the allowable tolerance is Ф 0.5mm.。






5. Material: substrate, silver paste, carbon ink, spacer, adhesive, adhesive, reinforcing plate and insulation printing shall comply with the provisions of the drawing.






6. Shape: the shape, conductor line, insulation treatment, lining plate combination, etc. shall comply with the provisions of the drawing or provide physical samples.






7. Conductor defects and pinholes: according to the following graphic standards, one is allowed within each 50mm.






8. Carbon ink: the carbon ink covered on the silver paste line shall ensure that the silver paste is completely covered, with a thickness of 8-10 μ m. There shall be no obvious silver paste projection.






9. Stamping burr and die extrusion bending size: the stamping burr and extrusion bending size shall not be greater than 0.2mm, and the position shall face the side without conductor.






10. Contact points of all membrane switches: no insulating ink shall be attached, and the insulating ink surface shall be flat to avoid any bubble, pinhole and other defects affecting the insulation effect.






11. Combined state: the surface shall be free of residual material chips, foreign matters, stains, concave convex, grease attached to the surface and inside, fingerprints on the line and burrs on the punched shape.






12. Scars: all lines and contacts shall be free of cutting marks penetrating the surface (i.e. the cutting marks are cut from the base material on the line). Minor scratches shall also be based on the principle of not affecting its impedance. Carbon ink surface is easy to have scratches, and the scratches shall be based on the principle of not affecting the continuity of the line.






13. Adhesion strength: after the insulating ink is dry, stick the ink surfaces against each other, and then after heavy pressing for 24 hours, ensure that the insulation is not sticky to each other. Apply pressure-sensitive adhesive tape and press it without bubbles for 1 minute. Peel it quickly and there shall be no ink falling off.






14. Jumper: all jumper parts shall meet the requirements of line conductor, and all jumper products shall pass 100% open and short circuit test and insulation resistance test. Ensure that there is no open circuit, short circuit and insulation resistance should be greater than 500m Ω (500vdc1 minutes).