1, material inspection: panels, substrate, silver paste, carbon ink, spacers, adhesives, glue, reinforcement plate, insulation printing should comply with the regulations of the drawings.
Comparison, shape: shape, conductor lines, insulation treatment, combination of lining board, should comply with the regulations of drawings or provide samples.
Check the size: 3, drawing did not note tolerance allowed range to conform to the standard, the rest of the conform to the requirement of drawings.
4, check the appearance: panel cannot have obvious flaws, such as characters of stroke;Stain, pervious to light point;Deinking, spots, scratches;Transparent window glue, glue, etc.Unbiased phenomena, such as printing, registering, top and bottom line and specialized line combined with key piece, panel and buttons, bubbling and substrate panel buttons.Bend size stamping burrs and crowded, should not be greater than 0.2 mm, and no conductor position should be facing a side.
5, check the color: using visual method, compared with the sample or color card to see if have off color, color is particularly strict with color difference meter.
6, the printing ink adhesion check: ink by scotch tape attached with a hand pressure to ensure that no bubble quickly stripped after 10 seconds, can not have ink drop phenomenon.Insulation dry ink, the ink surface abutting again after 24 hours, the weight of each other to ensure that the insulation surface does not stick to each other.No bubble with a pressure sensitive adhesive tape attached with a hand pressure after 1 minute, rapid stripping, no ink peeling.
7, peel strength test: adhesive peel strength, shall be not less than 8 n / 25 mm.
8, bubbling test: equal height, strength equilibrium.Planar: 57 ~ 284 g, touch feeling: 170 ~ 397 g.
9, folding strength test: after drying process of silver paste, carbon ink lines, should first determine the loop resistance, and then to 180 degrees of fold on the line, and with finger pressure 2 kg / 2 seconds, and then to restore the plane, so implement 5 back to back and forth, then measure the resistance.Due to fold after 5 back to increase the resistance of not more than 300% in the original resistance.
10, hardness testing, with H class drawing written, pressuring line 1 kg thrust, 45 degrees lines must not have conductive ink peeling or produce pervious to light.
11, life test: no shrapnel each key contact conduction number, should be in 1 million.Shrapnel and touch type conduction number, should be in 500000.
12, detection circuit resistance: resistance value should be not more than 100 Ω, special requirements for the circuit is greater than the total length of 150 cm and loop resistance other provisions on the drawings.Don't allow any break, short circuit phenomenon.
13, insulation resistance testing: in normal temperature often wet environment, the insulation of the conductor line resistance is greater than 500 m Ω vdc1 (500 minutes).After the high temperature and humidity test, salt spray test should be not less than 20 m Ω.
14, high temperature test: membrane switch to withstand 55 + 2 ℃, 72 hours after high temperature, check the appearance quality should comply with the regulations of the drawings.Under the condition of normal atmospheric back 2 hours, measuring insulation resistance should comply with the rules.
15 and low temperature test: membrane switch - 10 + 3 ℃, over 16 hours after low temperature effect, restore 2 hours under normal atmospheric conditions, wipe the surface water, resistance should comply with the rules.
16, salt spray test: membrane switch endure the salt solution of sodium chloride 5%, 35 + 2 ℃, the temperature test space (connector) after 72 hours salt spray test, restore 2 hours under normal atmospheric conditions, insulation resistance should comply with the rules.
17, constant humid heat test: membrane switch to withstand 40 + 2 ℃, relative humidity of 93 (+ 2% - 3%), after 96 hours of constant humid heat test, restore 2 hours under normal atmospheric conditions, measure the insulation resistance, loop resistance, strength of button should comply with the rules.