Which Linqstat product is right for pressure sensors?

A ques­tion came in to us recent­ly about the right elec­tri­cal­ly con­duc­tive plas­tic for pres­sure sen­sors, which we felt was worth answer­ing pub­licly.

The min­i­mum thick­ness suit­able for pres­sure sen­sors is 4mil, but the 6-mil and 8-mil thick­ness­es are more com­mon for pres­sure sen­sors.

Question for Pressure Sensors

The ques­tion that was asked was from a design­er that was design­ing a fair­ly large pres­sure mat with a sen­sor matrix. He was try­ing to fig­ure out the min/max/typical sheet resis­tance for our MVCF and VCF (Mid-Lev­el Con­duc­tive Film vs Low-Lev­el Con­duc­tive Film) prod­ucts. The web­site and the datasheets have con­flict­ing infor­ma­tion. Also, he would also like to know what the vari­abil­i­ty of sheet resis­tance in a sin­gle roll is. Would the vari­abil­i­ty be low­er when using thick­er films?

Answer for Pressure Sensors

Although, we are a lit­tle embar­rassed to admit it, he was right. Over the past 6 months, we have been updat­ing and rec-clas­si­fy­ing our range of vol­ume-con­duc­tive sheet­ing. The rea­son for this is because our cus­tomers have asked for more spe­cif­ic con­duc­tiv­i­ty ranges with tighter tol­er­ances. You can read the post here that talks about tighter spec­i­fi­ca­tions on LINQSTAT vol­ume-con­duc­tive plas­tic for more details.

As a result of this, we have just updat­ed our LINQSTAT Con­duc­tive Plas­tic Sheet­ing Overview page, which has the most cur­rent infor­ma­tion. All the infor­ma­tion on the web­site and in the tech­ni­cal datasheets has been updat­ed to reflect this infor­ma­tion.

As far as the vari­abil­i­ty goes, it is about 10% roll-to-roll due to the dis­tri­b­u­tion of con­duc­tive filler, but is inde­pen­dent of the thick­ness. (the vol­ume resis­tiv­i­ty how­ev­er is of course thick­ness depen­dent). Where the thick­ness plays a role and is par­tic­u­lar­ly impor­tant for pres­sure sen­sor appli­ca­tions. The thin­ner sheets are less sen­si­tive to pres­sure changes than the thick­er ones (because essen­tial­ly by reduc­ing the thick­ness, you increase the con­duc­tiv­i­ty). The min­i­mum thick­ness suit­able for pres­sure sen­sors is 4mil, but the 6-mil and 8-mil thick­ness­es are more com­mon for pres­sure sen­sors.

I am not sure whether you need the 50,000 ohms per square or 10,000 ohms per square prod­uct for your appli­ca­tion, but typ­i­cal­ly the larg­er the pres­sure sen­sor, the less con­duc­tive the film needs to be. You could still use the more-con­duc­tive mate­r­i­al, but then you are pay­ing for con­duc­tiv­i­ty that you don’t nec­es­sar­i­ly require.

CAPLINQ is a spe­cial­ty plas­tics sup­pli­er offer­ing a range of LINQSTAT brand­ed con­duc­tive mate­ri­als includ­ing our broad range of elec­tri­cal­ly con­duc­tive plas­tics and anti­sta­t­ic tapes and films. If you have any ques­tions, please don’t hes­i­tate to con­tact us if you have fur­ther ques­tions on using con­duc­tive plas­tic for pres­sure sen­sors.

About Chris Perabo

Chris is an energetic and enthusiastic engineer and entrepreneur. He is always interested in taking highly technical subjects and distilling these to their essence so that even the layman can understand. He loves to get into the technical details of an issue and then understand how it can be useful for specific customers and applications. Chris is currently the Director of Business Development at CAPLINQ.

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