Innovation of Pencil Lead Drawn Paper Sensors (PLDPS) Using Electrical Resistance (ER) Measurement: I. Optimal Conditions of Interfacial, Mechanical, and Sensing Properties

Abstract

A study was performed to utilize Pencil Lead Drawn Paper Sensor (PLDPS) as a strain and damage sensor by drawing multiply Pencil Sensors on two paper types. To evaluate the optimal paper as a PLDPS substrate of two type papers, i.e., plain and Han papers were used. The stability and uniformity of the mechanical properties, were compared for the paper types. Variability of electrical resistivity (ER) was also determined using four different types of pencil lead to make the PLDPS. In the evaluation of the properties of the PLDPS, for the different pencil lead types, the pencil lead weight was determined by drawing multiple lines and the ER of neat pencil leads and PLDPS compared. Interfacial properties of the PLDPS with different pencil lead types were measured by a spreading test, which provides information on wetting and permeability properties, using double distilled water. The sensitivity and uniformity of the pencil lead paper sensors made of four different pencil leads were compared in tensile loading. Plain paper was more suitable than Han Paper for use as the substrate of PLDPS. In addition, compared to other pencil leads, 6B, which exhibited low sensitivity but high uniformity, was determined to be the most suitable pencil lead.