A microporous material having improved laser marking capability, the microporous material comprising: (a) a polyolefin matrix material; (b) finely divided, substantially water-insoluble filler distributed throughout the matrix material, the filler comprising at least 50 percent by weight of the finely-divided substantially water-insoluble filler particles of finely-divided substantially water-insoluble siliceous filler particles and a positive amount of titanium dioxide; (c) a network of interconnecting pores communicating throughout the microporous material, the pores constituting 10 to 80 percent by volume of the microporous material, determined according to the equation: Porosity = 100 1 − d 1 / d 2, wherein d 1 is the density of the sample, as determined from the sample weight and the sample volume, as ascertained from measurements of the sample dimensions, and d 2 is the density of the solid portion of the sample, which is determined from the sample weight and the volume of the solid portion of the sample; and (d) optionally, a contrasting enhancing amount of a contrast enhancing material selected from antimony oxide and tungsten oxide, pearl luster pigments; kaoline, chalks, aluminas, phyllosilicates, carbon, carbon black, nano-particle carbon, nano-fiber carbon, metallic pigments, aluminum, copper, potassium iodide, copper iodide, zinc sulfide, barium sulfide, benzotriazoles, alkyl sulfonates, thioesters, tin antimony oxide, and tin antimony gray Cassiterite, wherein the sum of the weight percent of the titanium dioxide comprising the microporous material and the weight percent of the optional contrast enhancing material comprising the microporous material is at least 3 weight percent based on total weight of the microporous material. (a) a polyolefin matrix material; (b) finely divided, substantially water-insoluble filler distributed throughout the matrix material, the filler comprising at least 50 percent by weight of the finely-divided substantially water-insoluble filler particles of finely-divided substantially water-insoluble siliceous filler particles and a positive amount of titanium dioxide; (c) a network of interconnecting pores communicating throughout the microporous material, the pores constituting 10 to 80 percent by volume of the microporous material, determined according to the equation: Porosity = 100 1 − d 1 / d 2, wherein d 1 is the density of the sample, as determined from the sample weight and the sample volume, as ascertained from measurements of the sample dimensions, and d 2 is the density of the solid portion of the sample, which is determined from the sample weight and the volume of the solid portion of the sample; and (d) optionally, a contrasting enhancing amount of a contrast enhancing material selected from antimony oxide and tungsten oxide, pearl luster pigments; kaoline, chalks, aluminas, phyllosilicates, carbon, carbon black, nano-particle carbon, nano-fiber carbon, metallic pigments, aluminum, copper, potassium iodide, copper iodide, zinc sulfide, barium sulfide, benzotriazoles, alkyl sulfonates, thioesters, tin antimony oxide, and tin antimony gray Cassiterite, wherein the sum of the weight percent of the titanium dioxide comprising the microporous material and the weight percent of the optional contrast enhancing material comprising the microporous material is at least 3 weight percent based on total weight of the microporous material.