The present invention provides a preparation method for a composite porous structure, comprising the following steps: step (a): preparing a porous substrate having multiple pores, a first surface and a second surface; and step (b): continuously feeding a cooling fluid to contact the first surface and to flow continuously to the second surface through the pores of the porous substrate, and heating a coating material to multiple molten particles by a heat source and spraying the molten particles onto the second surface of the porous substrate, so as to form a coating layer having multiple micropores on the second surface of the porous substrate and obtain the composite porous structure formed. Besides, also provided is a composite porous structure prepared by the preparation method.

A method of making depth filtration media, such as for use in a depth filter, are described. The resulting depth filtration media includes a core tube having two or more different layers. The layers can be fibers, such as polymeric or inorganic fibers, wrapped layers of a filter material, or pleated and folded layers of a filter material.

A polyolefin microporous membrane has excellent strength, permeability and heat resistance, which is obtained by using UHMwPE and employing a sequential stretching system, and a production method of the microporous membrane. In producing a microporous membrane by using a primary material A having a molecular weight (Mw) of less than 1.010.sup.6, a secondary material B having a molecular weight of 1.010.sup.6 or more, and a plasticizer, when the endothermic quantity of a mixture of the primary material and the plasticizer and the endothermic quantity of a mixture of the secondary material and the plasticizer are denoted as Q1 and Q2, respectively, respective resins are designed such that the ratio of endothermic quantity Q2 to endothermic quantity Q1 (endothermic quantity Q2/endothermic quantity Q1) becomes 1 or more over a temperature range of 110 to 118 C.

Features of relatively low pressure microporous (and preferably plant-responsive) irrigation tubes are combined with features of relatively high pressure drip emitter tubes to produce a hybrid irrigation tube. Methods for using and manufacturing the hybrid irrigation tube are also disclosed.

Described is an osmotic distillation process for concentrating a liquid containing sodium chloride, and in particular a treatment process for used reaction water containing sodium chloride from the production of polymers.

This ionic liquid-containing laminate includes a porous layer having affinity with ionic liquids (C), said layer holding an ionic liquid-containing liquid (A) within voids therein, and a porous layer lacking affinity with ionic liquids (B). The porous layer having affinity with ionic liquids (C) may include an inorganic material (e.g., metal oxide particles having an average particle size of 0.001 to 10 m on a number basis). The ionic liquid-containing liquid (A) may include an ionic liquid containing cations selected from ammonium, imidazolium and phosphonium cations, and anions selected from fluorine-containing anions, cyano-containing anions and amino acid-derived anions. The porous layer having affinity with ionic liquids (C) may include 1 to 100 volume parts of the ionic liquid-containing liquid (A) with respect to 100 volume parts of voids therein. The ionic liquid-containing laminate is easily formable, and is able to stably hold (or fix) the ionic liquid while maintaining said liquid in a liquid state.

A method for treating a surface of a microporous membrane includes: (1) contacting at least one surface of the membrane with a treatment composition including: (a) an acrylic polymer prepared from a mixture of vinyl monomers including: (i) a (meth)acrylic acid monomer and (ii) a silane-functional acrylic monomer; and (b) a base, where the acrylic polymer is in contact with the filler present in the matrix; and (2) subjecting the membrane of (1) to conditions sufficient to effect a condensation reaction between the filler and the acrylic polymer. A treated microporous membrane and an aqueous treatment composition are also disclosed.

Disclosed are a polyolefin resin composition usable in manufacturing a single-layered dry porous membrane having excellent meltdown and shutdown properties, and a porous membrane using the polyolefin resin composition. The present invention provides a polyolefin resin composition for a porous membrane, wherein the polyolefin resin composition includes 30 wt % to 70 wt % of a high-density polyethylene having a melt flow index (190 C., 2.16 kg load) of 0.1 g/10 min to 5 g/10 min, a crystallization temperature of 115 C. to 125 C., and a degree of crystallinity of 75% or greater, and 30 wt % to 70 wt % of a high-crystallinity polypropylene having a melt flow index (230 C., 2.16 kg load) of 5 g/10 min to 20 g/10 min.

A semipermeable membrane support containing polyolefin-based fibers, which can withstand repeated washing and backwashing, makes it easy for a semipermeable membrane component to permeate thereinto and difficult for the component to strike therethrough, and is excellent in adhesion to the semipermeable membrane and adhesion between a non-coating surface thereof and a resin frame. The semipermeable membrane support which is used by forming the semipermeable membrane thereon is a wet-laid nonwoven fabric containing core-sheath type conjugate fibers composed of polypropylene as a core component and polyethylene as a sheath component and has a burst strength of 300 to 1,000 kPa, or the Bekk smoothness and 75 mirror surface glossiness of the coating surface on which the semipermeable membrane is to be formed of the semipermeable membrane support being more than the Bekk smoothness and 75 mirror surface glossiness of a non-coating surface on the opposite side.

The present invention relates to a porous sheet product, to a filter element comprising the porous sheet product, to a method for producing the porous sheet product, to a method for producing the filter element, and to the use of the sheet product and of the filter element.