Sanyo Chemical Industries, Ltd.

Tsuyoshi Yuki

Keiji Tanaka

Satoshi Tamabuchi

Masashi Date

Kenjiro Tsubota

Kenji Tanaka

Shingo Mukaida

Hideo Nakanishi

Minoru Nishida

Yoshiyuki Iwasaki

Satoshi Utsui

Yoshihisa Ota

Daisuke Tagawa

Hitoshi Takai

Friction regulator for lubricating oil and lubricating oil composition

A method for producing an &#x3b1;,&#x3b2;-unsaturated carboxylic acid ester is provided in which an alcohol (A) is caused to react with an &#x3b1;,&#x3b2;-unsaturated carboxylic acid or a lower alkyl ester (B) of the &#x3b1;,&#x3b2;-unsaturated carboxylic acid in the presence of a sulfonic acid group-carrying inorganic porous material (&#x3b1;), and an &#x3b1;,&#x3b2;-unsaturated carboxylic acid ester obtained by the above-described method is provided that contains not more than 50 ppm of sulfur atoms based on a weight of the &#x3b1;,&#x3b2;-unsaturated carboxylic acid ester, not more than 2 mol % of by-product etherification products and not more than 1 mol % of by-product addition products based on the mole number of the &#x3b1;,&#x3b2;-unsaturated carboxylic acid ester. Such methods are a method for producing an &#x3b1;,&#x3b2;-unsaturated carboxylic acid ester that does not involve generation of a large amount of waste products and a method for producing a high-purity &#x3b1;,&#x3b2;-unsaturated carboxylic acid ester that causes only a smaller amount of by-products to be generated, and a high-purity &#x3b1;,&#x3b2;-unsaturated carboxylic acid ester is provided that contains only a smaller amount of catalyst residues and exhibits less metal corrosion behavior.

Method for producing &#x3b1;,&#x3b2;-unsaturated carboxylic acid ester, &#x3b1;,&#x3b2;-unsaturated carboxylic acid ester, and lubricating oil additive

Viscosity index improver and lube oil containing the same

An absorbent composition is produced by drying a mixture obtained by mixing a micro-filler (B) with a hydrogel having a water absorptive resin (A) and water. The hydrogel is produced by performing polymerization to produce the resin (A) and not drying the resin (A) after the polymerization. The absorbent composition has a specific surface area at least 10% lager than that of a reference composition produced by drying the hydrogel without the micro-filler (B).

Absorbent compositions, methods for producing thereof and absorbent products

A water absorbing agent comprising water absorbent resin particles having a particle size of 1000 .mu.m or less, with a two-peak mode particle size distribution, which has an inflection point in the range of 750 to 250 .mu.m particle size prepared by plotting the mass cumulative content percentage from the larger side of the particle size of the particle size distribution on a logarithmic normal probability paper; and an absorbent material utilizing the water absorbing agent. Since the water absorbing agent of the present invention applied in an absorbent material can realize excellent absorption rate of a liquid and planar diffusion, an absorbent material with an excellent surface dryness can be obtained even for a long time use or when the ratio of the water absorbent resin is high due to a thin shape of the product, without the risk of leakage. Accordingly, the water absorbing agent of the present invention can be preferably used in an absorbent material such as a disposable diaper.

Water absorbing agent absorbent material

A method for producing a water absorbent resin by polymerizing a water-soluble monomer having a polymerizable unsaturated group (A) and a crosslinking agent (B) as the essential components by radical polymerization in the presence of water or, polymerizing a water-soluble monomer having an unsaturated group (A) and a crosslinking agent (B) by radical-graft copolymerization with a water-soluble polymer (C) as the backbone polymer in the presence of water, wherein a water-based solid material capable of being endothermally fused or dissolved into water (D) is added when initiating the polymerization, with at least a part of the water-based solid material (D) in a solid state. By the method of the present invention, a water absorbent resin having a high molecular weight and a high absorption capacity with little water-soluble component can be obtained with ease.

Method for preparing water absorbent resin

A method for producing a water absorbent resin comprising the step of radically polymerizing a water-soluble radically polymerizable monomer having an acid group or a group of the salt thereof and optionally a polysaccharide in the presence of water using a crosslinking agent (C), wherein 0.0001 to 1 weight % of a thiol compound (D) having a radically polymerizable double bond, based on the above mentioned water-soluble radically polymerizable monomer (A), is used as the copolymerizing component to provide a water absorbent resin having a high absorbency and a good gel stability after absorbing body fluid, and a water absorbent comprising the water absorbent resin produced thereby.

Method for producing water absorbent resin and water absorbent

A method for preparing water-absorbent resins (D) by radically polymerizing a water soluble monomer (A), or a water-soluble monomer (A) and a polysaccharide (B) in the presence of a crosslinking agent (C) and water, wherein the polymerization is conducted under the existence of a thiol compound (E). Water-absorbent resins obtained in the method of the present invention provide high absorption while providing safety with very little amount of a water-soluble component.

Water-absorbing resin compositions obtained by adding a water-soluble thiol compound in the process of drying or pulverizing a hydrogel of a water-absorbing resin which is obtained by polymerizing a water-soluble monomer having a polymerizable unsaturated group optionally with a polysaccharide, in the presence of a crosslinking agent and water. Composition of the present invention are highly efficient in water absorption and safe for having extremely low amounts of residual monomer and water-soluble component.

Growing community of inventors

Kyoto, Japan

Tsuyoshi Yuki