Jujo Paper Co., Ltd.

Nippon Paper Industries Co., Ltd.

Yoshitomi Pharmaceutical Industries, Ltd.

Seiko Chemical Industry Co., Ltd.

Nippon Paper Industries, Ltd.

Yoshitomi-pharmaceutical Ind., Ltd.

Toshimi Satake

Tomoaki Nagai

Fumio Fujimura

Toshiaki Minami

Akio Sekine

Toshiyuki Takano

Miyuki Yokoyama

Hiroshi Fukui

Hideki Hayasaka

Yukiko Uehori

Masato Magami

Motoi Fukuda

Satoshi Oda

Yoshihide Kimura

Tadakazu Fukuchi

Kazuo Maruyama

Mitsutoshi Nakamura

Toshio Kaneko

Kaoru Hamada

Hideki Fujiwara

Noboru Yamato

Manabu Mori

Masuhiko Sato

Masahide Taniguchi

Yukiko Oohira

Jyunichi Komai

Makoto Iwaguro

To accommodate recent progress in printing technologies including conversion to offset printing, color printing, high-speed mass printing and automation of printing, by providing a coating layer containing an inorganic surface preparation agent mainly comprising silica sol and colloidal silica or a coating layer containing an inorganic surface preparation agent, to which an inorganic pigment, surface-sizing agent, inorganic salt and/or organic binder accordingly added in addition to silica sol or colloidal silica, offset paper serviceable for newsprint paper, which has improved qualities such as high whiteness, excellent water absorption resistance and ink acceptability, few adhesion troubles such as surface tack and curling caused by adhesion, and low chemical oxygen demand COD) load in wastewater when recycled, is provided.

Offset printing paper

A novel method for measurement of dynamic water break resistance capable of predicting a degree of paper-cutting at the time of an offset printing and an apparatus for carrying out this method are provided. Both ends of a specimen paper having a size of short-side of from 3 to 15 mm and a long-side of from 120 to 320 mm are kept by a fixed chuck and a movable chuck positioned with a fixed spun length on a measurement table; from 1 to 30 .mu.l of water is attached from a device unit for automatically attaching water onto a central portion of the specimen paper; after the attachment of water, a load is rapidly applied from the both ends of the specimen paper to measure a tensile strength of the specimen paper at the time of attachment of water; and a tensile strength of the specimen paper at the time of drying, i.e., in a state before the attachment of water, is also measured; and a dynamic water break resistance is displayed and evaluated from a percentage of the tensile strength of the specimen paper at the time of attachment of water to the tensile strength of the specimen paper at the time of drying.

Method and apparatus for measurement of dynamic water break resistance

A printing paper, especially a newsprint base paper, comprising: a base paper; and a coating layer for improving surface strength of the coated paper and releasing-property when two sheets of the coated paper are stacked, which coating layer is formed on the base paper by using a coating-transcription system such as a gate roll coating system, which coating layer comprises at least either a homopolymer polyacrylamide or a nonionic-copolymer polyacrylamide in a coating weight of from 0.01 g/m.sup.2 to 0.2 g/m.sup.2, wherein the homopolymer polytcrylamide and the nonionic-copolymer polyacrylamide have a weight average molecular weight ranging from 20,000 to 250,000, thereby improving not only surface strength but also releasing-property in a printing paper, especially in a newsprint paper having a basis weight less than 46 gm.sup.2.

Printing paper coated with nonionic acrylamide and method of producing

A printing paper, especially a newsprint base paper, comprising a base paper, suitably lightweight acid base paper, and a coating layer for improving surface strength of the coated paper and releasing-property when two sheets of the coated paper are stacked, which coating layer is formed on the base paper by using a coating-transcription system such as a gate-roll coating system, which coating layer comprises low-molecular anionic polyacrylamide in a coating weight of from 0.01 g/m.sup.2 to 0.2 g/m.sup.2, wherein the anionic polyacrylamide have a weight average molecular weight ranging from 10,000 to 150,000, thereby improving not only surface strength but also releasing-property in a printing paper, especially in a newsprint paper having a basis weight less than 46 g/m.sup.2.

Printing paper coated with low-molecular anionic acrylamide and method

Printing paper such as newspaper printing paper, the water absorbency of which is controlled by coating material for controlling water absorbency on the surface of base paper, wherein the coating material contains component A which is at least one water-soluble polyacrylamide selected from nonionic polyacrylamides, cationic polyacrylamides, and water-soluble polyacrylamides, and component B which is water-soluble anionic polymers of monomers having hydrophobic substitute(s) and monomers having at least carboxyl group(s) or sulfone group(s).

Printing paper and newsprint paper with improved water absorptivity and

A near-infrared absorbent is obtained by heating a dimerized thiourea derivative of Formula �1! or �2! and a copper compound: ##STR1## The near-infrared absorbent is used to obtain a near-infrared absorbent resin material having a wide absorption in the near-infrared region, and the absorbent does not substantially decompose at a molding temperature of the resin. Typical examples of the dimerized thiourea derivative are 4,4'-di(benzylthiocarbamoyl)-aminodiphenylmethane, 4,4'-di(benzylthiocarbamoyl)-aminodiphenylhexafluoropropane, and 1,4'-di(dibenzoylthiocarbamoylamino)-2,5-dimethylbenzene, and typical examples of the copper compound are copper stearate and copper .beta.-acryloyloxypropylhydrogenphthalate.

Dimerized thiourea derivatives near-infared absorbents comprising the

An optical recording medium including a substrate having thereon a recording layer containing a dye precursor, a color developer reactable with the dye precursor to develop a color, and a light absorbent for converting light to heat, characterized in that the color developer is at least one compound of Formula (1):

Optical recording medium

In a thermal recording material having a thermal recording layer containing a colorless or pale colored dye precursor and a color developer reactable with the dye precursor upon heating to develop a color of the dye precursor, the color developer is a bisurea compound, for example, Compound A-2. The thermal recording material is superior in stability of background color.

Thermal recording material

In an optical recording sheet having a thermal recording layer containing a colorless or pale colored dye precursor and a color developer reactable with the dye precursor upon heating to develop a color, a dimerized or trimerized urea compound is used as the color developer to obtain an optical recording sheet which is superior in ground color stability and an optical recording sheet having a reversible recordability.

Optical recording sheet

It is provided with a thermal recording material having a support coated with a coating solution as a color developing layer. The color developing layer has a colorless dye precursor which is normally colorless or light-colored, and a developer which reacts with the dye precursor to cause color development thereof upon heating. The developer is a bisthiourea compound represented by, for example, a formula (A-2): ##STR1## and the thermal color developing layer contains no sensitizer. In the thermal recording materials of the present invention, substantially no color is developed at a temperature of 120.degree. C. while color development can be caused in response to heating with a thermal head or a laser beam. The developed color on the material can be erased upon contacting with alcoholic solvents, depending on the thiourea compound contained in the color developing layer. After erasure of the image, the material can be used again for recording with a thermal head or a laser beam.

A benzoin compound is synthesized from phenylglyoxal and a substituted benzene derivative, and the resulting benzoin compound is converted to a bis-dithiobenzilnickel complex using phosphorus pentasulfide/nickel chloride. The bis-dithiobenzilnickel complex is useful as a near-infrared absorbing material to be coated on paper, and the benzoin compound is useful as an intermediate of the complex. The obtained bis-dithiobenzilnickel complex can be applied to an optical recording material, a near-infrared absorbing resin, a near-infrared absorbing hard coating agent and a near-infrared absorbing glass composite.

Optical recording material comprising a bis-dithiobenzilnickel complex

A dispersion of a carbonate type blocked color developer having a hydroxyl group having a color developing function which is blocked by an O-substituted oxycarbonyl group (--(C.dbd.O)OR.sub.1), and a metal salt of an organic acid or inorganic acid or a leuco dye are mixed to obtain an opaque undeveloped coating color, and the coating color is coated on paper or the like to obtain a recording sheet. Also, the coating color is further mixed with a light absorbent to obtain an opaque undeveloped coating color, which is coated on paper or the like to obtain an optical recording sheet.

Recording sheet

In a thermal recording sheet having a thermal recording layer containing a colorless or pale colored dye precursor and a color developer reactable with the dye precursor upon heating to develop a color, a dimerized or trimerized urea compound is used as the color developer to obtain a thermal recording sheet which is superior in ground color stability and a thermal recording sheet having a reversible recordability.

Thermal recording sheet

A transparent recording medium is disclosed which can directly record a fine, precise image. With the recording medium, a compact, fine image occupying a small storage space can be easily enlarged and confirmed by an enlarged projection. It is prepared by applying a coating liquid for recording comprising a developer in which a hydroxyl group with a developing function is blocked by an N-substituted carbamoyl group or an O-substituted oxycarbonyl group, an iron salt of an organic acid or a leuco dye, a near-infrared absorbing agent, and a binder, uniformly dissolved in an organic solvent such as MEK, to a transparent plastic substrate, and drying to obtain a transparent recording layer with a thickness of 3 .mu.m to 8 .mu.m. A visible, precise, fine direct image can then be recorded using a semiconductor laser beam.

Transparent recording medium

A hard-coating, heat-absorbing composition which is capable of absorbing near-infrared rays from sunlight and a heat-shielding substance is disclosed. The composition comprises a silicone varnish for hard-coating comprising polysiloxane and, dissolved therein, diphenylthiourea and copper monobutyl-o-phthalate. It can be applied to plastic substrate and heated to cure the silicone varnish, whereupon curing of polysiloxane and production of a heat-absorbing compound are simultaneously effected. The composition ensures to provide various substrates with a heat-shielding characteristic.

Growing community of inventors

Tokyo, Japan

Toshimi Satake