Abstract: The light calcium carbonate in the form of microparticle aggregate of the present invention has a BET specific surface area not smaller than 10 m2/g and not larger than 25 m2/g, a pore volume of 0.05 cm3/g or larger for pores having a pore diameter of 0 to 1000 ? as determined by the nitrogen adsorption method, and a pore volume ratio of 25% or more for pores having a pore diameter of 250 ? or smaller based on the total pore volume as determined by the nitrogen adsorption method, and shows an oil absorption of 100 cc/100 g or more as determined by using liquid paraffin. By using this light calcium carbonate as a filler of printing paper, superior ink absorbing property and opacity (especially opacity after printing) can be imparted to the printing paper.

Abstract: Carbon dioxide containing gas is blown into a calcium hydroxide slurry having a calcium hydroxide concentration of 100 to 400 g/L obtained by wet slaking calcined lime with 4 N hydrochloric acid activity (value at 3 minutes) of 150 to 400 mL to allow them to react until the carbonation rate becomes 50 to 85%, then 1 to 20% by volume of the calcium hydroxide slurry is added, and carbon dioxide containing gas is further blown in to terminate the reaction. The calcium carbonate obtained by this method is precipitated calcium carbonate aggregates having a secondary particle diameter of 1 to 10 ?m and consisting of primary particles having a long diameter of 0.5 to 3.0 ?m, a short diameter of 0.1 to 1.0 ?m and an aspect ratio of 3 or more, has superior characteristics due to a BET specific surface area in the range of 8 to 20 m2/g and a pore volume in the range of 1.5 to 3.5 cm3/g, can be uniformly dispersed in pulp fiber, and thereby can be used to manufacture high bulk paper.

Abstract: The light calcium carbonate in the form of microparticle aggregate of the present invention has a BET specific surface area not smaller than 10 m2/g and not larger than 25 m2/g, a pore volume of 0.05 cm3/g or larger for pores having a pore diameter of 0 to 1000 ? as determined by the nitrogen adsorption method, and a pore volume ratio of 25% or more for pores having a pore diameter of 250 ? or smaller based on the total pore volume as determined by the nitrogen adsorption method, and shows an oil absorption of 100 cc/100 g or more as determined by using liquid paraffin. By using this light calcium carbonate as a filler of printing paper, superior ink absorbing property and opacity (especially opacity after printing) can be imparted to the printing paper.

Abstract: A coating solution comprising: (A) an aragonite-type light calcium carbonate microparticle having an average major axis diameter of 1.0 to 2.8 ?m and an average minor axis diameter of 0.15 to 0.3 ?m, which is produced by diluting a calcium hydroxide slurry that has been treated by high-speed shearing until the slurry has a viscosity of 1000 cP or more at a concentration of 400 g/l to a concentration more than 50 g/l and then blowing carbon dioxide into the diluted slurry at a reaction starting temperature of 20 to 60° C. and at a rate of 1 to 3 l/min per kg of calcium hydroxide; and (B) a pigment comprising a wet heavy calcium carbonate cake. The coating solution enables to provide a coated paper having an excellent degree of brilliance and an excellent degree of whiteness, despite containing no kaolin.

Abstract: Carbon dioxide containing gas is blown into a calcium hydroxide slurry having a calcium hydroxide concentration of 100 to 400 g/L obtained by wet slaking calcined lime with 4 N hydrochloric acid activity (value at 3 minutes) of 150 to 400 mL to allow them to react until the carbonation rate becomes 50 to 85%, then 1 to 20% by volume of the calcium hydroxide slurry is added, and carbon dioxide containing gas is further blown in to terminate the reaction. The calcium carbonate obtained by this method is precipitated calcium carbonate aggregates having a secondary particle diameter of 1 to 10 ?m and consisting of primary particles having a long diameter of 0.5 to 3.0 ?m, a short diameter of 0.1 to 1.0 ?m and an aspect ratio of less than 3, has superior characteristics due to a BET specific surface area in the range of 8 to 20 m2/g and a pore volume in the range of 1.5 to 3.5 cm3/g, can be uniformly dispersed in pulp fiber, and thereby can be used to manufacture high bulk paper.

Abstract: A flower container has a control unit (14) comprising a water sensor (20) for directly or indirectly detecting water content in soil in a flowerpot (12), a memory (22) storing at least first and second recorded messages, and a speaker (32). When receiving a detection signal from the water sensor which indicates that the water content is decreased to below a predetermined level, the first message is read out from the memory and outputted through the speaker to urge a user to supply water. When the detection signal from the water sensor indicates that the water content is returned to above the predetermined level within a predetermined period of time from reproduction of the first message, the second message is read out from the memory and outputted through the speaker in appreciation of user's watering.

Abstract: A calcium-magnesium carbonate composite consisting of particles of calcium carbonate and magnesium carbonate hydroxide and having excellent properties, for example, as a pigment for paper coating is proposed, which is a uniform blend of:(A) particles of calcium carbonate having a crystalline structure of aragonite with a columnar particle configuration having a length in the range from 0.5 to 3 .mu.m and a diameter in the range from 0.1 to 0.3 pm with an aspect ratio in the range from 5 to 15; and(B) particles of magnesium carbonate hydroxide having a plate-like particle configuration with a particle diameter in the range from 2 to 7 .mu.m and a thickness in the range from 0.05 to 0.5 .mu.m,the blend having an overall specific surface area in the range from 15 to 30 m.sup.2 /g and the weight proportion of the particles of calcium carbonate to the particles of magnesium carbonate hydroxide being in the range from 95:5 to 50:50 calculated as the respective hydroxides.

Abstract: An improved method for manufacturing a magnet paper sheet which comprises: thoroughly mixing about 70-90 parts by weight of magnetoplumbite barium ferrite powder and/or magnetoplumbite strontium ferrite powder essentially consisting of particles of primary particle size of about 0.1-2 microns and of secondary particle size smaller than about 20 microns, an anionic synthetic latex containing about 1-10 parts by weight in dry weight of a synthetic rubber and/or a synthetic resin such as SBR, NBR, polyvinyl acetate and polyacrylate, about 2-10 weight % of a cationic organic polymer electrolyte such as polyamine and polyethyleneimine based on the amount of the synthetic rubber and/or resin, and more than about 5 parts by weight of pulp fibers together into a slurry; forming the slurry into a paper sheet; and magnetizing the paper sheet.