A process is provided for the preparation of lacing resistant, titanium dioxide particles for use in photodurable thin film production. Said process involves dewatering titanium dioxide particles that have been encapsulated with a layer of amorphous alumina in continuous fashion at temperatures in excess of 100° C.

The present invention relates to a grinding aid as well as a grinding method. Further, the present invention pertains to a titanium dioxide particle with a layer comprising a grinding aid as described herein and the use of said titanium dioxide particle in various applications.

The disclosure relates to a conductive particle and a manufacturing method thereof, an adhesive and an application thereof. The conductive particle includes a core, a conductive carbon layer and a conductive polymer layer. The conductive carbon layer covers the core, and the conductive polymer layer is provided on the conductive carbon layer. The conductivity of the conductive particle is higher.

Providing a white pigment dispersion that shows good storage stability because the white pigment contained therein is less likely to sediment, an ink composition comprising the white pigment dispersion, and a method of image formation using the ink composition. A white pigment dispersion comprising at least a specified white pigment, a polymeric dispersant, and an aqueous liquid as a solvent or dispersion medium, wherein; the specified white pigment is a titanium dioxide that has been surface-treated with at least alumina, the polymeric dispersant has a structure with a principal chain having a pigment adsorption group and a water-soluble molecular chain grafted to the principal chain, the overall weight-average molecular weight of the polymeric dispersant is in the range of 2000 to 50000, the weight-average molecular weight of the graft chain is in the range of 150 to 3000, and the difference between the lightness value L of the coating film from the pre-centrifugation white pigment dispersion and the lightness value L of the coating film from the post-centrifugation supernatant liquid is less than 25.

In producing titanium oxide containing rutile-type crystals by adding hydrochloric acid to an aqueous dispersion of an alkali metal titanate, sulfurous acid, disulfurous acid, sulfuric acid or a salt thereof is added. Thus, there is provided a titanium oxide powder which is doped with bivalent sulfur atoms (S.sup.2−) and in which a ratio (I.sub.A/I.sub.R) of a peak intensity (I.sub.A) of anatase-type crystals to a peak intensity (I.sub.R) of rutile-type crystals as measured by X-ray diffractometry is 0.1 or less. Moreover, a cosmetic is provided by dispersing the titanium oxide powder in a dispersion medium. Thus, bluish color derived from Rayleigh scattering is negated, providing a dispersion, particularly a cosmetic, with excellent transparency and color tone.

A method of treating particulate titanium dioxide includes providing the particulate titanium dioxide which includes a crystal structure and then treating the particulate titanium dioxide with a coating agent that is an alkylphosphonic acid or an ester thereof, and steam micronizing the particulate titanium dioxide with a steam micronizer so that a vapor exit temperature from the steam micronizer is 150° C. or higher, so as to obtain a micronized particulate titanium dioxide which includes the coating agent at an outer surface. The particulate titanium dioxide includes an aluminum oxide coating and/or includes within the crystal structure aluminum oxide in a molar excess of an amount required to compensate any Nb.sub.2O.sub.5 in the crystal structure. The alkylphosphonic acid includes a C.sub.6-C.sub.22 alkyl group.

In an ultraviolet-shielding particle coated with silicon oxide of the present invention, a surface of the ultraviolet-shielding particle is coated with a silicon oxide coat, at least one functional group selected from the group consisting of an alkyl group, an alkenyl group, and a cycloalkyl group is present on a surface of the silicon oxide coat, and a content of the functional group is 0.0001% by mass or more and 0.30% by mass or less.

An inorganic pigment which is treated with at least one non-reactive polysiloxane of the general Formula I

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In general Formula I, R.sup.1 to R.sup.8 are the same or different and are selected from C.sub.mH.sub.2m+1, wherein m is ≤10, and fluorinated derivatives thereof wherein at least one hydrogen atom is replaced by fluorine, C.sub.6H.sub.5, and (EO).sub.x(PO).sub.y and copolymers thereof, wherein EO is an oxyethylene unit, PO is an oxypropylene unit, x and y are the same or different, and x+y is in the range of 1 to 50. The at least one non-reactive polysiloxane has a viscosity in the range of 50-3000 mm.sup.2×s.sup.−1 at 25° C. The inorganic pigment treated with the at least one non-reactive polysiloxane of general Formula I has a residual moisture content of less than 1 wt-%.

Process for the surface treatment of a titanium dioxide pigment, characterized in that it comprises the following steps: an aqueous suspension of titanium dioxide pigments is formed, in a first step, a layer of alumina phosphate is precipitated on the surface of the pigment, in a second step, a layer of alumina is precipitated over the first layer of alumina phosphate, and in an optional third step, a layer of magnesium oxide is precipitated on the layer of alumina Titanium dioxide pigments made by the disclosed process and method using said pigments in paper manufacturing are also disclosed.

Process for the surface treatment of a titanium dioxide pigment, characterized in that it comprises the following steps: an aqueous suspension of titanium dioxide pigments is formed, in a first step, a layer of alumina phosphate is precipitated on the surface of the pigment, in a second step, a layer of alumina is precipitated over the first layer of alumina phosphate, and in a third step, a layer of magnesium oxide and alumina is precipitated on the layer of alumina. Also included are titanium dioxide pigments made by the disclosed process and method using said pigments in paper manufacturing.