Abstract: A lithium niobate solution is provided containing lithium niobate having a molar ratio of lithium and niobium Li/Nb of 0.8 or more and 2.0 or less and ammonium ions, and the particle size (D50) of the lithium niobate in the lithium niobate solution according to dynamic light scattering is 100 nm or less. A method for producing a lithium niobate solution is also provided and has a step of producing an acidic niobium solution containing niobium, a step of obtaining a precipitate slurry containing niobium by inverse neutralization by adding the acidic niobium solution to ammonia water and a step of obtaining a lithium niobate solution by maintaining a mixture of the precipitate slurry containing niobium and lithium hydroxide at 20° C. to 100° C. with stirring.

Abstract: A polyoxo niobate compound dispersion is provided and includes a part or all of a polyoxo niobate compound dispersed or dissolved in a mixed solvent using a lower alcohol and water as a main solvent and containing a primary amine, a secondary amine, a tertiary amine, a quaternary ammonium compound, or two or more of them, wherein the content of water is 5.0% by mass or more, the content of the amine compound solvent is 0.50 or more in terms of a molar ratio relative to the content of niobium (Nb), and the lower alcohol accounts for 70% by mass or more of a contained component other than a component derived from the polyoxo niobate compound, a component derived from the amine compound solvent, and water.

Abstract: A niobate compound is provided that has excellent reactivity with alkali metal salts and can be reacted with alkali metal salts at room temperature. The niobate compound has a ratio (first peak/second peak) of the intensity of a peak (first peak) having the highest intensity at 2?=9.4°±1.5° to the intensity of a peak (second peak) having the highest intensity at 2?=29.0°±1.5° being 1.3 or more in the X-ray diffraction pattern.

Abstract: A niobic acid aqueous solution is provided having higher dispersibility than an ammonium niobate sol and having better solubility than a complex salt of niobic acid. The niobic acid aqueous solution contains 0.1 to 40 mass % of niobium in terms of Nb2O5, wherein no particles of 1.0 nm or more are detected in the particle size distribution measurement using dynamic light scattering. A method for producing the same includes adding a niobium fluoride aqueous solution containing 1 to 100 g/L of niobium in terms of Nb2O5 to an ammonia aqueous solution having an ammonia concentration of 20 to 30 mass % and reacting them, removing fluorine from the obtained reaction solution, and adding at least one selected from amines and ammonia to the obtained solution and reacting them.

Abstract: A prepreg lamination head and a prepreg automatic lamination apparatus with the same is provided. By using them, the curling-up of the cut terminal portion of the prepreg sheet can be prevented. The prepreg lamination head includes: a first roller, a second roller, and a forward-placed paper liner peeling device. The forward-placed paper liner peeling device includes a third roller, which is provided between and above the first and second rollers. The paper liner attached on the first side of the prepreg sheet is peeled off right after passing the first roller. The peeled paper liner is hanged over the third roller between the first and second rollers. The third roller guides the peeled paper liner to the second roller. The prepreg sheet is pressed on the laminated body with the second roller through the paper liner.

Abstract: A prepreg lamination head which laminates a prepreg sheet (8) toward a fiber direction (T2) in a direction intersecting a length direction (T1) of a prepreg laminated body is disposed at each of both outsides oldie subject laminated body (W) in the width direction. The prepreg lamination head includes: a pair of guide rollers which guides a prepreg sheet (8) so as to be superimposed on the subject laminated body (W); and a lamination shoe (31) which is disposed between the pair of guide rollers so as to freely advance and retract in the fiber direction (T2) and stick the prepreg sheet (8) guided between the pair of guide rollers on the subject laminated body (W) by pressing the prepreg sheet from one surface thereof. Then, the lamination shoe (31) is divided in the width direction of the prepreg sheet (8).

Abstract: A prepreg lamination head and a prepreg automatic lamination apparatus with the same is provided. By using them, the curling-up of the cut terminal portion of the prepreg sheet can be prevented. The prepreg lamination head includes: a first roller, a second roller, and a forward-placed paper liner peeling device. The forward-placed paper liner peeling device includes a third roller, which is provided between and above the first and second rollers. The paper liner attached on the first side of the prepreg sheet is peeled off right after passing the first roller. The peeled paper liner is hanged over the third roller between the first and second rollers. The third roller guides the peeled paper liner to the second roller. The prepreg sheet is pressed on the laminated body with the second roller through the paper liner.