US 5,997,836 A · Alkali aluminum complex hydroxide carbonate salt, and a process for producing said salt and its uses

Abstract

According to this invention, an amorphous or pseudo-boehmite-type hydrated alumina gel and an alkali metal carbonate or bicarbonate as starting materials are reacted in an aqueous medium to give a method of producing a process for producing an alkali aluminum complex hydroxide carbonate salt which is industrially low-cost and has high productivity. Furthermore, by using a gibbsite-type hydrated alumina, a lithium aluminum complex hydroxide carbonate salt can be synthesized by a migration method. The lithium aluminum complex hydroxide carbonate salt and the sodium aluminum complex hydroxide carbonate salt obtained by the processes of the present invention have excellent compoundability in pigments and resins. In addition, these complex salts have no foaming hazards at the time of processing the resins and are useful as resin fillers for halogen capturing property, infrared ray absorbing property and excellent transparency. They are especially useful as a stabilizer (halogen capturing agent) for resin films, a warmth-keeping agent (infrared absorbing agent) and an anti-blocking agent.

Claims14

Dependent claims

A process for producing a lithium aluminum complex hydroxide carbonate salt, which comprises reacting amorphous or pseudo-boehmite hydrated alumina gel and a lithium carbonate or bicarbonate in an aqueous medium under such a condition that the concentration of aluminum, calculated as alumina (Al.sub.2 O.sub.3), based on the total amount of the aqueous medium and the materials added to the aqueous medium, becomes 1 to 5% by weight, and the pH at the termination of the reaction becomes 7 to 11,

wherein the hydrated alumina is reacted with the carbonate or the bicarbonate so that the amount of the carbonic acid ion is at least 0.25 mole based on the total aluminum atoms and
wherein the reaction is carried out at a temperature of 50 to 90.degree. C.

A lithium aluminum complex hydroxide carbonate salt which has a composition represented by formula (6a)

mAl.sub.2 O.sub.3.nM.sub.2 O.X.kH.sub.2 O (6a)
wherein X represents an inorganic anion composed mainly of a carbonic acid radical, M represents an alkali metal composed mainly of lithium, m is a number from 1.5 to 2.5, n is a number from 0.1 to 1, and k is a number from 0 to 10,
and which has an X-ray diffraction pattern shown below
______________________________________ Spacing d (A) Index of a plane Peak intensity ______________________________________ 7.50 to 7.64 Large (002) 4.30 to 4.44 Small (110) 3.70 to 3.84 Large (004) 2.45 to 2.58 Medium (006) 2.20 to 2.30 Small (016) 1.85 to 2.08 Small (017) 1.40 to 1.52 Small (330) 1.38 to 1.48 Small (600) ______________________________________
the lamination asymmetry index (Is) being defined by
Is=tan .theta..sub.2 /tan .theta..sub.1 ( 7)
wherein .theta..sub.1 represents an angle formed between a peak perpendicular and a peak tangent on the narrow angle side at an X-ray diffraction peak of a fixed spacing, and .theta..sub.2 represents an angle formed between the peak perpendicular and a peak tangent on the wide angle side at the peak,
and the Is being 1.0 or below at the peak of an index of a plane (016) and 1.0 or below at the peak of an index of a plane (017).

5 more elements

Dependencies are inferred from the claim text.

Alkali aluminum complex hydroxide carbonate salt, and a process for producing said salt and its uses

Life of this patent

Alkali aluminum complex hydroxide carbonate salt, and a process for producing said salt and its uses

Life of this patent

Abstract

Claims14