US 10,894,907 B2 · Latent-heat storage body microcapsules and process for producing latent-heat storage body microcapsules

Abstract

In the present invention, after a primary coating film is formed by boehmite treatment of the surface of a core particle in a solution comprising Al ions, a secondary coating film is formed by cooling the solution to the supersaturation temperature of the Al ions to cause deposition of a hydroxide of aluminum on the surface of the primary coating film, and an Al oxide film is formed on the surface of the core particle by heat treating the secondary coating film in an oxidizing atmosphere. Consequently, the shell is thickened by the amount of secondary coating film formed, so that the cyclic strength of the capsule can be secured and the composition change of the PCM in the production process is remarkably suppressed.

Claims5

Dependent claims

A latent heat storage body microcapsule comprising a core particle of latent heat storage material with a surface coated with an oxide film,

the oxide film comprising a first oxide film directly covering the surface of the core particle, a second oxide film covering the first oxide film, and a third oxide film covering the second oxide film,
the first oxide film being a non-porous dense oxide film comprising α-Al2O3,
the second oxide film being a porous oxide film, and an X ray diffraction analysis of the second oxide film showing only peaks corresponding to α-Al2O3, and
the third oxide film being a porous oxide film in which α-Al2O3 and θ-Al2O3 are present mixedly, having a structure different from that of the second oxide film.

1 more element

Dependencies are inferred from the claim text.

Facts

Application

16/302,354Filed 17 May 2017

Priority

JP 2016-09881517 May 2016

Published

US 2019/0300770 A13 Oct 2019

Granted

19 Jan 2021

Term ends

Not estimatedThe source records don’t support an estimate.

Classification22 codes

C09K 5/063
The change of state being from liquid to solid or vice versa: materials absorbing or liberating heat during crystallisation; Heat storage materials
B22F 1/00
Metallic powder
B22F 1/16
Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties: metallic particles coated with a non-metal
C09K 5/06
Materials undergoing a change of physical state when used: the change of state being from liquid to solid or vice versa

Latent-heat storage body microcapsules and process for producing latent-heat storage body microcapsules

Life of this patent

Latent-heat storage body microcapsules and process for producing latent-heat storage body microcapsules

Life of this patent

Abstract

Claims5