Fiber-containing roof tile, molding material for producing fiber-containing roof tile, and process for producing same

Patent metadata

Field	Value
Publication number	US-10604447-B2
Application number	US-201515539385-A
Country	US
Kind code	B2
Filing date	Dec 24, 2015
Priority date	Dec 26, 2014
Publication date	Mar 31, 2020
Grant date	Mar 31, 2020

Abstract

A roof tile containing fibers which satisfy the following requirements (1) to (3):
(1) to have an average fiber diameter of 50 μm or less; (2) to have an aspect ratio of 50 to 2000; and (3) to have three or less buckled portions per fiber.

First claim

What is claimed is:

1. A roof tile, comprising fibers satisfying the following requirements (1) to (3):
(1) having an average fiber diameter of 50 μm or less;
(2) having an aspect ratio of 50 to 2000; and
(3) having three or less buckled portions per fiber.

2. The roof tile according to claim 1 , wherein:
the roof tile has an upper surface hardened by non-mold shaping, a lower surface hardened by mold shaping, and side surfaces; and
the roof tile has a cut end surface on at least one of the side surfaces.

3. The roof tile according to claim 2 , comprising at least one selected from the group consisting of a polyvinyl alcohol-based fiber, a polyethylene fiber, a polypropylene fiber, an acrylic fiber and an aramid fiber.

4. The roof tile according to claim 1 , wherein a 30 mm×150 mm cut piece of the roof tile has a bending strength of 5 N/mm 2 or higher.

5. The roof tile according to claim 1 , wherein the fibers are optionally present as fiber agglomerates, and a content of the fiber agglomerate having an equivalent circle diameter of 3 mm or more is 25% by weight or less relative to the total content of the fibers.

6. The roof tile according to claim 1 , wherein a CV value as dispersion variance of the fibers is 35% by weight or less.

7. The roof tile according to claim 1 , wherein the roof tile has a content of the fibers of from 0.1 to 2% by weight.

8. The roof tile according to claim 1 , wherein the fibers are at least one selected from the group consisting of a polyvinyl alcohol-based fiber, a polyethylene fiber, a polypropylene fiber, an acrylic fiber and an aramid fiber.

9. The roof tile according to claim 1 , wherein:
the roof tile comprises a fine aggregate; and
the fine aggregate has an average particle diameter of from 0.1 to 5 mm.

10. A molding material for producing the roof tile according to claim 1 , the molding material comprising at least cement, a fine aggregate, fibers and water,
wherein the fibers are optionally present as fiber agglomerates, and a content of the fiber agglomerate having an equivalent circle diameter of 3 mm or more is 25% by weight or less relative to the total content of the fibers.

11. A process for producing the roof tile according to claim 1 , the process comprising:
adding the fibers into a mixture comprising cement, a fine aggregate and water at an addition rate of 5 kg/sec or less per ton of solid content of the mixture and simultaneously dispersing the fibers to obtain a molding material;
supplying the molding material into a hopper of a roller/slipper type extrusion device;
filling a plurality of adjacent pallets with the supplied molding material from a lower side of the hopper;
compressing the molding material with a roller and a slipper to form a continuous band on the pallets;
cutting the band with a cutting blade to form individual unhardened roof tiles on the individual pallets; and
hardening the unhardened roof tiles.

12. The process according to claim 11 , wherein the fibers added into the mixture are optionally present as fiber agglomerates and a content of the fiber agglomerates having an equivalent circle diameter of 3 mm or more is 25% by weight or less relative to the total content of the fibers.

13. The process according to claim 11 , wherein a CV value as dispersion variance of the fibers in the molding material obtained in said adding is 35% by weight or less.

14. The process according to claim 11 , wherein:
the fibers are subjected to disaggregation treatment and then added into the mixture; and
the disaggregation treatment is at least one treatment selected from the group consisting of a treatment of passing the fibers between facing rotation gears to disaggregate the fibers; a treatment of hooking the fibers on a roll having protrusions to disaggregate the fibers; a treatment of disaggregating the fibers by a shearing force of a rotary disk having a groove; and a treatment of disaggregating the fibers by a collision force of air flow.

Assignees

• Kuraray Co

Inventors

• Imagawa Akira
• Inada Shinya
• Iwasaki Yoshihiro
• Hada Saburo

Classifications

• B28B5/028

  the moulding surfaces being of definite length, e.g. succession of moving pallets, and being continuously fed (feeding B28B13/02) · CPC title

• B28B3/123

  on material in moulds or on moulding surfaces moving continuously underneath or between the rollers, e.g. on an endless belt · CPC title

• B28B1/52

  specially adapted for producing articles from mixtures containing fibres, {e.g. asbestos cement}(by wrapping on to mandrels B28B1/42) · CPC title

• C04B2111/00594

  Concrete roof tiles · CPC title

• C04B2111/40

  Porous or lightweight materials · CPC title