Compositions, panels and sheets comprising mineral fillers and methods to produce the same

Patent metadata

Field	Value
Publication number	US-2016102018-A1
Application number	US-201514876244-A
Country	US
Kind code	A1
Filing date	Oct 6, 2015
Priority date	Oct 10, 2014
Publication date	Apr 14, 2016
Grant date	—

Abstract

There are provided gypsum panels, sheets and multi-layer sheets as well as methods of preparation thereof. For example, there are provided cellulose filament-reinforced gypsum panels, sheets and multi-layer sheets and methods of preparation thereof. For example, in such gypsum panels, sheets and multi-layer sheets gypsum is bound with cellulose filaments to strengthen the gypsum panels, sheets and multi-layer sheets. The cellulose filament-reinforced gypsum panel can be, for example, a core comprising a honeycomb or corrugated structure. There are also provided aqueous suspensions comprising cellulose filaments and CaSO 4 .2H 2 O.

First claim

What is claimed is:

1 . A sheet comprising cellulose filaments and CaSO 4 .2H 2 O, said sheet comprising at least about 0.1% of cellulose filaments by weight, based on the total weight of the cellulose filaments and the CaSO 4 .2H 2 O.

2 . The sheet of claim 1 , wherein said sheet comprises at least about 1% of cellulose filaments by weight, based on the total weight of the cellulose filaments and the CaSO 4 .2H 2 O.

3 . The sheet of claim 2 , wherein said sheet comprises at least about 5% of cellulose filaments by weight, based on the total weight of the cellulose filaments and the CaSO 4 .2H 2 O.

4 . The sheet of claim 2 , wherein said sheet comprises at least about 15% of cellulose filaments by weight, based on the total weight of the cellulose filaments and the CaSO 4 .2H 2 O.

5 . The sheet of claim 2 , wherein said sheet comprises about 5% to about 30% of cellulose filaments by weight, based on the total weight of the cellulose filaments and the CaSO 4 .2H 2 O.

6 . The sheet of claim 2 , wherein said sheet comprises at least about 50 wt % of CaSO 4 .2H 2 O, based on the total dry weight of the sheet.

7 . The sheet of claim 5 , wherein said sheet comprises about 70 wt % to about 85 wt % of CaSO 4 .2H 2 O, based on the total dry weight of the sheet.

8 . The sheet of claim 5 , wherein said sheet has a basis weight of about 60 g/m 2 to about 2400 g/m 2 .

9 . The sheet of claim 2 , wherein said sheet has a density of about 0.5 g/cm 3 to about 0.8 g/cm 3 .

10 . The sheet of claim 2 , wherein said sheet has a density of about 0.9 g/cm 3 to about 1.3 g/cm 3 .

11 . The sheet of claim 8 , wherein said sheet has a thickness of about 0.15 mm to about 0.40 mm.

12 . The sheet of claim 2 , wherein said sheet has a tensile index of at least about 2 N·m/g when measured according to TAPPI T494 om—01.

13 . The sheet of claim 5 , wherein said sheet has a tensile index of from about 1 N·m/g to about 20 N·m/g when measured according to TAPPI T494 om—01.

14 . The sheet of claim 2 , wherein said sheet has been made on a paper machine.

15 . The sheet of claim 5 , wherein said cellulose filaments have an average length of from about 200 μM to about 2 mm and an average width of from about 30 nm to about 500 nm.

16 . A multi-layer sheet comprising cellulose filaments and CaSO 4 .2H 2 O, said multi-layer sheet comprising at least two sheets as defined in claim 2 .

17 . The multi-layer sheet of claim 16 , wherein said multi-layer sheet has a flexural strength of from about 5 MPa to about 35 MPa when measured according to ASTM D790.

18 . A gypsum panel comprising a first multi-layer sheet, a second multi-layer sheet and a core comprising a honeycomb or corrugated structure sandwiched between said first multi-layer sheet and said second multi-layer sheet, said first multi-layer sheet, said second multi-layer sheet and said honeycomb or corrugated structure each comprising cellulose filaments and CaSO 4 .2H 2 O.

19 . A method for preparing a cellulose filament-reinforced (CF-reinforced) gypsum sheet, said method comprising:
draining an aqueous suspension comprising cellulose filaments and CaSO 4 .2H 2 O under conditions to obtain a wet fiber mat; pressing said wet fiber mat under conditions to remove water and obtain a pressed sheet; and drying said pressed sheet under conditions to obtain said CF-reinforced gypsum sheet.

20 . The method of claim 19 , wherein said method is a method for preparing a CF-reinforced gypsum handsheet, and said method comprises:
adding an aqueous suspension comprising cellulose filaments and CaSO 4 .2H 2 O to a deckle under conditions to obtain said wet fiber mat; pressing said wet fiber mat with a manual roll under conditions to remove water and obtain a pressed sheet; optionally repeating said pressing; and drying said pressed sheet using a dryer under conditions to obtain said CF-reinforced gypsum sheet.

21 . The method of claim 20 , wherein said method comprises using a paper machine, and said method comprises:
adding an aqueous suspension comprising cellulose filaments and CaSO 4 .2H 2 O to a forming section of said paper machine under conditions to obtain a wet fiber web; pressing said wet fiber web with a press section of said paper machine under conditions to obtain a pressed web; and drying said pressed web under conditions to obtain said CF-reinforced gypsum sheet.

22 . A cellulose filament (CF)-reinforced gypsum sheet prepared according to the method of claim 21 .

23 . An aqueous suspension comprising cellulose filaments and CaSO 4 .2H 2 O.

24 . The aqueous suspension of claim 23 , wherein the ratio by weight of said cellulose filaments to said CaSO 4 .2H 2 O is from about 1:99 to about 50:50.

25 . The aqueous suspension of claim 24 , wherein said aqueous suspension has a consistency of from about 1 wt % to about 20 wt %.

Assignees

• Fpinnovations

Inventors

• Dorris Gilles
• Ben Yuxia
• An Qiaozhi
• Dorris Annie
• Wang Xiaoyu

Classifications

• B32B2307/718

  Weight, e.g. weight per square meter · CPC title

• B32B13/02 Primary

  with fibres or particles {being present as additives in the layer} · CPC title

• C04B16/02 Primary

  Cellulosic materials (cellulosic waste materials, e.g. sawdust, rice husks, C04B18/24) · CPC title

• B32B13/04

  comprising such {water setting} substance as the main or only constituent of a layer, {which is} next to another layer of {the same or of} a {different material (next to a glass layer B32B17/06)} · CPC title

• B32B2307/72

  Density · CPC title