WO2014158104A2

WO2014158104A2 - Sheets with organic filler

Info

Publication number: WO2014158104A2
Application number: PCT/TH2014/000011
Authority: WO
Inventors: Prakan LEERAPONGNUN; Teerapun RASSAMEKIARTISAK; Chairat PONGTONGCHAROEN; Siriluk PONGKEATCHAI; Somchai PATTANAVIJIT; Thipnakarin BOONFUENG; Suwarat RAKCHOY
Original assignee: Siam Kraft Industry Co., Ltd.
Priority date: 2013-03-29
Filing date: 2014-03-28
Publication date: 2014-10-02
Also published as: WO2014158104A3

Abstract

The present invention relates to sheet with organic filler comprising a fibrous portion and an organic filler wherein; the organic filler consists of solid component and moisture and; the solid component in the organic filler comprises at least 15% of fibrous portion of a sac shape containing starch. It is found that the sheet having a high amount of such organic filler can maintain the desired mechanical characteristics and can reduce the cost of production as well.

Description

SHEETS WITH ORGANIC FILLER

Field of the Invention

This invention relates to sheet with organic filler.

Background of the Invention

Sheets or sheet materials consist of two parts: the fiber section, which is the main structure of the sheet. The fibrous portion is generally presents from 70-95 % by weight of the sheet depending on the type of sheet to be produced. The fibers used are often natural fibers (such as fibers from plant, fibers from animal or mineral fibers) or synthetic fibers (such as polyamide). In the case where used sheets themselves are used as raw material in the production of sheet for efficiency reasons, a suitable additive is used as the second part in manufacturing sheets to improve their properties to suit the intended use. There are various types of additives such as anti- seepage, filler, thickener, dye, bleach, anti-lathering agent, microbial control agent, dispersants, etc.

Additives commonly used are fillers, which increase optical properties and improve printing characteristics of the sheet. Using fillers also helps to reduce production costs of sheets because they are cheaper compared to fibers. Fillers can be divided into two main categories; organic fillers such as starch and starch derivatives which increase the strength of sheets and; inorganic fillers such as kaolin, talc, calcium carbonate, titanium dioxide which increase the smoothness, shininess, printability, opacity, brightness, etc.

The filler which is suitable and commonly used for the paper or sheet or sheet material manufacturing technology is kaolin as its flake or sheet shaped particles aligned in the same direction in an orderly manner gives the paper or sheet or sheet material a high gloss and smoothness. Patent application No. WO 2005/124021 discloses that kaolin can be added up to 30 % or more during the manufacturing process. However, excessively high quantity of kaolin can lead to the decreased strength of the paper or sheet or sheet material. Kaolin's presence at 10 % can cause the strength of the paper or sheet or sheet material to decrease by 20 %. It is also the cause of linting and dusting of the sheets or sheet materials which will reduce the printing quality due to the inadequate binding of the fibers and the fillers to the sheet. In addition, a study of certain properties of paper, conducted by Se- Young Yoon in May 2007, shows that the tensile index, the burst strength and the folding endurance tends to decrease with the addition of the inorganic filler of clay types. Table 1 The changes of tensile index, bursting strength and folding endurance values at different ratios of clay addition.

Another suitable organic filler for the manufacturing of paper or sheet or sheet material is starch which may be selected from starch of various types such as corn starch, potato starch, cassava starch, wheat starch, etc. The quantity of starch varies in each type of paper or sheets or sheet materials. In some types of paper or sheets or sheet materials, starch may be present up to 10 % by weight of the paper or sheets or sheet materials. In most manufacturing process, starch is added during three steps which can be all three steps or two of these three steps or one of these three steps; the wet process to increase strength to the paper or sheets or sheet materials; the rendering the surface of paper or sheets or sheet materials smooth and; the coating of paper or sheets or sheet materials to increase water resistance. Moreover, another function of starch as a thickener is well known and has been used for a long time. However, currently, a mix of cationic starch and polyacrylamide is preferred because the cations in such mix bind well with the anionic fibers, resulting in a paper or sheet or sheet materials with increased strength.

The patent application No. WO 2012076163 A2 discloses wheat starch improvement by cationizing and crosslinking to improve the strength of the paper or sheets, especially in the wet stages of the production process.

The patent application No. WO 2009079268 Al discloses a coating composition suitable for paper production. Such composition comprises starch and one or more additional components selected from the group consisting of amphoteric surfactant, emulsion particles and combination thereof. Paper coated with such compositions is used as packaging for relatively highly greasy food.

European patent application No. EP 2148003 Al discloses a process for producing products comprising modified starch and resin such as polyaminoamide epichlorohydrin which increases dry strength of the paper product.

Japanese patent application No. JP2009243013A discloses the paper coated with potato starch having amylose pectin ratio of 95 % by weight or more, based on the paper with calcium carbonate, 0.1 to 3.0 g / M resulting in paper with excellent printing characteristics.

However, it was found that the amount of fillers (e.g. starch) to be added in the production process of the paper or sheets or sheet materials is not high because the increased amount of filler can adversely affect certain properties of the paper or sheets or sheet materials such as mechanical, printing properties, etc. In some cases, increasing the amount of fillers means increasing the cost of production as well. For all types of paper or sheets or sheet materials, it is important to add the highest amount of fillers while maintaining the appropriate strength for each type of paper or sheets or sheet materials, sufficient drainage and filler retention of the final product of paper or sheets or sheet materials.

Summary of the Invention

This invention relates to sheets with organic filler (e.g. starch) derived from agricultural materials. The organic filler comprises solid component and moisture wherein the solid component of the organic filler comprises at least 70 % of fibrous portion having sac shape containing the grains of starch.

The object of this invention is to prepare a sheet with higher amount of organic filler wherein desired mechanical properties are maintained, which also minimize the cost of production.

Brief Description of the Drawings

Figure 1 shows a 50x magnified image of fibrous portion having sac shape containing the grains of starch. Detailed Description of the Invention

The following and other features and advantages will be apparent for those ordinarily skilled in the art from reading the following description of the invention. For the avoidance of doubts, any characteristics of the present invention may be used in any other aspect of the invention.

In general, organic fillers commonly used in the production of sheets or sheet materials can be prepared from agricultural materials or agricultural wastes such as cassava, potato, sweet potato, sago, taro, yam and so on.

The organic filler of the present invention consists of two parts; the solid component and moisture. The solid component has a starch portion of 30-90 % by weight of the total weight of solid component.

In an aspect of the present invention, the solid component of the organic filler comprises at least 15 % of short fibrous portion having a sac shape containing grains of starch (Fig. 1).

The average particle size of the organic filler is preferably in the range of 100-500 microns, more preferably in the range of 250-450 microns, more preferably in the range of 125-

350 microns, more preferably in the range of 150-300 microns and most preferably in the range of 150-250 microns.

In the present invention, the organic filler having the above-described characteristics, i.e. consisting of the fibrous portion of a sac shape containing grains of starch wherein such portion is present at least 15 %, is added during the manufacturing process of sheets or sheet materials.

It was found that the sheet or the sheet material containing the above-described filler managed to maintain the desired mechanical properties with the addition of organic additives in a higher amount.

In the context of the present invention, the term "sheet" includes material that has a sheet shape consisting of fibers and natural polymeric material, particularly, materials with a sheet shape consisting predominantly of cellulose fibers such as paper, etc.

In an embodiment of the present invention, it is found that the sheet having at least 5% by weight of the organic filler of the present invention, the ring crush resistance (RCT) according to ISO 12192 standard increased at least by 10 % compared to the sheet without the organic filler of the present invention. In another embodiment of the present invention, it is found that in the sheet with at least 3 % by weight of the organic filler of the present invention, the crush resistance, from the Corrugated Medium Test (CMT) according to the ISO 7263 standard, increased at least by 10 % compared to the sheet without the organic filler of the present invention. In yet another embodiment of the present invention, it is found that in the sheet having at least 5% by weight of the organic filler of the present invention, the compression resistance, from the Short Span Compression Test (SCT) according to ISO 9895 standard, increased at least by 5 % compared to the sheet without the organic filler of the present invention.

In yet another embodiment of the present invention, it is found that in the sheet having at least 5% by weight of the organic filler of the present invention, the burst strength, from the test according to ISO 2759 standard, increased at least by 5 % compared to the sheet without the organic filler of the present invention.

In yet another embodiment of the present invention, it is found that in the sheet having at least 5% by weight of the organic filler of the present invention, the folding endurance from the test according to ISO 5626 standard increased by at least 10 % compared to the sheet without the organic filler of the present invention.

Following the invention will be illustrated by means of non-limiting examples. It is to be understood that the following examples are provided for illustrative purposes only and will not limit the scope of the invention in any way. In the present invention, to study the composition of organic fillers and analyse the quantity of the starch-containing sacs present in sample organic fillers from different areas, several tests were conducted according to the TAPPl T419 and TAPPl T21 1 standards. The test results are shown in Table 1 and Table 2.

Table 1 The composition of organic fillers samples

Table 2 The amount of fibrous portion of a sac shape containing starch in the organic fillers samples

In addition, an analysis of the proportion of organic filler particle size to be added to the sheet was conducted according to TAPPI T233 standard. The results are shown in Table 3. The average particle size of the sample organic fillers from different areas was also analyzed using the Particle Size Analyser. The results are shown in Table 4.

Table 3 The percentage of the average particle size of the organic filler samples

Source of organic The percentage of the average particle size of the organic filler fillers samples

Larger than 595 74-595 Smaller than 74 Micrometer Micrometer Micrometer

Area A 13.2 66.5 20.3

Area B 26.8 58.7 14.5

Area C 0.9 60.3 38.8

Area D 19.8 42.0 38.2 Table 4 The average particle size of the organic filler samples

The following example shows the mechanical properties of the sheet with the organic filler in various ratios.

Example 1 Ring Crush Test (RCT)

The Ring Crush Test (RCT) was conducted according to ISO 12192 standard by preparing sheets having the organic filler ratios of 5, 10, 15, 20, 30 % respectively, then comparing to the sheet without organic filler (0 %). The test results are shown in Table 5.

Table 5 Ring Crush Test results

Amount of organic filler Ring Crush resistance

(%) (Newton)

(%)

0 224 -

5 249 1 1.2

10 254 13.4

15 276 23.2

20 290 25.0

30 290 33.5 Example 2: Corrugated Medium Test (CMT)

The Corrugated Medium Test (CMT) was conducted according to ISO 7263 standard conducted by preparing sheets having the organic filler ratios of 5, 10, 15, 20, 30 % respectively, then comparing to the sheet without organic filler (0 %). The test results are shown in Table 6.

Table 6 Corrugated Medium Test results

Example 3 Short Span Compression Test (SCT)

The Short Span Compression Test (SCT) was conducted according to ISO 9895 standard by preparing sheets having the organic filler ratios of 5, 10, 15, 20, 30 % respectively, then comparing to the sheet without organic filler (0 %). The test results are shown in Table 7.

Table 7 Short Span Compression Test results

Amount of organic filler Short Span Compression Increase in Short Span

(%) resistance (N-m/g) Compression resistance (%)

0 16.3 -

5 17.9 9.8

10 18.5 13.5

15 19.4 19.0

20 20.0 22.7

30 21.1 29.5 Example 4 Brust Strength test

The Brust Strength test was conducted according to ISO 2759 standard by preparing sheets having the organic filler ratios of 5, 10, 15, 20, 30 % respectively, then comparing to the sheet without organic filler (0 %). The test results are shown in Table 8.

Table 8 Brust Strength Test results

Example 5 Folding Endurance test

The Folding Endurance test was conducted according to ISO 5626 standard by preparing sheets having the organic filler ratios of 5, 10, 15, 20, 30 % respectively, then comparing to the sheet without organic filler (0 %). The test results are shown in Table 9.

Table 9 Folding Endurance Test results

Amount of organic filler Folding Endurance (log Increase in Folding

(%) (10)) Endurance

(%)

0 1.34 -

5 1.58 17.9

10 1.65 23.1

15 1.86 38.8

20 2.13 58.9

30 2.17 61.9 Having an increased strength, the sheets with the organic filler of the present invention additives can reduce the amount of dry strength agent, which may be polymers or modified starch, to be added during the manufacturing process. It can also minimize the starch to be sprayed on the surface of the sheet to increase its strength as well. Several features and/or embodiments of the invention described above may be combined with other features and/or embodiments as appropriate. Although this invention is illustrated by specific embodiments, it is to be understood that the claimed invention is not limited by such embodiments. The persons skilled in the art will appreciate that various modifications can be made to the described invention without departing from the scope of the appended claims.

Claims

1. Sheet with organic filler comprising a fibrous portion and an organic filler wherein; the organic filler consists of solid component and moisture and; the solid component in the organic filler comprises a fibrous portion of a sac shape containing starch.

2. Sheet with organic filler according to claim 1 wherein the fibrous portion of a sac shape containing starch is present at least 15 %.

3. Sheet with organic filler according to claim 1 wherein which the organic filler has an average particle size in the range of 100-500 microns.

4. Sheet with organic filler according to claims 1 or 3 wherein the organic filler has an average particle size in the range of 250-450 microns.

5. Sheet with organic filler according to claim 1 wherein the solid component consists of starch at the proportion of 30-90 % by weight of the total weight of solid component.

6. Sheet with organic filler according to claims 1 or 5 wherein the solid component consists of starch at the proportion of 60-90 % by weight of the total weight of solid component.

7. Sheet with organic filler according to claim 1 having the organic filler at least 5 % by weight and having an increase in ring crush resistance according to ISO 12192 standard (Ring Crush Test, RCT) at least by 10 % compared with the sheet without such organic filler.

8. Sheet with organic filler according to claim 1 having the organic filler at least 3 % by weight and having an increase in corrugated medium crush resistance according to ISO 7263 standard (Corrugated Medium Test, CMT) at least by 10 % compared with the sheet without such organic filler.

9. Sheet with organic filler according to claim 1 having the organic filler at least 5 % by weight and having an increase in short span compression according to ISO 9895 standard (Short Span Compression Test, SCT) at least by 5 % compared with the sheet without such organic filler.

10. Sheet with organic filler according to claim 1 having the organic filler at least 5 % by weight and having an increase in burst strength according to ISO 2759 standard (Burst Strength Test) by at least 5 % compared with the sheet without such organic filler.

1 1. Sheet with organic filler according to claim 1 having the organic filler at least 5 % by weight and having an increase in the resistance to fracture folding according to ISO 5626 standard (Folding Endurance Test) by at least 10 % compared to sheet without such organic filler.

12. Sheet with organic filler according to any of claims 1-6 wherein the organic filler is prepared from agricultural materials.

13. Sheet with organic filler according to claim 12 wherein the agricultural materials may be selected from potato, sweet potato, tapioca, sago, taro and yam.

14. Sheet with organic filler according to any one of the preceded claims wherein the sheet may be selected from paper, natural polymeric materials, sheet consisting of fibers and sheet consisting predominantly of cellulosic fibers.