WO2015042874A1

WO2015042874A1 - Process and apparatus for forming rolled or folded brim on molded fiber pulp article

Info

Publication number: WO2015042874A1
Application number: PCT/CN2013/084462
Authority: WO
Inventors: Kam Yiu WONG
Original assignee: Sabert Asia Holdings Limited
Priority date: 2013-09-26
Filing date: 2013-09-27
Publication date: 2015-04-02

Abstract

The present invention relates to a process and apparatus for forming a rolled or folded brim on a molded fiber pulp article and articles formed by such processes and apparatuses. The process includes steps of pre-treating the molded fiber pulp article with chemical solvent to temporarily reduce rigidity of a brim portion of the molded fiber pulp article, and rolling or folding a brim on the molded fiber pulp article. The apparatus for forming a rolled or folded brim on a molded fiber pulp article includes a moving mechanism having a pretreating station for pre-treating the molded fiber pulp article with chemical solvent to temporarily reduce rigidity of a brim portion of the molded fiber pulp article and a forming mechanism for rolling or folding a brim on the molded fiber pulp article. The process and apparatus can improve the strength, and rigidity of the molded fiber pulp article and reduce the weight thereof compared to such articles with flat rims.

Description

PROCESS AND APPARATUS FOR FORMING ROLLED OR FOLDED BRIM ON

MOLDED FIBER PULP ARTICLE

FIELD OF THE INVENTION

[0001 ]The present invention generally relates to a process and an apparatus for forming a rolled or folded brim on a molded fiber pulp article.

BACKGROUND OF THE INVENTION

[0002] Molded fiber pulp articles are made from by-products of organic plants such as bagasse, bamboo, wheatgrass, etc. Due to the characteristics of these raw materials, the brim of conventional molded fiber pulp articles is always flat (as shown in FIG. 4). The gauge at the brim is close to or almost the same as the body of the article, and as a consequence, the flat brim cannot provide sufficient strength on fitting with the lid to achieve tight sealing. The flat brim may also create an uncomfortable feeling to users when they use the molded fiber pulp articles as drinkware. Accordingly, molded fiber pulp products are used primarily for support packaging applications at present.

[0003] In contrast, over the years, various types of paperboard containers or canisters have been manufactured with a rolled brim at the upper periphery thereof. Such rolled brims, or curved brims, serve both structural as well as aesthetic functions which are critical to the acceptance of the product by the consumer. Many patents have elaborated the details of the benefits and relevant manufacturing processes for forming rolled brims on paperboard containers and canisters.

[0004] For paperboard products, the conventional brim curl forming equipment applies a force on an un- finished annular edge inserted into a die which curls the brim outwardly, forming a roughly elliptical rim.

If the paperboard stock material is relatively heavy and/or the radius of curvature of the annular edge to be rolled is relatively small, it may not be possible to properly form a brim, as cracks may appear on the outer surface of the brim.

[0005] WO 97/05024 relates to a canister- type carton having a buckle-controlled brim curl, a method of forming such buckle-controlled brim curl, as well as a paperboard blank used to form such a carton. The container of WO 97/05024 is formed by providing a paperboard shell having an unfinished annular exposed edge; directing the unfinished annular edge into a forming surface of a forming die; and urging the unfinished annular edge into the forming die and controlling an initial buckling point of the unfinished annular edge of the paperboard shell such that a substantially defect-free prolate rolled toroidal brim is formed. In order to aid in the formation of the prolate rolled toroidal brim, a lubricant is provided on one of either the paperboard shell or a forming surface of the forming die, which allows the unfinished annular edge of the paperboard shell to travel further along the forming surface before buckling of the unfinished annular edge is initiated.

[0006] However, none of these manufacturing processes and benefits of the paperboard products are applicable to molded fiber pulp articles for many reasons.

[0007] Of course, as already mentioned above, the first reason is that the raw materials of the paperboard articles and the molded fiber pulp articles are quite different.

[0008] Furthermore, as is well known, a paperboard article is mainly made by the following processes:

(1) Folding and assembling separated paperboard sheets to form a product shape, in which case joint lines will appear on the product surface; or

(2) Using pressure to deform the paper cardboard to the required article shape, in which case the surface will have wrinkles. [0009] By contrast, molded fiber pulp articles are made by collecting pulp fibers and then forming the article shape inside a mold. Due to the mold processing method different from the paperboard article, the appearance of molded fiber pulp articles is not the same as paperboard articles. There are no joint lines on the article surface, because it is formed by an integrated molded fiber process.

[0010] The rigidity of a molded fiber pulp article is affected by the tensile and bending stiffness in both the vertical and circumferential directions of the article due to the particular raw materials and the mold forming process thereof. Thus, the manufacturing process of paperboard containers or canisters with rolled or folded brims cannot be directly applied to molded fiber pulp articles. No prior art can solve the above problem of molded fiber pulp articles.

[0011] So, there is a significant need to improve molded fiber pulp articles and provide a manufacturing process for forming improved molded fiber pulp articles.

SUMMARY OF THE INVENTION

[0012] The primary object of the present invention is to overcome the aforementioned shortcomings associated with the prior art molded fiber pulp articles.

[0013] Another object of the present invention is to provide a new process and apparatus for forming a rolled or folded brim on a molded fiber pulp article which can increase part strength at the brim.

[0014] Yet another object of the present invention is to provide a new process and apparatus for forming a rolled or folded brim on a molded fiber pulp article which can reduce part weight but maintain the same brim strength and thereby save materials and be cost effective. For example, the part weight may be re- duced by about 5% to about 50%.

[0015] A still further object of the present invention is to provide a new process and apparatus for forming a rolled or folded brim on a molded fiber pulp article which can significantly increase the rigidity of the molded fiber pulp article structure. For example, the rigidity of the molded fiber pulp article structure can be increased by about 50% to about 400%.

[0016] Yet another object of the present invention is to provide a new process and apparatus for forming a rolled or folded brim on a molded fiber pulp article which can significantly improve the sealing process when a lid is placed on the brim.

[0017] A still further object of the present invention is to provide a new process and apparatus for forming a rolled or folded brim on a molded fiber pulp article which has a wall thickness of about 0.3 mm to about 3.0 mm. Yet a further object of the present invention is to provide molded fiber pulp articles made in accordance with the processes and apparatuses disclosed herein.

[0018] The process of the embodiments of the present invention can be applied on all types of molded fiber pulp tableware, such as molded fiber pulp bowls, molded fiber pulp cups, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other features and advantages of the present invention will become apparent from the following more detailed description, take in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

[0020] FIG. 1 shows an apparatus for forming a rolled or folded brim on molded fiber pulp articles according to an embodiment of the present invention.

[0021] FIG. 2 shows a process for forming a rolled or folded brim on molded fiber pulp articles according to an embodiment of the present invention. [0022] FIG.3 is a cross-section view showing an exemplified molded fiber pulp article before brim rolling/folding.

[0023] FIG.4 is a cross-section view showing a molded fiber pulp article with flat brim.

[0024] FIG. 5 is a perspective view of one type of molded fiber pulp article with a rolled/folded brim formed by the process and apparatus of an embodiment of the present invention.

[0025] FIG. 6 is an enlarged cross-section view of a rolled brim according to an embodiment of the pre- sent invention.

[0026] FIG. 7 is an enlarged cross-section view of a folded brim according to an embodiment of the present invention.

[0027] FIG. 8 is a cross-section view of another exemplified molded fiber pulp article with a lid according to an embodiment of the present invention.

[0028 ]FIG. 9 is an enlarged partial view of FIG. 8 showing the molded fiber pulp article with the lid.

[0029] FIG. 10 is a schematic view showing equipment for measuring brim strength.

[0030] FIG. 11 shows another exemplified apparatus for forming a rolled or folded brim on molded fiber pulp articles according to another embodiment of the present invention.

DESCRIPTION OF THE EMBODIMENTS

[0031] The present invention provides a new process and apparatus for forming a rolled or folded brim on molded fiber pulp articles.

[0032] The fiber pulp material includes, for example, bagasse, bamboo, wheatgrass and other natural or- ganic materials which have fibers suitable for producing molded pulp articles. The rigidity of a molded fiber pulp article is affected by the tensile and bending stiffness in both the vertical and circumferential directions of the article. According to embodiments of the present invention, mixing fiber pulp materials may be used to achieve the better performance of brim forming. The composition, based on the total weight of the composition, comprises:

Bagasse, 0% - 100%

Bamboo, 0% - 100%

Wheat Straw, 0% - 50%

Reed, 0% - 50%

The lignin of mixing fiber pulp material may be in a percentage range of about 0.5% to about 25% (also based on the total weight of the composition). The test method to measure the percentage of lignin is to follow GB / T747-2003 or GB / T10337-2008.

[0033] Moreover, there is no limitation to the additives used in the molded fiber pulp articles. Examples of additives include, but are not limited to, water and oil resistance additives, are Kymene 852, ASAHI AG-E860, CLARIANT Cartafluor CFI, Dupont Foraperle 321, Hercules Hereon 25, Scokff Resisnex EK-318, SICONG F-913 Hercules Herconl95 and the like.

[0034] According to embodiments of the present invention, the molded fiber pulp articles may have plastic laminated film on the inner surface (such as a food-contact layer) and /or the outer surface (such as a non-food layer) of the article. The material of the film can be, for example, Polyethylene, Polypropylene, Polyester, Polylactic Acid or any thermoplastics, bio-degradable materials and other similar plastic materials which are suitable for making films. The gauge of the laminated film may range from about 0.03 mm to about 0.50 mm. [0035] Furthermore, according to some embodiments of the present invention, the raw material of the molded fiber pulp can be a natural color, a bleached white color or any other color achieved by a dying or treatment process.

[0036] FIG. 1 shows an embodiment of the apparatus for forming a rolled or folded brim on molded fiber pulp articles according to an embodiment of the present invention. As shown in FIG. 1 , the apparatus 1 comprises a forming mechanism 10 and a moving mechanism 20 cooperating with the forming mechanism 10. The forming mechanism 10 comprises at least one die device for forming a rolled or folded brim. In the example shown in FIG. 1, there are two die devices 101 and 102. Each of the die devices of the forming mechanism 10 has an upper profile die and a lower profile die and a heating system. The upper profile die and the lower profile die move towards/away from each other to process the molded fiber pulp articles. The moving mechanism 20 rotates about an axis I and comprises at least one platform for receiving the part (i.e., the molded fiber pulp article) arranged around the axis I in a circular manner. In the exemplified embodiment shown in FIG. 1, there are eight platforms 200 around the axis I. Like a carousel, when the moving mechanism 20 rotates, the platforms move. Those skilled in the art can conceive that the moving mechanism may not rotate like a carousel, but instead move linearly like a conveying belt as shown in FIG. 11, and the moving mechanism 20' shown in FIG. 11 can perform the same function as the moving mechanism 20. Those skilled in the art can conceive still other modifications of the moving mechanism.

[0037]The moving mechanism 20 has different working stations. As the moving mechanism 20 rotates around the central axis I, the platforms 200 with the parts (i.e., the molded fiber pulp article) are moved into specific working stations. As shown in the embodiment of FIG. 1, there are: a part loading station 21, a brim preforming station 27, a pretreating station 22, a first step brim forming station 23, a second step brim forming station 24, a part idle station 25 and, a part unloading station 26. In a variation of the embodiment of FIG. 1 , the brim preforming station 27 may be omitted. The moving mechanism 20 also comprises spraying means for spraying chemical solvent or steam arranged at the pretreating station.

[0038] Likewise, the moving mechanism 20' in FIG. 11 also has different working stations 21 '-27'. And when the moving mechanism 20' moves, the platforms move along the axis Γ and pass through the part loading station 21 ' , brim preforming station 27' , pretreating station 22' , first step brim forming station 23' , second step brim forming station 24', part idle station 25' and part unloading station 26' in turn. Here too, in one variation, the brim preforming station 27 may be omitted.

[0039]FIG. 2 shows the process for forming a rolled or folded brim on molded fiber pulp articles. The steps shown in the dotted line boxes are optional. For example, when a molded fiber pulp article before brim rolling/folding is already in a required state, the steps 2001 and 2004 shown in FIG. 2 may be omitted.

[0040]FIG. 3 is a cross-section view showing a molded fiber pulp article before brim rolling/folding according to an embodiment of the present invention. The molded fiber pulp article 300 has a body 301 with a preformed slanted periphery 302. The slanted periphery 302 has a length El, preferably ranging from about 3 mm to about 10 mm. The preferable length of El is about 7 mm. The angle of the slanted periphery 302 with respect to the wall of the body 301 is Al, preferably ranging from about 5° to about 40°. If the angle Al is less than about 12.5°, the molded fiber pulp article may be formed with a rolled or folded brim with a first brim forming step (step 2003 as shown in FIG. 2) and there is no need for step 2004 shown in FIG. 2. If the angle Al is greater than about 12.5°, then the second forming step is preferably performed. The preferred angle Al is less than about 25°.

[0041] According to the process of an embodiment of the present invention, firstly, the molded fiber pulp article is loaded on one of the platforms at the part loading station 21, 21 ' (step 2000 as shown in FIG. 2). If the molded fiber pulp article does not have a slanted periphery having a length El ranging from about 3 mm to about 10 mm and an angle Al ranging from about 5° to about 25°, the molded fiber pulp article will be preformed at the preforming station 27, 27' of the moving mechanism 20, 20' (step 2001). Oth- erwise, the moving mechanism 20, 20' rotates clockwise/moves forward and the platform is moved into the pretreating station 22, 22' (step 2002). [0042] In the pre-treating station 22, 22', the spraying means sprays chemicals and/or pressurized steam onto the molded fiber pulp article and the article undergoes pretreatment with chemical solvent and/or steam to temporarily reduce the rigidity of the brim portion of the molded fiber pulp article. By "tempo- rarily", it is meant that the rigidity of the brim portion is reduced for a period of time after the pretreatment which lasts until the chemical solvent and/or pressurized steam has substantially evaporated, which may be, for example, a period of time in a range of about 0.2 sec to 20 sec. The chemical solvent is quickly evaporating, food grade substance such as, for examples, water, silicon oil, corn oil, mineral water and the like. If pressurized steam is used, the steam may be in a temperature range of about 95 ^°C to about 110^°C and a pressure of about 1 bar to about 8 bars.

[0043] After step 2002, the moving mechanism 20, 20' further rotates/moves and the platform is moved into the first step brim forming station 23, 23' (step 2003). In this station, the molded fiber pulp article undergoes a first brim forming. The lower profile die is first moved upwardly around the upper end of the molded fiber pulp article to the top edge where it firmly holds the article top and the upper profile die is then moved downwardly to form the rolled/folded shape. Meanwhile, the heating system of the die device may be operable in a temperature range of about 50°C to about 200°C and may be applied for a time period ranging from about 0.2 sec to about 20 sec, for speeding up the evaporation process. The steam or chemical solvent used in embodiments of the present invention can help to minimize fiber clips peeling off and eliminate crack lines during the rolled/ folded brim formation step. Afterward, both upper and lower profile dies descend downwardly towards to the stationary platform for completing one cycle, whereupon the platform may be rotated to a second step brim formation station 24, 24' if the slanted periphery has an angle Al ranging from about 12.5° to about 25° (step 2004).

[0044] Next, the moving mechanism 20, 20' rotates/moves again and the platform is moved into the part idle station 25, 25' where the molded fiber pulp article is kept on the platform for a while, e.g. a time period ranging from about 0.2 second to about 10 seconds (step 2005), to accommodate drying. After that, the moving mechanism 20, 20' rotates/moves and the platform is moved into the part unloading station 26, 26' where the finished molded fiber pulp article is unloaded from the platform (step 2006).

[0045] According to some embodiments of the present invention, the rolled and folded brim process can be applied to any type of tableware made by a molded fiber pulp process.

[0046] FIG.4 is a cross-section view showing a molded fiber soup bowl with a flat brim. The flat brim cannot provide sufficient strength for fitting with a lid to provide tight sealing. The flat brim will also create an uncomfortable feeling to users when they use the molded fiber pulp articles as drinkware. FIGS. 5-9 show different molded fiber soup bowls with rolled or folded brims formed by the process and apparatus of embodiments of the present invention.

[0047] FIG. 5 is a molded fiber soup bowl without a lid. The bowl may be formed with a rolled brim as shown in FIG. 6 or a folded brim as shown in FIG. 7 by using the process and the apparatus of embodiments of the present invention. As shown in FIG. 6, the bowl has a rolled brim with radius Rl. The radius Rl ranges from about 1.0 mm to about 15 mm. The brim strength ranges from about 1.0N to about 20N. As shown in FIG.7, the bowl has a wall thickness Tl ranging from about 0.3 mm to about 3.0 mm and a folded brim with a gap Dl ranging from about 0.5 mm to about 3 mm.

[0048] FIG.8 depicts a molded fiber soup bowl with a lid. The fitting can provide an audible "pop" sound due to the rolled brim fitting into the inner undercut of the lid (see FIG. 9). The lid material can be molded fiber pulp, PLA, thermoplastic, or other environmental plastic materials which are suitable for injection molding and thermoforming processes.

[0049] There is no limitation in applying embodiments of the present invention to molded fiber pulp articles with brims of different shapes. [0050] The molded fiber pulp articles with rolled or folded brims formed by the processes disclosed herein can dramatically improve the strength and rigidity thereof. FIG.10 is a schematic view showing equipment 400 for measuring brim strength. The equipment 400 comprises a force plate 401 and a supporting platform 402 having a V-shaped surface 403. The force plate 401 is positioned above the V- shaped surface 403.

[0051] The test method is as follows:

(1) Place the molded fiber pulp article into the center position of the V-shaped surface 403 of the equipment 400 shown in FIG. 10;

(2) Make sure that the brim of the molded fiber pulp article is in contact with the surface of force plate 401 ;

(3) Adjust the position of force meter and reset the value to zero;

(4) Gradually apply force on the force plate 401 ;

(5) Stop applying force when the brim deformation is 5mm;

(6) Record the displayed value of the force meter.

[0052] The following two Examples 1 and 2 compare the molded fiber pulp articles with a flat brim with a rolled brim formed by the process and apparatus of embodiments of the present invention.

[0053] Example 1 :

[0054] Fiber pulp articles are molded by natural bagasse pulp with the dimensions 061.1mm x 70.4mm. Some of the molded fiber pulp articles are formed with rolled brims by the process and apparatus of embodiments of the present invention and some of them are not further processed and only have flat brims. Ten samples are selected randomly from the molded fiber pulp articles with the rolled brims and ten samples are selected randomly from the articles with flat brims. The twenty samples are tested by the equipment 400 shown in FIG. 10. Table 1 shows the brim strength and part (i.e., the molded fiber pulp article) weight comparison between the flat brim articles and the rolled brim articles.

[0055]Table 1 : Brim strength (in Newtons) and part weight comparison between flat brim and rolled brim

Flat Brim Rolled Brim

Sample No. Part Part

Brim Brim

Weight Weight

Strength (N) Strength (N)

(gram) (gram)

1 3.4 1.3 3.4 3.5

2 3.5 1.4 3.5 3.6

3 3.4 1.3 3.5 3.6

4 3.4 1.3 3.4 3.5

5 3.4 1.4 3.4 3.5

6 3.5 1.5 3.4 3.5

7 3.5 1.5 3.4 3.6

8 3.4 1.3 3.4 3.5

9 3.4 1.4 3.5 3.6

10 3.5 1.5 3.5 3.6

Min. 3.4 1.3 3.4 3.5

Max. 3.5 1.5 3.5 3.6

Average 3.44 1.39 3.44 3.55 Dimensions of molded fiber pulp 061.1mm x 70.4mm

Average wall thickness 0.306mm

Density 0.69 g/cm³

Material 100% Natural bagasse

[0056] As shown in Table 1, the average part weight of the ten samples with flat brims is 3.44 gram, and the average weight of the ten samples with rolled brims is also 3.44 gram. In contrast, with the same average weight, the average brim strength of the ten samples with flat brims is 1.39 N yet the average brim strength of the ten samples with rolled brims formed by the process and apparatus of the present inven- tion is 3.55 N, which is dramatically improved, i.e., the strength of the molded fiber pulp articles with rolled brims is about 255% higher than that of the similar molded fiber pulp articles with flat brims.

[0057] Example 2: [0058] Fiber pulp articles are molded by natural bagasse pulp with the dimensions 061.1mm x 70.4mm. Some of the molded fiber pulp articles are formed with rolled brims by the process and apparatus of embodiments of the present invention and some of them only have flat brims. In order to see the results clearly, brim strength is selected as a base reference. Ten samples are selected randomly from the molded fiber pulp articles with rolled brims and ten samples are selected randomly from the articles with flat brims. The twenty samples are tested by the equipment 400 shown in FIG. 10. Table 2 shows the brim strength and part (i.e., the molded fiber pulp article) weight comparison between the flat brim articles and the rolled brim articles.

[0059]Table 2: Brim strength and part weight comparison between flat brim and rolled brim

Dimensions of molded fiber pulp 061.1mm x 70.4mm

Average wall thickness of flat brim molded fiber pulp 0.460mm

Average wall thickness of rolled brim molded fiber pulp 0.334mm

Density 0.69 g/cm³

Material 100% Natural bagasse pulp [0060] As shown in Table 2, the average brim strength of the ten samples with flat brims is 4.14 N, and the average brim strength of the ten samples with rolled brims is 4.16 N, which is almost the same. In contrast, with almost the same brim strength, the average part weight of the ten samples with flat brims is 5.16 gram yet the average part weight of the ten samples with rolled brims formed by the process and apparatus of embodiments of the present invention is 3.76 gram, which is dramatically reduced. In view of the measured result, if the strength (tolerance is ± 0.1N) of the molded fiber pulp articles with flat and rolled brims is kept the same, the part weight of the rolled brim molded fiber pulp product is about 27% lighter than the flat brim molded fiber pulp product. In other words, the process and apparatus of the present invention can save material and reduce cost. [006 l]The invention has been described in detail with reference to the preferred embodiments thereof. However, it will be appreciated that those skilled in the art, upon consideration of the disclosure in this description and drawings, may make modifications and improvements within the spirit and scope of the present invention. Accordingly, the above-described embodiments should be understood as illustrative, and not limiting. The scope of the invention being defined by the following claims.

Claims

WHAT IS CLAIMED IS:

1. A process for forming a rolled or folded brim on a molded fiber pulp article, comprising steps of: pre-treating the molded fiber pulp article with chemical solvent to temporarily reduce rigidity of a brim portion of the molded fiber pulp article;

rolling or folding a brim on the molded fiber pulp article.

2. The process for forming a rolled or folded brim on a molded fiber pulp article according to claim 1 , wherein pre-treating the molded fiber pulp article with chemical solvent further comprises heating an upper profile die and a lower profile die with a heating system to speed up evaporation of the chemical solvent.

3. The process for forming a rolled or folded brim on a molded fiber pulp article according to claim 1 , further comprising a step of pre-forming a slanted periphery on the brim portion of the molded fiber pulp article before pre-treating the molded fiber pulp article with chemical solvent.

4. The process for forming a rolled or folded brim on a molded fiber pulp article according to claim 1 or 2, wherein rolling or folding a brim on the molded fiber pulp article comprises moving upwardly a lower profile die around an upper end of the molded fiber pulp article to hold a top of the molded fiber pulp article.

5. The process for forming a rolled or folded brim on a molded fiber pulp article according to claim 4, wherein rolling or folding a brim on the molded fiber pulp article comprises moving downwardly an upper die to form a rolled or folded shape of the molded fiber pulp article.

6. The process for forming a rolled or folded brim on a molded fiber pulp article according to claim 1 , comprising the step of forming the molded fiber pulp article inside a mold with the material selected from the following group of: bagasse, bamboo, wheat straw, reed and the combination thereof.

7. The process for forming a rolled or folded brim on a molded fiber pulp article according to claim 6, wherein the step of forming the molded fiber pulp article inside a mold includes adding lignin in a percentage range of about 0.5% to about 25% based on the total weight of the composition.

8. The process for forming a rolled or folded brim on a molded fiber pulp article according to claim

6 or 7, wherein the step of forming the molded fiber pulp article inside a mold includes adding additives selected from the following group of: Kymene 852, ASAHI AG-E860, CLARIANT Cartafluor CFI, Du- pont Foraperle 321, Hercules Hereon 25, Scokff Resisnex EK-318, SICONG F-913 Hercules Herconl95.

9. The process for forming a rolled or folded brim on a molded fiber pulp article according to claim

6 or 7, before pre-treating the molded fiber pulp article, the process further comprising a step of laminating on an inner surface and/or an outer surface of the molded fiber pulp article a film made of the material selected from the following group of: Polyethylene, Polypropylene, Polyester, Polylactic Acid or thermoplastics, bio-degradable materials.

10. An apparatus for forming a rolled or folded brim on a molded fiber pulp article, comprising: a moving mechanism having a pretreating station for pre-treating the molded fiber pulp article with chemical solvent to temporarily reduce rigidity of a brim portion of the molded fiber pulp article;

a forming mechanism for rolling or folding a brim on the molded fiber pulp article.

11. The apparatus for forming a rolled or folded brim on a molded fiber pulp article according to claim 10, wherein the moving mechanism comprises spraying means for spraying chemical solvent arranged at the pretreating station.

12. The apparatus for forming a rolled or folded brim on a molded fiber pulp article according to claim 10 or 11, wherein the moving mechanism comprises a preforming station for forming a slanted periphery on the brim portion of the molded fiber pulp article before it undergoes pretreating.

13. The apparatus for forming a rolled or folded brim on a molded fiber pulp article according to claim 10 or 11, wherein the forming mechanism comprises at least one die device for forming a rolled or folded brim.

14. The apparatus for forming a rolled or folded brim on a molded fiber pulp article according to claim 13, wherein each die device comprises an upper profile die, a lower profile die and a heating system for speeding up evaporation of the chemical solvent.