3-D formable sheet material

Abstract

The present invention relates to a 3D-formable sheet material, a process for the preparation of a 3D-formed article, the use of a cellulose material and at least one particulate inorganic filler material for the preparation of a 3D-formable sheet material and for increasing the stretchability of a 3D-formable sheet material, the use of a 3D-formable sheet material in 3D-forming processes as well as a 3D-formed article comprising the 3D-formable sheet material according.

Claims

1. A 3D-formable sheet material comprising a) a cellulose material in an amount from 5 to 55 wt.-%, based on the total dry weight of the 3D-formable sheet material, wherein the cellulose material is a cellulose material mixture comprising i) nanofibrillated cellulose and/or microfibrillated cellulose in an amount of ≥55 wt.-%, based on the total dry weight of the cellulose material mixture, and, wherein the nanofibrillated cellulose and/or microfibrillated cellulose has been obtained by nanofibrillating and/or microfibrillating a cellulose fibre suspension in the absence or presence of fillers and/or pigments, wherein the cellulose fibres of the cellulose fibre suspension are recycled or virgin fibre material; ii) cellulose fibres in an amount of ≤45 wt.-%, based on the total dry weight of the cellulose material mixture, and the sum of the amount of the nanofibrillated cellulose and/or microfibrillated cellulose and the cellulose fibres is 100 wt.-%, based on the total dry weight of the cellulose material mixture, wherein the cellulose fibres are obtained from recycled fibre material; and b) at least one particulate inorganic filler material in an amount of ≥45 wt.-%, based on the total dry weight of the 3D-formable sheet material, wherein the sum of the amount of the cellulose material and the at least one particulate inorganic filler material is 100 wt.-%, based on the total dry weight of the cellulose material and the at least one particulate inorganic filler material.

2. The 3D-formable sheet material according to claim 1, wherein the 3D-formable sheet material comprises a) the cellulose material in an amount from 15 to 55 wt.-%, based on the total dry weight of the 3D-formable sheet material; and b) the at least one particulate inorganic filler material in an amount from 45 to 85 wt.-%, based on the total dry weight of the 3D-formable sheet material.

3. The 3D-formable sheet material according to claim 1, wherein the 3D-formable sheet material has a) a normalized stretch increase per level of moisture content in the range from 0.15 to 0.7% per percent moisture, and/or b) an elongation at break of at least 6%, and/or c) a sheet weight from 50 to 500 g/m2.

4. The 3D-formable sheet material according to claim 1, wherein the 3D-formable sheet material has a) a normalized stretch increase per level of moisture content in the range from 0.15 to 0.7% per percent moisture, and/or b) an elongation at break of at least 6%, and/or c) a sheet weight from 80 to 300 g/m2.

5. The 3D-formable sheet material according to claim 1, wherein the 3D-formable sheet material has a) a normalized stretch increase per level of moisture content in the range from 0.15 to 0.7% per percent moisture, and/or b) an elongation at break of at least 6%, and/or c) a sheet weight from 80 to 250 g/m2.

6. The 3D-formable sheet material according to claim 1, wherein the at least one particulate inorganic filler material is a particulate natural, synthetic or blended inorganic material.

7. The 3D-formable sheet material according to claim 1, wherein the at least one particulate inorganic filler material is selected from the group consisting of: an alkaline earth metal carbonate, metal sulfate, metal silicate, metal oxide, kaolin, calcined kaolin, talc, mica or any mixture or combination thereof.

8. The 3D-formable sheet material according to claim 1, wherein the at least one particulate inorganic filler material is selected from the group consisting of: barite, gypsum, titania or iron oxide).

9. The 3D-formable sheet material according to claim 1, wherein the at least one particulate inorganic filler material is at least one particulate calcium carbonate containing material.

10. The 3D-formable sheet material according to claim 9, wherein the at least one particulate calcium carbonate-containing material is precipitated calcium carbonate.

11. The 3D-formable sheet material according to claim 10, wherein the precipitated calcium carbonate is selected from one or more of the group consisting of aragonitic, vateritic and calcitic mineralogical crystal forms.

12. The 3D-formable sheet material according to claim 9, wherein least one particulate calcium carbonate-containing material is dolomite.

13. The 3D-formable sheet material according to claim 9, wherein the at least one particulate calcium carbonate-containing material is at least one ground calcium carbonate material.

14. The 3D-formable sheet material according to claim 13, wherein the at least one ground calcium carbonate-containing material is selected from the group consisting of marble, chalk, limestone and mixtures thereof.

15. The 3D-formable sheet material according to claim 1, wherein the at least one particulate inorganic particulate inorganic material comprises both precipitated and ground calcium carbonate materials.

16. The 3D-formable sheet material according to claim 1, wherein the at least one particulate inorganic filler material has a) a weight median particle size d.sub.50 from 0.1 to 20 μm, and/or b) a specific surface area of from 0.5 to 200.0 m.sup.2/g as measured by the BET nitrogen method.

17. A process for the preparation of a 3D-formed article, the process comprising the steps of a) providing the 3D-formable sheet material according to claim 1, and b) forming the 3D-formable sheet material into a 3D-formed article, by a method selected from the group consisting of thermoforming, vacuum forming, air-pressure forming, deep-drawing forming, hydroforming, spherical forming, press forming and vacuum/air-pressure forming, hydroforming, spherical forming, press forming and vacuum/air-pressure forming.

18. The process according to claim 17, wherein the 3D-formable sheet material has been obtained by i) providing a cellulose material according to claim 1, ii) forming a presheet consisting of the cellulose material of step i), and iii) drying the presheet of step ii) into a 3D-formable sheet material.

19. The process according to claim 18, wherein the cellulose material of step i) is combined with at least one particulate inorganic filler material, wherein the at least one particulate inorganic filler material is at least one particulate calcium carbonate containing material.

20. The process according to claim 19, wherein the at least one particulate calcium carbonate-containing material is precipitated calcium carbonate.

21. The process according to claim 20, wherein the precipitated calcium carbonate is selected from one or more of the group consisting of aragonitic, vateritic and calcitic mineralogical crystal forms.

22. The process according to claim 19, wherein the at least one particulate inorganic filler material is dolomite.

23. The process according to claim 19, wherein the at least one particulate inorganic particulate inorganic material is at least one ground calcium carbonate material.

24. The process according to claim 23, wherein the at least one ground calcium carbonate-containing material is selected from the group consisting of marble, chalk, limestone and mixtures thereof.

25. The process according to claim 19, wherein the at least one particulate inorganic particulate inorganic material comprises both precipitated and ground calcium carbonate materials.

26. The process according to claim 18, wherein the cellulose material of step i) is combined with at least one particulate inorganic filler material, wherein the at least one particulate inorganic filler material has a) a weight median particle size d.sub.50 from 0.1 to 20 μm, and/or b) a specific surface area of from 0.5 to 200 m.sup.2/g, as measured by the BET nitrogen method.

27. The process according to claim 18, wherein i) the cellulose material is provided in a form of an aqueous suspension comprising the cellulose material in a range from 0.2 to 35 wt.-%, and/or ii) the at least one particulate inorganic filler material is provided in powder form, or in form of an aqueous suspension comprising the particulate inorganic filler material in an amount from 1 to 80 wt. %, based on the total weight of the aqueous suspension.

28. The process according to claim 18, wherein the cellulose material is a cellulose material mixture comprising nanofibrillated cellulose and/or microfibrillated cellulose that has been obtained by nanofibrillating and/or microfibrillating a cellulose fibre suspension in the absence of fillers and/or pigments, wherein the nanofibrillated cellulose and/or microfibrillated cellulose is in form of an aqueous suspension having a Brookfield viscosity in the range from 1 to 2,000 mPa.Math.s at 25° C., at a nanofibrillated cellulose and/or microfibrillated cellulose content of 1 wt. %, based on the total weight of the aqueous suspension.

29. The process according to claim 18, wherein the cellulose material is a cellulose material mixture comprising nanofibrillated cellulose and/or microfibrillated cellulose that has been obtained by nanofibrillating and/or microfibrillating a cellulose fibre suspension in the presence of fillers and/or pigments, wherein the nanofibrillated cellulose and/or microfibrillated cellulose is in form of an aqueous suspension having a Brookfield viscosity in the range from 1 to 2,000 mPa.Math.s at 25° C., at a nanofibrillated cellulose and/or microfibrillated cellulose content of 1 wt. %, based on the total weight of the aqueous suspension.

30. The process according to claim 18, wherein the process further comprises a step iv) of moisturizing the 3D-formable sheet material provided in step i) to a moisture content of 2 to 30 wt.-%, based on the total dry weight of the 3D-formable sheet material, before and/or during process step ii).

31. The process according to claim 17, wherein the 3D-formed article is selected from the group consisting of a packaging container, food container, blister pack, and food tray.

32. The process according to claim 18, wherein the cellulose material is a cellulose material mixture comprising nanofibrillated cellulose and/or microfibrillated cellulose that has been obtained by nanofibrillating and/or microfibrillating a cellulose fibre suspension in the absence of fillers and/or pigments, wherein the nanofibrillated cellulose and/or microfibrillated cellulose is in form of an aqueous suspension having a Brookfield viscosity in the range from 10 to 1,200 mPa.Math.s at 25° C., at a nanofibrillated cellulose and/or microfibrillated cellulose content of 1 wt. %, based on the total weight of the aqueous suspension.

33. The process according to claim 18, wherein the cellulose material is a cellulose material mixture comprising nanofibrillated cellulose and/or microfibrillated cellulose that has been obtained by nanofibrillating and/or microfibrillating a cellulose fibre suspension in the absence of fillers and/or pigments, wherein the nanofibrillated cellulose and/or microfibrillated cellulose is in form of an aqueous suspension having a Brookfield viscosity in the range from 100 to 600 mPa.Math.s at 25° C., at a nanofibrillated cellulose and/or microfibrillated cellulose content of 1 wt. %, based on the total weight of the aqueous suspension.

34. The process according to claim 18, wherein the cellulose material is a cellulose material mixture comprising nanofibrillated cellulose and/or microfibrillated cellulose that has been obtained by nanofibrillating and/or microfibrillating a cellulose fibre suspension in the absence of fillers and/or pigments, wherein the nanofibrillated cellulose and/or microfibrillated cellulose is in form of an aqueous suspension having a Brookfield viscosity in the range from 700 to 1000 mPa.Math.s at 25° C., at a nanofibrillated cellulose and/or microfibrillated cellulose content of 1 wt. %, based on the total weight of the aqueous suspension.

35. The process according to claim 18, wherein the cellulose material is a cellulose material mixture comprising nanofibrillated cellulose and/or microfibrillated cellulose that has been obtained by nanofibrillating and/or microfibrillating a cellulose fibre suspension in the presence of fillers and/or pigments, wherein the nanofibrillated cellulose and/or microfibrillated cellulose is in form of an aqueous suspension having a Brookfield viscosity in the range from 1 to 2 000 mPa.Math.s at 25° C., at a nanofibrillated cellulose and/or microfibrillated cellulose content of 1 wt. %, based on the total weight of the aqueous suspension.

36. The process according to claim 18, wherein the cellulose material is a cellulose material mixture comprising nanofibrillated cellulose and/or microfibrillated cellulose that has been obtained by nanofibrillating and/or microfibrillating a cellulose fibre suspension in the presence of fillers and/or pigments, wherein the nanofibrillated cellulose and/or microfibrillated cellulose is in form of an aqueous suspension having a Brookfield viscosity in the range from 100 to 600 mPa.Math.s at 25° C., at a nanofibrillated cellulose and/or microfibrillated cellulose content of 1 wt. %, based on the total weight of the aqueous suspension.

37. The process according to claim 18, wherein the cellulose material is a cellulose material mixture comprising nanofibrillated cellulose and/or microfibrillated cellulose that has been obtained by nanofibrillating and/or microfibrillating a cellulose fibre suspension in the presence of fillers and/or pigments, wherein the nanofibrillated cellulose and/or microfibrillated cellulose is in form of an aqueous suspension having a Brookfield viscosity in the range from 700 to 1000 mPa.Math.s at 25° C., at a nanofibrillated cellulose and/or microfibrillated cellulose content of 1 wt. %, based on the total weight of the aqueous suspension.

38. The process according to claim 19, wherein the at least one particulate inorganic filler material is a particulate natural, synthetic or blended inorganic material.

39. The process according to claim 19, wherein the at least one particulate inorganic filler material is selected from the group consisting of: an alkaline earth metal carbonate, metal sulfate, metal silicate, metal oxide, kaolin, calcined kaolin, talc, mica or any mixture or combination thereof.

40. The process according to claim 19, wherein the at least one particulate inorganic filler material is selected from the group consisting of: barite, gypsum, titania or iron oxide).

41. A 3D-formed packaging container, food container, blister pack, or food tray, comprising the 3D-formable sheet material according to claim 1.

42. A 3D-formed packaging container, food container, blister pack, or food tray, comprising the 3D-formable sheet material according to claim 6.

43. A 3D-formed packaging container, food container, blister pack, or food tray, comprising the 3D-formable sheet material according to claim 7.

44. A 3D-formed packaging container, food container, blister pack, or food tray, comprising the 3D-formable sheet material according to claim 10.

45. A 3D-formed packaging container, food container, blister pack, or food tray, comprising the 3D-formable sheet material according to claim 13.

46. A 3D-formed packaging container, food container, blister pack, or food tray, comprising the 3D-formable sheet material according to claim 15.

Description

DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows microfibrillated cellulose prepared in the presence of GCC particles.

(2) FIG. 2 shows microfibrillated cellulose prepared in the absence of filler and/or pigments.

(3) FIG. 3 refers to a diagram showing the relationship of stretch and moisture.

(4) The following examples may additionally illustrate the invention but are not meant to restrict the invention to the exemplified embodiments. The examples below show the 3D-formable sheet material and its excellent good mechanical properties such as stretchability and elongation at break according to the present invention:

EXAMPLES

(5) Measurement Methods

(6) The following measurement methods are used to evaluate the parameters given in the examples and claims.

(7) Solids Content of Aqueous Suspensions Like Pigment Slurries Cellulose Containing Samples

(8) The suspension solids content (also known as “dry weight”) was determined using a Moisture Analyzer MJ33 from the company Mettler-Toledo, Switzerland, with the following settings: drying temperature of 160° C., automatic switch off if the mass does not change more than 1 mg over a period of 30 s, standard drying of 5 to 20 g of suspension.

(9) Moisture Content
Moisture content(wt. %)=100(wt. %)−solids content(wt. %)

(10) Particle Size of Mineral Particles

(11) The weight median particle size d.sub.50 as used herein, as well as the top cut d.sub.98 is determined based on measurements made by using a Sedigraph™ 5120 instrument of Micromeritics Instrument Corporation. The method and the instruments are known to the skilled person and are commonly used to determine grain size of fillers and pigments. The measurement was carried out in an aqueous solution comprising 0.1 wt.-% Na.sub.4P.sub.2O.sub.7. The samples were dispersed using a high speed stirrer and supersonics. For the measurement of dispersed samples, no further dispersing agents were added.

(12) Fiber Length Measurement

(13) A length weighted average fiber length was determined with a Kajaani FS 200 (Kajaani Electronics Ltd, now Valmet, Finland). The method and the instrument are known to the skilled person and are commonly used to determine fiber morphology parameters. The measurement was carried out solids content of ca. 0.010 wt.-%.

(14) Freeness Tester (Schopper Riegler)

(15) The Schopper-Riegler degree (°SR) was measured according to the Zellcheming Merkblatt V/7/61 and standardized in ISO 5267/1.

(16) Brookfield Viscosity

(17) The Brookfield viscosity of the aqueous suspensions was measured one hour after the production and after one minute of stirring at 25° C.±1° C. at 100 rpm by the use of a Brookfield viscometer type RVT equipped with an appropriate disc spindle, for example spindle 1 to 6.

(18) Light Microscopy to Distinguish Between MFC Types

(19) Micrographs were taken with a light microscope using transmitted light and bright field method.

(20) Film Forming Device: “Scandinavian Type” Laboratory Sheets

(21) An apparatus as described in SCAN-CM64:00 “Preparation of laboratory sheets for physical testing” was used, some modifications (J. Rantanen et al., “Forming and dewatering of a microfibrillated cellulose composite paper”, BioResources 10(2), 2015, pages 3492-3506) were carried out.

(22) Film Forming Device: “Rapid Köthen Type” Laboratory Sheets

(23) An apparatus as described in ISO 5269/2 “Preparation of laboratory sheets for physical testing—Part 2: Rapid Köthen method” was used, some modifications were applied, see the methods section “MFC filler composite films produced with “Rapid Köthen Type” laboratory sheet former” for more details.

(24) Tensile Tester

(25) A L&W Tensile Strength Tester (Lorentzen & Wettre, Sweden) was used for determination of the elongation at break according to procedures described in ISO 1924-2.

(26) 3D Forming Equipment and Procedure

(27) A Laboratory Platen Press Type P 300 (Dr. Collins, Germany) was used for forming. Pressure, temperature, and pressing time were adjusted accordingly.

(28) Two aluminum dies were used. A first form with outer dimensions of 16 cm×16 cm×2.5 cm and a female die part representing a circular segment with a diameter of 10 cm and a depth of 1 cm representing linear stretch levels of ca. 3%. A second form with outer dimensions of 16 cm×16 cm×3.5 cm and a female die part representing a circular segment with a diameter of 10 cm and a depth of 2 cm, representing linear stretch levels of ca. 10%.

(29) Flexible rubber plates with the dimensions 20 cm×20 cm×1 cm made of EPDM (ethylene propylene diene monomer rubber)

(30) 1. Material

(31) Compound of Microfibrillated Cellulose (MFC) and Filler

(32) A compound of microfibrillated cellulose (MFC) and filler was obtained by treatment of 40 wt. % enzymatically (Buckman Maximyze 2535) and mechanically (disk refiner, to a freeness of >60° SR) pre-treated dissolving pulp together with 60 wt. % GCC filler (Hydrocarb® 60) at a solids content of 55% in a co-rotating twin screw extruder. The quality of the micro fibrillation is characterized with the microscopic image in FIG. 1.

(33) Microfibrillated Cellulose (MFC) without Filler

(34) A microfibrillated cellulose (MFC) as characterized with the microscopic image in FIG. 2 was used. It was available as a suspension with 3.8 wt. % solids content.

(35) Hardwood Pulp

(36) Once dried market eucalyptus pulp with a length weighted average fiber length of 0.81 mm.

(37) Softwood Pulp

(38) Once dried softwood pulp (pine) with a length weighted average fiber length of 2.39 mm.

(39) GCC, Hydrocarb® 60 (Available from Omya International AG, Switzerland)

(40) A dispersed ground calcium carbonate (GCC) pigment slurry with 78 wt. % solids content and a weight median particle size d.sub.50 of 1.6 μm was used.

(41) PCC, Syncarb® F0474 (Available from Omya International AG, Switzerland)

(42) A non-dispersed precipitated calcium carbonate (PCC) pigment slurry with 15 wt. % solids content and a weight median particle size d.sub.50 e of 2.7 μm was used.

(43) Percol® 1540, BASF (Germany)

(44) 2. Methods

(45) Preparing Microscopy Samples of Microfibrillated Cellulose (MFC) Produced in the Presence of Filler

(46) A small sample (0.1 g) of wet (ca. 55 wt. %) MFC-filler-compound (described in the material section) was placed into a glass beaker, and 500 ml of deionized water were added. A kitchen blender was used to assist in separating fibres and calcium carbonate particles. 2 ml of 10 wt. % hydrochloric acid were then added to dissolve the calcium carbonate, then the resulting mixture was mixes with the kitchen blender for 2 minutes. A few drops of this suspension was given on a glass microscope slide and dried in an oven at 120° C.

(47) Preparing Microscopy Samples of MFC

(48) Approximately 1 g of microfibrillated cellulose (MFC) without filler as described above in the material section (solids content of 3.8 wt.-%) was placed into a glass beaker, and 500 ml deionized water were added. A kitchen blender was used for 2 minutes to separate the fiber material. A few drops of this suspension were given on a glass microscope slide and dried in an oven at 120° C.

(49) Preparation of Hardwood Pulp

(50) Once dried eucalyptusus pulp was disintegrated according to ISO 5263-1 and diluted to a solids content of 1.5 wt.-%. No refining was applied.

(51) Preparation of Refined Hardwood Pulp

(52) Once dried eucalyptus pulp was disintegrated according to ISO 5263-1 and diluted to a solids content of 3 wt.-%. A laboratory disk refiner (Escher Wyss, now Voith, Germany) was used to prepare eucalyptusus pulp with a freeness of 30° SR.

(53) Preparation of Softwood Pulp

(54) Once dried softwood pulp was disintegrated according to ISO 5263-1 and diluted to a solids content of 1.5 wt.-%. No refining was applied.

(55) Preparation of Refined Softwood Pulp

(56) Once dried softwood pulp was disintegrated according to ISO 5263-1 and diluted to a solids content of 1.5 wt.-%. A laboratory disk refiner (Escher Wyss, now Voith, Germany) was used to prepare softwood pulp with a freeness of 25° SR.

(57) Preparing Furnish for Film Forming without MFC

(58) According to the formulations based on dry weight, hardwood pulp or hardwood pulp or softwood pulp or refined softwood pulp, eventual GCC and/or PCC particles as well as deionized water to obtain a final solids content of 1 wt. % were prepared in high shear conditions (Pendraulik, LD 50 Labordissolver, Pendraulik, Germany) with a mixing time of 15 minutes.

(59) Preparation of Liquid Suspension of the MFC Filler Compound

(60) Deionized water was added to the compound with a solids content of 55 wt. % in a quantity to obtain 10 wt. % solids content. High shear mixing (Pendraulik, LD 50 Labordissolver, Pendraulik, Germany) was applied for 15 minutes to disperse the compound, followed by further dilution with dionized water to a desired solid content level (5 wt.-%, 4 wt.-%, 2.5 wt.-%, 1 wt.-%) again with a 15 minutes high shear mixing step (Pendraulik, 2000 rpm).

(61) Preparation of Furnish for Film Forming with MFC Filler Compound

(62) According to the formulations based on dry weight, mixtures of the MFC filler compound suspension with 1 wt.-% solids content, hardwood pulp or softwood pulp and deionized water to obtain a final solids content of 1 wt.-% were prepared in high shear conditions (Pendraulik, LD 50 Labordissolver, Pendraulik, Germany) with a mixing time of 15 minutes.

(63) Preparation of MFC Suspension without Filler

(64) Deionized water was added to the MFC suspension in order to obtain desired solid content levels (2 wt.-%, 1 wt.-%), high shear mixing (Pendraulik, LD 50 Labordissolver, Pendraulik, Germany) was applied for 15 minutes to ensure proper mixing.

(65) Preparation of Furnish for Film Forming with MFC without Filler

(66) According to the formulations based on dry weight, mixtures containing MFC, PCC and/or GCC, eucalyptus pulp or softwood pulp as well as deionized water to obtain a final solids content of 1% were prepared in high shear conditions (Pendraulik, LD 50 Labordissolver, Pendraulik, Germany) with a mixing time of 15 minutes.

(67) MFC Filler Composite Films Produced with “Scandinavian Type” Laboratory Sheet Former

(68) A modified “Scandinavian Type” laboratory sheet former was used to produce films.

(69) An according quantity of the prepared furnish to obtain a film weight of usually 200 g/m.sup.2 was filled into the upper section which was tightly connected to a membrane as top part of a lower section. The top section was closed with a hood and an overpressure of 0.5 bar was applied to accelerate dewatering through the membrane. No agitation or further dilution was used. After forming the sheets were prepared as known in the art between two blotting papers and then pressed for 260 seconds at 420 kPa. A further hot press step with four sheets placed between two blotting papers and a temperature of 130° C. as well as a pressure of 95 kPa was used to dry the sheets. For physical testing, the sheets were placed in a conditioned room, for forming a wetting procedure was applied.

(70) MFC Filler Composite Films Produced with “Rapid Köthen Type” Laboratory Sheet Former

(71) A sheet forming procedure according to ISO 5269/2 “Preparation of laboratory sheets for physical testing—Part 2: Rapid Köthen method” was used with the following modifications: a wire with a mesh width of 50 μm was used. No water for dilution was added. No air for mixing was used. 5 seconds after filling the dewatering valve was opened and vacuum was applied for 25 seconds. The sheets were pressed with Sheet Press (PTI, Austria) and then dried between blotting papers at 115° C. for 8 minutes.

(72) Re-Wetting Sheets for Forming Trials

(73) Based on the present moisture content (100−solids content in wt. %), a desired amount of deionized water to obtain 6.25 wt.-%, 8 wt.-%, 10 wt.-%, 15 wt.-% or 20 wt.-% moisture content was sprayed at the MFC filler composite films by using an aerosol can. MFC filler composite films of the same composition and the same moisture level were stored for 24 hours in a closed plastic bag to ensure homogeneous distribution of humidity.

(74) 3D Forming

(75) For 3D forming a stack has to be prepared, from bottom to top: at first there is the bottom part of the platen press, followed by the aluminum die with the mold facing up, the sheet/film/material to be formed, a pile of rubber plates (3-4 for the 1 cm deep form, 5-6 for the 2 cm deep form) and finally the top part of the platen press. In the press used, the bottom part was moving and could be heated to a desired temperature. Before starting forming trials, the according die was placed in the heated press to get the desired temperature. Pressure, process dynamics (speed and time), temperature have to be adjusted accordingly.

(76) 3. Experiments

(77) a) Viscosities of MFC Suspensions

(78) TABLE-US-00001 TABLE 1 Solids Brookfield content of Spindle for Viscosity (at suspension Brookfield 100 rpm and Sample [wt.-%] mesaurement 25° C.) MFC filler compound suspension 10 No. 4 730 mPas MFC filler compound suspension 5 No. 2 50.0 mPas MFC filler compound suspension 2.5 No. 1 19.5 mPas MFC without filler 3.8 Not measurable MFC without filler 2 No. 6 1 800 mPas MFC without filler 1 No. 4 470 mPas

(79) b) MFC Filler Composite Sheet Material Properties at Different Moisture Levels

(80) The properties of the obtained sheet materials are also shown in FIG. 3.

(81) TABLE-US-00002 TABLE 2 normalized stretch Elongation increase per at break, Elongation level of 10% at break, moisture [% Formulation m.c..sup.[1] 20% m.c..sup.[1] per percent] Hardwood, 200 g/m.sup.2 2.1%  2.5% 0.04 Hardwood (refined), 3.0%  4.2% 0.12 200 g/m.sup.2 (A) Softwood (refined), 4.4%  5.6% 0.12 200 g/m.sup.2 (B) 80 wt. % Softwood 3.6%  4.1% 0.05 (refined) + 20 wt. % GCC, 200 g/m.sup.2 (C) 80 wt. % Softwood 3.3%  4.7% 0.14 (refined) + 20 wt. % PCC, 200 g/m.sup.2 (D) 60 wt. % Softwood 3.3%  4.6% 0.13 (refined) + 40 wt. % PCC, 200 g/m.sup.2 (E) 80 wt. % Softwood 3.3%  4.6% 0.13 (refined) + 20 wt. % PCC, 100 g/m.sup.2 (F) 5 wt. % Hardwood, 30 wt. % 7.3% 12.3% 0.5 MFC, 65 wt. % PCC, 200 g/m.sup.2 (G) 5 wt. % Hardwood, 45 wt. % 7.1% 10.2% 0.31 MFC, 50 wt. % PCC, 200 g/m.sup.2 (H) 20 wt. % Hardwood, 30 wt. % 4.9%  7.5% 0.26 MFC, 50 wt. % PCC, 200 g/m.sup.2 (I) .sup.[1]m.c.: moisture content

(82) c) 3D Forming Experiments

(83) (1) 3D Forming Parameters

(84) “Scandinavian type” laboratory sheets. Lower pressure in forming beneficial.

(85) TABLE-US-00003 TABLE 3 3D forming Molding Formulation parameters depth Result 90 wt. % MFC-filler compound, 10 wt. % 10 bar, 1 cm cracked Hardwood, 200 g/m.sup.2, 8% m.c. .sup.[1] 10 s, 70° C. 90 wt. % MFC-filler compound, 10 wt. % 10 bar, 1 cm cracked Hardwood, 200 g/m.sup.2, 8% m.c. .sup.[1] 7 s, 120° C. 90 wt. % MFC-filler compound, 10 wt. % 3.8 bar, 1 cm good Hardwood, 200 g/m.sup.2, 8% m.c. .sup.[1] 20 s, 70° C. 90 wt. % MFC-filler compound, 10 wt. % 3.8 bar, 1 cm good Hardwood, 200 g/m.sup.2, 8% m.c. .sup.[1] 10 s, 120° C. .sup.[1] m.c.: moisture content

(86) (2) Reference Samples

(87) “Rapid Köthen type” laboratory sheets.

(88) TABLE-US-00004 TABLE 4 3D forming Molding Formulation parameters depth Result Refined Hardwood, 0.05 wt. % Percol ® 3.8 bar, 1 cm cracked 1540 based on total dry weight of cellulose 10 s, material, 200 g/m.sup.2, 8% m.c. .sup.[1] 120° C. 80 wt. % refined Hardwood, 3.8 bar, 1 cm cracked 20 wt. % GCC, 0.05 wt. % 10 s, Percol ® 1540 based on total dry 120° C. weight of cellulose material and inorganic filler material, 200 g/m.sup.2, 8% m.c. .sup.[1] Refined Softwood, 3.8 bar, 1 cm good 0.05 wt. % Percol ® 1540 10 s, based on total dry weight of cellulose 120° C. material, 200 g/m.sup.2, 8% m.c. .sup.[1] 80 wt. % refined Softwood, 3.8 bar, 1 cm cracked 20 wt. % GCC, 0.05 wt. % 10 s, Percol ® 1540 based on total dry 120° C. weight of cellulose material and inorganic filler material, 200 g/m.sup.2, 8% m.c. .sup.[1] .sup.[1] m.c.: moisture content

(89) (3) Compound Series 1, Basic Conditions

(90) “Scandinavian type” laboratory sheets.

(91) TABLE-US-00005 TABLE 5 3D forming Molding Formulation parameters depth Result Hardwood, 200 g/m.sup.2, 3.8 bar, 1 cm cracked 8% m.c. .sup.[1] 10 s, 120° C. 5 wt. % Hardwood, 3.8 bar, 1 cm good 30 wt. % MFC, 65 wt. 10 s, % PCC, 200 g/m.sup.2, 8% m.c. .sup.[1] 120° C. 5 wt. % Hardwood, 3.8 bar, 1 cm o.k. 45 wt. % MFC, 50 wt. 10 s, cracking % PCC, 200 g/m.sup.2, 8% m.c. .sup.[1] 120° C. starting 20 wt. % Hardwood, 3.8 bar, 1 cm good 30 wt. % MFC, 50 wt. 10 s, % PCC, 200 g/m.sup.2, 8% m.c. .sup.[1] 120° C. .sup.[1] m.c.: moisture content

(92) (4) Compound Series 2, Forced Conditions and 15 wt. % Moisture Content

(93) “Scandinavian type” laboratory sheets.

(94) TABLE-US-00006 TABLE 6 3D forming Molding Formulation parameters depth Result Hardwood, 200 g/m.sup.2, 15% m.c. .sup.[1] 3.8 bar, 2 cm cracked 10 s, 120° C. 5 wt. % Hardwood, 30 wt. 3.8 bar, 2 cm o.k., % MFC, 65 wt. 10 s, not fully % PCC, 200 g/m.sup.2, 15% m.c. .sup.[1] 120° C. formed .sup.[1] m.c.: moisture content

(95) (5) Compound Series 3, Forced Conditions and 20 wt. % Moisture Content

(96) “Scandinavian type” laboratory sheets.

(97) TABLE-US-00007 TABLE 7 3D forming Molding Formulation parameters depth Result Hardwood, 200 g/m.sup.2, 20% m.c. .sup.[1] 3.8 bar, 2 cm cracked 10 s, 120° C. 5 wt. % Hardwood, 30 wt. 3.8 bar, 2 cm o.k., % MFC, 65 wt. 10 s, not fully % PCC, 200 g/m.sup.2, 20% m.c. .sup.[1] 120° C. formed .sup.[1] m.c.: moisture content

(98) (6) Compound Series 4, Forced Conditions, Different Compositions at 10 wt. % Moisture Content

(99) “Scandinavian type” laboratory sheets.

(100) TABLE-US-00008 TABLE 8 3D forming Molding Formulation parameters depth Result 5 wt. % Hardwood, 6.0 bar, 2 cm cracked 30 wt. % MFC, 65 wt. 10 s, % PCC, 200 g/m.sup.2, 10% m.c. .sup.[1] 120° C. 5 wt. % Hardwood, 6.0 bar, 2 cm cracked 45 wt. % MFC, 50 wt. 10 s, % PCC, 200 g/m.sup.2, 10% m.c. .sup.[1] 120° C. 20 wt. % Hardwood, 6.0 bar, 2 cm cracked 30 wt. % MFC, 50 wt. 10 s, % PCC, 200 g/m.sup.2, 10% m.c. .sup.[1] 120° C. .sup.[1] m.c.: moisture content

(101) (7) Compound Series 5, Forced Conditions, Different Compositions at 20 wt. % Moisture Content

(102) “Scandinavian type” laboratory sheets.

(103) TABLE-US-00009 TABLE 9 3D forming Molding Formulation parameters depth Result 5 wt. % Hardwood, 6.0 bar, 2 cm good 30 wt. % MFC, 65 wt. 10 s, % PCC, 200 g/m.sup.2, 20% m.c. .sup.[1] 120° C. 5 wt. % Hardwood, 6.0 bar, 2 cm cracked 45 wt. % MFC, 50 wt. 10 s, % PCC, 200 g/m.sup.2, 20% m.c. .sup.[1] 120° C. 20 wt. % Hardwood, 6.0 bar, 2 cm o.k, 30 wt. % MFC, 50 wt. 10 s, not fully % PCC, 200 g/m.sup.2, 20% m.c. .sup.[1] 120° C. formed .sup.[1] m.c.: moisture content