FI20245652A1

FI20245652A1 - A process for preparing a moulded product and a moulded product

Info

Publication number: FI20245652A1
Application number: FI20245652A
Authority: FI
Inventors: Del Cerro Daniel Rico; Heet Chauhan
Original assignee: Upm Kymmene Corp
Priority date: 2024-05-22
Filing date: 2024-05-22
Publication date: 2025-11-23
Also published as: WO2025242965A1

Abstract

A process for preparing a moulded product (1) is disclosed. The process may comprise providing a plurality of webs (2, 2’, 2’’) of dry cellulosic fiber material, each of the webs having two sides (3, 4, 3’, 4’, 3’’, 4’’), such that each of the webs is unwound from a roll of the dry cellulosic fiber material; feeding the plurality of the webs such that a side (3, 3’’) of each of the webs and a side (3’, 4’) of another web face each other, said sides facing each other forming a pair of sides; applying a first chemical (6) on the sides forming the pair of sides in each of the pair of sides; calendering the plurality of the webs together, thereby obtaining a calendered web (8); applying a second chemical (9) on an outer side of the calendered web; optionally pre-cutting (12) the calendered web into a calendered sheet and/or shape (13) prior to the hot pressing (14); and hot pressing the calendered web, sheet or shape, thereby obtaining the moulded product.

Description

A PROCESS FOR PREPARING A MOULDED PRODUCT AND A MOULDED

PRODUCT

TECHNICAL FIELD

The present disclosure relates to a process for preparing a moulded product and to a moulded product.

BACKGROUND

There is an increasing market for three-dimen- sional moulded products formed from renewable, non-fos- sil and recyclable sources, such as cellulosic fibres.

Such products may be formed using a wet mould- ing process, for example by extruding or injecting a wet pulp slurry into a mould and by evaporating the liquid (typically water), or by One-cast, transfer molding, or thermoforming. However, for environmental reasons, there may be a need to reduce water consumption. Fur- ther, processes that involve drying or milling steps may consume significant amounts of energy.

To reduce water consumption, it is also possi- ble to form such moulded products using a dry moulding process. However, dry moulding processed currently available may have their own disadvantages.

SUMMARY a A process for preparing a moulded product is

S disclosed. The process may comprise ro providing a plurality of webs of dry cellulosic

N fiber material, each of the webs having two sides, such r 30 that each of the webs is unwound from a roll of the dry x cellulosic fiber material;

N feeding the plurality of the webs such that a 3 side of each of the webs and a side of another web face

O each other, said sides facing each other forming a pair of sides;

applying a first chemical on the sides forming the pair of sides in each of the pair of sides; calendering the plurality of the webs together, thereby obtaining a calendered web; applying a second chemical on an outer side of the calendered web; optionally pre-cutting the calendered web into a calendered sheet and/or shape prior to the hot pressing; and hot pressing the calendered web, sheet or shape, thereby obtaining the moulded product.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the embodiments and constitute a part of this specification, illustrate various embodiments. In the drawings:

Fig. 1 illustrates an embodiment of the process for preparing a moulded product;

Fig. 2 illustrates another embodiment of the process for preparing a moulded product; and

Fig. 3 shows a moulded product in cross- sectional view.

DETAILED DESCRIPTION a A process for preparing a moulded product is

N 30 fiber material, each of the webs having two sides, such

I that each of the webs is unwound from a roll of the dry x cellulosic fiber material;

D feeding the plurality of the webs such that a

O side of each of the webs and a side of another web face

O 35 each other, said sides facing each other forming a pair of sides;

applying a first chemical on the sides forming the pair of sides in each of the pair of sides; calendering the plurality of the webs together, thereby obtaining a calendered web; applying a second chemical on an outer side of the calendered web; optionally pre-cutting the calendered web into a calendered sheet and/or shape prior to the hot pressing; and hot pressing the calendered web, sheet and/or shape, thereby obtaining the moulded product.

A moulded product comprising a plurality of layers of cellulosic fiber material is also disclosed.

A moulded product obtainable by the process according to one or more embodiments described in this specification is also disclosed.

Any embodiments described in this specification may be understood as being disclosed in the context of the process as well as of the moulded product.

In the hot pressing, the calendered web, sheet and/or shape may be heated to a forming temperature and pressed at a pressure to form the moulded product. With the hot pressing, the moulded product may thus be shaped into a desired three-dimensional shape. The hot pressing may comprise cutting and moulding the calendered web, sheet and/or shape into the desired three-dimensional

N shape, thereby obtaining the moulded product. The hot

N pressing may comprise cutting the calendered web, sheet 3 30 and/or shape into a desired two-dimensional shape and

N moulding the desired two-dimensional shape into the

E desired three-dimensional shape, thereby obtaining the * moulded product. The mould used in the hot pressing may 0 be configured to cut the calendered web, sheet and/or 3 35 shape into the desired shape, such as the desired two-

S dimensional shape.

The process is relatively fast and easily scalable.

The process is a dry moulding process.

Therefore the consumption of water is low. Further, the consumption of energy may be reduced, as there is typically little or no need to remove water from the cellulosic fiber material at any stage of the process.

The plurality of sheets may be calendered together without any milling or refining of the cellulosic fiber material between the providing of the plurality of the webs and the calendering of the plurality of the webs together.

As the process does not necessarily include milling or refining of the cellulosic fiber material, the consumption of energy may be reduced. This may also reduce dusting and the production of very short fibers or fines, which could cause issues in the process and/or in the moulded product. Further, the process does not require a vacuum. The safety aspects of the process may thus also be improved.

The cellulosic fiber material may thus be unmilled and/or unrefined.

There is also no need for an additional support layer, for example a tissue paper layer, when forming the webs. Thus the moulded product does not need to comprise a tissue paper layer.

The moulded product may have desired

N properties, such as water barrier properties.

N The plurality of the webs may be understood as 3 30 referring to at least two webs, or at least three webs.

N When there are two or more webs calendered together, the

E mechanical strength of the moulded product will be * improved. The exact number of the plurality of the webs 0 may be selected based e.g. on the grammage of each of 3 35 the webs and/or on the desired thickness of the moulded < product.

In other words, the process may comprise providing two or more (or three or more) of webs of dry cellulosic fiber material, each of the webs having two sides, such that each of the webs is unwound from a roll of the dry cellulosic fiber material; 5 feeding the two or more (or three or more) of the webs such that a side of each of the webs and a side of another web face each other, said sides facing each other forming a pair of sides; applying a first chemical on the sides forming the pair of sides in each of the pair of sides; calendering the two or more (or three or more) of the webs together, thereby obtaining a calendered web; applying a second chemical on an outer side of the calendered web; optionally pre-cutting the calendered web into a calendered sheet and/or shape prior to the hot pressing; and hot pressing the calendered web, sheet and/or shape, thereby obtaining the moulded product.

Fach of the webs may be arranged in a roll.

The cellulosic fiber material may comprise or be pulp; wood pulp; fluff pulp; pre-treated pulp; paper and/or paperboard-grade pulp; or any mixture or combination thereof. In principle, any pulp grades suitable for paper and/or paperboard manufacture may be used as the cellulosic fiber material.

N The pre-treated pulp may be pre-treated e.g.

N by modifying (or reducing) the chain length of the 3 30 cellulose contained in the pulp. The pulp may have been

N pre-treated by treating enzymatically, chemically

T and/or physically so as to partially hydrolyse cellulose * contained therein to reduce chain length of the 0 cellulose. For example, the pre-treated pulp may 3 35 comprise or be pulp that has been subjected to acid

S hydrolysis, other type of hydrolysis or any other treatment capable of cleaving alycosidic bonds of the cellulose in the pulp. In some embodiments, the pre- treated pulp may be refined (i.e. mechanically pre- treated). The refining may increase fibrillation, which may increase the binding strength and/or barrier properties, such as air barrier properties. The fibrillation may increase the number of free hydroxyl groups and/or surface area on the surface(s) of the pre- treated pulp and may thereby assist in fiber-fiber bonding. The pulp may have been pre-treated before it has been arranged to the roll (s).

Fluff pulp may be particularly well suited for the present process. However, the pulp grade may depend e.g. on the type of moulded product to be produced by the process. For example, for moulded products such as cups, fluff pulp may be well suited. For relatively thin moulded products, such as lids, wood pulp, for example paper and/or paperboard-grade pulp, may be well suited.

The cellulosic fiber material may thus be fluff pulp. The dry fluff pulp may be provided as a plurality of webs such that each web of the plurality of the webs is unwound from a roll of the dry fluff pulp. The fluff pulp may be pre-treated, for example by any pretreatment described above.

Fluff pulp may be understood as referring to a pulp suitable for fibrillating, e.g. by shredding. Fluff pulp typically comprises pulp from long fibre softwoods.

It is typically intended for applications that require

N high absorbency, such as a raw material in the absorbent

N core of personal care products such as diapers, feminine 3 30 hygiene products, and/or air-laid absorbent towelling,

N as such, or with superabsorbents and/or synthetic

E fibres. The density of fluff pulp may be e.g. in the * range of 0.4-0.65 kg/cm?®. 0 Each of the webs may have a grammage of e.g. 3 35 about 650 — 850 g/m?, for example preferably about 700 < = 800 g/m?, or more preferably about 750 g/m?. However, the grammage is not particularly limited.

The first chemical may comprise or be a chemical for improving the binding of the plurality of the webs to each other and/or for improving the mechanical strength of the moulded product.

The first chemical may comprise or be e.g. starch, modified starch, or any mixture or combination thereof. The starch may be e.g. potato starch, corn starch, or any mixture or combination thereof. However, other starch grades may also be contemplated. The modified starch may include e.g. enzymatically, chemically and/or physically treated, for example partially hydrolyzed, starch. Starch may be enzymatically, chemically and/or physically treated or otherwise partially hydrolyzed to reduce chain length and thereby improve penetration. The modified starch may comprise or be anionically and/or cationically modified starch.

The first chemical may be applied e.g. by spraying. However, other methods to applying the first chemical may be contemplated, for example curtain application and/or using nip rolls. The first chemical may be applied e.g. by spraying or otherwise applying a solution or dispersion of the first chemical. The concentration of the first chemical in the solution or dispersion may be e.g. in the range of about 1 - 10 3 (w/w); preferably in the range of about 3 - 6 % (w/w); or more preferably in the range of about 2.7 - 5.4 3

N (w/w). Solutions or dispersions containing the first

N chemical at a high solids content may be guite viscous 3 30 and thereby challenging to apply e.g. by spraying.

N However, a low solids content may add significant

T amounts of water to the web(s), which may be a undesirable. The first chemical may be applied as an

O amount of about 1 - 5 g/m?; preferably in an amount of 3 35 about 1 - 3 g/m?. Suitable concentrations and amounts < applied may depend e.g. on the type or quality of the first chemical, for example the quality of starch. A skilled person is capable of selecting a suitable concentration and/or amount of the first chemical as well as a suitable method for applying it.

The first chemical may be applied to both of the sides forming the pair of sides in each of the pair of sides. This may improve the binding of the plurality of the webs together.

As a skilled person will understand, the plurality of the webs calendered together in the calendered web will eventually form the plurality of the layers of the moulded product.

The calendering of the plurality of the webs together may improve the binding of the plurality of the webs, and thereby the layers of the moulded product, to each other. A nip load e.g. in the range of about 10 - kN/m may be used in the calendering. However, the parameters of the calendering are not particularly limited. The calendering may merely press the webs slightly together, as the web, sheet or shape may be hot 20 pressed thereafter.

The second chemical may comprise or be a chemical for improving the water barrier properties of the moulded product.

The second chemical may comprise or be e.g. alkyl ketene dimer (AKD); alkenyl succinic anhydride (ASA); polyvinyl alcohol (PVA); a combination of polyhydroxybutyrate (PHB) and alkyl ketene dimer; a wax;

N or any combination or mixture thereof. The wax may be a

N natural wax. AKD is well suited as the second chemical, 3 30 but other chemicals, including the above, may well be

N contemplated.

E The second chemical may be applied e.g. by * spraying. However, other methods to applying the second 0 chemical may be contemplated, for example curtain 3 35 application and/or using nip rolls. The second chemical

S may be applied e.g. by spraying or otherwise applying a solution or dispersion of the first chemical. The concentration of the second chemical in the solution or dispersion may be e.g. in the range of about 0.1 - 5 % (w/w). The second chemical may be applied e.g. as an amount of about 0.1 — 0.5 g/m?, for example when the second chemical is or comprises AKD. However, suitable concentrations and amounts applied may depend e.g. on the type or quality of the second chemical, for example the quality and/or chain length of the AKD. A skilled person is capable of selecting a suitable concentration and/or amount of the second chemical.

The calendered web may have two outer sides.

The second chemical may be applied on one of the outer sides, or on both outer sides of the calendered web.

The second chemical may provide water barrier properties to the outer side(s) of the moulded product on which it has been applied.

In some embodiments, the cellulosic fiber material does not comprise any thermoplastic material.

This may depend e.g. on the selection of the second chemical. For example, in embodiments in which the cellulosic fiber material does not comprise any thermoplastic material, the second chemical may comprise or be e.g. alkyl ketene dimer (AKD); alkenyl succinic anhydride (ASA); a wax; or any combination or mixture thereof.

The process may further comprise curing the calendered web, sheet and/or shape prior to the hot

N pressing. In the curing, the first chemical and/or the

N second chemical may be cured. The calendered web, sheet 3 30 and/or shape may be cured e.g. at a temperature of at

N least about 105 °C, or at a temperature in the range of

E about 105 —- 150 °C, preferably about 120 - 140 °C, or * more preferably about 130 °C, prior to the hot pressing. 0 However, in some embodiments, the curing may not be 3 35 necessary, for example when no water 1s added to the < calendered web, sheet and/or shape (in addition to the application of the first and the second chemical). The hot pressing may, in such embodiments, suffice to cure the first chemical and/or the second chemical and thus allow obtaining a desired moulded product.

The moisture content of the plurality of the webs and/or of the calendered web may be e.g. up to 6 % (w/w), or in the range of 4 — 6 % (w/w). However, the ambient conditions may affect the moisture content of the webs.

In the hot pressing, the calendered web, sheet and/or shape may be heated to a forming temperature of e.g. about 105 — 140 °C.

The temperature of the hot pressing may affect the quality of the moulded product. For example, temperatures that are too high or too low may cause e.g. blistering.

In the hot pressing, the calendered web, sheet and/or shape may be pressed e.g. at a pressure of about 50 — 100 bar, preferably about 60 — 65 bar.

The pressure of the hot pressing may also affect the quality of the moulded product.

In the hot pressing, the calendered web, sheet and/or shape may be pressed for a time period of e.g. about 0.5 — 5 s, or preferably about 1 - 3 s.

The hot pressing may produce a moulded product that has a smooth surface. Both outer sides of the moulded product may have a smooth surface.

The hot pressing may apply ramping to the

N temperature and/or the pressure, i.e. the temperature

N and/or the pressure may be increased at a predefined 3 30 rate during the hot pressing. Additionally or

N alternatively, pressure may be gradually reduced in

T order to release any entrapped steam. * After the hot pressing, the residue remaining 0 from the calendered web, sheet and/or shape that has not 3 35 been incorporated into the moulded product may be

S disposed of and/or recycled for other uses.

The moulded product may comprise a first chemical between the plurality of layers for improving the binding of the plurality of layers to each other and/or for improving the mechanical strength of the moulded product. The first chemical may comprise or be any first chemical described in this specification. For example, the first chemical may comprise or be starch or modified starch.

In the context of the moulded product, the layers are not necessarily present as distinct layers, i.e. as layers distinguishable (or easily distinguishable) from each other. It may be that they are fused together such that individual layers are not visible in the moulded product. However, it may still be possible to distinguish or separate individual layers in the moulded product, for example in a laboratory.

The cellulosic fiber material may comprise or be any cellulosic fiber material described in this specification, e.g. fluff pulp.

The moulded product may be obtainable by the process according to one or more embodiments described in this specification.

The moulded product may be a dry moulded product. The moulded product may be a hot pressed product.

The moulded product may be cutlery (e.g. a spoon, a fork, or a knife); a receptacle; a tray; a cup;

N a bowl; a plate; a lid; or packaging material.

N

S 30

N EXAMPLES

= Reference will now be made in detail to various - embodiments, an example of which is illustrated in the

D accompanying drawings. 3 35 The description below discloses some

S embodiments in such a detail that a person skilled in the art is able to utilize the embodiments based on the disclosure. Not all steps or features of the embodiments are discussed in detail, as many of the steps or features will be obvious for the person skilled in the art based on this specification.

Figure 1 illustrates an embodiment of the process for preparing a moulded product 1.

A plurality of webs 2, 2’, i.e. a first web 2 and a second web 2’, of dry cellulosic fiber material are provided. Each of the webs 2, 2’ has two sides 3, 4, 3', 4". The first web 2 has a first side 3 and a second side 4; the second web 2’ has a first side 3” and a second side 4’. In this embodiment, two webs 2, 2” (i.e. at least two webs) are provided, but a skilled person will understand that e.g. three or more webs could be provided in a similar manner. Each of the plurality of webs 2, 2’ is unwound from a roll 5, 5’ of the dry cellulosic fiber material. The first web 2 is unwound from a first roll 5, and the second web 2’ is unwound from a second roll 5’. The dry cellulosic fiber material may be pulp, e.g. fluff pulp, but various other pulp grades may be contemplated, including any cellulosic fiber material described in this specification.

The plurality of the webs 2, 2’ are fed such that a side 3 of each of the webs 2 and a side 3’ of another web 2’ (i.e. another one of the webs) face each other, said sides 3, 3’ facing each other forming a pair

N of sides. As there are two webs in this exemplary

N embodiment, a side 3 of one of the webs 2 and a side 3” 3 30 of the other web 2” face each other, said sides 3, 3”

N facing each other forming a pair of sides. In other

E words, the first side 3 of the first web 2 faces the > first side 3' of the second web 27, said first sides 3,

D 3’ facing each other forming a pair of sides. 3 35 A first chemical 6 is applied on the sides 3,

S 3' forming the pair of sides in each of the pair of sides, i.e. on the first sides 3, 3’. The first chemical

6 may comprise or be any first chemical described in this specification. The first chemical 6 is illustrated here as being applied by spraying, although additionally or alternatively, other application methods could be used.

The plurality of the webs 2, 2’ are then calendered together using a calender 7. A calendered web 8 is thus obtained.

A second chemical 9 is applied on an outer side 10, 10" of the calendered web 8. In this embodiment, the second chemical 9 is applied on both of the outer sides 10, 10 of the calendered web 8; however, it may alternatively be applied on only one of the outer sides 10, 107 of the calendered web 8, if there is e.g. no need to impart water barrier properties to both sides of the moulded product 1. The second chemical 9 is illustrated here as being applied by spraying, although other application methods could, additionally or alternatively, be used.

At 11, the calendered web 8, i.e. the first chemical 6 and the second chemical 9 applied therein, may be cured. The calendered web 8 may be cured e.g. at a temperature of at least 105 °C, or at a temperature in the range of 105 —- 150 °C. However, in some embodiments, the curing may not be necessary, for example when no water is added to the calendered web 8 (in addition to the application of the first chemical 6

N and the second chemical 9). The curing at 11 is thus

N optional. 3 30 At 12, the calendered web 8 may be pre-cut into

N a calendered sheet and/or shape 13. For example, the

T calendered web 8 may be pre-cut into a calendered sheet * 13 to facilitate hot pressing at 14. The pre-cutting at 0 12 is however also optional, in which case the 3 35 calendered web 8 would proceed to hot pressing at 14.

O

N

In some embodiments, the curing at 11 may take place after the pre-cutting at 12. In such embodiments, the calendered sheet and/or shape 13 may be cured at 11.

At 14, the calendered web, sheet and/or shape 8, 13 is hot pressed, thereby obtaining the moulded product 1. In this example, the moulded product 1 is cutlery, i.e. one or more pieces of cutlery, which has a three-dimensional shape. A residue 15 remaining from the calendered web, sheet and/or shape 8, 13 that has not been incorporated into the moulded product 1, is also obtained form the hot pressing at 14. The residue may be disposed of or recycled for other uses, for example in another process 16.

Figure 2 illustrates another embodiment of the 15 process for preparing a moulded product 1.

The process of Fig. 2 is similar to the process shown in Fig. 1, except that the plurality of webs 2, 2", 2'7, includes three webs (i.e. at least three webs).

In other words, a first web 2, a second web 2’, and a third web 2’’ of dry cellulosic fiber material are provided. Each of the webs 2, 2’, 2’’ has two sides 3, 4, 37, 47, 37/7, 417. The first web 2 has a first side 3 and a second side 4; the second web 2’ has a first side 3' and a second side 4’; and the third web 2’’ has a first side 3'/ and a second side 477. In this embodiment, there are three webs 2, 2’, 2/7, but a skilled person will understand that e.g. four or more webs could be

N provided in a similar manner. Thus at least the first

N web 2, the second web 2’ and the third web 2, are 3 30 provided. Each of the plurality of the webs 2, 27, 2’

N is unwound from a roll 5, 5’, 5’’ of the dry cellulosic

T fiber material. The first web 2 is unwound from a first - roll 5, the second web 2’ is unwound from a second roll

D 5’, and the third web 277 is unwound from a third roll 3 35 577. The dry cellulosic fiber material may be pulp, e.g. < fluff pulp, but various other pulp grades may be contemplated.

The plurality of the webs 2, 2’, 2'’, i.e. the first web 2, the second web 2’ and the third web 277, are fed such that the first side 3 of the first web 2 faces the first side 3’ of the second web 2’, said first sides 3, 3’ facing each other forming a first pair of sides; and the first side 37” of the third web 2’’ faces the second side 4’ of the second web 2’, said sides 3/', 4' forming a second pair of sides. In other words, a side 3, 4” of each of the webs 2, 2’ and a side 37, 37’ of another one of the webs 2’, 2'’ face each other, said sides facing each other forming a pair of sides. The pairs of sides thus formed include the pair formed by the sides 3 and 3’, and the pair formed by the sides 3” and 47.

A first chemical 6 is applied on the sides 3, 3' forming the pair of sides in each of the pair of sides, i.e. on the first sides 3, 3’ facing each other forming the first pair of sides. The first chemical 6 is also applied on the sides 3’’, 4’ forming the second pair of sides.

The plurality of the webs 2, 2’, 2’’ are then calendered together using a calender 7. A calendered web 8 is thus obtained.

The following stages of the process may be similar to the ones illustrated in Fig. 1, except that the optional curing at 11 is not shown in this figure for simplicity. However, the curing at 11 could also be

N included in the process of Fig. 2, if desired.

N Figure 3 shows a moulded product 1 in cross- 3 30 sectional view. The moulded product 1 comprises a

N plurality of layers 17, 17’, 177, of cellulosic fiber

E material. The cellulosic fiber material may be any > cellulosic fiber material described in this

D specification. Although three layers 17, 17’, 17'’ are 3 35 shown, it should be understood that there could

I alternatively be two layers, or four or more layers in the moulded product 1.

Although the layers are depicted as distinctive layers 17 17’, 17’’ in Figure 3, it could be that they are so well fused together that individual layers are not visible in the moulded product 1.

The moulded product 1 further comprises a first chemical between the plurality of layers 17, 17’, 17'7 for improving the binding of the plurality of layers to each other and/or for improving the mechanical strength of the moulded product 1. However, the first chemical is not visible in this figure, as it is incorporated into the structure of the moulded product 1 and absorbed to the cellulosic fiber material of the layers 17, 17', 177” at least partially. The first chemical thus binds, or assists in binding, the layers 17, 17, 17'' together.

The moulded product 1 has at least one outer side, or outer sides 18, 187.

The moulded product 1 further comprises a second chemical on an outer side 18, 18’ of the plurality of the layers 17, 177, 1777. The second chemical may be applied on both of the outer sides 18, 18’ or only on one of the outer sides 18, 18’. Again the second chemical is not visible in this figure, as it is incorporated into the structure of the moulded product 1 and absorbed to the cellulosic fiber material of the layers 17 and/or 17” at least partially. The second chemical may impart a water barrier on the moulded product 1, i.e. on the

N outer side(s) 18, 187 on which it has been applied.

N The moulded product 1 may be a hot pressed 3 30 product.

N The moulded product 1 may be obtainable e.g.

T by the processes illustrated in Figs. 1 and 2. The * plurality of layers 17, 17’, 177, may be derived from 0 three webs of the cellulosic fiber material, such as the 3 35 webs 2, 27, 2'' illustrated in Fig. 2. < The shape of the moulded product 1 is not particularly limited. The moulded product 1 may be e.g.

a receptacle or a piece of cutlery, or any other moulded product described in this specification.

EXAMPLE 1

A process similar to the one illustrated in

Fig. 1 was employed for producing moulded products from two pulp webs unwound from rolls ("UPM BioBright”,

BioBright Airlaid and Biosmart 20; non fluff was also tested but fluff pulp was preferred). The webs had a grammage of 750 g/m? and were 1.25 mm thick.

Starch (cationic starch, Vector IC 27216 from

Roguette commercially available with a 27 % (w/w) solid content, i.e. 27 % (w/w) of the starch based on the total weight of the solution) was tested at different dilutions as the first chemical and spraved on the sides of the webs facing each other. The two webs were calendered together, and AKD as the second chemical was sprayed on the calendered web. Product samples were hot pressed from the calendered web for a 1-3 s pressing time. The parameters of the trial are shown in Table 1.

Table 1. Parameters of the trial - Various concentrations starch solutions were investigated.

Curing

Starch AKD water Speci- | pre- para- Description (Roguette) | (%) (gsm) mens cuts meters dilution Original <t

N 10 times starch

N

' (2.7 % 18 solution, 8 45 i solid more water

N tent) 130 %c conten spray r | | 7.1% | & 45 a dilution 7 . mins Same starch

N times .

O solution

O ~3.9 % 30 27 54 2 | with less

N solid

O water

N content)

No major differences in binding strength of the layers of the products between the different starch concentrations were observed. Water sprayed on the calendered web were found to cause blisters in the product samples after the hot pressing.

EXAMPLE 2

Product samples were produced essentially as described in Example 1, except that a different starch (modified starch, C* Film Starch 03711) was tested to assess binding strength. The starch was diluted to a concentration of 2.7-3 % (w/w, solid content) prior to application to the webs. Approx. 1.56 g/m? of the starch was sprayed on both sides of the pulp webs.

The binding strength of the layers was found to be improved as compared to the samples produced in

Fxample 1. This may be because the modified starch used in this Example showed better penetration to the webs and therefore improved the binding strength.

EXAMPLE 3

Product samples were produced essentially as described in Examples 1 and 2. AKD (Solenis J220; hexanedioic acid, polymer with N-(2-aminoethyl)-1,2- ethanediamine and (chloromethyl)oxirane, CAS number

N 25212-19-5) was applied as the second chemical with the

N goal to have a water barrier while minimizing the amount 3 30 of AKD applied. Table 2 shows the parameters used in the

N process. 7

Table 2. AKD quantities investigated. 3 03711) (%) * parameters

Solid content applied in [7.1 —|130 °C & 45 pulp sheet ~2.7 % mins

Water barrier properties of the product samples were investigated by placing water and acid solution droplets on the surfaces of the product samples and determining how long the droplets remained on the surfaces. 0.3 g/m? of 1 % (solid content) AKD was found to ensure surface hydrophobicity. It held water on the surface up to 3h. Additionally, a mixture of organic acids (phosphoric acid & nitric acid) was also held on surface (tested only for 20 minutes) without apparent issues. 0.4 % AKD, corresponding to approx. 0.1 g/m?, also performed very well, holding water droplets up to 1h.

It is obvious to a person skilled in the art that with the advancement of technology, the basic idea may be implemented in various ways. The embodiments are thus not limited to the examples described above; instead they may vary within the scope of the claims.

The embodiments described hereinbefore may be used in any combination with each other. Several of the embodiments may be combined together to form a further + embodiment. A process, a product, or a use, disclosed

S 25 herein, may comprise at least one of the embodiments

O described hereinbefore. It will be understood that the = benefits and advantages described above may relate to

N one embodiment or may relate to several embodiments.

E The embodiments are not limited to those that solve any

N 30 or all of the stated problems or those that have any or

O all of the stated benefits and advantages. It will

N further be understood that reference to 'an' item refers

N to one or more of those items. The term "comprising” is used in this specification to mean including the feature(s) or acts) followed thereafter, without excluding the presence of one or more additional features or acts. i

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Claims

1. A process for preparing a moulded product, wherein the process comprises providing a plurality of webs of dry cellulosic fiber material, each of the webs having two sides, such that each of the webs is unwound from a roll of the dry cellulosic fiber material; feeding the plurality of the webs such that a side of each of the webs and a side of another web face each other, said sides facing each other forming a pair of sides; applying a first chemical on the sides forming the pair of sides in each of the pair of sides; calendering the plurality of the webs together, thereby obtaining a calendered web; applying a second chemical on an outer side of the calendered web; optionally pre-cutting the calendered web into a calendered sheet and/or shape prior to the hot pressing; and hot pressing the calendered web, sheet or shape, thereby obtaining the moulded product.

2. The process according to claim 1, wherein the cellulosic fiber material comprises or is pulp; wood pulp; fluff pulp; pre-treated pulp; paper and/or paperboard-grade pulp; or any mixture or combination s thereof. Ed

3. The process according to claim 1 or 2, LÖ wherein the cellulosic fiber material is fluff pulp, and = 30 wherein the dry fluff pulp is provided as the plurality N of the webs such that each of the plurality of the webs E is unwound from a roll of the dry fluff pulp.

N

4. The process according to any one of claims © 1 - 3, wherein the first chemical comprises or is a N 35 chemical for improving the binding of the plurality of N the webs to each other and/or for improving the mechanical strength of the moulded product.

5. The process according to any one of claims 1 - 4, wherein the first chemical comprises or is starch, modified starch, or any mixture or combination thereof.

6. The process according to any one of claims 1 - 5, wherein the second chemical comprises or is a chemical for improving the water barrier properties of the moulded product.

7. The process according to any one of claims 1 - 6, wherein the second chemical comprises or is alkyl ketene dimer; alkenyl succinic anhydride; polyvinyl alcohol; a combination of polyhydroxybutyrate and alkyl ketene dimer; a wax; or any combination or mixture thereof.

8. The process according to any one of claims 1 - 7, wherein the calendered web, sheet and/or shape is cured at a temperature of at least 105 °C, or at a temperature in the range of 105 —- 150 °C, prior to the hot pressing.

9. The process according to any one of claims 1 - 8, wherein the plurality of the webs refers to at least two, or at least three webs.

10. The process according to any one of claims 1 - 9, wherein the moisture content of the plurality of the webs and/or of the calendered web is up to 6 % (w/w), or in the range of 4 - 6 % (w/w).

11. The process according to any one of claims 1 - 10, wherein in the hot pressing, the calendered web, N sheet and/or shape is heated to a forming temperature N of about 105 - 140 °C. 3 30

12. The process according to any one of claims N 1 - 11, wherein in the hot pressing, the calendered web, T sheet and/or shape is pressed at a pressure of about 50 ” — 100 bar, or about 60 — 65 bar. D

13. The process according to any one of claims 3 35 1 - 12, wherein the moulded product is cutlery; a < receptacle; a tray; a cup; a bowl; a plate; a lid; or packaging material.

14. A moulded product comprising a plurality of layers of cellulosic fiber material; a first chemical between the plurality of layers for improving the binding of the plurality of layers to each other and/or for improving the mechanical strength of the moulded product, wherein the first chemical comprises or is starch or modified starch; and a second chemical on an outer side of the plurality of the layers.

15. The moulded product according to claim 14, wherein the cellulosic fiber material comprises or is fluff pulp.

16. The moulded product according to claim 14 or 15, wherein the moulded product is obtainable by the process according to any one of claims 1 — 13. i N O N LÖ ? N N I [an a N O O O + N O N