Molded tray and preparation method thereof

Abstract

The invention belongs to the technical field of molded trays, and particularly relates to a molded tray and a preparation method thereof. The molded tray provided by the invention can effectively improve the performance of the plate, reduce the density of the plate and effectively optimize the application performance of the tray. The production process of the mould pressing tray comprises the technological processes of wood shaving preparation, wood shaving drying, wood shaving sizing, mould pressing forming and the like. The raw materials mainly comprise wood shavings and an adhesive. According to the invention, the density is reduced and the mechanical property of the tray is improved mainly by optimally controlling the ratio of wood shaving raw materials and the shape of the wood shavings and matching with a special adhesive system, so that the raw material and production cost can be greatly reduced, and the transportation cost is further reduced; and meanwhile, no aldehyde-containing additive is added in the production process, so that the product is more environment-friendly and healthy.

Description

Technical Field

[0001] This application belongs to the field of molded tray technology, specifically relating to a molded tray and its preparation method. Background Technology

[0002] Molded pallets are a new type of product made from wood, straw, peanut shells, cotton stalks, and bamboo. These materials are crushed, cut into shavings, dried, and then molded under high temperature and pressure with the application of adhesives. With the rapid development of the global packaging industry, pallets, as an important form of packaging, play an irreplaceable role in modern logistics. Molded pallets, as a cost-effective, efficient, and practical product, can meet the handling and storage needs of docks, freight yards, warehouses, workshops, shopping malls, and other locations.

[0003] However, molded pallets used in existing technologies often lack sufficient strength and have poor compatibility with the fork arms. When the fork arms are too short or do not insert deeply enough into the pallet, the portion of the pallet extending beyond the fork arms can break under the pressure of heavy objects, affecting the pallet's reusability. Therefore, it is necessary to optimize and improve pallet strength. Existing technologies mostly achieve this optimization by changing the pallet structure and increasing its density. Generally, the density of molded pallets is around 800 kg / m³. 3 However, excessively high density will increase the cost of raw materials and transportation.

[0004] In view of this, there is an urgent need to develop a molded tray with low density and high strength, which is of great significance for achieving cost reduction and efficiency improvement. Summary of the Invention

[0005] Therefore, the technical problem to be solved by this application is to overcome the defects of the prior art, such as the high density of high-strength molded pallets increasing the cost of raw materials and transportation, thereby providing a molded pallet and its preparation method.

[0006] Therefore, this application provides the following technical solution.

[0007] According to one aspect of this application, a molded pallet is provided, the raw materials comprising wood shavings and an adhesive, wherein the wood shavings have a thickness of 0.4-0.6 mm, a length of 30-50 mm, and a width of 5-15 mm, and poplar shavings comprise 60%-80% of the weight of the oven-dried wood shavings; as an example, the proportion of poplar shavings is 60%, 63%, 65%, 68%, 70%, 75%, 80%, or within any range of the above values.

[0008] The adhesive is a polyurethane adhesive, comprising an aromatic isocyanate and a polyol composition. The polyol composition has a hydroxyl value of 400-415 mgKOH / g, a molecular weight of 400-550, and a functionality of 3.2-4. The adhesive has an isocyanate index of 1.2. <R<1.5。

[0009] As an example, the hydroxyl value of the polyol composition is 400 mg KOH / g, 402 mg KOH / g, 405 mg KOH / g, 408 mg KOH / g, 410 mg KOH / g, 413 mg KOH / g, 415 mg KOH / g, or within any of the above values; the molecular weight can be 400, 420, 440, 450, 460, 480, 500, 550, or within any of the above values; the functionality is 3.2, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, or within any of the above values; and the isocyanate index R of the adhesive is 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, or within any of the above values.

[0010] In some alternative embodiments, the amount of adhesive used is 4.5% to 9% of the weight of oven-dried wood shavings. As an example, the amount of adhesive used is 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9% of the weight of wood shavings, or within any range of the above values.

[0011] This application can control production costs while ensuring the strength performance of the molded tray by limiting the amount of adhesive used. If the amount used is too high, it will increase the cost of raw materials.

[0012] In some optional embodiments, the wood shavings also include 20%-40% mixed hardwood shavings, optionally including at least one of eucalyptus, fir, camphor, and birch;

[0013] And / or, poplar includes at least one of Populus tomentosa, Alnus simonii, and Populus 46.

[0014] In some alternative embodiments, the aromatic isocyanate includes at least one of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, or toluene diisocyanate. Typically, and not exclusively, the polymethylene polyphenyl polyisocyanate is selected from the Wannate series of polyisocyanates from Wanhua Chemical Group Co., Ltd., including any one or a combination of at least two of PM-100, PM-200, PM-400, PM-600, PM-700, CW20, CW30, PM300E, 9131FC, 9132FC, or 9132PLUS.

[0015] In some alternative embodiments, the density of the molded tray is 680-720 kg / m³. 3 The internal bond strength is 1.6-1.85 MPa, and the concentrated load on the board surface is 8000-8600 kg. As an example, the density of the molded pallet is 680 kg / m³. 3 690kg / m 3 700kg / m 3 710kg / m 3 720kg / m 3 The values ​​are 1.6MPa, 1.65MPa, 1.7MPa, 1.75MPa, 1.8MPa, 1.85MPa, or within any of the above values; the concentrated load on the plate is 8000kg, 8100kg, 8200kg, 8300kg, 8400kg, 8500kg, 8600kg, or within any of the above values.

[0016] According to another aspect of this application, a method for preparing a molded pallet is provided, comprising the following steps: mixing wood shavings with an adhesive, molding the mixture, and obtaining the molded pallet.

[0017] In some optional embodiments, the molding pressure is 12-13 MPa, the temperature is 150-170°C, and the time is 140-160 s. As an example, the molding pressure is 12 MPa, 12.3 MPa, 12.5 MPa, 12.8 MPa, 13 MPa, or any range thereof; the molding temperature is 150°C, 153°C, 155°C, 158°C, 160°C, 165°C, 170°C, or any range thereof; and the molding time is 140 s, 143 s, 145 s, 148 s, 150 s, 152 s, 155 s, 157 s, 160 s, or any range thereof. The molding process of this application for molded trays can effectively reduce the hot-pressing cycle and temperature, improving production efficiency while reducing heat consumption, achieving energy saving, emission reduction, and green low-carbon development.

[0018] In some alternative embodiments, the wood shavings are dried to control the moisture content to 14%-16%. As an example, the moisture content is controlled at 14%, 14.2%, 14.5%, 14.8%, 15%, 15.3%, 15.5%, 15.7%, 16%, or within any range of the above values.

[0019] In some alternative implementations, a drum chipper or a ring chipper is used to produce wood shavings;

[0020] And / or, the wood shavings are 0.4-0.6 mm thick, 30-50 mm long, and 5-15 mm wide.

[0021] In some alternative embodiments, the air-dry average density of the wood raw material used to prepare wood shavings is less than 0.5 g / cm³. 3 By limiting the air-dry density of the timber raw materials, it is possible to avoid the final pallet density being too high, which would otherwise result in an excessively high air-dry density.

[0022] In some alternative embodiments, the process of mixing the wood shavings with the adhesive employs aerosol atomization.

[0023] Specifically, the preparation method of the molded tray includes the following processes: shavings preparation, shavings drying, shavings gluing, and molding. The preparation method of this invention can generally follow the conventional process for molded trays, but requires adjustment of the shavings preparation equipment. A ring-type shaving machine replaces the hammer mill for shavings preparation.

[0024] In one specific embodiment, the molding tray manufacturing process includes:

[0025] (1) Preparation of wood shavings, the specific process requirements are as follows:

[0026] The equipment for preparing wood chips includes a drum chipper and a ring flaker. The operating parameters of each equipment are adjusted according to the quality requirements of the wood chips. The required form of the prepared wood chips is that the thickness is 0.4 - 0.6 mm, the length is 30 - 50 mm, and the width is 5 - 15 mm.

[0027] (2) Wood chip drying, the specific process requirements are as follows:

[0028] The wood chips are dried using a single - channel dryer, and the moisture content after drying is controlled at 14% - 16%.

[0029] (3) Wood chip sizing, the specific process requirements are as follows:

[0030] For wood chip sizing, pneumatic atomization sizing is required. The aromatic isocyanate and polyol composition in the adhesive system are applied separately. First, the aromatic isocyanate is applied, and then the polyol composition is applied.

[0031] (4) Compression molding, the specific process requirements are as follows:

[0032] The compression molding is carried out using a molding press to form a nine - foot pallet. The compression molding process is that the hot - pressing pressure is 12 - 13 MPa, the hot - pressing temperature is 150 - 170 °C, and the hot - pressing time is 140 - 160 s.

[0033] The technical solution of this application has the following advantages:

[0034] The compression - molded pallet provided by this application uses wood chips and an adhesive as raw materials. The thickness of the wood chips is 0.4 - 0.6 mm, the length is 30 - 50 mm, and the width is 5 - 15 mm. Based on the weight of the absolutely dry wood chips, the proportion of poplar wood chips is 60% - 80%; the adhesive includes aromatic isocyanate and polyol composition. The hydroxyl value of the polyol composition is 400 - 415 mgKOH / g, the molecular weight is 400 - 550, and the functionality is 3.2 - 4. The isocyanate index of the adhesive is 1.2 < R < 1.5. By selecting and proportioning the wood raw materials, optimizing the form of the wood chips, and choosing a special adhesive system, this application reduces the density of the pallet while increasing the strength of the pallet, can significantly reduce the raw material and production costs, and effectively reduces the transportation cost. In addition, the compression - molded pallet is a formaldehyde - free compression - molded pallet, and the product is more environmentally friendly and healthy. Description of the Drawings

[0035] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0036] Figure 1 This is a photograph of the molded tray provided in Embodiment 1 of this application. Detailed Implementation

[0037] The following embodiments are provided to better understand this application and are not limited to the preferred embodiments described herein. They do not constitute a limitation on the content and scope of protection of this application. Any product that is the same as or similar to this application, derived by anyone under the guidance of this application or by combining features of this application with other prior art, falls within the scope of protection of this application.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The term "and / or" may be used herein to include any and all combinations of one or more of the associated listed items.

[0039] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0040] The following describes some of the raw materials used in the examples or comparative examples:

[0041] Aromatic isocyanate: WANNATE 9131FC, functionality approximately 2.4, isocyanate (-NCO) content 27.5-30.0%, viscosity at 25℃ 350-700cp, Wanhua Chemical Group Co., Ltd.

[0042] Polyether polyol I: WANOL R2304, hydroxyl value 415±10mg KOH / g, molecular weight 405, functionality 3, Wanhua Chemical Group Co., Ltd.

[0043] Polyether polyol II: WANOL 8240, hydroxyl value 400±20mg KOH / g, molecular weight 630, functionality 4.5, Wanhua Chemical Group Co., Ltd.

[0044] Polyether polyol III: WANOL R4110H, hydroxyl value 480±15mg KOH / g, molecular weight 470, functionality 4, Wanhua Chemical Group Co., Ltd.

[0045] The main experimental instruments used in the test in this embodiment are:

[0046] Pallet mechanical testing machine, PN CT50KE, Hangzhou Pinxiang Technology Co., Ltd., is mainly used to test pallet forklift performance and concentrated load on the pallet surface;

[0047] The A17000H universal mechanical testing machine, manufactured by Dongguan High-speed Railway Testing Instruments Co., Ltd., is mainly used to test the internal bonding strength of the tray, the bending strength of the reinforcing ribs, and the compressive strength of the support legs.

[0048] During production, the overall production process follows the conventional process of a molded pallet production line. The main difference lies in controlling the shape of the wood shavings through a shavings preparation device.

[0049] Example 1

[0050] This embodiment provides a molded tray, and the process is as follows:

[0051] Design density: 700 kg / m³ 3 ,

[0052] The raw material ratio for wood shavings is: poplar: miscellaneous wood = 70:30 (wherein, the poplar is young poplar, with an air-dry average density of 0.347 g / cm³). 3 The wood is approximately 0.45 g / cm³; it is a mixture of eucalyptus, fir, camphor, and birch, with an average air-dry density of 0.45 g / cm³. 3 about),

[0053] Drying moisture content: 15±0.5%

[0054] Particleboard dimensions: thickness 0.4-0.6mm, length 30-50mm, width 5-15mm;

[0055] Based on the weight of oven-dried wood shavings, the amount of aromatic isocyanate 9131FC added is 4 wt% of the weight of wood shavings, and the polyol composition is a mixture of WANOL R2304 and WANOL 8240, with the amount of polyol composition being 2.7 wt% of the weight of wood shavings (the mass ratio of the two polyether polyols is 2:1, and the R value is approximately 1.40).

[0056] The preparation process includes:

[0057] (1) Preparation of wood shavings:

[0058] The equipment for preparing wood shavings includes a drum chipper and a ring chipper. The drum chipper first produces shavings, followed by the ring chipper. The operating parameters of each piece of equipment are adjusted according to the required shaving quality. The desired shaving shape is 0.4-0.6 mm thick, 30-50 mm long, and 5-15 mm wide.

[0059] (2) Drying wood shavings:

[0060] The wood shavings were dried using a single-channel dryer, and the moisture content after drying was controlled at 15±0.5%.

[0061] (3) Applying adhesive to wood shavings:

[0062] For wood shavings, aerosol application is required. The isocyanate component and polyol composition in the adhesive system should be applied separately, with the isocyanate applied first, followed by the polyol composition. The adhesive application temperature is 50℃.

[0063] (4) Compression molding:

[0064] Compression molding uses a compression molding machine to mold trays (as shown in the picture). Figure 1 As shown, the dimensions are 1100mm in length and width, and 12mm in thickness. The molding process is as follows: molding pressure is 12MPa, molding temperature is 160℃, and molding time is 150s.

[0065] Example 2

[0066] This embodiment provides a molded tray, which differs from Example 1 in the composition and amount of the adhesive: based on the weight of oven-dried wood shavings, the amount of aromatic isocyanate 9131FC added is 4.5 wt% of the weight of wood shavings, the polyol composition is a mixture of WANOL R2304 and WANOL 8240, and the amount of polyol composition used is 3.6 wt% of the weight of wood shavings (the mass ratio of the two polyether polyols is 1:1, and the R value is approximately 1.31). Other processes are the same as those in Example 1.

[0067] Example 3

[0068] This embodiment provides a molded tray, which differs from Example 1 in the composition and amount of the adhesive: based on the weight of oven-dried wood shavings, the amount of aromatic isocyanate 9131FC added is 4 wt% of the weight of the wood shavings, the polyol composition is a mixture of WANOL R2304 and WANOL 8240, and the amount of the polyol composition is 3.3 wt% of the weight of the wood shavings (the mass ratio of the two polyether polyols is 2:1, and the R value is approximately 1.26). Other processes are the same as those in Example 1.

[0069] Example 4

[0070] This embodiment provides a molded tray, which differs from Embodiment 1 in that the composition of the wood shavings is different: the ratio of poplar to mixed wood is 60:40, and the other processes are the same as those in Embodiment 1.

[0071] Example 5

[0072] This embodiment provides a molded tray, which differs from Embodiment 1 in that the composition of the wood shavings is different: the ratio of poplar to mixed wood is 80:20, and the other processes are the same as those in Embodiment 1.

[0073] Example 6

[0074] This embodiment provides a molded tray, which differs from Embodiment 1 in that the molding process parameters are different: the molding pressure is 13MPa, the molding temperature is 150℃, the molding time is 160s, and other processes are the same as those in Embodiment 1.

[0075] Example 7

[0076] This embodiment provides a molded tray, which differs from Embodiment 1 in that the molding process parameters are different: the molding pressure is 12.5 MPa, the molding temperature is 170°C, the molding time is 140 s, and other processes are the same as those in Embodiment 1.

[0077] Example 8

[0078] This embodiment provides a molded tray, which differs from Example 1 in the composition and amount of the adhesive: based on the weight of oven-dried wood shavings, the amount of aromatic isocyanate 9131FC added is 2.8 wt% of the weight of wood shavings, the polyol composition is a mixture of WANOL R2304 and WANOL 8240, and the amount of polyol composition is 2.2 wt% of the weight of wood shavings (the mass ratio of the two polyether polyols is 1:1, and the R value is approximately 1.33). Other processes are the same as those in Example 1.

[0079] Comparative Example 1

[0080] This comparative example provides a molded tray, which differs from Example 1 in that the composition of the wood shavings is different. The raw material does not contain poplar wood, that is, only mixed wood is used. Other processes are the same as those in Example 1.

[0081] Comparative Example 2

[0082] This comparative example provides a molded tray, which differs from Example 5 in that the wood shavings are composed differently. The raw material does not contain mixed wood, that is, only poplar wood is used. Other processes are the same as those in Example 5.

[0083] Comparative Example 3

[0084] This comparative example provides a molded tray, which differs from Example 1 in that the wood shavings are of different shapes. The wood shavings are 1.5-3mm thick, 20-60mm long, and 2-6mm wide. Other processes are the same as those in Example 1.

[0085] Comparative Example 4

[0086] This comparative example provides a molded tray, which differs from Example 1 in the amount and type of adhesive added: the comparative example is based on the weight of oven-dried wood shavings, the amount of aromatic isocyanate 9131FC added is 6.7 wt% of the weight of wood shavings, no polyol composition is added, and other processes are the same as those in Example 1.

[0087] Comparative Example 5

[0088] This comparative example provides a molded tray, which differs from Example 1 in the amount and type of adhesive added: the comparative example is based on the weight of oven-dried wood shavings, the amount of aromatic isocyanate 9131FC added is 3.9 wt% of the weight of wood shavings, the amount of polyol WANOL R2304 added is 2.8 wt% of the weight of wood shavings (R value = approximately 1.43), and other processes are the same as those in Example 1.

[0089] Comparative Example 6

[0090] This comparative example provides a molded tray, which differs from Example 1 in the amount and type of adhesive added: the comparative example is based on the weight of oven-dried wood shavings, the amount of aromatic isocyanate 9131FC added is 3.9 wt% of the weight of wood shavings, the amount of polyol WANOL 8240 added is 2.92 wt% of the weight of wood shavings (R value = 1.43), and other processes are the same as those in Example 1.

[0091] Comparative Example 7

[0092] This comparative example provides a molded tray, which differs from Example 1 in the amount and type of adhesive added: the comparative example is based on the weight of oven-dried wood shavings, the amount of aromatic isocyanate 9131FC added is 3.9 wt% of the weight of wood shavings, the amount of polyol WANOL R4110H added is 2.43 wt% of the weight of wood shavings (R value = approximately 1.43), and other processes are the same as those in Example 1.

[0093] Comparative Example 8

[0094] This comparative example provides a molded pallet. Compared with Example 1, the difference lies in the addition amount and types of adhesives: Based on the weight of absolutely dry wood shavings, the addition amount of aromatic isocyanate 9131FC is 4wt% of the weight of wood shavings. The polyol composition is a mixture of WANOL R2304 and WANOL 8240, and the dosage of the polyol composition is 2.25wt% of the weight of wood shavings (the mass ratio of the two polyether polyols is 2:1, and the R value is about 1.85). Other processes adopt the same preparation process as in Example 1.

[0095] Comparative Example 9

[0096] This comparative example provides a molded pallet. Compared with Example 1, the difference lies in the addition amount and types of adhesives: Based on the weight of absolutely dry wood shavings, the addition amount of aromatic isocyanate 9131FC is 4wt% of the weight of wood shavings. The polyol composition is a mixture of WANOL R2304 and WANOL 8240, and the dosage of the polyol composition is 4.2wt% of the weight of wood shavings (the mass ratio of the two polyether polyols is 2:1, and the R value is about 0.99). Other processes adopt the same preparation process as in Example 1.

[0097] Test Example

[0098] The molded pallets provided by each example and comparative example were tested in accordance with GB / T 412312021 "General Technical Conditions for Bamboo and Wood Shaving Molded Pallets". The test results are shown in the following table:

[0099] Table 1

[0100]

[0101]

[0102] The results of Examples 1 - 8 show that by controlling the poplar content in the wood shaving raw material to be 60 - 80%, the thickness of the shavings to be 0.4 - 0.6 mm, the length to be 30 - 50 mm, and the width to be 5 - 15 mm; and by using an adhesive system prepared from aromatic isocyanate and polyol composition (the hydroxyl value of the polyol composition is 400 - 415 mgKOH / g, the molecular weight is 400 - 550, the functionality is 3.2 - 4, and the isocyanate index 1.2 < R < 1.5), a low-density and high-strength molded pallet can be prepared, which can reduce the density while meeting the mechanical property requirements, reduce the production cost and transportation cost, and better meet the needs of customers and the market.

[0103] The comparison results between Example 1 and Comparative Example 1, and between Example 5 and Comparative Example 2 show that the production of low-density and high-strength molded pallets requires specific compositions of wood raw materials. Specific raw materials must be selected to manufacture low-density and high-strength molded pallets. Although the molded pallets provided by Comparative Examples 1 and 2 have low density, their strength performance is also significantly reduced, and they simply cannot meet the usage requirements. The results of Example 1 and Comparative Example 3 show that the production of low-density and high-strength molded pallets requires specific particle shapes. If the particle shapes are not within the scope defined in this application, it will also lead to a significant reduction in mechanical properties, and low-density and high-strength molded pallets cannot be obtained. The results of Example 1 and Comparative Examples 4-9 show that a specific adhesive system is required to prepare low-density and high-strength molded pallets, which is prepared from aromatic isocyanate and polyol composition. The hydroxyl value of the polyol composition is 400-415 mgKOH / g, the molecular weight is 400-550, the functionality is 3.2-4, and the isocyanate index is 1.2 < R < 1.5. When using isocyanate alone and adding a single polyol within a suitable functionality range, low-density and high-strength molded pallets cannot be prepared if the isocyanate index is too high or too low.

[0104] Obviously, the above examples are merely illustrations for clear explanation and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation manners here. The obvious changes or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A molded tray, characterized in that, The raw materials include wood shavings and adhesives. The wood shavings are 0.4-0.6 mm thick, 30-50 mm long, and 5-15 mm wide. Based on the weight of the oven-dried wood shavings, poplar wood shavings account for 60%-80%. The adhesive comprises an aromatic isocyanate and a polyol composition, wherein the polyol composition has a hydroxyl value of 400-415 mg KOH / g, a molecular weight of 400-550, and a functionality of 3.2-4, and the adhesive has an isocyanate index of 1.

2. <R<1.5。 2. The molded tray according to claim 1, characterized in that, Based on the weight of oven-dried wood shavings, the amount of adhesive used is 4.5%-9% of the weight of the wood shavings.

3. The molded tray according to claim 1, characterized in that, The wood shavings also include 20%-40% mixed hardwood shavings, optionally including at least one of eucalyptus, fir, camphor, and birch; And / or, poplar includes at least one of Populus tomentosa, Alnus simonii, and Populus 46.

4. The molded tray according to claim 1, characterized in that, The aromatic isocyanate includes at least one of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, or toluene diisocyanate.

5. The molded tray according to any one of claims 1-4, characterized in that, The density of the molded tray is 680-720 kg / m³. 3 The internal bond strength is 1.6-1.85MPa, and the concentrated load on the plate surface is 8000-8600kg.

6. A method for preparing a molded tray according to any one of claims 1-5, characterized in that, The process includes the following steps: mixing wood shavings with adhesive, molding them into shape, and obtaining the molded tray.

7. The method for preparing a molded tray according to claim 6, characterized in that, The compression molding pressure is 12-13 MPa, the temperature is 150-170℃, and the time is 140-160 s.

8. The method for preparing a molded tray according to claim 6, characterized in that, The wood shavings are dried to control the moisture content to 14%-16%.

9. The method for preparing a molded tray according to claim 6, characterized in that, Wood shavings were prepared using a drum chipper and a ring chipper. And / or, the air-dry average density of the wood raw material used to prepare wood shavings is less than 0.5 g / cm³. 3 ; And / or, the wood shavings are 0.4-0.6 mm thick, 30-50 mm long, and 5-15 mm wide.

10. A method for preparing a molded tray according to any one of claims 6-9, characterized in that, The process of mixing the wood shavings with the adhesive is carried out using air atomization.

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