Bamboo fiber composite board and method of manufacturing the same

Abstract

The present invention provides a bamboo fiber composite board, comprising: an upper substrate layer including bamboo fiber; and a lower substrate layer including bamboo fiber connected to the upper substrate layer, wherein the lower substrate layer is provided with a plurality of airflow guiding holes extending along the thickness direction to guide airflow to the upper substrate layer.

Description

Technical Field

[0001] This invention relates to a bamboo fiber composite board and its manufacturing method. Background Technology

[0002] With increasingly stringent environmental regulations, vehicle manufacturers are seeking natural and environmentally friendly materials to replace traditional fiberglass polyester. Natural fiber composites, such as bamboo fiber composites, are green and renewable materials with good mechanical properties and low cost, and have been widely used in vehicle interior components. Summary of the Invention

[0003] According to one aspect of the present invention, a bamboo fiber composite board is provided, comprising: an upper substrate layer including bamboo fibers; and a lower substrate layer including bamboo fibers connected to the upper substrate layer, wherein the lower substrate layer is provided with a plurality of airflow guiding holes extending in the thickness direction to guide airflow to the upper substrate layer.

[0004] In one embodiment, the diameter of the first airflow guiding through-hole is 10 mm, and the spacing between the guiding through-holes is 150 mm.

[0005] In another embodiment, the thickness of the lower substrate layer is greater than that of the upper substrate layer.

[0006] In another embodiment, the upper substrate layer and the lower substrate layer further include a thermoplastic resin.

[0007] In another embodiment, the upper substrate layer and the lower substrate layer comprise about 40% to 60% bamboo fiber and about 60% to 40% polypropylene resin.

[0008] In another embodiment, the bamboo fiber content in the lower substrate layer is lower than that in the upper substrate layer.

[0009] In another embodiment, it further includes at least one intermediate substrate layer located between the upper substrate layer and the lower substrate layer, the intermediate substrate layer including a plurality of airflow guiding grooves extending in the plane of the intermediate substrate layer, penetrating the thickness of the intermediate substrate layer and communicating with airflow guiding through holes on the lower substrate plate to form an airflow path.

[0010] In another embodiment, the airflow guiding through-holes in the lower substrate layer are substantially circular, and the airflow guiding grooves in the middle substrate layer are elongated grooves arranged parallel to each other, with the airflow guiding through-holes and airflow guiding grooves at least partially overlapping.

[0011] In another embodiment, at least one intermediate substrate layer includes a first intermediate substrate layer adjacent to the lower substrate layer and a second intermediate substrate layer adjacent to the upper substrate layer. The first intermediate substrate layer is provided with a plurality of first airflow guiding grooves, and the second intermediate substrate layer is provided with a plurality of second airflow guiding grooves. The first airflow guiding grooves and the second airflow guiding grooves are in fluid communication.

[0012] In another embodiment, the projections of the first airflow guide groove and the second airflow guide groove on the upper substrate layer are arranged crosswise.

[0013] In another embodiment, the first airflow guide groove is at least partially aligned with the airflow guide through hole.

[0014] In another embodiment, multiple guide holes form multiple rows, and the spacing between the multiple rows is substantially equal to the spacing between the first guide slots.

[0015] In another embodiment, the upper substrate layer, the lower substrate layer, and at least one intermediate substrate layer have substantially the same thickness.

[0016] According to another aspect of the present invention, a method for manufacturing a bamboo fiber composite board is provided, comprising: providing an upper substrate layer; providing a lower substrate layer; forming a plurality of airflow guiding through holes extending in the thickness direction on the lower substrate layer; and providing a heating plate to heat the upper substrate layer and the lower substrate layer such that hot airflow flows through the airflow guiding through holes into the upper substrate layer.

[0017] In one embodiment, the heating plate includes an upper heating plate and a lower heating plate, wherein the temperature of the upper heating plate is lower than the temperature of the lower heating plate.

[0018] In another embodiment, the method further provides at least one intermediate substrate layer, which has a plurality of elongated airflow guiding grooves that are in fluid communication with airflow guiding through holes in the lower substrate layer.

[0019] In another embodiment, at least one intermediate substrate layer includes a first intermediate substrate layer and a second intermediate substrate layer. The first intermediate substrate layer is provided with a plurality of first airflow guiding grooves, and the second intermediate substrate layer is provided with a plurality of second airflow guiding grooves. The projections of the first airflow guiding grooves and the second airflow guiding grooves on the upper substrate layer are arranged in an intersecting manner.

[0020] In another embodiment, the method further includes bonding an upper substrate layer, a lower substrate layer, and at least one intermediate substrate layer together by heating.

[0021] In another embodiment, the method further includes forming an upper substrate layer, a lower substrate layer, and at least one intermediate substrate layer by a needle punching process.

[0022] In another embodiment, the method further includes providing a mold to form the upper substrate layer and the lower substrate layer.

[0023] One or more features and / or advantages of the present invention will become apparent from one or more embodiments described in detail below, taken in conjunction with the accompanying drawings. Attached Figure Description

[0024] Figure 1 An enlarged schematic diagram of an example bamboo fiber is described.

[0025] Figure 2A An exploded perspective view of a bamboo fiber composite board according to one or more embodiments of the present invention is described.

[0026] Figure 2B Described Figure 2A A partially enlarged schematic diagram of the bamboo fiber composite board.

[0027] Figure 3A A schematic diagram is described, showing a mold for forming guide holes on an underlying substrate layer.

[0028] Figure 3B A schematic diagram is described, showing a heating plate for heating an upper substrate and a lower substrate.

[0029] Figure 3C A schematic diagram is shown illustrating the provision of a mold for shaping a substrate board.

[0030] Figure 4 A flowchart describing a method for manufacturing bamboo fiber composite panels according to one or more embodiments of the present invention is provided.

[0031] Figure 5 A comparison graph depicting the heating efficiency of bamboo fiber composite panels according to one or more embodiments of the present invention with that of conventional bamboo fiber composite panels is described.

[0032] Figure 6 An exploded perspective view of a bamboo fiber composite board according to an alternative embodiment of the present invention is described.

[0033] Figure 7 Described Figure 6 Enlarged cross-sectional diagram of the bamboo fiber composite board along line BB.

[0034] Figure 8 A flowchart illustrating a method for manufacturing a bamboo fiber composite board according to an alternative embodiment of the present invention is provided.

[0035] Figure 9 A graph comparing the heating efficiency of bamboo fiber composite panels according to an alternative embodiment of the present invention with that of conventional bamboo fiber composite panels is described. Detailed Implementation

[0036] Specific embodiments of the invention are disclosed herein as needed; however, it should be understood that the disclosed embodiments are merely examples of the invention and may be implemented in various alternative forms. The drawings are not necessarily drawn to scale; some features may be enlarged or reduced to show details of specific components. Therefore, the specific structural and functional details disclosed herein should not be construed as limiting, but are merely representative bases for teaching those skilled in the art to implement the invention in various forms.

[0037] Automotive interior components are typically made of fiberglass and resin composites, such as fiberglass and polypropylene. However, these composites are difficult to degrade and are environmentally unfriendly. With increasing environmental regulations, the industry is researching and developing natural fiber composites to replace fiberglass, such as bamboo fiber. Processing bamboo fiber with resin materials can produce high-strength, low-cost, and environmentally friendly bamboo fiber composites. Bamboo fiber composites can be widely used in vehicle interior components, such as rear window sills and trunk carpets. During processing, the bamboo fiber composites need to be baked to reduce moisture. Please refer to [reference needed]. Figure 1 , Figure 1 An enlarged schematic diagram of bamboo fiber material 100 is shown. Due to the natural properties of bamboo fiber, it has multiple microporous structures 102, which store heat and are detrimental to heat conduction. Furthermore, bamboo fiber is thicker than glass fiber, which has a thickness of approximately 0.012 mm, reaching 0.12 mm. The thermal conductivity of glass fiber is 1.46 W / mK, while that of bamboo fiber is 0.1 W / mK. Therefore, improving the heating method and efficiency of bamboo fiber composites compared to glass fiber composites becomes a challenge.

[0038] refer to Figure 2A and 2B , Figure 2A An exploded perspective view of a bamboo fiber composite board 200 according to one or more embodiments of the present invention is described. Figure 2B Described Figure 2A A partially enlarged schematic diagram of the bamboo fiber composite board 200 is shown. In one or more embodiments, the bamboo fiber composite board 200 includes an upper substrate layer 202 and a lower substrate layer 204 connected to the upper substrate layer 202, wherein the lower substrate layer 204 is provided with a plurality of airflow guiding through holes 206 extending in the thickness direction W to guide airflow to the upper substrate layer 202. In one or more embodiments, the diameter D of the guiding through holes 206 may be about 10 mm, and the spacing between the guiding through holes 206 may be about 150 mm. Of course, the diameter D and the spacing S of the airflow guiding through holes 206 can be adjusted according to the specific application to achieve a balance between the strength and heating efficiency of the composite board. In one or more embodiments, the upper substrate layer 202 and the lower substrate layer 204 of the bamboo fiber composite board 200 also include a thermoplastic resin. In one or more embodiments, the thermoplastic resin includes, for example, but not limited to, polypropylene, polyethylene, etc. In one or more embodiments, the upper substrate layer and the lower substrate layer contain about 40% to 60% bamboo fiber and about 60% to 40% polypropylene resin. To improve heating efficiency, in one or more embodiments, the bamboo fiber content in the lower substrate layer may be lower than that in the upper substrate layer to facilitate heat conduction.

[0039] Further reference Figure 4 And refer to Figure 2A-2B and Figures 3A-3C , Figure 4 A flowchart 700 describing a method for manufacturing bamboo fiber composite panels is provided. Method 700 begins at 702, where an upper substrate layer 202 and a lower substrate layer 204 are provided. In one or more embodiments, bamboo fiber material and thermoplastic resin can be processed into the upper substrate layer 202 and lower substrate layer 204 of the bamboo fiber composite panel 200 via a needle-punching process. At 704, method 700 forms a plurality of airflow guiding through-holes 206 on the lower substrate layer 204. The airflow guiding through-hole forming can be performed in any process. For example, refer to… Figure 3A The airflow-guided through-hole forming can be performed in a die or a stamping machine 300. The stamping machine 300 includes an upper stamping die 302 and a lower die 304. The upper die 302 has a plurality of protrusions 306 for forming airflow-guided through-holes. Although the protrusions 306 in the figure are cylindrical to form cylindrical through-holes, it should be understood that the protrusions 306 can be any suitable shape, such as a truncated cone to form through-holes with a truncated conical shape.

[0040] At point 706, method 700 heats the upper substrate layer 202 and the lower substrate layer 204 using a heating device 400. In one or more embodiments, the heating device 400 includes an upper heating plate 402 and a lower heating plate 404. In one or more embodiments, to save energy, the temperature of the lower heating plate 404 can be higher than that of the upper heating plate 402. Because the lower substrate layer 204 has multiple airflow guiding holes 206, when heating the upper substrate layer 202 and the lower substrate layer 204, hot air flows from the lower substrate layer 204 to the upper substrate layer 202 through the multiple airflow guiding holes 206, increasing heat conduction.

[0041] In one or more embodiments, the upper substrate layer 202 and the lower substrate layer 204 are joined together by the melting of a thermoplastic resin, such as but not limited to polypropylene, during heating, because the substrate layer contains a thermoplastic resin. That is, at 706, method 700 includes joining the upper substrate layer 202 and the lower substrate layer 204.

[0042] Next, at 708, method 700 provides a die system 500 for molding the upper substrate layer 202 and the lower substrate layer 204. The die system 500 includes an upper die 502 and a lower die 504 to press the bamboo fiber composite board 200 into any desired shape.

[0043] refer to Figure 5 , Figure 5A comparison graph showing the heating efficiency of a bamboo fiber composite board 200 according to one or more embodiments of the present invention and a conventional single-layer bamboo fiber composite board is displayed. The conventional single-layer bamboo fiber composite board has a density of 1700 gsm (grams per square meter). For example, in one embodiment of the present invention, the bamboo fiber composite board 200 has an upper substrate layer 202 and a lower substrate layer 204. Each layer has a density of approximately 850 gsm, and the density of the bamboo fiber composite board is approximately 1700 gsm. The diameter D of the airflow guiding holes 206 on the lower substrate layer is approximately 10 mm, and the spacing between the airflow guiding holes 206 is 150 mm. When heated to 200°C, the single-layer bamboo fiber composite board requires approximately 160 seconds of heating time, while the bamboo fiber composite board of the present invention requires approximately 110 seconds. The bamboo fiber composite board 200 provided by the present invention can significantly shorten the heat processing time, thereby improving manufacturing efficiency.

[0044] refer to Figure 6 , Figure 6 An exploded perspective view of a bamboo fiber composite board 600 according to an alternative embodiment of the present invention is described. In one or more embodiments, the bamboo fiber composite board 600 includes an upper substrate layer 602, a lower substrate layer 604, and at least one intermediate substrate layer 606 located between the upper substrate layer 602 and the lower substrate layer. In one or more embodiments, the lower substrate layer 602 is provided with a plurality of airflow guiding through holes 608 extending in the thickness direction W to guide airflow to the upper substrate layer 602. Further, the intermediate substrate layer 606 includes a plurality of airflow guiding grooves 610, and the airflow guiding grooves 610 communicate with the airflow guiding through holes 608 on the lower substrate layer 602 to form an airflow path. In one or more embodiments, the airflow guiding through holes 608 are substantially circular, and the airflow guiding grooves 610 are elongated grooves arranged parallel to each other. Further, the airflow guiding through holes 608 and the airflow guiding grooves 610 at least partially overlap to form an airflow path.

[0045] In one or more embodiments, at least one intermediate substrate layer 606 includes a first intermediate substrate layer 606a adjacent to a lower substrate layer 604 and a second intermediate substrate layer 606b adjacent to an upper substrate layer 602. The first intermediate substrate layer 606a has a plurality of first airflow guiding grooves 610a, and the second intermediate substrate layer 606b has a plurality of second airflow guiding grooves 610b, with the first airflow guiding grooves 610a and the second airflow guiding grooves 610b in fluid communication.

[0046] refer to Figure 7 and combined Figure 6 , Figure 7 Described Figure 6The diagram shows an enlarged cross-section of the bamboo fiber composite board 600 along line BB. In one or more embodiments, the first airflow guiding groove 610a is at least partially aligned with the airflow guiding through-hole 608 to allow hot airflow to be transmitted from the airflow guiding through-hole 608 to the first guiding groove 610a. In the illustrated embodiment, the airflow guiding through-hole 608 is a truncated cone. The area of ​​the truncated cone decreases along the airflow direction to facilitate airflow. It should be understood that the airflow guiding through-hole 608 can have any suitable shape, such as a cylinder. The first airflow guiding groove 610a communicates with the second airflow guiding groove 610b. Further, the plurality of airflow guiding through-holes 608 can form a plurality of rows, the spacing S1 of the plurality of rows being substantially equal to the spacing S2 between the first airflow guiding grooves 610a, so that the first airflow guiding groove 610a is aligned with or communicates with at least one or more airflow guiding through-holes 608 to improve the efficiency of hot air transmission. In one or more embodiments, the first airflow guiding groove 610a and the second airflow guiding groove 610b can be intersecting, i.e., their projections on the upper substrate layer 602 intersect. In this way, after hot air is transferred to the intermediate layer 606 via the airflow guiding through-hole 608, heat conduction can occur over a larger area, and the air is ultimately transferred to the upper substrate layer 602 via the second airflow guiding groove 610b. Furthermore, the interlacing arrangement of the plurality of first airflow guiding grooves 610a on the first intermediate substrate layer 606a and the plurality of second airflow guiding grooves 610b on the second intermediate substrate layer 606b maintains the overall strength of the bamboo fiber composite board 600 while improving heat transfer. Further, since the plurality of first airflow guiding grooves 610a on the first intermediate substrate layer 606a and the plurality of second airflow guiding grooves 610b on the second intermediate substrate layer 606b are interlaced, in one or more embodiments, the spacing S3 between the second airflow guiding grooves 610b does not necessarily have to be equal to the spacing S1 or S2; it can be adjusted according to the specific application. For example, to increase heat transfer efficiency, the spacing S3 can be smaller than the spacings S1 and S2. To enhance the overall strength of the fiber composite board 600, the spacing S3 can be larger than the spacings S1 and S2.

[0047] refer to Figure 8 , Figure 8A flowchart is described for a method 800 of manufacturing a bamboo fiber composite board 600 according to an alternative embodiment of the present invention. It should be understood that method 800 can be performed using a similar through-hole forming system, heating system, and mold system as method 700. In one or more embodiments, at 802, method 800 provides an upper substrate layer 602, a lower substrate layer 604, and at least one intermediate substrate layer 606. In one or more embodiments, bamboo fiber material and thermoplastic resin can be processed into the upper substrate layer 602, lower substrate layer 604, and at least one intermediate substrate layer 606 of the bamboo fiber composite board 600 by a needle punching process. At 804, method 800 forms a plurality of airflow guiding through holes 608 on the lower substrate layer 604 using a mold. Next, at 806, method 800 forms a plurality of airflow guiding grooves 610 on at least one intermediate substrate layer 606 using a mold. Further, at 808, method 800 heats the upper substrate layer 602 and the lower substrate layer 604 using a heating plate. As hot air flows from the lower substrate 604 through multiple airflow guiding holes 608 and multiple airflow guiding grooves 610 to the upper substrate 202, the airflow path is increased, thereby improving heat transfer efficiency. In one or more embodiments, since the substrate layer contains a thermoplastic resin, such as but not limited to polypropylene, the thermoplastic resin melts during heating, connecting the upper substrate layer 602, the lower substrate layer 604, and at least one intermediate substrate layer 606 together. That is, at 808, method 800 includes connecting the upper substrate layer 602, the lower substrate layer 604, and at least one intermediate substrate layer 606.

[0048] Finally, at 810, method 800 provides a mold to mold the upper substrate layer 602, the lower substrate layer 604 and at least one intermediate substrate layer 606 to form the final part.

[0049] refer to Figure 9 , Figure 9 A comparison diagram of the heating efficiency of the bamboo fiber composite board 600 according to the present invention and a conventional single-layer bamboo fiber composite board is shown. The conventional single-layer bamboo fiber composite board has a density of 2600 gsm (grams per square meter). The bamboo fiber composite board 600 has an upper substrate layer 602, a lower substrate layer 604, and at least one intermediate substrate layer 606. Each layer has a density of 650 gsm. The density of the entire bamboo fiber composite board is 2600 gsm. Furthermore, the diameter D of the airflow guiding holes 608 on the lower substrate layer is approximately 10 mm, and the spacing between the airflow guiding holes 608 is approximately 150 mm. When heated to 160°C, the single-layer bamboo fiber composite board requires a heating time of approximately 145 seconds. The bamboo fiber composite board 600 of the present invention requires a heating time of approximately 115 seconds. Therefore, the bamboo fiber composite board 600 provided by the present invention can shorten the heat processing time, thereby improving manufacturing efficiency.

[0050] Although the various substrate layers of the bamboo fiber composite board have approximately equal thicknesses in the above embodiments, the various substrate layers of the bamboo fiber composite board can also have different thicknesses. For example, in one or more embodiments, because airflow guiding holes and airflow guiding grooves are provided on the lower substrate layer and / or the intermediate substrate layer, the thickness of the lower substrate layer and / or the intermediate substrate layer can be greater than the thickness of the upper substrate layer without affecting the thermal efficiency.

[0051] In one or more embodiments, the present invention effectively increases baking efficiency and significantly improves production efficiency by dividing the traditional single-layer bamboo fiber composite board into several layers and providing airflow guiding holes and / or airflow guiding grooves in the lower base layer and / or intermediate substrate layer.

[0052] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A bamboo fiber composite board, comprising: an upper substrate layer comprising bamboo fibers; a lower substrate layer comprising bamboo fibers connected to the upper substrate layer; at least one intermediate substrate layer between the upper substrate layer and the lower substrate layer; wherein a plurality of air flow guide through holes extending in the thickness direction are provided on the lower substrate layer to guide a hot air flow through an air flow circulation path to the upper substrate layer during processing, wherein the intermediate substrate layer comprises a plurality of air flow guide grooves extending in the plane of the intermediate substrate layer, through the thickness of the intermediate substrate layer and in communication with the air flow guide through holes on the lower substrate layer to form the air flow circulation path, wherein the air flow guide through holes of the lower substrate layer are circular, the air flow guide grooves of the intermediate substrate layer are elongated grooves arranged parallel to each other, and the air flow guide through holes and the air flow guide grooves at least partially overlap. 2.The bamboo fiber composite board of claim 1, wherein the air flow guide through holes have a hole diameter of 10 mm, and the air flow guide through holes have a spacing of 150 mm. 3.The bamboo fiber composite board of claim 1, wherein the lower substrate layer has a thickness greater than the upper substrate layer. 4.The bamboo fiber composite board of claim 1, wherein the upper substrate layer and the lower substrate layer further comprise a thermoplastic resin. 5.The bamboo fiber composite board of claim 2, wherein the upper substrate layer and the lower substrate layer comprise 40-60% bamboo fibers and 60-40% polypropylene resin. 6.The bamboo fiber composite board of claim 5, wherein the lower substrate layer has a lower content of bamboo fibers than the upper substrate layer. 7.The bamboo fiber composite board of claim 1, wherein the at least one intermediate substrate layer comprises a first intermediate substrate layer adjacent to the lower substrate layer and a second intermediate substrate layer adjacent to the upper substrate layer, the first intermediate substrate layer is provided with a plurality of first air flow guide grooves, the second intermediate substrate layer is provided with a plurality of second air flow guide grooves, and the first air flow guide grooves are in fluid communication with the second air flow guide grooves. 8.The bamboo fiber composite board of claim 7, wherein projections of the first air flow guide grooves and the second air flow guide grooves on the upper substrate layer are arranged in a cross shape. 9.The bamboo fiber composite board of claim 8, wherein the first air flow guide grooves are at least partially aligned with the air flow guide through holes. 10.The bamboo fiber composite board of claim 9, wherein the plurality of guide through holes form a plurality of rows, and the spacing of the plurality of rows is equal to the spacing between the first guide grooves. 11.The bamboo fiber composite board of claim 1, wherein the upper substrate layer, the lower substrate layer, and the at least one intermediate substrate layer have the same thickness. 12.A method of manufacturing a bamboo fiber composite board, comprising: providing an upper substrate layer comprising bamboo fibers; providing a lower substrate layer comprising bamboo fibers; forming a plurality of air flow guide through holes extending in the thickness direction on the lower substrate layer; providing at least one intermediate substrate layer provided with a plurality of elongated air flow guide slots in fluid communication with the air flow guide through holes of the lower substrate layer; heating the upper substrate layer and the lower substrate layer by a heating plate such that a hot air flow is communicated to the upper substrate layer through an air flow circulation path formed by the air flow guide through holes and the air flow guide slots during the processing; wherein the air flow guide through holes of the lower substrate layer are circular, the air flow guide slots of the intermediate substrate layer are elongated slots arranged parallel to each other, and the air flow guide through holes at least partially overlap the air flow guide slots.

13. The manufacturing method of claim 12, wherein the heating plate comprises an upper heating plate and a lower heating plate, and the temperature of the upper heating plate is lower than the temperature of the lower heating plate.

14. The manufacturing method of claim 12, wherein the at least one intermediate substrate layer comprises a first intermediate substrate layer and a second intermediate substrate layer, the first intermediate substrate layer is provided with a plurality of first air flow guide slots, the second intermediate substrate layer is provided with a plurality of second air flow guide slots, and projections of the first air flow guide slots and the second air flow guide slots on the upper substrate layer are arranged in cross.

15. The manufacturing method of claim 12, further comprising connecting the upper substrate layer, the lower substrate layer and the at least one intermediate substrate layer together by the heating.

16. The manufacturing method of claim 12, further comprising forming the upper substrate layer, the lower substrate layer and the at least one intermediate substrate layer by a needle punching process.

17. The manufacturing method of claim 12, further comprising forming the upper substrate layer and the lower substrate layer by a mold.

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