AU2009262355A1

AU2009262355A1 - A plastics product and a method and apparatus for the manufacture thereof

Info

Publication number: AU2009262355A1
Application number: AU2009262355A
Authority: AU
Inventors: Ian Janetzki
Original assignee: Huhtamaki Australia Pty Ltd
Current assignee: Huhtamaki Australia Pty Ltd
Priority date: 2008-06-26
Filing date: 2009-06-26
Publication date: 2009-12-30
Also published as: NZ590145A; WO2009155653A1

Description

WO 2009/155653 PCT/AU2009/000814 1 A PLASTICS PRODUCT AND A METHOD AND APPARATUS FOR THE MANUFACTURETHEREOF FIELD OF INVENTION The present invention is directed to products and/or components for 5 products in general comprising at least a portion of plastic material, as wells as a method of and apparatus for the manufacture of plastic products. The present invention is applicable to a method, apparatus for manufacture and a product and/or components of (or at least having a portion thereof) made of any type of plastic material. 10 In one form, the invention relates to any plastics product which has relatively thin portions of the product. For example, the invention relates to containers for foodstuffs, such as ice-cream, fluids, margarine and so on, and one particular aspect the present invention is suitably applicable to containers including a base having a top opening and a lid secured on the base and 15 extending across the top opening. It will be convenient to hereinafter describe the invention in relation to foodstuff containers, however it should be appreciated that the present invention is not limited to that use only. BACKGROUND ART 20 Throughout this specification the use of the word "inventor" in singular form may be taken as reference to one .(singular) inventor or more than one (plural) inventor of the present invention. The inventor has identified that there is an ongoing need in the manufacture of plastic products to use as little plastic feedstock as possible. In 25 other words, if a plastics product can be manufactured to a satisfactory specification with minimal plastic feedstock, this will result in a lower cost of manufacture of the product. The inventor has also identified that there is a problem in the manufacture of plastics based products. Plastics based products are usually shaped using a 30 mould. Moulds, however, have a problem called 'flow ratio'. The flow ratio relates to the thickness of the plastics material and the length of travel that the plastics material is required to travel in the mould during the manufacture of the plastics based product. One of the limiting factors of flow ratio is the cooling. of WO 2009/155653 PCT/AU2009/000814 2 the plastics material as it travels throughout a mould used to shape the product being manufactured. The mould and the plastics material are often at different temperatures. The mould is often at a cooler temperature in order to cool and harden the plastic material of the product being manufactured. Thus, as the 5 plastics material flows into the mould, the plastics material begins to cool through thermal interaction with the mould, If the mould was also heated in order to obviate this cooling problem, then the mould itself will need to be cooled once the plastics material had permeated the mould cavity to enable the plastic to harden, and so the mould can be opened to release the manufactured product. 10 The inventor has identified that in the prior art, channels can be formed in the mould in order to enhance the flow of molten plastics material to permeate a mould. Figure 1 provides an illustration of this approach. For example, if a square shaped product 100 was to be manufactured in a mould, molten plastics material can be injected at point 101 into a mould (not shown), the mould having 15 a cavity of the shape of the square shaped product to be manufactured. The injected plastics material would then permeate into regions 103 as well as down channels 102,. The channels 102 are designed to carry the injected material at a rate so as to deliver the material to the end of the channel at approximately the same time as the material in region 103 reaches the perimeter of the square 20 shaped product. In this way, the injected material reaches all of the perimeter of the square shaped product at approximately the same time. Figure 2 illustrate a cross section of Figure 1, in which the mould has two halves 201 and 202, which are design to separate to release the moulded product. Channel 102 indicates a larger area where plastics material can travel 25 more freely and 203 represents the cavity In which portions of the disc 103 are cast. The inventor has identified that Figure 3 represents a further prior art plastics material product 300 (in cross section) which has also been cast in a similar manner as explained above in Figure 1 and 2 using channels in the mould 30 to improve the flow ratio. The product of Figure 3 has a corrugation 301, which results from the channel provided in the mould (102 in Figure 2). .The product 300 nonetheless still has a minimum thickness 303, which provides some rigidity to the product 300.

WO 2009/155653 PCT/AU2009/000814 3 The inventor has furthermore identified that if the wall thickness 303 is reduced too far, the rigidity of the product itself, as well as (potentially) the mechanical strength of the product, will be compromised due to the fact that the product becomes too weak as the wall thickness is reduced or thinned. The 5 product may even suffer mechanically due to the reduced wall thickness resulting in a break or tear in the product at or around the thinned areas. The discussion throughout this specification comes about due to the realisation of the inventor and/or the identification of certain related art problems by the inventor and, moreover, any discussion of documents, devices, acts or 10 knowledge in this specification is included to explain the context of the invention. It should not be taken as an admission that any of the material forms a part of the prior art base or the common general knowledge in the relevant art in Australia or elsewhere on or before the priority date of the disclosure and claims herein. SUMMARY OF INVENTION 15 An object of the present invention is to an improved plastics product, it's apparatus for and method of manufacture. It is an object of the embodiments described herein to overcome or alleviate at least one of the above noted drawbacks of related art systems or to at least provide a useful alternative to related art systems. 20 In a first aspect of embodiments described herein there is provided a method of manufacturing a component and/or a component adapted to form at least a part of a product, the component being comprised, at least in part, of a mouldable material, comprising a first layer of the mouldable material, the first layer having at least two thicknesses, a first thickness and a second thickness, 25 the second thickness being substantially a reduced area of thickness, wherein the first thickness and second thickness are determined in accordance with flow ratio. Preferably, the component comprises a second layer coupled to the first layer and being adapted to provide selected mechanical properties to the component. 30 In another aspect of embodiments described herein there is provided a method of manufacturing a component, the component being adapted to form at least a part of a product, the component being comprised, at least in part, of a mouldable material, the method comprising determining a flow ratio applicable to WO 2009/155653 PCT/AU2009/000814 4 dimensions of the component, providing a mould in accordance with the dimensions and forming a first layer of the mouldable material, the first layer being formed with areas of reduced thickness. Other aspects and preferred forms are disclosed in the specification and/or 5 defined in the appended claims, forming a part of the description of the invention. Throughout this specification, 'plastics material' refers to petroleum based material, such as plastic and/or plant based materials, such as starch, PLA. In essence, embodiments of the present invention stem from the realization that channels may be used in mould to enhance flow ratio and/or 10 product/components may be provided which have relatively reduced thickness due to the improved flow ratio. Furthermore, an additional layer (such as a label of food barrier) may be provided. to enhance product properties, such as mechanical strength. Advantages provided by the present invention comprise the following: 15 * Reduced plastic material usage in the manufacture~ of products/components e Enhanced plastics flow in mould e improved flow ratios * enables alternative materials to be used in the manufacture of 20 products/components due to enhanced flow ratio e improved tool and/or component design to provide improved flow ratio e improved mechanical strength of product/component Further scope of applicability of embodiments of the present invention will become apparent from the detailed description given hereinafter. However, it 25 should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since'various changes and modifications within the spirit and scope of the. disclosure herein will become apparent to those skilled in the art from this detailed description. 30 BRIEF DESCRIPTION OF THE DRAWINGS Further disclosure, objects, advantages and aspects of preferred and other embodiments of the present application may be better understood by those WO 2009/155653 PCT/AU2009/000814 5 skilled in the relevant art by reference to the following description of embodiments taken in conjunction with the accompanying drawings, which are given by way of illustration only, and thus are not limitative of the disclosure herein, and in which: Figure 1 Illustrates a prior art mould adapted to mould a plastics product; 5 Figure 2 illustrates a cross sectional view of a mould as shown in Figure 1; Figure 3 illustrates a prior art plastics product; Figure 4a illustrates a cross sectional view of a portion of a plastics product in accordance with an embodiment of the present invention; Figure 4b illustrates a cross sectional view of a portion of a plastics product 10 in accordance with another embodiment of the present invention; Figure 5 illustrates a cross sectional view of a portion of an alternative plastics product in accordance with an embodiment of the present invention; Figure 6 illustrates a cross sectional view of a portion of a further alternative plastics product in accordance with a further embodiment of the' 15 present invention; Figure 7 illustrates flow ratio; and Figure 8 illustrates a method according to an aspect of invention. DETAILED DESCRIPTION The present invention is directed to products and/or components and / or a 20 portion thereof of products or components in general comprising at least a portion of plastic material, as wells as a method of and apparatus for the manufacture of plastic products. The present invention is applicable to a method, apparatus for manufacture and a product and/or components of (or at least having a portion thereof) made of any type of plastic material. The present invention is applicable 25 to injection moulding products/components and processes. Thus, although the following description is directed to component(s), it should -be appreciated that the present invention is not limited to that use only and is equally applicable to a product and/or a portion of a component or product. In one embodiment, the invention is applicable to relatively thin walled 30 products/components/parts. With reference to Figure 4a, a portion of a component 400 is illustrated in cross section. The component 400 may be adapted to form at least a part of a product. The component 400 is preferably comprised, at least in part, of a mouldable material. Various mouldable materials WO 2009/155653 PCT/AU2009/000814 6 may be used. The component may be comprised of a mouldable material, in any proportion, such as any or any combination of: * Polypropylene e Polyethylene 5 0 Polystyrene * Biopolymer, eg PLA . Any other injection mouldable plastics material Preferably, the component comprises between 1% and 100% mouldable materialss, such as the material disclosed herein. 10 The component 400 has a first layer 401, preferably of the mouldable material, the first layer being formed with areas 402 of reduced thickness relative to other areas of thickness 406. Figure 4b illustrates another embodiment In which the component 400 of Figure 4a has a second layer 404 added to the first layer. Thus, the component 15 400 has a second layer 404 coupled to the first layer 401 by (any) suitable means. Preferably the second layer 404 is coupled to the side of the first layer 401 which has the reduced areas of thickness 402. The coupling of the first 401 and second 404 layers provides enhanced mechanical properties, such as relative mechanical strength and/or enhanced rigidity and/or a preferred attribute 20 (such as an oxygen barrier) to the component 400. Preferably, the second layer 404 is coupled/affixed to the first layer to form a relatively uniform component having first 401 and second layers 404. Figure 5 illustrates a kinematic inversion of Figure 4, in which the component 400, has a first layer 401 having reduced areas of thickness 402, and 25 the second layer 404 is coupled to the surface of layer 401 opposite the reduced areas of thickness 402. Figure 6 illustrates a cross sectional view of a portion of a further alternative plastics product in accordance with the present invention, in which a second layer 404 is attached to one surface of the first layer 401 and a third layer 30 405 is attached to the other surface of the layer 401. In this embodiment, and the other embodiments, the layers 404 and/or 405 may be made of any material deemed suitable for the use of the component.

WO 2009/155653 PCT/AU2009/000814 7 As can be surmised, the first layer 401 has at least two thicknesses. A first thickness 406 and a second thickness 402 (Figure 4a). The second thickness 402 is substantially the reduced areas of thickness.. The relative thicknesses between 402 and 406 are determined by the required flow ratio. The flow ratio is 5 given by: Flow ratio (FR) = Lt .............................. equation 1 Where L is the maximum distance of flow of injectable material in mould, and to is the relative thickness of the moulded product/component 10 Flow ratio (FR) is a term understood by those skilled in the art of injection moulding. Figure 7 illustrates example dimensions for calculation of flow ratio. The product 700 has a injection point 701. The injectable material will travel a distance 'L and the product has a thickness 't'. The ratio of thickness 't' to distance 'L' is important to flow rate, especially in injection moulding. Sufficient 15 time must be provided to enable the injectable material to travel the desired distance 'L in the mould. As an example, with regard to Figure 4a, the first thickness 406 is at least two times the thickness of the reduced area thickness 402. Furthermore, preferably, the second thickness 402 may be reduced in thickness compared to a thickness which is normally used in moulding the 20 mouldable material. The second thickness is preferably less than the first thickness 406. The second thickness maybe relatively thin, but should have a thickness greater than zero mm. Advantageously, the component and/or any layer may comprise any or any combination of: 25 * Plastics based material * biopolymers " Paper e Metal e Foil 30 * Laminates * membranes * A label WO 2009/155653 PCT/AU2009/000814 8 In a preferred embodiment, the component may be moulded to incorporate a label into the product/component. In other embodiments, the component and / or any layer may be manufactured according to the present invention in a manner which provides enhanced mechanical properties, such as relative mechanical 5 strength and/or enhanced rigidity and/or a preferred attribute (such as an oxygen barrier) to the component 400. Furthermore, any layer may include indicia (not shown) on at least one surface. The indicia may take any form, such as advertising or a description of the product and/or its contents, for example. Preferably the indicia are printed onto the surface. 10 As noted above, a product may also be formed according to the present invention. The product may be formed wholly or partly in accordance with the present invention. Equally a mould and/or die (not shown) used to make the component and/or product according to the invention should be made to correspond to manufacture the relatively reduced areas 402'as illustrated in the 15 figures. Apparatus may then apply the second and/or third layers to a first layer made in the mould and/or die. The apparatus, moulds and/or dies may also be suitably programmed to manufacture a component and/or product in accordance with the present invention. The present invention contemplates various products, such as food 20 containers, vessel and/or lids, although the invention may be applicable to any plastics product/component. Figure 8 Illustrates a method of manufacturing a component in accordance with an aspect of invention. Preferably, the component is adapted to form at least a part of a product. The first step is to form 701 a first layer. Preferably, the first 25 layer is a layer 401 as disclosed herein. The second step 702 is to couple the first layer 401 to a second layer 404. A third step 703 is only preferable, and not used in all situations, and serves to couple a third layer to the first and/or second layers. While this invention has been described in connection with specific 30 embodiments thereof, it will be understood that it is capable of further modification(s). This application is intended to cover any variations uses or adaptations of the invention following in general, the principles of the invention and including such departures from the present disclosure as come within known WO 2009/155653 PCT/AU2009/000814 9 or customary practice within the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth. As the present invention may be embodied in several forms without departing from the spirit of the essential characteristics of the invention, it should 5 be understood that the above described embodiments are not to limit the present invention unless otherwise specified, but rather should be construed broadly within the spirit and scope of the invention as defined in the appended claims. The described embodiments are to be considered in all respects as illustrative only and not restrictive. 10 Various modifications and equivalent arrangements are intended to be included within the spirit and scope of the invention and appended claims. Therefore, the specific embodiments are to be understood to be illustrative of the many ways in which the principles of the present invention may be practiced. In the following claims, means-plus-function clauses are intended to cover structures 15 as performing the defined function and not only structural equivalents, but also equivalent structures. For example, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface to secure wooden parts together, in the environment of fastening wooden parts, a nail and a 20 screw are equivalent structures. It should also be noted that where a flowchart is used herein to demonstrate various aspects of the invention, it should not be construed to limit the present invention to any particular logic flow or logic implementation. The described logic may be partitioned into different logic blocks (e.g., programs, 25 modules, functions, or subroutines) without changing the overall results or otherwise departing from the true scope of the invention. Often, logic elements may be added, modified, omitted, performed in a different order, or implemented using different logic constructs (e.g., logic gates, looping primitives, conditional logic, and other logic constructs) without changing the overall results or otherwise 30 departing from the true scope of the invention. Various embodiments of the invention may be embodied in many different forms, including computer program logic for use with a processor (e.g., a microprocessor, microcontroller, digital signal processor, or general purpose WO 2009/155653 PCT/AU2009/000814 10 computer), programmable logic for use with a programmable logic device (e.g., a Field Programmable Gate Array (FPGA) or other PLD), discrete components, integrated circuitry (e.g., an Application Specific Integrated Circuit (ASIC)), or any other means including any combination thereof. In an exemplary embodiment of 5 the present invention, predominantly all of the communication between users and the server is implemented as a set of computer program instructions that is converted into a computer executable form, stored as such in a computer readable medium, and.executed by a microprocessor under the control of an operating system. 10 Computer program logic implementing all or part of the functionality where described herein may be embodied in various forms, including a source code form, a computer executable form, and various intermediate forms (e.g., forms generated by an assembler, compiler, linker, or locator). Source code may include a series of computer program instructions implemented in any of various 15 programming languages (e.g., an object code, an assembly language, or a high level language such as Fortran, C, C++, JAVA, or HTML) for use with various operating systems or operating environments. The source code may define and use various data structures and communication messages. The source code may be in a computer executable form (e.g., via an interpreter), or the source code 20 may be converted (e.g., via a translator, assembler, or compiler) into a computer executable form. The computer program may be fixed in any form (e.g., source code form,, computer executable form, or an intermediate form) either permanently or transitorily in a tangible storage medium, such as a semiconductor memory 25 device (e.g, a RAM, ROM, PROM, EEPROM, or Flash-Programmable RAM), a magnetic memory device (e.g., a diskette or fixed disk), an optical memory device (e.g., a CD-ROM or DVD-ROM), a PC card (e.g., PCMCIA card), or other memory device. The computer program may be fixed in any form in a signal that is transmittable to a computer using any of various communication technologies, 30 including, but in no way limited to, analog technologies, digital technologies, optical technologies, -wireless technologies (e.g., Bluetooth), networking technologies, and inter-networking technologies. The computer program may be distributed in any form as a removable storage medium with accompanying WO 2009/155653 PCT/AU2009/000814 11 printed or electronic documentation (e.g., shrink wrapped software), preloaded with a computer system (e.g., on system ROM or fixed disk), or distributed from a server or electronic bulletin board over the. communication system (e.g., the Internet or World Wide Web). 5 Hardware logic (including programmable logic for use with a. programmable logic device) implementing all or part of the functionality where described herein may be designed using traditional manual methods, or may be designed, captured, simulated, or documented electronically using various tools, such as Computer Aided Design (CAD), a hardware description language (e.g., VHDL or 10 AHDL), or a PLD programming language (e.g., PALASM, ABEL, or CUPL). Programmable logic may be fixed either permanently or transitorily in a tangible storage medium, such as a semiconductor memory device (e.g., a RAM, ROM, PROM, EEPROM, or Flash-Programmable RAM), a magnetic memory device (e.g., a diskette or fixed disk), an optical memory device (e.g., a CD-ROM 15 or DVD-ROM), or other memory device. The programmable logic may be fixed in a signal that is transmittable to a computer using any of various communication technologies, including, but in no way limited to, analog technologies, digital technologies, optical technologies, wireless technologies (e.g., Bluetooth), networking technologies, and internetworking technologies. The programmable 20 logic may be distributed as a removable storage medium with accompanying printed or electronic documentation (e.g., shrink wrapped software), preloaded with a computer system (e.g., on system ROM or fixed disk), or distributed from a server or electronic bulletin board over the communication system (e.g., the Internet or World Wide Web). 25 "Comprises/comprising" when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of. one or more other features, integers, steps, components or groups thereof." Thus, unless the context clearly requires otherwise, throughout the description and the claims, the words 'comprise', 30 'comprising', and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to".

Claims

1. A component adapted to forn at least a part of a product, the component being comprised, at least in part, of a mouldable material, the component 5 comprising: a first layer of the mouldable material, the first layer having at least two thicknesses, a first thickness and a second thickness, the second thickness being substantially a reduced area of thickness, wherein the first thickness and second thickness are determined in accordance with flow 10 ratio.

2. A component as claimed in claim 1, further comprising a second layer coupled to the first layer and being adapted to provide selected mechanical properties to the component. 15

3. A component as claimed in claim 2, wherein the property is mechanical strength.

4. A component as claimed in claim 2 or 3, wherein the second layer is 20 coupled in a manner which provides strength to the first layer.

5. A component as claimed in claim 2, 3 or 4, wherein the second layer provides rigidity to the first layer. 25

6. A component as claimed in any one of claims 2 to 5, wherein the second layer is adapted to include indicia on at least one surface.

7. A component as claimed in claim 6, wherein the indicia is printed onto the surface. 30

8. A component as claimed in any one of claims 1 to 7, wherein the first thickness is at least two times the thickness of the reduced area. WO 2009/155653 PCT/AU2009/000814 13

9. A component as claimed in any one of claims 1 to 8, wherein the second thickness is greater than zero mm.

10. A component as claimed in any one of claims 2 to 9, wherein the second 5 layer is affixed to the first layer to form a laminate of the first and second layers.

11. A component as claimed in any one of claims I to 10, wherein a third layer is coupled to the first and second layers. 10

12. A component as claimed in any one of claims 1 to 11, wherein the component and/or any or each layer comprises at least a portion of any or any combination of: * Plastics based material * Paper 15 * Metal * biopolymers e A label e Foil * Laminates 20 * membranes

13. A component as claimed in any one of claims I to 12, wherein the mouldable material comprises any or any combination of: * Polypropylene 25 * Polyethylene * Polystyrene * -Biopolymer, eg PLA * Any other injection mouldable 30

14. A product comprising at least a portion being a component as claimed in anyone of claims I to 13. WO 2009/155653 PCT/AU2009/000814 14

15. A product as claimed in claim 14, wherein the product is a container, cup, food vessel, etc

16. A mould or die adapted to make the component as claimed in any one of 5 claims I to 13.

17. A mould or die adapted to make the product as claimed in claim 14 or 15.

18. A method of manufacturing a component, the component being adapted to 10 form at least a part of a product, the component being comprised, at least in part, of a mouldable material, the method comprising the steps of; determining a flow ratio applicable to dimensions of the component providing a mould in accordance with the dimensions forming a first layer of the mouldable material, the first layer being formed 15 with areas of reduced thickness.

19. A method as claimed in claim 18, further comprising the step of coupling to the first layer, a second layer adapted to provide a selected property to the component. 20

20. A method as claimed in claim 19, wherein the property is mechanical strength.

21. A method as claimed in claim 18, 19 or 20, wherein the reduced areas of 25 thickness are determined in order to reduce material used in the manufacture of the component.

22. A mould or die adapted to make a component in accordance with the method as claimed in any one of claims 18 to 21. 30

23. An apparatus adapted to mould a component and/or product as herein disclosed. WO 2009/155653 PCT/AU2009/000814 15

24. Apparatus adapted to mould a component and/or product as herein disclosed, said apparatus including: processor means adapted to operate in accordance with a predetermined instruction set, 5 said apparatus, in conjunction with said instruction set, being adapted to perform the method as claimed in any one of claims 18 to 21 in accordance with a selected flow ratio.

25. A method as herein disclosed. 10

26. A component, product, mould, die and / or apparatus as herein disclosed.