Moulding Composition


Updated about 2 years ago

Abstract

In a food processing line, the equipment which is likely to fragment on breakage contains magnetically susceptible particles which are separated from the food by a magnetic separation stage. When the equipment is a starch carrying tray, the moulding mix contains 5-50% of magnetic filler, such as magnetite. Reinforcement with glass fibre and jute fibre modifies the compositions for moulding the trays. Moulding mixes based on polypropylene and thermosetting resins are described. A processing line using starch trays has a conveyor for food items and a conveyor for the starch in which the food items are moulded. Both have magnetic separators.

Information

Application ID 1384/DELNP/2004
Invention Field GENERAL ENGINEERING
Date of Application 2004-05-21
Publication Number 11/2007

Applicants

Name Address Country Nationality
BELL, GLENDA FAY 4 HORSHAM CRESENT, ALFREDION, 3350, VICTORIA, AUSTRALIA Australia Australia

Inventors

Name Address Country Nationality
MAY, DONALD BRUCE 35 HUME STREET, UPWEY, 3158, VICTORIA, AUSTRALIA Australia Australia
MAY, SHARON 35 HUME STREET, UPWEY, 3158, VICTORIA, AUSTRALIA Australia Australia

Specification

Separation of Equipment Fragmens From A Food Processing Line
FIELD OF THE INVENTION
This invention concerns moulding compositions and articles when moulded from the compositions inter alia for the food industrv and a method of removing physical contamination from food.
BACKGROUND OF THE INVENTION
The invention will be described in its application to the food industrv, but those skilled
in the art will appreciate its applicability to other fields such as pharmaceuticals and mining. The food industry already screens its processes for physical contamination. Metallic parts such as nuts or rivets are easy to remove because metal detectors signal their presence. Plastic parts such as mixer blades, or rubber parts such as 0-rings sometimes fail and these may produce fragments ofdifferent sizes. This problem is dealt withinUS 6,113,482 and US 6,177,113. Incorporation of stainless steel particles in the machinery components which are susceptible to breakage ensures that the fragments elect a signal from a metal detector in the conveyor on which ali products must pass. The detectors which routinely screen the product are runed to find specific sizes and are calibrated with l mm diameter test bališ. It is unrealistic to rely on these to detect smaller metal contaminants.
In confectionery making by factory processes, a special problem arises. It is known in to čast jelly confections in cavities pressed into powders such as starch. The starch is laid as a bed in shallovv trays which pass through a low temperature oven. After the trays of jelly confections have passed through the oven they are inverted over a sieve for reuse. The inversion and other tray handling operarions are performed mechanically, and inevitably a percentage of trays break and fragments contaminate the food. The trays are commonly made of plywood, which dries out with repeated passages through the oven, and if the tray shatters the contamination may affect more than one tray of food. Such failures are a problem and much wholesome food must be discarded to ensure that the result of the failure has been eliminated from the food Une and the starch Une. The starch in the starch line is recycled continuously and it is imperative to ensure that contaminants are not recycled at the same time. The aim is therefore to remove contaminants before thev become embedded in food because then they become more difficult to remove.
A change to thermoset plastic trays which are stronger than plywood has not removed the danger but has exchanged one type of contamination for another. Such thermosetting resins are referred to as sheet moulding compositions (SMC).
SUMMARV OF THE INVENTION
A method aspect of the invention provides a method of detection and removal of
contamination due to the failure in use of trays used in the manufacturing process of material intended for human consumption.
The trays upon failure break into fragments releasing chips or particles that contaminate the confections and the starch. The contamination can then be removed by a suitable magnetic field (permanent or electromagnet) and where this is not practicable the contamination can be detected (by a metal detector) and physically removed.
The composition aspect of the invention provides amouldingmix for thetrays described above comprising a moulding polymer which includes a filler that renders the item susceptible to a magnetic field.
Preferably the filler is present in a quantity sufficient to make possible the capture or detection of the fragments of the item in the event of breakage.
Thermosets which are already in use are suitable except to say that the prior art mixes do not contain the magnetic ingredient. The mix may also contain one or more fillers, for example mineral fillers having no magnetisable property. These would also be present in somewhat less propoitions than is found in commercial mixers because the magnetic component acts as a filler also. The magnetic component may be selected from a group of magnetisable metals, their alloys and their oxides. These are described in the literature. The composition content may comprise magnetic filler 5-30%, resin 15-35%, chopped strand fibreglass 15-35%, and other fillers and additives.
Thus enabling the removal of moulding polymer fragments down to very fine dust that is not othervvise possible \vith metal detection equipment.
In addition, by loading the moulding polymer with up to 50% by wt of magnetic filler in the event that by some means a chip of the moulding polymer mixed with magnetic filler is embedded in a solid piece of food, or packaged into a bag prior to sale, sisnificantly smaller pieces can be detected than would othenvise be possible.
The apparatus aspect of the invention provides a tray or carrier for ingredients used inter
alia in the food industry made from a moulding mix as described above.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure l is a simplified block diagram of the fabrication process for forming a moulding from a plastic material containing the magnetic filler.
Figure 2 is a cross section of a fragment of a starch moulding tray.
Figure 3 is a simplified block diagram representing a food processing line that rnay utilise a plastic material containing the magnetic filler.
Figure 4 is a diagrammatic perspective of a confectionery manufacturing process which utilises starch mogul technology.
DETAILED DESCRIPTION WITH RESPECT TO THE DRAWINGS
In Figure l, the liquid polymer resin is compounded with the particulate fillers and moulded between the heated platens of a compression die. The proportions indicated below suit thermosetting resins also and these require curing periods of about 5 minutes at 150°C. A commercial formulation can be modified by the supplier, such as ASTAR S.A., who may substitute a requested filler for a standard filler, eg. magnetisable filler. As a percentage of the composition 10-50% is magnetisable, whereas the remaining ingredients including polymer are from 20-30%. If glass fibre is unsuitable, it is preferable to substitute an organic vegetable fibre.
Starch trays for confectionery making are moulded rom compositions made to the follovving formulation:-
Example l

o
Polyester resin 25%
Chopped strand glass 25%

Magnetic filler 10%
Other fillers and additives 40%
Example 2
Polyester resin 34%
Jute fibres 26%
Magnetic filler (magnetite) 17%
Other fillers and additives 23%
Both tvpes of filler are mixed with the resin. The jute fibres are laid up as a mat 6mm thick and immersed in the resin/filler mix. Excess is drained and the soaked mat is laid in the die cavity with the edges of the mat brought to the die edges. The die is closed and cured for 5 minutes at 150°C. The resulting tray weighs 3.5kg and measures 800 x 400mm.
m a variant, the shedding of fibres as a result of breakage is suppressed by placing on top of the wet mat a layer of woven fabric which has also been soaked in the same polymer/filler mix.
If thermoplastic trays are required, injection moulding is used instead with no reinforcement, only fillers are incorporated into the injected material.
Example 3
Tale filled polypropylene resin 84%
Magnetic filler 16%
Trays moulded from this composition are much less brittle than trays made from thermosetting resin and tend not to chip. Accordingly, the fragments are larger and are
completely collected by an electromagnet.
Wlule strength is improved, shrinkage and distortion are reduced by the addition of a

small quantity of glass fibre.
Example 4
Tale filled pp 74%
Magnetite 16%
Glass fibre 10%
Magnetite is mined, ground and dried similar to tale, calcium carbonate and other minerals used in the plastics industry as fillers. It is available as a very fine powder with a mean particle siže of 20 microns or finer and has a specific gravity range of about 5.0. Other particles may be used which also have a strong attraction to magnets, these include magnetisable metals, their alloys, their oxides and ferrites. The type of magnetic filler used is dependant on the application, consideration of cost and processing considerations.
Refening now to Figure 2, the tray 2 is approximately 800 x 350 x 30mm and is moulded in a compression die and cured beUveen a pair of heated platens (not shovra).
Figure 3 is a generic block diagram representation of a food processing Une, including food processing equipment, having one or more plastic components manufactured firom a plastic material with a magnetic filler as shown in Figure l. A foodstuff and associated carriers is carried by the equipment. During this process, a breakage may occur resulting in the contamination of the foodstuff or carriers in contact with the foodstuff. The foodstuff or carriers in contact \vith the foodstuff is then passed through magnetic separation equipment.
Referring now to Figure 4, in a confectionery factory, the trays 2 are filled with powdered starch 4 and multiple cavities 6 are pressed into the compacted starch. Jelly items 8 are deposited in the cavities in a known manner. After baking, the trays emerge on conveyer 10 and travci to the transfer station 12 vvhere a mechanical tipper inverts the tray and replaces it on conveyor 10. It is at this station 12 that the trays may break. The jelly items and starch fali onto a suitable screen 14 that separates the starch from the jellies. The starch collects onto conveyor 16 any chips of tray material \vhich pass along the

conveyor 16 with the starch reach magnetic separator 17 which removes them.
The jelly items transferred along conveyor 15 are advanced towards gate 18. This has a horizontal slot 20 which allows the jelly items to pass, but if the tray shatters, the fragments are directed to bin 22. Any chips of tray material which pass along the conveyor with the product reach the magnetic separator 24 which removes more of the tray. Any additional chips of tray that may be adhered to the jellies can be detected by a magnetic field (metal detector) 26 and the jelly and contarninaticn physically separated by rejecting the packet containing the offending jelly.
The dumped starch travels to the reuse area via conveyor 28. Contaminating chips are removed by magnet 30.
I have found the advantages of the above embodiment to be:-
1. Reduces customer complaints about unexpected inclusions in the product.
2. Reduces litigious claims in respect of product contamination.
3. Static electricity controls need to be considered for the transfer of dry starch since
finely divided dusts in air present an explosive hazard. By the addition of an
additive to make the trays dissipate static, the risks to plant and personnel are
reduced.
It is to be understood that the word "comprising" as used throughout the specification is to be interpreted in its inclusive form, ie. use of the word "comprising" does not exclude the addition of otlier elements.
It is to be understood that various modifications of and/or additions to the invention can be made without departing from the basic nature of the invention. These modifications and/or additions are therefore considered to fali vvithin the scope of the invention.

I Claim:

1. A method of separating loose fragments following breakage of food processing
plastic equipment (2) in a food processing line, characterized in that the method
comprising the steps of:
a), exposing foodstuff (8) contaminated with loose fragments of food processing plastic equipment (2) to a magnetic separator or magnets (24) and separation of the fragments by magnetic attraction of the loose fragments of the food processing plastic equipment (2) from the foodstuff (8);
b). exposing the foodstuff (8) contaminated with loose fragments of the food processing plastic equipment (2) either packaged or embedded in the foodstuff (8) to a magnetic detector or metal detection equipment (26) and separating by rejecting the foodstuff detected as contaminated foodstuff containing the loose fragments of food processing plastic equipment (2), thereby recovering the foodstuff (8) free of contamination;
c). exposing the foodstuff (8) or dry carrier (4) with contaminating loose
fragments of food processing plastic equipment (2) to a magnetic separator (17) and recovering the dry carrier (4) free of contamination;
wherein, the equipment is made of a plastic moulding composition comprising 5-50% by weight of magnetic oxides and / or ferrites with a particle size of 20 pm or finer and are capable of separation by magnetic separation or magnetic detection, 15-35% of polymer resins and 15-35% by weight of reinforcement.
2. A method as claimed in claim 1, wherein the magnetic oxide and / or ferrite is
magnetite.
3. A method as claimed in claim 1, wherein said magnetic separator (17) is a plate magnet.
4. A method as claimed in claim 1, wherein said magnetic separator (17) is an array of tube magnets.
5. A method as claimed in claim 1, wherein said foodstuff (8) is confectionery and the dry carrier material (4) is starch.
6. A method as claimed in claim 1, wherein the said equipment (2) is a tray for confectionery items.

Documents

Name Date
1384-DELNP-2004-Petition-137-(04-05-2009).pdf 2009-05-04
1384-delnp-2004-form-13-(04-05-2009).pdf 2009-05-04
1384-DELNP-2004-Form-2-(04-05-2009).pdf 2009-05-04
1384-DELNP-2004-Drawings-(04-05-2009).pdf 2009-05-04
1384-DELNP-2004-Correspondence-Others-(04-05-2009).pdf 2009-05-04
1384-DELNP-2004-Abstract-(04-05-2009).pdf 2009-05-04
1384-DELNP-2004-Claims-(04-05-2009).pdf 2009-05-04
1384-DELNP-2004-Correspondence-Others-(05-05-2009).pdf 2009-05-05
1384-DELNP-2004-Drawings-(05-05-2009).pdf 2009-05-05
1384-DELNP-2004-Form-2-(15-05-2009).pdf 2009-05-15
1384-DELNP-2004-Correspondence-Others-(15-05-2009).pdf 2009-05-15
1384-DELNP-2004-Claims-(15-05-2009).pdf 2009-05-15
1384-delnp-2004-pct-304.pdf 2011-08-21
1384-delnp-2004-pct-409.pdf 2011-08-21
1384-delnp-2004-pct-308.pdf 2011-08-21
1384-delnp-2004-pct-408.pdf 2011-08-21
1384-DELNP-2004-Form-1-(15-05-2009).pdf 2009-05-15
1384-delnp-2004-pct-210.pdf 2011-08-21
1384-delnp-2004-form-5.pdf 2011-08-21
1384-delnp-2004-form-3.pdf 2011-08-21
1384-delnp-2004-form-2.pdf 2011-08-21
1384-delnp-2004-form-1.pdf 2011-08-21
1384-delnp-2004-pct-101.pdf 2011-08-21
1384-delnp-2004-drawings.pdf 2011-08-21
1384-delnp-2004-claims.pdf 2011-08-21
1384-delnp-2004-assignment.pdf 2011-08-21
1384-delnp-2004-abstract.pdf 2011-08-21
1384-delnp-2004-correspondence-other.pdf 2011-08-21
INEXRP-1384-DELNP-2004.pdf 2016-06-30
1384-DELNP-2004_EXAMREPORT.pdf 2016-06-30

Orders

Applicant Section Controller Decision Date URL