Regulation 3.2 Revised 2/98 AUSTRALIA Patents Act, 1990 COMPLETE INNOVATION SPECIFICATION NAME OF APPLICANT COLLIER, Linda ACTUAL INVENTOR COLLIER, Linda ADDRESS FOR SERVICE Peter Maxwell and Associates Level 6 60 Pitt Street SYDNEY NSW 2000 INVENTION TITLE: A WEIGHTED GEL BLANKET DETAILS OF ASSOCIATED APPLICATION NO(S) Nil The following statement is a full description of this invention including the best method of performing it known to me: m:\docs\20101037\1 95787.doc 2 A WEIGHTED BLANKET TECHNICAL FIELD The present invention relates to weighted blankets and, more particularly, to a weighted blanket for therapeutic use. 5 BACKGROUND ART Weighted blankets have been used to provide deep pressure touch stimulation therapy to people with a range of conditions including Autism, Attention Deficit Disorder, Attention Deficit Hyperactivity Disorder, Bi-Polar Disorder, Dementia, Pervasive Developmental Disorder, Sensory Processing 10 Disorder and other conditions which cause anxiety, stress and agitation. The pressure provided by the weighted blankets makes the people with these conditions feel secure and calm and has been shown to stimulate the release of the brain chemical serotonin which enhances mood, memory and cognition. At night, or in the absence of light, serotonin is used to make the hormone 15 melatonin, which has been shown to stimulate sleep. The weighted materials used in prior art weighted blankets include steel pellets, plastic beads, sand, stones, wheat, corn, rice and beans. In these prior art weighted blankets, the weighted material fills pouches which are inserted into a plurality of pockets in the blanket. Other weighted blankets comprise 20 steel pellets laminated between two sheets of material. There are numerous problems with prior art weighted blankets, including that the weighted material (or the pouches containing it) must be removed from the blanket prior to washing, the weighted material often cannot be readily heated or cooled, the weighted material is not evenly distributed across the 25 blanket, the weighted material readily shifts during use of the blankets and the blankets are often bulky, uncomfortable to use and accordingly, their therapeutic use has been minimised. 19/07/10 3 Therefore, it is an object of the present invention to substantially ameliorate at least some of the problems of the prior art. DISCLOSURE OF INVENTION According to a first aspect of the present invention, there is provided a 5 weighted body when used in deep pressure touch stimulation therapy, wherein the weighted body has a plurality of gel filled cells. The cells of the weighted body may be arranged in columns and rows. The cells may also be connected by passageways that communicate the gel. The gel may be adapted to radiate or absorb heat after the weighted 10 body has been heated or cooled. Preferably, the gel may be a mixture comprising carboxy-methyl cellulose, propylene glycol and water. More preferably, the gel is a mixture comprising about 75% carboxy-methyl cellulose, about 20% propylene glycol and about 5% water. In a preferred form, the body has a size of at least 120 cm x 80 cm. 15 According to a second aspect of the present invention, there is provided a weighted blanket, wherein the weighted blanket comprises a cover and the weighted body. Preferably, the weighted body is adapted to be inserted and retained in the cover by retaining means. More preferably, the retaining means comprise 20 press studs and sockets. The cover may be adapted to be washable. According to a third aspect of the present invention, there is provided a method of providing deep pressure touch stimulation therapy, wherein the method comprises applying at least the weighted body to a patient. Preferably, the weighted body weighs between 9% and 13% of the 25 weight of the patient. More preferably, the weighted body weighs 11% of the weight of the patient. The height of the weighted body may be approximately 115% of the height of the patient, and the width of the weighted body may be 19/07110 4 approximately 80% of the height of the weighted body. It is preferred that the weighted body weighs between 0.5 kg and 15 kg. In a preferred form of the present invention, the method comprises the additional step of inserting the weighted body into a cover forming a weighted blanket before application to the 5 patient. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view of the weighted blanket according to a preferred embodiment of the present invention; Fig. 2 is a plan view of the cover of the weighted blanket of Fig. 1; 10 Fig. 3 is a plan view of the body of the weighted blanket of Fig. 1 at a preliminary stage of construction; Fig. 4 is a plan view of the body of Fig. 3 being filled with gel; and Fig. 5 is a plan view of the body of Fig. 3 filled with gel and sealed. BEST MODE FOR CARRYING OUT THE INVENTION 15 The weighted blanket 10 according to an embodiment of the present invention is shown assembled in Fig. I and comprises a cover 12, a weighted body 14 located within the cover 12 and a plurality of cells 16 arranged in the weighted body 14. The cells 16 are filled with a gel 18 so as to provide weight to the weighted body 14 located within the cover 12. 20 The cover 12 is shown separately in Fig. 2 may comprise two quilt layers (not shown). Each quilt layer may comprise a top fabric, wadding (an insulating material made of cotton, polyester, wool and/or mulberry silk) and a bottom fabric. The top fabric may be coloured and ornamented with a pattern or other motifs for aesthetic appeal, whereas the bottom fabric may be a plain white or 25 other coloured material (as it will not be visible to a user), in order to reduce the cost of manufacture of the cover 12. The amount of wadding can be increased 19/07/10 5 or decreased depending on the desired thermal resistance of the cover 12. The top and bottom fabric may be made of cotton, for instance. The top fabric and the bottom fabric are stitched together with the wadding in between. Stitches may be made around the permitter of the top 5 fabric and the bottom fabric. Stiches may also be made at regular intervals forming a grid and across the top fabric and bottom fabric. The two quilt layers are placed on top of each other with the bottom fabric facing outward. Stitches are made around three of the four sides of the two quilt layers to join them together. 10 Press studs comprising a cap stud 22 and a socket 24 are used to fasten the cover 12 to the weighted body 14 so as to hold the weighted body 14 in place within the cover 12. The cap stud 22 is attached to the cover 12 (see Fig. 2) to engage the sockets 24 which are attached to the weighted body 14 (see Fig. 3). In one embodiment, the cap stud 22 and socket 24 are located at 15 the corners of the cover 12 and the weighted body 14 and also along the sides of the cover 12 and the weighted body 14. The two quilt layers are then turned inside out through the side which is left unstitched, so that the top fabric of the two quilt layers faces outwards. A zipper 20 may be placed on the side of the cover 12 which is left open. The 20 weighted body 14 may be inserted into the cover 12 through the zipper 20. The weighted body 14 is shown in Fig. 3 at a preliminary stage of construction. The weighted body 14 may be constructed from two sheets of a thermoplastic material, such as nylon (polyamide) or any similar materials (e.g. low-density polyethylene or polypropylene) that are fluid impermeable and able 25 to be washed and resist high and low temperatures. The two sheets are cut to the required size and then welded together by sending a high frequency current through the two sheets when placed between two sealing electrodes or dies. 19/07/10 6 The cells 16 may be arranged in a pattern other than that shown in Fig. 3, but preferably the pattern is regular so that the weight within the blanket 10 is evenly distributed so that the blanket 10 is comfortable to use. Likewise, the cells 16 are preferably square shaped so as to maximise the area 5 of the weighted body 14 which is able to be filled with gel 18, but may also be round, rectangular or any other shape. In one embodiment, the cells 16 have passageways 28 arranged in columns throughout the length of the weighted body 14, so as to facilitate the manufacture of the weighted body 14. Referring to Fig. 5, a reservoir 30 filled 10 with the gel 18 is connected to a pump 32, which is attached to a hose 34 which is connected to a tube 36. The tube 36 is inserted along a column through the passageways 28 and the gel 18 is pumped through the tube 36 and deposited into the individual cells 16 until all of the cells 16 are filled with gel 18 as shown in Fig. 6. 15 Having passageways 28 down the length of the weighted body 14 also aids the user to move some of the gel 18 up and down the weighted blanket 10, whilst preventing the gel 18 from moving sideways in use overnight as it would be inclined to do if the passageways 28 extend laterally instead of or in addition to lengthways. 20 A suitable gel 18 may be a mixture comprising about 75% carboxy methyl cellulose, about 20% propylene glycol and about 5% water. An industrial blender may be used to mix the components of the gel 18 for approximately 2.5 hours. The gel 18 is adapted to be heated or cooled. Thus, the weighted body 14 may be placed in a clothes dryer or a bath filled with hot water to heat the 25 gel 18 which will retain the heat for some time within the weighted body 14. The weighted body 14 may also be placed in a refrigerator in order for the gel 18 to 19/07/10 7 be cooled. The weighted body 14 may also be heated without first removing the cover 12 when a clothes dryer is used to heat the device. A pump 32 is used to inject the gel 18 into the cells 16 (see Fig. 5). When the pump 32 is turned on for a certain length of time, a certain amount of 5 gel 18 will be injected into each cell (depending on the strength of the pump 32). The amount of time the pump 32 is turned on will determine how much gel 18 is pumped into each cell. For instance, leaving on the pump 32 on for 4 seconds will deposit 23.6 grams of gel 18 into a cell 16. Once the weighted body 14 has been filled with gel 18, the seal 38 is 10 made along the bottom edge of the weighted body 14 (see Fig. 5) to retain the gel 18 within the lower row of cells 16. The surface of the weighted body 14 is waterproof so that it may be washed or wiped down after use. The weighted body 14 may be removed from the cover 12 via the zipper 20 so that the cover 12 may be put into a washing machine. The weighted body 14 may also be 15 wiped clean with warm soapy water. The weighted body 14 of the present invention may be used with or without the cover 12 to provide deep pressure touch stimulation therapy to patients having any one or more of the following conditions: Autism, Attention Deficit Disorder, Attention Deficit Hyperactivity Disorder, Bi-Polar Disorder, 20 Dementia, Pervasive Developmental Disorder, Sensory Processing Disorder and other conditions which cause anxiety, stress and agitation. Whenever patients having these conditions are in a state of agitation or distress, the patient may be placed under the weighted body 14 or wrapped in the weighted body 14 in order to calm the patient. The pressure applied by the weight of the 25 weighted body 14 enables the patient to feel secure. The size and weight of the weighted body 14 for use in treating patients can vary depending on the degree of pressure required to be applied. It has 19/07/10 8 been found, however, that the weight of the weighted body 14 should be approximately 11% of the weight of the patient. Further, the length of the weighted body 14 should be approximately 15% longer than the height of the user and the width of the weighted body 14 should be approximately 80% of 5 the height of the weighted body 14. Below in Table 1 are provided some dimensions for various embodiments of weighted body 14 which have been constructed for patients between 20kgs and 80kgs. Weighted body Number Gel 18 per Weighted User weight 14 of cells cell 16 body 14 (kg) size 16 (kg) Weight (cm) (kg) 120 x 80 24 0.10 2.0 20.0 140 x 100 35 0.85 3.0 30.0 160 x120 48 0.93 4.5 45,0 180 x120 54 1.11 6.0 60.00 200 x140 70 1.14 8.0 80.0 200 x 180 90 1.33 12.0 120.0 (c 10 Table 1. Dimensions and weights for various different sizes of the weighted body 14. It will be apparent to persons skilled in the art that various modifications may be made in details of design and construction of the body described above without departing from the scope or ambit of the present invention. 15 In particular, whilst the invention has been described by reference to the term "weighted blanket" and described as having a discrete weighted body 14 and a cover 12, the person skilled in the art will appreciate that the invention is 19/07/ 10 9 broader in scope. For instance, the weighted body 14 may also be provided for use without a cover 12. In some cases, they may even be provided without retaining means (such as the press studs) as they may not need to be secured into any cover. The weighted body 14 may be made from sheets of polymeric 5 materials that have been extruded or otherwise produced in a way that results in them having a soft, fabric like surface. In such a case, they may be sold for use in the summer without any cover 12. Blankets 10 may be made of any custom size to suit any particular user. Further, any method of construction may be used to make the cover 12 10 of the blanket 10, other than the method described herein. Any pattern of cells 16 may be constructed in the weighted body 14 other than the grid like arrangement of square cells 16 described herein, for instance, circular shape cells 18 may be used in a regular or irregular arrangement. Any suitable thermoplastic or other material may be used to construct the weighted body 14 15 and any suitable gel 18 may be used. INDUSTRIAL APPLICABILITY The present invention has applications in the bedding and therapeutic industries. 20 19/07/10