WO2006007637A1

WO2006007637A1 - A biodegradable golf tee and method of making the same

Info

Publication number: WO2006007637A1
Application number: PCT/AU2005/001045
Authority: WO
Inventors: Andrew Kongas
Original assignee: Safe-Tees Down Under Pty Ltd
Priority date: 2004-07-16
Filing date: 2005-07-15
Publication date: 2006-01-26

Abstract

This invention is directed towards a degradable shaped product which is typically a golf tee, the golf tee including a mineral composition and a binder. Also disclosed is a method of producing the shaped product. A pair of press or die members (10), which together define a cavity (13), is used to form the mixture into the required shape. At least one piston member (14) is used to apply pressure to the mould material in order to form the shaped product.

Description

A Biodegradable Golf Tee and Method of Making the Same

Field of the Invention.

This invention is directed to a biodegradable shaped product and is particularly directed to an improved biodegradable golf tee. Background Art.

Golf tees are conventionally made of plastic or wood. These materials provide the tee with strength and rigidity. The material also enables the golf tees to be manufactured quite inexpensively. One disadvantage with these conventional golf tees is that the tees are often lost or broken and therefore left on the ground by a golfer. These tees are not biodegradable and become a hazard. For instance, discarded tees can become a striking hazard during mowing as a mower blade can strike the tee at great force and can fling the tee a great distance. Also, it is possible for the tees to damage or unnecessarily cause wear and tear to the mower.

Golf tees which are biodegradable are known. One type of golf tee is made from pressed fibrous plant material such as sugarcane bagasse, wheat stalk, maize etc. While this does provide a biodegradable golf tee, the golf tee does not cause any enrichment or any benefit to the soil.

Therefore, it is also known to provide golf tees that have impregnated materials to provide beneficial properties to the ground. For instance, it is known to impregnate a biodegradable golf tee with a chemical fertiliser and herbicide. As the tee breaks down, the fertiliser is released. A disadvantage with this arrangement is that fertilisers and herbicides are a source of toxicity to the soil and high applications and longer applications of chemical fertilisers can cause the soil to become "dead".

Herbicides applied to the soil over long periods of time can also result in build-up of toxins. On a more practical note, a fertilizer-containing tee will create a patch of green grass as it degrades which can be quite unsightly.

It is also known to impregnate a golf tee with grass seed, the thinking being that as the golf tee degrades, the seed will germinate.

A disadvantage with various impregnated golf tees is that in order for the impregnated material to have a beneficial effect, the amount of impregnated material must be quite large. For instance, the known golf tee with an impregnated fertiliser requires the amount of fertiliser to be quite high. This, in turn, can cause weakening of the golf tee which can only be compensated by using various binders and strengthening agents, some of which maybe toxic, difficult to degrade, and which may increase the cost of manufacture of the golf tee.

Therefore, there would be an advantage if it were possible to provide a biodegradable golf tee containing a soil improvement agent but which does not contain a chemical herbicide or a chemical fertiliser of the type that destroys soil activity.

It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country. Obj ect of the Invention.

It is an object of the invention to provide a biodegradable golf tee that may overcome at least some of the above-mentioned disadvantages or provide the consumer with a useful or commercial choice. hi one form, the invention resides in a degradable shaped product, the shaped product comprising a mineral composition and a binder.

Suitably, the shaped product is adapted to degrade or break down due to the weather, abrasion or impact. Typically, the shaped product will be biodegradable.

The invention is particularly applicable to the formation of golf tees. The shaped product will hereinafter be described with reference to a golf tee but it is to be understood that it may include any shaped product having a composition according to the invention or formed according to a method of the invention.

The mineral composition may comprise one or more compounds from the group consisting of calcium, carbon, sulphur, nitrogen, phosphorus, potassium, iron, magnesium, sodium, boron, copper, zinc, manganese, molybdenum, cobalt and selenium, with the proviso that the mineral composition does not consist essentially of chemical fertilisers of the type that reduce soil activity.

Thus, careful choice of the mineral composition can result in a build-up in soil fertility of feeding both the soil and plant as opposed to pure chemical fertilisers that can feed the plant but will kill the soil.

Suitably, the mineral composition contains a majority of the above components, and typically will contain substantially all the above components and preferably the mineral composition contains all the above components. The amount of calcium may range from between 5-25% by weight and preferably between 10-15% and most preferably approximately 12.4%.

The amount of carbon may range from between 2-30% and preferably between 5-15% and most preferably approximately 10.4%. The amount of sulphur may range from between 1-20% and preferably between 3-10% and most preferably approximately 5.6%.

The amount of total nitrogen may range from between 1-20% and preferably between 2-10% and most preferably approximately 4.1%. The nitrogen may comprise ammonium and nitrate. It is preferred that the majority of the total nitrogen is in the ammonium form. Thus, the composition may comprise between 1- 15% ammonium and preferably between 2-10% ammonium and most preferably approximately 4.09% ammonium. The composition may comprise between 0.001-1% nitrate and preferably approximately 0.01% nitrate. The nitrates may be provided as ammonium nitrate. The amount of total phosphorus may range from between 0.1-20% and preferably between 1-10% and most preferably approximately 2.1%. The phosphorus may be in the form as phosphate, water soluble phosphorus, citrate soluble phosphorus and citrate in soluble phosphorus. It is preferred that the majority of the total phosphorus is in the phosphate form. The phosphorus may be provided as a superphosphate.

The amount of potassium may range from between 0.1-10% and preferably between 1-5% and most preferably approximately 2.1%.

The amount of iron may be between 0.1-10% and preferably between 0.5-5% and most preferably approximately 1.4%. The amount of magnesium may be between 0.1-5% and preferably between 0.5-2% and most preferably approximately 0.8%.

The amount of sodium may be between 0.1-5% and preferably between 0.1-1% and most preferably approximately 0.3%.

The boron, copper, zinc, manganese, molybdenum, cobalt and selenium may comprise trace elements and may be present in trace elements amounts. The trace elements amounts may be between 1 ppm-5000 ppm. Typically, the amount of boron may be between 100-500 ppm and preferably about 336 ppm, the amount of copper may be between 500-1500 ppm and typically about 790 ppm. The amount of zinc may be between 300-1000 ppm and typically about 753 ppm. The amount of manganese may be between 100-800 ppm and typically about 392 ppm. The amount of molybdenum may be between 1-100 ppm and typically about 38 ppm. The amount of cobalt may be between 1-20 ppm and typically about 6 ppm. The amount of selenium may be between 10-200 ppm and typically about 83 ppm. An amount of urea may be added.

The mineral composition may have a particle size suitable to enable it to be impregnated or form part of a golf tee. Typically, the mineral composition will be relatively finely ground and may have a particle size of between 0.001-5 millimetres.

The mineral composition may be created by any suitable method including co-grinding, mixing, and any other suitable technique. It is not considered that the invention should be limited by any method by which the mineral composition is formed. The golf tee will typically comprise a binder to hold the minerals together and to provide the tee with acceptable properties of strength, durability and the like. The binder may comprise an organic binder or a nonorganic binder or a composite binder. The binder may comprise a polymer and may comprise a water soluble binder. Typical binders may include gums such as gum arabic, xanthan gum, lignosulphonates, starch, polyhydroxybutyrate, polylactic acid, polycaprolactone, polybutylene succinate, polybutylene succinate/adipate, polybutylene succinate carbonate, polyvinyl alcohol and cellulose acetate. Other preferred binders may include di-calcium phosphate, guano, sugars such as glucose, castor or icing sugar, or mannitol. The binder may be a thermoplastic binder by which is meant that the binder softens or even becomes a liquid when heated as this may facilitate formation of the golf tee. Alternatively, the binder may comprise a curable or hardenable binder, including binders that can cure or harden in air, by heat, by a catalyst, or by other means. The amount of binder in the golf tee may vary depending on the type of binder used, but ultimately the golf tee should be sufficiently durable for proper use. The amount of binder may therefore be between 5-90% by weight of the golf tee. It is preferred however that the amount of binder is minimised in order to maximise the amount of mineral composition in the golf tee.

The shaped product of the invention may include any one or more of dicalcium phosphate, magnesium phosphate, magnesium sulphate, glucose or other sugar derivatives, dolomite or lime hydrates, bauxite, bentonite, microfibres such as corn, wheat or rice husks

The binder and the mineral composition may be mixed together or formed together by any suitable means, which may include mixing, co-extrusion, melting, fluidising, or any other suitable means. It is not considered that the invention should be limited to any particular manner by which the binder and the mineral composition are put together.

According to a particularly preferred embodiment, the material to be pressed will typically include approximately 60% by weight binder, approximately 35% by weight minerals, and 5% by weight of release agent to prevent the formed product "sticking" to the die surfaces. The mixed material can then be subjected to a heating and pressure step in a mould to form the golf tee. The heating may be anything from room temperature up to 200° centigrade. The pressure may be anything from atmospheric pressure up to 50 atmospheres. The heating and pressure time may be anything from one minute up to one hour. In order to provide sufficient mineral composition to a golf tee, the golf tee may have a peculiar shape which is different to the normal shape of a golf tee. A normal golf tee will comprise a cup-like top on which the golf ball can be placed, and a spike-like portion that can be pushed into the ground, hi an embodiment, the present invention may comprise a golf tee which comprises a cup-like top on which the golf ball can be placed, and a spike-like portion that can be pushed in the ground, the spike-like portion being characterised by having at least one thickened area along the spike-like portion.

The thickened area enables an additional amount of mineral composition to be used in the manufacture of the golf tee which provides better beneficial results to the soil. Another advantage is that the thickened area provides a visual identifier to this type of biodegradable golf tee so that a groundskeeper does not pick up the golf tee; he simply leaves it to degrade. Another advantage is that the thickened area can be positioned on the spike-like portion to provide a depth indicator when pushing the tee into the ground. For this reason, the golf tee may be provided with a plurality of thickened portions which may be spaced apart. Suitably, the length of the golf tee is such that one or two thickened portions can be spaced along the golf tee. The thickened portion may comprise a "collar" shaped part. The thickened portion may have a "thickness" of between 1-3 times the thickness of the remainder of the tee.

It is also envisaged that the cup-like portion may be larger than usual again to provide a greater amount of mineral composition to the golf tee and again to provide a visual identifier to this type of biodegradable golf tee.

The golf tee may contain other additives. For instance, it is envisaged that the golf tee may comprise a colour. The colour will preferably be a non-toxic colour and may comprise a food additive colour. The colour may be coated to the outside of the golf tee, impregnated into the golf tee or otherwise form part of the golf tee. If desired, the golf tee may contain a complex colour arrangement.

The product of the invention will generally only use dry powder components. However, some advantage may be gained by using a liquid or resinous compound such as a gum or similar. Also, the product of the invention may use sugar or similar as the binder as sugar has thermosetting properties. The product of the present invention may also include reinforcing fibres. Typically, the fibres will be biodegradable as well. The fibres may assist with the formation and retention of the shape of the product.

The golf tee may comprise an outer coating to provide gloss and a hardness to the outside of the golf tee. The coating may comprise a varnish, or any other type of polymer coating, non-polymer coating, coating composition and the like. The outer coating may also include a colour.

According to a particularly preferred embodiment, the product will be formed or manufactured using a dry-press process. The dry-press process may be similar to that used in the pharmaceutical industry. A preferred process is one utilizing a tableting press or similar.

According to a further aspect, the invention resides in a dry press process for manufacturing a shaped product, the process including the steps of filling a mould or die with a powder formulation, applying a force to the powder formulation whilst in the mould or die to form the shaped product and ejection of the shaped product from the mould or die.

It is preferred that the powder formulation is a dry powder formulation and that any binders or other components used are in a powder form. If one or more constituents are provided in a form other than powder, it is preferred that they be dry. If one or more constituents are provided in a "wet" form, the constituents are preferably provided so that injecting or otherwise filling the mould or die is easily an quickly accomplished without compromising the shaped product or, more importantly, compromising the mould or die surfaces by leaving portions of the formulation behind after the ej ection step .

Tableting presses are generally used for uniaxial pressing powdered materials into shaped tablets or compacts. Tableting presses usually operate at high speeds. Parts can often be pressed and sintered to dimensional tolerance levels that do not require additional machining. For demanding applications, some shaped products may require subsequent coining/repressing, infiltration, hot pressing or forging to reach the required density and strength.

Tableting presses are usually designed in two configurations: multi¬ station tableting presses and single station presses. Multi-station tableting presses, also referred to as rotary presses, use a punch and die system with multiple stations or punches for compacting materials into simple flat or multilevel shaped parts like golf tees. Rotary types have a series of stations or tool sets (dies and punches) arranged in a ring in a rotary turret. As the turret rotates, a series of cams and press rolls control filling, pressing and ejection. High volume production facilities will typically use high-speed automatic rotary presses. Single station presses consist of a single tool set (die and punch set) in a die table. Single action opposed ram presses use a die with both upper and lower punches. Anvil type presses have only a die and single lower punch. Single station compacting presses are available in several basic types such as cam, toggle/knuckle and eccentric/crank presses with varying capabilities such as single action, double action, floating die, movable platen, opposed ram, screw, impact, hot pressing, coining or sizing.

When working with tableting presses, force is generally the appropriate measure to determine the degree to which materials may be compacted. By contrast, pressure is the determining factor when working with isostatic presses. The maximum operating press load or force required to reach the desired density during part production when using a tableting press may be expressed as follows:

Press Load = Required compaction pressure (psi) for the material x Part's Projected Area (sq. in.)

It is likely that pressures of at least 1 tonne of force and upward will be used according to the process of the invention, and the pressures used are more likely to be an order of magnitude larger than this minimum pressure.

Additionally, the functionality of a given tableting press may be determined by three important specifications: unit rate production, the diameter or width of the die cavity, and maximum internal length of the cavity. Unit rate production is the number of units produced per minute or hour. The unit's capacity may be stated in terms of compacts, products, strokes or cycles per unit time. Diameter and length of the inner cavity are determinants of the maximum size of the die that the press may accommodate. This in turn reflects the size or type of compact that the press can produce.

Lubricants (such as magnesium stearate, which is often used in concentrations of 0.5wt%) are often used in tablet press applications to reduce the compression force during tableting, to avoid product build-up on the tablet press tools (on the dies as well as on the punches), to get a uniform tablet colour and to make a smooth tablet surface. The lubricants may be added to the powder mix or applied to the die surfaces. According to a further aspect, the invention may reside in a press for manufacturing a shaped product from a formulated mould material, the press including at least a pair of mould or die members which together define a cavity in a required shape adapted to receive the mould material, and at least one piston member adapted to apply pressure to the mould material to form the shaped product. The press will preferably include a pair of spaced apart plate members which either are, or mount the mould or die members. The plate members are generally oriented in an opposed configuration with faces of respective plate members being opposing faces and are adapted to be move toward and away from one another in the steps of the pressing cycle. Typically the mould or die members are mounted to the plates. One or more stop members may be provided to limit the closure distance between the plate members. This may prevent components of the press which are mounted on opposing faces of the plate members from being damaged during the pressing step. There will generally be a plate member which is fixed in position and a plate which is movable toward and away from the fixed plate to open and close the die.

The mould or die members may both suitably be block members which include one or more cavities therein, which together form a three dimensional shape of a product to be formed. Alternatively, and more preferred, is that the die members are provided as a set including a die member and a punch. The mould or die members are suitably securely but removably mounted relative to the opposing facings of the plate members. There will generally be at least a pair of mould or die members but it is also envisaged that more than two mould or die members may be provided to define a single cavity or more than one cavity may be provided. The mould members will be mounted relative to the plate members so that when the plate members are moved together, the mould members are in alignment.

According to a most preferred embodiment, the press may be provided with a fixed die portion with a cavity defining the shape of at least part of the shaped product and four other movable, pressure applying portions. The four movable portions will typically include a moveable punch portion which preferably defines at least part of the shaped product, a pair of opposed filler guide portions, each filler guide portion mounted adjacent the fixed die portion and movable to define a filler gate for the cavity in a first condition and a free condition, and the at least one piston member.

Typically, the directions of movement may be defined according to the shape of the product to be formed, and most preferably, with respect to the axis of the product having the greatest length. The die may be provided so that filling of the cavity takes place in a plane perpendicular to the axis of longest axis of the product, and generally a gravity feed method is used. The punch member will also typically move back and forth in this direction. The filler guide portions will typically move back and forth in a plane which is perpendicular to both the longest axis of the product and the punch member movement plane. The at least one piston member generally moves in a plane which is parallel to the longest axis of the product. This configuration results in a multi-axial press which may form a more consistent product.

The mould or die members will typically be manufactured of a strong and rigid material such as a metal and will be generally be tool steel or the like. At least one piston member is provided to apply pressure to the mould material to form the shaped product Generally, only a single piston member per die cavity will be provided. The piston member will typically be associated with a member or assembly that drives the piston member in a reciprocating motion to apply force to the material in the die cavity. The at least one piston member will generally be mounted on one of the plate members, and most preferably on the fixed plate member. The piston member will typically apply the force to the material in a direction substantially parallel to the longest axis of the shaped product.

According to a particularly preferred embodiment, the piston member of the present invention will have a first end which is located and movable to apply the compression force to the material in the die, and a second end provided with an angled portion. The angled portion will preferably be angled outward such that the portion of the angle member closest to the plate member is further from the die than the portion of the angled member further from the plate member. Typically, the moveable plate member will be provided with an corresponding second angled portion that engages with the angled portion on the piston member to drive the piston member to apply force on the material in the die. The second angled portion will preferably be angled outward such that the portion of the second angle member closest to the plate member to which it is mounted is closer from the die than the portion of the angled member further from the plate member. Due to the configuration of the respective angle members, as the plates are closed, the piston is driven to apply force to the material in the die.

Control of the material flow into the die cavity is generally a key factor in producing well formed products. The material preferably flows rapidly and uniformly into the die, minimizing sharp direction changes, turbulence, and entrapped air. A key feature in die design is typically the positioning of the gates - the passages through which the material to be pressed is fed into the die cavity. Well-designed gates are usually positioned to permit rapid flow into the thicker sections of the die cavity and to provide smooth flow paths which minimize turbulence in the material to be pressed. According to a preferred embodiment of the invention, the gate may be provided in the form of a filler guide. The filler guide or plate will typically be a planar plate with an opening therein to allow the ingress of the material to be pressed.

The opening will typically also be shaped to allow the movable die punch to pass. The shaped product will typically be formed in a press having multiple cavities to form multiple products simultaneously. The gating into each cavity typically has a large cross-section to produce high-volume flow into the die cavities.

This is particularly the case when dealing with powered materials where the twin problems of arching and rat-holing of the material when conveying it are encountered. Preferably, the filler guide is provided on a side corresponding to the longest dimension of the shaped product. This generally produces smooth, rapid laminar flow into the cavity.

Overflow areas may be provided in the mould or die to reduce/prevent porosity in the pressing and promote complete material fill into sections of the cavity which are further from the filler guide. Generally, overflow areas on each cavity are on the opposite side of the cavity to the gate. The overflow areas are normally tabular in shape and positioned at the parting line between the mould or die members. The overflow areas on cavities furthest from the supply of the material may be connected by a vent line to permit pressure equalization and to reduce back pressure in the die cavities.

After pressing, a further, die trimming step may take place to remove the gates and removes "flash" from portions of the shaped product, particularly the periphery of the shaped products.

The press described above is a preferred form only and it is envisaged that other forms of press may be used. For example, the press may be provided in the form of a pair of counter-rotating rolls, each having a die portion located circumferentially and defining a pressing zone between the rolls, similar to that in a crushing roll assembly.

Brief Description of the Drawings. An embodiment of the invention will be described with reference to the following drawings in which:

Figure 1 illustrates a golf tee according to an embodiment of the invention. Figure 2 illustrates a process used to manufacture the shaped product according to a first preferred embodiment.

Figure 3 illustrates a process used to manufacture the shaped product according to a second preferred embodiment. Figure 4 illustrates one half of a press used to form the shaped product according to a preferred embodiment of the invention.

Figure 5 illustrates the mating half to the half of the press used to form the shaped product as illustrated in Figure 4.

Figure 6 illustrates the assembled press including the two halves illustrated in Figures 4 and 5.

Description of the Preferred Embodiment

Referring to figure 1, there is illustrated a golf tee and the dimensions of the golf tee according to the embodiment are given in figure 1. The golf tee has a cup portion on which a golf ball can be placed and a spike portion which is pushed into the ground. The golf tee is unusual in configuration as it contains a pair of thickened portions on the spike portion. hi the particular embodiment, the golf tee is made from a particular mixture of minerals and a binder. A typical analysis of the mineral mixture is as follows: Calcium 12.4%, carbon 10.4%, sulphur 5.6%, nitrogen total 4.1% containing ammonium 4.09% and nitrate 0.1%, total phosphorus 2.1%, as phosphate 4.8%, containing water soluble phosphorus 0.6%, citrate soluble phosphorus 0.4%, and citrate insoluble phosphorus 1.2%, potassium 2.1%, iron 1.4%, magnesium 0.8%, sodium 0.3%, boron 336 ppm, copper 790 ppm, zinc 753 ppm, manganese 392 ppm, molybdenum 38 ppm, cobalt 6 ppm and selenium 83 ppm.

The mineral mixture is a dark grey powder and is mixed with a binder. The mixture is placed in a mould and cured and the mould opened to provide the biodegradable tee.

The particular shape of the golf tee enables a larger than normal amount of minerals to be added to the golf tee.

The particular shape can also coincidentally form a "depth indicator" to the golf tee and can also provide a visual indication that this type of tee, when discarded, can be left on the ground as it will enrich the soil. A multi-station tableting press, also referred to as rotary press will generally be used to form the shaped product.

There are two main processes which can be used to form the shaped product according to the preferred embodiment. The first preferred process is illustrated in Figure 2. In this process, a predetermined amount of lubricant is added to a predetermined amount of granules or free-flowing bulk solids before it will be compressed in the tablet press.

The granules or free-flowing bulk solids, as well as the lubricants, are fed into a batch mixer. After a defined mixing time, the mixture is transferred with a pneumatic or mechanical conveying device and fed into the tablet press.

As the granules and lubricants vary greatly in particle size and in bulk density, the risk of de-mixing may be quite high with this process. That means that it is difficult to reach a uniform mixture. Therefore many manufacturers tend to overfeed lubricants so that the risk of a too low lubricant concentration in a tablet is minimised.

The second preferred process is illustrated in Figure 2. In this process, the granules or free-flowing bulk solids are transferred with a pneumatic or with a mechanical conveying device to the tablet press.

The lubricants are fed continuously through a funnel into an injector, which is supplied with compressed air. The air in the pneumatic conveying line conveys the lubricant to a nozzle, which is fixed in the tablet press. The nozzle is mounted in a way that all surfaces of the tablet press tools, which are in contact with the granules or free-flowing bulk solids (the dies as well as the punches), are uniformly powdered with lubricant. The dust created inside the tablet press is eliminated by an exhaust air system.

The press or die used to form the mixture into the required shape according to a preferred embodiment, is illustrated in Figures 4 to 6. The press includes a pair of mould or die members 10 which together define a cavity 13 in a required shape adapted to receive the mould mixture, and at least one piston member 14 adapted to apply pressure to the mould material to form the shaped product.

The press includes a pair of plate members 11, 12 which mount the mould or die members 10. The plate members 11, 12 are oriented in an opposed configuration with faces of respective plate members being opposing faces, and are adapted to be moved toward and away from one another in the steps of the pressing cycle. One plate member 11 is fixed in position and the opposed plate member 12, is movable toward and away from the fixed plate 11 to open and close the press. The mould or die members 10 are mounted to the plates 11, 12. A stop member 15 is provided to limit the closure distance between the plate members 11, 12 to prevent components of the press which are mounted on opposing faces of the plate members 11, 12 from being damaged during the pressing step.

The main die member 10 is a block member which includes at least part of a cavity 13 therein. This die member 10 together with a punch member 21 which includes at least part of a cavity 13 therein, together form a three dimensional shape of a product to be formed. The die member 10 is securely but removably mounted (using threaded fasteners such as screws 16 or the like) relative to the face of one of the plate members 11. The die member 10 and the punch member 21 are mounted to the plate members 11, 12 so that when the plate members 11, 12 are moved together, the die member 10 and the punch member 21 are in alignment.

According to the embodiment illustrated, the press is provided with a fixed die member 10 with a cavity 13 defining the shape of at least part of the shaped product and four other movable, pressure applying portions. The four movable portions include a moveable punch 21 which also defines at least part of the shaped product, a pair of opposed filler guide portions 22, each filler guide portion 22 mounted adjacent the fixed die member 10 and movable to define a filler gate for the cavity 13 in a first condition and a free condition, and the piston member 14.

The directions of movement of each movable portion are defined according to the shape of the product to be formed, and most preferably, with respect to the axis of the product having the greatest length. The die member 10 is provided so that filling of the cavity 13 takes place in a plane perpendicular to the axis of longest axis of the product, and generally a gravity feed method is used. The punch member 21 moves back and forth in this direction. The filler guide portions 22 move back and forth in a plane which is perpendicular to both the longest axis of the product and the punch member 21 movement plane. The piston member 14 moves in a plane which is parallel to the longest axis of the product. This configuration results in a multi-axial press which may form a more consistent product.

At the start of the pressing cycle, all movable portions except the piston member 14 will be in the pressing position. The material will then be fed into the cavity 13 and the punch member 21 moves downward to press the material. The piston member 14 is driven laterally to apply force to the material in the cavity 13 at the same time, compressing the powder to form the product. Before the punch member 21 is raised, the filler guide members 22 are withdrawn from their pressing position. The punch member 21 are then retracted and the shaped product ejected from the cavity 13. One or more ejection means, such as pins (not shown), will generally be provided for this.

The die member 10 and the punch member 21 are manufactured of tool steel or the like.

The piston member 14 is provided to apply pressure to the mould material to form the shaped product The piston member 14 is mounted on the fixed plate member 11.

According to the preferred embodiment illustrated, the piston member 14 has a first end 17 which is movable to apply the compression force to the material in the cavity 13, and a second end 18 provided with an angled portion 19. The angled portion 19 is angled outward such that the portion of the angle member 19 closest to the fixed plate member 11 is further from the cavity 13 than the portion of the angled member 19 further from the plate member 11. The moveable plate member 12 is provided with a corresponding second angled portion 20 that engages with the angled portion 19 of the piston member 14 to drive the piston member 19 to apply force on the material in the cavity 13. The second angled portion 20 is angled outward such that the portion of the second angle member 20 closest to the plate member 12 to which it is mounted is closer from the cavity 13 than the portion of the angled member 20 further from the plate member 12. Due to the configuration of the respective angle members 19, 20, as the plates are closed, the piston member 14 is driven to apply force to the material in the cavity 13.

Throughout the specification and the claims (if present), unless the context requires otherwise, the term "comprise", or variations such as "comprises" or "comprising", will be understood to apply the inclusion of the stated integer or group of integers but not the exclusion of any other integer or group of integers.

Throughout the specification and claims (if present), unless the context requires otherwise, the term "substantially" or "about" will be understood to not be limited to the value for the range qualified by the terms.

Claims

Claims:

1. A degradable golf tee, the golf tee including a mineral composition and a binder.

2. A degradable golf tee according to claim 1 wherein the mineral composition includes one or more compounds from the group consisting of calcium, carbon, sulphur, nitrogen, phosphorus, potassium, iron, magnesium, sodium, boron, copper, zinc, manganese, molybdenum, cobalt and selenium, with the proviso that the mineral composition does not consist essentially of chemical fertilisers of the type that reduce soil activity.

3. A degradable golf tee according to claim 1 including approximately 60% by weight binder, approximately 35% by weight mineral composition, and 5% by weight of a release agent.

4. A degradable golf tee according to claim 1 wherein the mineral composition includes boron, copper, zinc, manganese, molybdenum, cobalt or selenium in trace elements amounts.

5. A degradable golf tee according to claim 1 wherein the mineral composition has a particle size of between O.OOlto 5 millimetres.

6. A degradable golf tee according to claim 1 wherein the binder is chosen from the group including polymers, water soluble binders, gums, gum arabic, xanthan gum, lignosulphonates, starch, polyhydroxybutyrate, polylactic acid, polycaprolactone, polybutylene succinate, polybutylene succinate/adipate, polybutylene succinate carbonate, polyvinyl alcohol, cellulose acetate, di-calcium phosphate, guano, sugars including glucose, castor or icing sugar, or mannitol, and a thermoplastic binders.

7. A degradable golf tee according to claim 1 wherein the mineral composition and binder are dry powder components.

8. A degradable golf tee according to claim 1 including reinforcing fibres.

9. A degradable golf tee according to claim 1 including a lubricant material.

10. A press for manufacturing a golf tee from a formulated composition, the press including at least a pair of mould or die members which together define a cavity in a required shape adapted to receive the mould material, and at least one piston member adapted to apply pressure to the mould material to form the shaped product.

11. A press for manufacturing a golf tee according to claim 10 wherein, the press includes a fixed die portion with a cavity defining the shape of at least part of the golf tee, a moveable punch portion which defines at least part of the golf tee, a pair of opposed filler guide portions, each filler guide portion mounted adjacent the fixed die portion and movable to define a filler gate for the cavity in a first condition and a free condition, and at least one piston member.

12. A method for forming a golf tee from a powered material having the steps of filling a mould or die cavity with a powder formulation, applying a force to the powder formulation whilst in the mould or die to form the shaped product and ejection of the shaped product from the mould or die.

13. A method for forming a golf tee from a powered material according to claim 12, wherein material is fed into the cavity, the powder is compressed in a press having a multi-axial compression, and the portions of the press are disengaged from the formed golf tee in a predetermined order to minimize damage to the formed golf tee.