NZ544631A - Construction composition - Google Patents

Abstract

Disclosed is a composition for filing gaps between adjacent construction components including a resin, of a concentration between substantially 6 and 18% of the composition, expressed as the volume of the resin solids of the composition, a bulk particulate material, of a concentration between substantially 50 to 80% of the composition by volume, a calcium aluminate cement component, at a concentration between substantially 0.5 to 4 times the weight of the dry resin amount, and a liquid, at a concentration of between 10 and 30% of the composition by volume the composition characterised in that the calcium aluminate cement component is of a composition that does not release or cause the production of free lime, either during or after curing, wherein the composition does not include Ordinary Portland cement or free lime.

Description

PATENTS FORM NO. 5 Fee No. 4: $250.00 PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional No: 544631 Dated: 11 January 2006 Intellectual Property Office of N.Z. 1 0 JAN 2007 RECEIV E D CONSTRUCTION COMPOSITION WE Ridge-IT Limited, a New Zealand company of 282 Kahikatea Drive, Hamilton, New Zealand hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: James & Wells Ref: 125450/55 CONSTRUCTION COMPOSITION TECHNICAL FIELD This invention relates to a composition for use in the construction industry.

Specifically this invention relates to a composition which can be applied while wet 5 onto a second wet surface or base.

More specifically this invention relates to a composition which may be used for bedding and pointing a roof wherein it can be applied to a wet cement base.

BACKGROUND ART Cement based, clay or terracotta tiled roofs are present on a considerable 10 number of existing houses and are a popular choice for new home builders. Tiled roofs provide an aesthetically pleasing and easy care option for a roofing material.

In order to maintain the tiles and ridge tiles in the correct position, while providing a waterproof finished roof, it is necessary that the tiles are correctly bedded and 15 pointed.

On an angled roof the tiles overlap with the adjacent lower tile to provide a finish which allows easy water runoff without pooling between tiles. In most instances the bottom edge of an upper tile sits over the top edge of the tile below it. Bedding mortar may be laid evenly over the portion of a roof tile, onto which 20 another tile is to be positioned. This provides a watertight fill to the gap/join between overlapping tiles.

The ridge tile also has a layer of bedding mortar on which it sits over the top of the tiles on either side of the ridge. 2 The bedding mortar when cured creates a connection between the ridge, hip or barge and a tile beneath it or some other roofing component. This maintains the tile in position, even under harsh weather conditions, and provides a watertight finish.

Once the ridge, hip or barge tiles have been positioned using the bedding mortar, pointing, often using a different component is used to finish the edges of the ridges, hips or barges where gaps between the ridge, hip or barge have not filled with bedding mortar.

Traditionally ridge capping, especially on a steeply pitched roof involved bedding 10 the ridged capping in a standard cement mortar which is applied to reinforcing mesh sometimes held in place by a hooked nail, or wired to the roof battens.

This method has a number of significant disadvantages, including: it takes a considerable time to undertake, therefore increasing labour costs considerably. The cement mortar also had to cure before a pointing compound could be 15 applied. Again this increases the time and labour costs required for each job as it may be necessary to return to the site several times, especially in adverse weather conditions.

The usual bedding product/mortar is a mixture of sand and cement, this mixture is usually mixed in similar proportions to mortar used for other building purposes 20 such as bricklaying, for example a 4:1 or 3:1 ratio of sand to cement. The mortar provides a strong base, while being relatively cheap to manufacture.

Once the bedding of the roof capping or tiles has been completed, this has traditionally been required to cure completely before the application of a pointing compound.

Traditionally a sand cement mortar was also used as a pointing compound. 3 The use of a sand cement mortar as a pointing compound has a number of disadvantages, including the following: The mortar, bedding and pointing may crack if there is a slight movement of the roof structure. This can lead to an unsightly appearance of the roof, increased 5 maintenance, and water seeping or running into the roof structure. These can have significant impacts on the look and cost of house maintenance. Cracking may also occur for a number of other reasons such as high UV exposure, slight movement of the roof for example during an earthquake or someone walking on the roof to install a TV aerial or conduct other roof maintenance.

To overcome the above problems with traditional sand cement mortar being used as a pointing compound, a number of flexible pointing compounds have been developed. However these still have a number of significant disadvantages, including the following: Flexible pointing compounds generally take a considerably longer time to cure 15 than conventional mortar.

Flexible pointing compounds cannot be used over wet uncured cement, due to a lack of adhesion to same. Therefore the bedding must be applied, then the contractors or people constructing the roof must allow the bedding time to cure completely before returning to apply the pointing compound. This can considerably increase the time which a particular job takes.

Another significant disadvantage of existing flexible pointing compounds is that they can not be applied if there is the likelihood of rain within the required curing time. Therefore depending on the weather conditions, several trips may be required to complete the job. Again this can be extremely disruptive especially 25 during winter months when there is often a higher likelihood of rain. 4 One of the most significant disadvantages of existing flexible pointing compounds is that they must be applied in a thin layer with a typical thickness of only 3 to 5 mm to meet the manufacturer's guarantee. This means that the bedding must be applied very precisely in order to allow just the right amount of 5 space (3 to 5 mm) wherein the pointing compound is applied. This required accurate application of the bedding increases the time and concentration required to apply same. If the bedding is uneven resulting in an uneven thickness of the flexible pointing compound this can lead to the pointing compound not setting. If a flexible pointing compound is applied too thick the 10 product will not set and will instead stay soft, this may result in slumping of the pointing material and an unsightly and non-water resistant finish.

A further significant disadvantage of existing products is due to the use of Portland cement. This has a slow curing time and can lead to the development of efflorescence.

Efflorescence causes unsightly white lime deposits over the area in question through releasing free lime in the presence of water. This is both unsightly and weakens the cement from which the lime leaches, thereby potentially leading to or requiring increased maintenance.

One step products have also been developed which take the place of separate 20 bedding and pointing compounds.

One product, flexim ™ Roof Mortar, which acts as both the bedding and pointing compound in a one step process has been previously used in Europe. Although some success with this product has been observed in Europe, it does not suit the harsher weather conditions in other countries, such as New Zealand very well. 25 The product seems to have low resistance to UV irradiation, which leads to the product becoming brittle over a period of years and subsequently flaking off.

This increases maintenance costs with people having to have their roofs re-pointed. This problem is especially significant in countries such as New Zealand which have a high rate of sunshine per year and increased UV irradiation due to the lack of ozone over the country, thereby increasing the intensity of the UV. 5 This product is also relatively expensive to purchase, thereby also increasing the roofing costs.

One step products can also be more expensive, leading to increased construction and maintenance costs.

It would therefore be beneficial for those tiling roofs, or undertaking the 10 maintenance of same if there were available a product which could be used to point a roof which can be applied as a varied or thick layer, or if required be used as a one step product that is applied as a bedding and pointing compound all at one time.

All references, including any patents or patent applications cited in this 15 specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this 20 reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of 25 this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the 6 listed components it directly references, but also other non-specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

It is an object of the present invention to address the foregoing problems or at 5 least to provide the public with a useful choice.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

DISCLOSURE OF INVENTION According to one aspect of the present invention there is provided a composition, 10 including a resin, a bulk particulate material, and a cement component, characterised in that the cement component is of a composition that does not 15 release or cause the production of free lime, either during or after curing.

According to a second aspect of the present invention there is provided a method of manufacturing a wet composition, including a resin, a bulk particulate material, and a cement component wherein the cement component is of a composition that does not release or cause the production of free lime, either during or after curing, 7 the method characterised by the steps of a) preparing a wet formulation by mixing the resin with a liquid, b) preparing a dry formulation by mixing the bulk particulate material and the cement component, c) mixing the wet and dry formulations.

Alternatively, all the dry components may be mixed to form a dry re-emulsifiable resin which can then have water added to produce the final 'wet' product. This provides a quick and easy method for supplying the composition without the added bulk and weight of water.

Therefore according to another aspect of the present invention there is provided a method of manufacturing a wet composition, including a resin, a bulk particulate material, and a cement component wherein the cement component is of a composition that 15 does not release or cause the production of free lime, either during or after curing, the method characterised by the steps of a) preparing a dry formulation containing the resin, the bulk particulate material and the cement component, b) adding a liquid to the mixture from a). 8 According to another aspect of the present invention there is provided a method of filling gaps between adjacent construction components using a composition, the composition including: a resin, a bulk particulate material, and a cement component wherein the cement component is of a composition that does not release or cause the production of free lime, either during or after curing, the method characterised by the steps of a) applying the composition, and b) positioning the construction components correctly with respect to one another.

According to another aspect of the present invention there is provided a method of filing gaps between adjacent construction components using a composition 15 including the additional initial step of: a) applying a base material first to at least one of the construction components.

In a preferred embodiment the construction components may be roof tiles.

In a preferred embodiment the composition of the present invention may be used 20 for bedding and/or pointing concrete, clay or terracotta roof tiles, and shall be referred to as such herein. 9 However, this use should not be seen as limiting as the composition of the present invention could also be utilised for other purposes and construction means, for example to fill in gaps in a wall or between other construction components.

In one embodiment the composition may be used for both bedding and pointing functions in a one step process. In this instance the composition of the present invention will be used as both the bedding and pointing components.

However, in particularly preferred embodiments the composition of the present invention may be used as a pointing compound for roofs which have already 10 been bedded with traditional concrete bedding mortar.

Throughout this specification the term 'cure' or 'curing' should be taken to mean the reaction occurring between a liquid and the cement component which hydrates the cement component and leads to the cement component bonding the components in the composition together and hardening to a cohesive mass. 15 This term has been used throughout this specification with respect to the reaction undergone by the cement component.

Reference throughout this specification has also been made to the resin setting or drying. This should be taken to mean the removal of a liquid from an emulsified resin which leads to the resin bonding to other components.

The combined curing and setting of the composition includes both the above factors. This may be referred to as curing or setting of the composition interchangeably throughout this specification.

The present invention provides significant advantages over existing compositions in that it has sufficient adhesion to be able to be applied to a wet cement base, 25 while still allowing both the cement base and the composition of the present invention to cure satisfactorily.

Throughout this specification the term resin should be taken as meaning a polymeric non-rigid binder In a preferred embodiment the resin of choice will provide high flexibility, high workability, and high adhesion to the composition.

In a preferred embodiment the chosen resin will have the following characteristics: • it will be able to form a liquid based emulsion or solution, for example water, • a liquid based emulsion or solution made of the resin will be stable in the presence of solubilized metal ions, these are freely generated as cement hydrates. • the resin will be compatible and stable when combined with the other components in the composition • it will be able to set to bind the bulk particulate matter together as a coherent mass once the liquid has been removed, to provide sufficient adhesion and flexibility to resist normal roof movement and stresses without rupture • it will be durable against weather exposure In a preferred embodiment the composition must contain a sufficient amount of resin to provide the required flexibility and adhesion, however if too much resin is added the composition is very wet and sloppy and takes a considerable time longer to cure or set. 11 In a preferred embodiment the composition may contain between substantially 6 and 18 percent resin (expressed as the volume of the resin solids of the mixture).

A resin content of below 6 % results in the composition being too brittle.

A resin content of above 18 % results in the composition being prohibitively slow 5 to cure or set, and expensive.

In a particularly preferred embodiment the composition may contain substantially 12 % resin.

Two of the main problems with existing compositions used for bedding and pointing are that they crack easily and that they have to be applied to a dry bedding material.

The high resin content of the current application means that the composition has enough flexibility to be able to move with any shifting of the roof structure, thereby preventing cracking or flaking of the composition once cured.

In a preferred embodiment the resin may have sufficient adhesion to be able to be applied onto a wet surface or base.

The high resin content provides sufficient adhesion to allow the composition to be applied while wet onto a base of wet material such as bedding water or cement. This has the significant advantage that the job can be completed in one go, rather than applying a bedding component, waiting for this to cure and then coming back to apply the pointing component.

A further significant advantage of the composition of the present invention is that it is able to be applied to either a wet or dry base material in variable weather conditions. 12 Throughout this specification the term 'variable weather conditions' should be taken to include conditions under which it is not possible to apply a standard existing cement based product. Variable weather conditions may include conditions which are damp, or when raining.

This characteristic of the composition of the present invention significant!y increases its versatility and usability. It also overcomes significant problems with existing products which prevents there use in adverse (variable) weather conditions, such as lack of, or incomplete curing.

The capability of the composition of the present invention to be applied and/or to 10 cure in wet or variable weather conditions is due to its adhesive nature and increased water resistance.

A further significant advantage of the present invention is that the composition is able to cure sufficient in variable weather conditions. This means that if the composition is applied, unlike existing cement based components it is still 15 capable of curing sufficient if the weather changes, for example it rains.

The combined ability of the composition of the present invention to be applied and to cure in variable weather conditions significantly enhances the ability of builders or roofers to complete jobs on time, and at one time, without having to make multiple trips to the building site to ensure the work is undertaken in the 20 right weather conditions, and that the base (bedding) material has completely cured prior to applying the pointing compound.

According to another aspect of the present invention there is provided a composition substantially as described above wherein the composition has increased water resistance. 13 The increased water resistance is believed by the applicant to be due to the positive curing via a cement reaction while still having the advantage of preventing efflorescence.

Throughout this specification the term wet shall be taken as meaning not hard set or cured. Before the composition is hard set it may be easily penetrated by a sharp object such as a nail or knifeblade.

In a preferred embodiment the resin may be a styrene-acrylic resin.

However, this should not be seen as limiting as other resins may also be utilized with the present invention, including acrylic, styrene-butadiene, vinyl acrylic, vinyl acetate resins to name a few. Other resin families such as 'alkyd' may also be used as long as the required characteristics are met.

In one particularly preferred embodiment the resin may be Resin 422 supplied by Acquos.

In the present invention the bulk particulate material makes up a high percentage of the bulk of the composition.

In a preferred embodiment the bulk particulate material may be a cheap and inert filler substance.

In a preferred embodiment the bulk particulate material may be sand, and shall be referred to as such herein.

In a preferred embodiment the sand may have a particle size such that it allows the composition to be easily worked and smoothed.

In a preferred embodiment the composition may contain between substantially 50 to 80 % (by volume) bulk particulate material (inert filler). 14 When less than 50 % of the composition is bulk particulate matter the composition is too wet.

When more than 80 % of the composition is bulk particulate matter the composition is too thick, and is not easily worked.

In a particularly preferred embodiment the composition may contain between substantially 63 % bulk particulate material.

Throughout this specification the term cement shall be taken as any material which binds any loose sediment or other components into a coherent mass.

In the present invention the cement component is one which does not release or 10 cause the production of free lime during or after curing.

In a preferred embodiment the cement component acts as a hydraulic binder.

In a preferred embodiment the cement component may be a calcium-aluminate cement, and shall be referred to as such herein.

The preferred amount of cement component is herein expressed as a ratio by 15 weight to the amount of dry resin binder.

In a preferred embodiment the composition may contain a cement component of between substantially 0.5 to 4.0 times the weight of the dry resin amount.

At a cement component amount lower than 0.5 times the weight of dry resin the curing of the composition is decreased.

At a cement component amount above 4.0 times the weight of dry resin the composition is too brittle.

In a particularly preferred embodiment the cement component amount of the composition may be substantially 1.5 times the dry weight of resin.

Existing pointing compounds containing resin are water based. Therefore if they are very thickly applied, such as at a thickness greater than 5 mm as per the 5 manufacturer's guarantee the resin will not set. This is due to the difficulty in releasing liquid such as water from the composition.

The cement component present in the composition of the present invention acts to overcome the above problem, and draws the liquid such as water out of the resin, allowing the resin to set/cure. This provides quick curing of the 10 composition. It also allows the composition to rapidly cure when the composition has been very thickly applied. This overcomes the major disadvantage of previous pointing compositions which have to be applied in a very accurate, thin (i.e. 5 mm) and even manner to provide adequate curing of the compound.

The composition of the present invention may be applied at thicknesses up to 15 substantially 100 mm.

This is a significant advantage over existing products which cannot be applied in thicknesses over 5 mm, due to lack of, or uneven curing.

The cement component used in the present invention or other pointing compounds may be ordinary Portland cement. The use of Portland cement 20 however leads to a number of significant disadvantages, including the following: • Portland cement is very slow to cure, and • More of a problem, Portland cements releases lime in the presence of water. This phenomenon is termed efflorescence. 16 Efflorescence is highly undesirable as it causes unsightly white lime deposits over the area in question. This is both unsightly and weakens the cement from which the lime leaches therefore leading to increased maintenance.

Calcium aluminate cement components, the cement component preferably used 5 in the composition of the present invention cures via a different method from normal Portland cement.

As a cement component with a high alumina content cures it forms calcium aluminate compounds, which do not lead to the generation of free lime.

The use of calcium aluminate cement component in the composition of the present invention overcomes the major problem of efflorescence.

In a preferred embodiment the cement component may be Ciment Fondu©. However, this should not be seen as limiting as other calcium aluminate cements may be utilized with the present invention.

In a preferred embodiment the ratio of the four main components in the final composition, being resin, bulk particulate material, a cement hydraulic binder component, and a liquid may be substantially: 12 (resin):63 (bulk particulate material):6 (cement): 16 (liquid) (ratio of overall volume in the final formulation).

In a preferred embodiment the composition may be manufactured by a two step process wherein a wet and dry formulation are prepared, which are then mixed together to form the final composition, this is the process which will be referred to herein.

In a preferred embodiment the wet formulation may be prepared by mixing the resin in a liquid to form an emulsion. Throughout this specification this mixture shall be termed the wet formulation. 17 In a preferred embodiment the liquid may be water, and shall be referred to as such herein. However, this should not be seen as limiting as other liquids may be used, for example organic solvents.

Water has many benefits over other solvents. For example, organic solvents are 5 difficult to work with, they are messy, flammable, and also expensive.

There is currently a pointing product on the market which makes use of linseed oil. Again, this is very messy and hard to work with, a further disadvantage with using linseed oil is that it becomes very brittle after a number of years due to high UV exposure.

In a preferred embodiment the final composition may contain substantially 10 to 30 % water by volume In a particularly preferred embodiment the final composition may contain a water content of substantially 16 %.

In a preferred embodiment the volume ratio of the four main components in the 15 final composition, being resin, sand (bulk particulate material), a cement component, and water may be substantially 12:63:6:16.

In a preferred embodiment the dry formulation may be prepared by mixing the bulk particulate material (sand), and the cement component. Throughout this specification this mixture shall be termed the dry formulation.

The wet and dry formulations may then be mixed together to form the final composition of the present invention.

Alternatively, all the 'dry' components (all components other than the liquid) may be mixed together. Liquid (water) can then be added to the dry mixture on-site. This way of manufacturing the composition has the advantage that it reduces the 18 weight and bulk of the product as water is usually freely available on building sites. In further alternative embodiments, different combinations of the wet and dry formulations may be mixed together before mixing of the final product.

In a preferred embodiment the dry formulation of the present invention may also include one, or a combination of one or more of the following components: ■ A hydraulic binder In a preferred embodiment the hydraulic binder may also include a plaster.

In a preferred embodiment the plaster may make up part of the 'hydraulic binder' (cement component).

This substitutes some of the calcium aluminate cement, and may lead to increased ease of workability and decreased cost.

In a preferred embodiment the plaster may be one which acts as a filler, and helps with the covering and smoothness of the composition.

The plaster may also provide a small additional action which helps to withdraw water from the resin thereby allowing the composition to set/cure.

In one preferred embodiment the plaster may make up between substantially 0 and 50 % of the hydraulic binder content (cement component) by weight.

In a preferred embodiment the plaster may be Gypsum plaster, which incorporates crystalline hydrated calcium sulphate. Gypsum plaster is used in making Plaster of Paris, and plaster/plaster board used in the building industry. However, this should not be seen as limiting as other plasters may be utilized with the present invention. 19 A thickener In a preferred embodiment the addition of at least one thickener may increase the workability of the final composition.

In a preferred embodiment the thickener may be a clay.

In one preferred embodiment the clay may be bentonite clay. Bentonite clay is a fairly "sticky" clay, this may therefore also play a small role in providing the sufficient adhesiveness of the final composition. However, this should not be seen as limiting as other clays may be utilized with the present invention.

In another preferred embodiment the thickener may be a mixture of a number of thickeners.

In a preferred embodiment the thickener may be a mixture of bentonite clay Benaqua 4000 and a urethane acrylic type thickener.

In a preferred embodiment the urethane acrylic type thickener may be Rohm & Haas RM5.

These thickening components may contribute to the preferred 'trowel workability' of the final product.

However, they are not crucial to the working of the present invention, and could be replaced with other combinations of thickeners including, but not limited to cellulose ethers or alkali swellable acrylics, such as Viscales HV30.

A cement curing accelerant A cement curing accelerant acts as a catalyst to speed the hydration of the cement component. Hydration of the cement component drives the withdrawal of water from the resin leading to curing of the composition.

In a preferred embodiment lithium carbonate may be used as the cement curing accelerant.

However, this should not be seen as limiting, as any other cement curing accelerants may be utilized with the present invention, such as calcium chloride.

A cement curing retardant A cement curing retardant acts to slow the hydration of the cement component.

In a preferred embodiment sodium citrate may be used as the cement curing retardant.

However, this should not be seen as limiting as any other known cement curing retardants may be used, for example ordinary sugar.

In a particularly preferred embodiment a combination of a cement curing accelerant (for example lithium carbonate) and a cement curing retardant (for example sodium citrate) may be utilized in the composition of the present invention.

The combination of cement curing accelerant and retardant may provide a consistent and reliable hydration of the cement component, and therefore curing of the composition. 21 This combination allows the working time of the composition to be more finely controlled.

Without the addition of cement curing accelerants and retardants, the composition will cure quite quickly, but this may be in an unpredictable manner, which is undesirable.

In a preferred embodiment the amount of lithium carbonate and sodium citrate may be such that it provides the same rate of curing as without these components however it is more reliable and not so reliant on the weather or temperature.

However, this should not be seen as limiting as the ratios of lithium carbonate and sodium citrate may be altered to provide either a faster or slower curing rate.

Fibre In some embodiments the fiber may increase the workability of the composition and may also provide a degree of fine crack persistence.

In a preferred embodiment the fiber may be cellulose fiber. Cellulose fiber is able to be used in conjunction with the present invention as the higher alumina content cement component has a neutral pH, unlike normal cement mixers.

In a preferred embodiment the wet formulation of the present invention may also include one, or a combination of one or more of the following components: A surfactant 22 In a preferred embodiment a surfactant may be added if the composition is going to be pre-coloured via the addition of a coloured pigment.

In a preferred embodiment the surfactant acts as a dispersion agent for a colouring agent, which may or may not be added to the mixture to produce a final coloured composition. The surfactant improves the colour development of the colour pigment.

In a preferred embodiment the surfactant may be Rohm & Haas Oratan 731. However this should not be seen as limiting as any other surfactant with the required properties may be utilized, for example Bevaloid 226.

A coloured pigment In some embodiments a coloured pigment may be added to produce a particular colour in the final product. A coloured pigment may be desired to be included so that the composition when used as a pointing compound is a similar, the same, or a contrasting colour to the colour of the roof tiles.

For example for a red colouration a red oxide pigment may be utilized. For other colours different pigments or combinations of pigments may be utilized. These would be well known to one skilled in the art.

A defoamer When resin and water are mixed, it is a common phenomenon that foaming occurs, this an undesirable effect during manufacture as it may lead to inconsistent mixing or separation of the components. Therefore it is beneficial for the manufacturing process if a defoaming component is present to stop this occurring. 23 In a preferred embodiment the defoamer may be any defoamer which has the required properties, for example Bevaloid 681 or Foamaster NXZ..

• A thickener In a preferred embodiment a thickener may be added to ensure the correct consistency of the final composition.

A thickener may be added to the wet formulation, instead of, or in addition to the thickener, preferably benonite clay thickener which may be added to the 'dry' formulation.

In a preferred embodiment the final composition requires a consistency which is easy to apply and stays in place but is still easily molded or smoothed.

In a preferred embodiment the thickener added to the wet formulation may be Rohm & Haas RM5.

However the specific thickener added to the wet formulation is not crucial to the working of the present invention, and could be replaced with other combinations of thickeners including, but not limited to cellulose ethers or urethane acrylics. For example Viscales HV30.

In a preferred embodiment a combination of RM5 and bentonite clay may be used to provide the required consistency. However, this should not be seen as limiting as one or the other may be used independently, or in conjunction with a different thickener.

Advantages of the present invention over existing products include the following: 24 It can be applied when wet to a wet cement base, this decreases or eliminates the time required to allow a bedding compound to cure before the pointing compound is applied, The present composition may be used as either just a pointing compound, or as both the bedding and pointing compound in a one step process, The composition contains a high proportion of resin which provides greater flexibility, workability and adhesion, The composition contains a calcium aluminate cement which draws the water out of the resin, allowing the composition to be applied in varying or thick layers while still ensuring quick and complete curing, The high alumina content prevents efflorescence, a common problem when normal cements are used, The composition has a significantly greater resistant to UV irradiation, resulting in longer lasting roofs and decreasing the cracking of the compound, The composition may be applied in variable weather conditions such as drizzle, or even rain and still cure completely. Traditional products can not be used in adverse weather conditions. This increases the available work time, especially during winter months when weather conditions are often not optimal.

Due to the increased thickness in which the composition can be applied, the quick curing time, and the ability to apply in an increased range of weather conditions, the job can be completed in one visit to the site. This decreases labor requirements, costs and time required to get the job finished.

BRIEF DESCRIPTION OF DRAWINGS Further aspects of the present invention will become apparent from the ensuing description which is given by way of example only and with reference to the accompanying drawings in which: Figure 1 shows a schematic of the weight pull test used to compare the composition of the present invention with existing compounds.

BEST MODES FOR CARRYING OUT THE INVENTION One particularly preferred embodiment of the present invention has the composition and amounts of components in proportion to each other as shown in Table 1 and 2 for the dry and wet formulations respectively.

Table 1: Composition and amounts of components in the dry formulation: Dry Formulation Amount Calcium aluminate cement 0.700 Sand 8.932 Plaster 0.350 A thickener (Benonite clay) 0.010 A cement curing accelerant (Lithium carbonate) 0.006 A cement curing retardant (Sodium citrate) 0.002 Total .00 26 Table 2: Composition and amounts of components in the wet formulation: Wet Formulation Amount Water 0.348 Resin 1.199 Surfactant 0.012 Defoamer 0.005 Coloured pigment 0.218 Thickener (RM5) 0.018 Total 1.800 The dry formulation is prepared by mixing the required ratios of each component together to form a consistent mix.

The wet formulation is prepared by mixing together the components in the wet formulation in the required amounts.

The overall composition is formed by mixing together the wet and dry formulations to form a consistent composition with the required properties.

The applicants have found that if the composition is stored undercover at less 10 then 35 °C then it has a minimum shelf life of six months if unopened.

The composition may then be used as a bedding and pointing composition for concrete, clay or terracotta tile roofs.

In one embodiment the composition may be used for both functions in a one step process where the composition is used for both bedding and pointing.

However preferably the composition of the present invention is used is a pointing compound for roofs which have already been bedded with traditional concrete bedding mortar. The present invention has sufficient adhesion to be able to be 27 applied to a wet cement base.

Due to the high resin content the composition is very flexible and the presence of the calcium aluminate cement which acts to draw water out of the composition or resin means that the composition may be applied in either a thin or very thick 5 layer. The composition of the present invention may be applied in a layer up to 100 mm thick.

The consistency of the present composition also allows easy moulding or smoothing of the finished edge resulting in a nice finish.

A number of tile bonding tests have been undertaken by the applicant to 10 compare the composition of the present invention with three existing bedding and /or pointing compounds.

Tile Bonding Testing - methodology The aim of the testing undertaken was to compare the adhesive properties of 15 various existing, commercial available, flexible ridge bonding compounds to the composition of the present invention, herein after referred to as "Ridge it".

Samples were prepared of 70mm X 70 mm pieces of "Monier" ridge capping adhered with 5mm thick bonding compound both to "Monier" tile surface, and to a glass surface.

The tile surface samples were aged according to the following treatments: For the "Monier" tile surface: 1. 12 hours at a temperature of 45 °C, followed by 72 hours of air drying, 2. 12 hours at a temperature of 45 °C, followed by 88 hours of air drying, 28 and 3. 12 hours at a temperature of 45 °C, followed by 120 hours of air drying For the glass surface: 4. 12 hours at a temperature of 45 °C, followed by 72 hours of air drying.

The samples were then progressively weight pull tested as shown in Figure 1.

Figure 1 shows the tile (or glass surface) (1) positioned and held in a vice (2). The product (3) is applied to the tile (1). To the product is then attached a ridge tile or capping (4). The ridge tile (4) has a nut (5) epoxy glued to the ridge (4) top face as an attachment point for the pulley cable (6) positioned around two 10 pulleys (8) and (9). A weight (7) is then applied to the pulley cable (6).

The first test was undertaken "dry" i.e. the samples were tested "as is" after the initial aging treatment 1 (12 hours at a temperature of 45 °C, followed by 72 hours of air drying). The maximum weight used in this test was 20.8 kg.

Table 3: Results of pull test for ageing treatment 1 - Dry conditions DURABOND RIDGE IT POINT WORKS FLEXI POINT STILL ON STILL ON OFF OFF .8 kg .8-kg 13.9 kg Still soft in centre 13.9 kg Still soft in centre The first row in Table 3 provides the name of the compound tested.

The second row provides details of whether the ridge tile or capping was still attached to the tile (or glass) surface after the test.

The third row shows the maximum weight which was held by the compound (note 29 maximum weight of 20.8 Kg), and any observations noted.

As can be seen in Table 3, both Pointworks & Flexipoint compounds both failed cohesively at the weight loads shown.

As neither Durabond nor Ridgelt failed at the maximum weight used, these samples were retested 2 days later with heavier weight still as shown in Table 4, this was equivalent to using aging treatment 3 above (12 hours at a temperature of 45 °C, followed by 120 hours of air drying). The maximum weight used being 35.7 Kg.

Table 4: Results of pull test for ageing treatment 3 - Dry conditions DURABOND RIDGE IT PULLED NUT OF RIDGE PULLED NUT OF RIDGE .7 kg .7 kg There was again no cohesive or adhesive failure of either compound, rather the epoxy glue to the nut adhesion failed in both cases.

The samples were also "wet" tested, that is after initial aging treatment 2 (12 hours at a temperature of 45 °C, followed by 88 hours of air drying) the samples were fully immersed in water for 4 hours immediately prior to testing, again up to a maximum weight of 20.8kg. The results of this test are shown in Figure 5.

Table 5: Table 4: Results of pull test for ageing treatment 2 - Wet conditions DURABOND RIDGE IT POINT WORKS FLEXI POINT STILL ON STILL ON OFF OFF .8 kg .8 kg 6.3 kg 3.1 kg Both Pointworks & Flexipoint showed cohesive failure and at significantly reduced weight load compared to "dry" test.

Neither Durabond nor Ridgelt failed up to the maximum weight used The glass panel samples were age treated as per treatment 4 (12 hours at a temperature of 45 °C, followed by 72 hours of air drying) and were then fully immersed in water for testing. The time taken before the compound failed either cohesively or adhesively to moderate finger pressure noted, these results are shown in Table 6.

Table 6: Underwater test using glass DURABOND RIDGE IT POINTWORKS FLEXI POINT 3 hrs OK 3 hrs OK mins OFF mins OFF 4 hrs OFF 4 hrs OK A little soft in centre but came off glass in 1 piece Can't get it off the glass Soft in centre and crumbled when lifted off glass Soft in centre and crumbled when lifted off glass As can be seen in Table 6 both Pointworks & Flexipoint showed cohesive failure 15 after only 30 minutes.

Both Durabond and Ridgelt were fine after three hours; however Durabond failed after 4 hours. 31 Ridgelt was the only compound which did not fail during testing.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.

Qttk^ ... - 8 2008 R E C Lu r Q 32

Claims (30)

WHAT l/WE CLAIM IS:
1. A composition for filling gaps between adjacent construction components including a resin, of a concentration between substantially 6 and 18% of the composition, expressed as the volume of the resin solids of the composition, a bulk particulate material, of a concentration between substantially 50 to 80% of the composition by volume, a calcium aluminate cement component, at a concentration between substantially 0.5 to 4 times the weight of the dry resin amount, and a liquid, at a concentration of between 10 and 30 % of the composition by volume the composition characterised in that the calcium aluminate cement component is of a composition that does not release or cause the production of free lime, either during or after curing, wherein the composition does not include Ordinary Portland cement or free lime.
2. A composition as claimed in either claim 1 wherein the composition contains substantially 12% resin, expressed as the volume of the resin solids of the composition.
3. A composition as claimed in either claim 1 or 2 wherein the resin is styrene acrylic resin.
4. A composition as claimed in any one of claims 1 to 3 wherein the bulk particulate material is sand.
5. A composition as claimed in any one of claims 1 to 4 wherein the composition includes substantially 63 % bulk particulate material T-1? v
6. 6.
7. 7.
8. 8.
9. 9.
10. 10.
11. 11.
12. 12.
13. 13,
14. 14
15. 15
16. 16 A composition as claimed in any one of claims 1 to 5 wherein the composition includes a cement component of substantially 1.5 times the weight of the dry resin amount. A composition as claimed in any one of claims 1 to 6 wherein the liquid is water. A composition as claimed in any one of claims 1 to 7 wherein the composition includes substantially 16 % liquid, by volume. A composition as claimed in any one of claims 1 to 8 wherein the ratio of resin, bulk particulate material, a cement hydraulic binder component, and a liquid may be substantially: 12 : 63 : 6 : 16, as the ratio of overall volume in the final composition. A composition as claimed in any one of claims 1 to 9 wherein the composition also includes at least one hydraulic binder. A composition as claimed in any one of claims 1 to 10 wherein the composition also includes at least one thickener. A composition as claimed in any one of claims 1 to 11 wherein the composition also includes at least one cement curing accelerant. A composition as claimed in any one of claims 1 to 12 wherein the composition also includes at least one cement curing retardant. A composition as claimed in any one of claims 1 to 13 wherein the composition also includes at least one surfactant. A composition as claimed in any one of claims 1 to 14 wherein the composition also includes at least one coloured pigment. A composition as claimed in any one of claims 1 to 15 wherein the composition also includes at least one defoamer. , <-v©rty Oft - • « j\j 2. - 9 W 2008
17. 17. A method of manufacturing a composition as claimed in any one of claims 1 to 16, the method characterised by the steps of a) preparing a wet formulation by mixing the resin with the liquid, b) preparing a dry formulation by mixing the bulk particulate material and the cement component, c) mixing the wet and dry formulations.
18. 18. A method as claimed in claim 17 wherein the wet and dry formulations have the following formulation: Dry Formulation Amount (kg) Calcium aluminate cement 0.700 Sand 8.932 Plaster 0.350 A thickener (Benonite clay) 0.010 A cement curing accelerant (Lithium carbonate) 0.006 A cement curing retardant (Sodium citrate) 0.002 Total 10.00 Intense OiWvf"' o- M s AH* 2038 1 V E D 35 Wet Formulation Amount (kg) Water 0.348 Resin (66% resin Nett Volume) 1.199 Surfactant 0.012 Defoamer 0.005 Coloured pigment 0.218 Thickener (RM5) 0.018 Total 1.800
19. 19. A method of manufacturing a composition as claimed in any one of claims 1 to 16, the method characterized by the steps of: a) preparing a dry formulation containing the resin, the bulk particulate material and the cement component, b) adding a liquid to the mixture from a).
20. 20. A method of filling gaps between adjacent construction components using a composition, the composition including: a resin, of a concentration between substantially 6 and 18% of the composition, expressed as the volume of the resin solids of the composition, a bulk particulate material, of a concentration between substantially 50 to 80% of the composition by volume, a calcium aluminate cement component, at a concentration between substantially 0.5 to 4 times the weight of the dry resin amount, and a liquid, at a concentration of between 10 and 30 % of the composition by volume 36 Hsu. foperty Office of N.Z. -S A' B 2038 RE'"". ! V f wherein the claium aluminate cement component is of a composition that does not release or cause the production of free lime, either during or after curing, wherein the composition does not include Ordinary Portland cement or free lime, the method characterised by the steps of a) applying the composition, and b) positioning the construction components correctly with respect to one another.
21. 21. A method of filling gaps between adjacent construction components as claimed in claim 20 including the additional initial step of: a) applying a base material first to at least one of the construction components.
22. 22. A method of filling gaps between adjacent construction components as claimed in either claim 20 or 21 wherein the composition is used for pointing roof tiles.
23. 23. A method of filling gaps between adjacent construction components as claimed in either claim 20 or 22 wherein the composition is used as a pointing compound for roof tiles which have been bedded with an existing concrete bedding mortar.
24. 24. A method of filling gaps between adjacent construction components as claimed in any one of claims 20 to 23 wherein the composition is applied to a wet base material.
25. 25. A method of filling gaps between adjacent construction components as claimed in any one of claims 20 to 24 wherein the composition is applied in variable weather conditions. Intellects' Ofl'ce of n z. - 9 Ark 2008 RECEIVED 37
26. 26. A method of filling gaps between adjacent construction components as claimed in any one of claims 20 to 25 wherein the composition is applied at a thickness up to substantially 100mm.
27. 27. A method of filling gaps between adjacent construction components as claimed in any one of claims 20 to 26 wherein the composition is formulated such that it will cure sufficiently in variable weather conditions.
28. 28. A composition substantially as herein described with reference to the accompanying examples.
29. 29. A method of manufacturing a composition substantially as herein described with reference to the accompanying examples.
30. 30. A method of filling gaps between adjacent construction components substantially as herein described with reference to the accompanying examples. Intellect?' a 08 R VED 38