AU2006213933A1 - Decorative coral and sponge - Google Patents

Description

P001 Section 29 Regulation 3.2(2)

AUSTRALIA

Patents Act 1990 COMPLETE

SPECIFICATION

STANDARD

PATENT

Application Number: Lodged: Invention Title: Decorative coral and sponge The following statement is a full description of this invention, including the best method of performing it known to me: DECORATIVE CORAL AND SPONGE FIELD OF THE INVENTION This invention relates to a method of providing decorative coral and sponges. These corals and sponges have been treated to accommodate their use for aesthetic and display purposes, such as in aquariums and various other displays.

BACKGROUND OF THE INVENTION Corals and sponges are used for decorative purposes, such as in visual displays, use in aquariums or as aesthetic features for pot plants or flower arrangements. When corals are used for display or in an aquarium, they can often look bleached and pale. This is typically considered to have the effect of minimising the aesthetic impact or appeal, especially if they have been collected after being washed up on a beach.

Coral and sponge that has washed up and been salvaged from a beach is a limited resource. Hence, extending the service life of the product minimises the amount of coral and sponge that needs to be salvaged or otherwise harvested.

When dead coral, such as that which is washed ashore is used as decoration in a wet or damp environment, such as with a flower arrangement/pot plant or in an aquarium, it usually starts to dissolve and make the water alkaline.

This shift in pH is not desirable, as the pH can shift to the extent that the plants or fish may become unhealthy or even die. The pH shift can be managed, but such management requires monitoring of pH and pH correction to minimize pH shift.

After a period of time of the coral slowly dissolving in such a manner, the coral typically becomes unstable and breaks up or becomes unsightly. In both instances, the coral is then discarded. This naturally requires the replacement of the coral and or sponge in order to maintain the desired aesthetic qualities of the display.

In order to improve the aesthetic impact and appeal of coral and sponges, people have tried to keep the coral and sponges alive. This is not only difficult in practice, but also limits the use of the coral and sponge to a marine aquarium.

Further, the aquarium must be extremely well maintained as corals are one of the more sensitive marine organisms and can be quite difficult to keep alive in an artificial environment. Moreover, the use of live coral requires that the coral be harvested alive from a naturally occurring coral reef. This is a process that has the potential to lead to the creation of significant ecological and environmental problems.

One solution that has been proposed in order to improve the service life of harvested dead coral in an aquarium and for minimising the problem of pH shift, is described in United States Patent 3,955,081. United States Patent 3,955,081 describes the process of "Plastic Coating" the coral. The problem with this technique is that the technique described changes the texture of the coral, which results in the coral appearing artificial. Further, the plastic coating can be peeled off and does not always adhere to the surface of some corals, particularly if the surface is smooth.

SUMMARY OF THE INVENTION In a first aspect of the present invention, there is provided a method of preserving a coral or sponge, the method including the steps of: a) washing the coral or sponge to remove dirt and salt; b) applying a colouring agent; c) impregnating the coral or sponge with a sealer wherein the sealer covers substantially the entire surface of the coral or sponge and wherein the colouring agent is applied in a separate step to application of the sealer.

In a preferred embodiment, the present invention provides a method of preserving a coral or sponge for the purpose of using the coral or sponge in an aesthetic or visual display, the method including the steps of, washing the coral or sponge to remove dirt and salt, shaping the coral or sponge into a desired shape or configuration for aesthetic appeal, coating the coral or sponge with a colouring agent, drying the colouring agent, and impregnating the coral or sponge with sealer, wherein the sealer covers substantially all of the surface of the coral or sponge and wherein the colouring agent is applied in a separate step to the sealer.

Preferably, the colouring agent or sealer can be applied by spraying, soaking or dipping the coral or sponge.

Preferably, the sealer is one part, solvent based, acrylic sealer and the colouring agent is non-toxic water based paint.

Also preferably, when the method of the present invention is used in the preservation of coral or sponge or parts of coral or sponge that are medium to large in size, the coral or sponge is impregnated with a sealer prior to coating with a colouring agent. In preserving coral or sponge that is relatively small in size, it is preferred that the colouring agent be applied prior to impregnation by the sealer.

In another aspect of the present invention there is provided a decorative product, including a coral or sponge coated with paint and substantially sealed by a sealer.

DESCRIPTION OF PREFERRED

EMBODIMENT

The invention will now be described with reference to a preferred embodiment. The invention is particularly applicable to the treatment of coral and sponge that may be used in decorative applications, particularly those applications that are pH sensitive.

Coral or sponge is firstly recovered from the natural environment after it has been washed up on a beach. At this stage, the coral is dead and usually has little natural colour, typically having a bleached, off-white appearance.

The coral or sponge, once recovered, is washed in fresh water and dried.

This washing removes any loose and flaky particles as well as removing any salt from the surface of the coral or sponge to be treated. After washing, most material that would interfere with the bonding of the surface coating has been removed.

Once washed, the sponge needs to be dried relatively quickly to prevent breakdown or general deterioration of the sponge. It is preferable to dry the sponge in less than 24 hours after washing. The coral or sponge is normally spun to remove excess water, then sun dried.

The coral or sponge is then shaped as desired for aesthetic appeal. As coral that has been washed up is part of a larger coral system, the parts washed up are typically of many different sizes and shapes. The coral needs to be shaped so that it has the desired shape of the final product. If the product to be treated is a sponge, the sponge can be moistened and held in the desired shape with wedges or blocks until dried.

If the coral or sponge is a small piece or a collection of small pieces, it is then coloured by dipping, soaking, spraying, brushing or a combination of these.

More than one colour can be applied, and each colour may be applied using a different technique. The colouring agent may be a water based paint. This type of paint has the advantage of being non-toxic so that when the final product is used in an aquarium environment, toxins do not get leached out and contaminate the water in the aquarium.

Following painting, the coral or sponge is dried for a suitable period of time. Typically, this period is a minimum of 2 to 3 hours, but can be up to 3 days.

Larger pieces of coral or sponge are spun dried to remove excess colouring agent prior to being dried.

Once dried, the coral or sponge is coated with a suitable sealer. This sealing coating process may be performed by dipping, pouring, spraying or brushing. If the coral or sponge is to be dipped, the residence time in the sealer is preferably between 1 to 10 seconds. The residence time needs to be controlled, as the colouring may mix with the sealer if the coral or sponge is submerged for an excessive period of time.

The sealing agent used is preferably a one part spirit/solvent based acrylic sealer. This product has advantages of being relatively fluid, so that it does not settle or accumulate in the pores of the coral or sponge, but instead, will drain away. The relatively fluid nature of the sealer helps maintain the surface texture of the coral or sponge by minimising the inconsistencies or bridging of the pores, so that when the sealed coral or sponge is displayed, it has a more natural appearance. One type of sealer that has been found to be suitable for use in the present method is that known as "Enviroshield an acrylic co-polymer in solvent, typically used for sealing clay and concrete paving bricks. However, it should be understood that any such suitable sealer could be used.

In those instances where the coral or sponge is of a size that is relatively large, it has been found that it is more efficacious to first impregnate the coral or sponge with a sealer prior to applying the colouring agent. In this case, the sealer is preferably dried by a suitable means prior to application of the colouring agent.

In drying these larger pieces, it is preferably to also hang the coral or sponge and sun-dry, so that excess sealer can be removed by a dripping action.

Once the coral or sponge has been coloured and sealed, or sealed and coloured, the product is optionally blown with compressed air to ensure that the small pores are not bridged with the sealer. This further helps maintain the natural look of the resulting product.

The sealed coral or sponge is allowed to dry prior to sale or display.

A one part sealer has also been chosen over multipart sealers as the one part sealer keeps a consistent viscosity longer and has a longer pot life when compared to multipart sealers. There is also the advantage that a single part sealer has consistent properties and is not subject to the variations of mixing multi part sealers.

It has also been found that one part sealers are not as affected by the introduction of colouring agents. When using the multipart sealers over the colouring agents, it has been found that the sealer tends to strip the colour from the coral or sponge, or that the colours will bleed and combine with the sealer. In such instances, the sealer does not consistently set properly because of the introduction of the colouring agent into the sealer. Other problems with two part sealers including cracking of the seal, fading of the colours and reaction with the tank water, which often leads to clouding of the coating.

Multi part sealers were also found to release chemicals into the water when placed in an aquarium. This has significant water quality issues and prevents the aquarium being used for fish or other aquatic animals and plants.

Example 1 To test results, products were manufactured using the following techniques, and then placed in a testing tank, measuring 50 x 30 x 30 cm.

Test samples of small pieces of coral and sponge were prepared by preparing coral and sponge samples in accordance with the following procedure: a) washing the coral or sponge in fresh water to remove dirt and salt; b) drying the coral or sponge by spin-drying and then sun-drying; c) shaping for aesthetic appeal, by holding sponges into desired shapes and removing broken or deformed parts; d) coating with a colouring agent, being a water-based paint wherein the colouring agent was applied using any one of a range of techniques including dipping, spraying and brushing and allowing the paint to dry; e) impregnating the coral or sponge with a sealer by dipping the coral or sponge into a container of sealer, or using the technique of spraying or brushing the sealer onto the coral or sponge when finished. The product was then blown with compressed air to remove sealer that had bridged pores and allowed to dry for a minimum of 24 hours. The coral or sponge is normally hung up to be sun dried.

Test samples of larger pieces were prepared by preparing coral and sponge samples in accordance with the following procedure: a) washing the coral or sponge in fresh water to remove dirt and salt; b) drying the coral or sponge by spin-drying and then sun-drying; c) shaping the coral or sponge into a desired shape by holding the coral or sponge in the desired shape until dry and removing broken or deformed parts; d) impregnating the coral or sponge with a sealer by dipping the coral or sponge into a container of sealer, or spraying or brushing the sealer then blowing with compressed air to remove sealer that had bridged pores; e) allowing the sealer to dry for a minimum of 24 hours; f) coating the coral or sponge with a colouring agent, being a waterbased paint, by any suitable technique such as dipping, spraying and brushing and allowing the paint to dry.

Testing of the resulting sealed product was conducted by using the following procedure: 1. a tank was filed with tap water; 2. the pH was altered using standard aquarium chemicals to pH 6.8 7.2; 3. the sealed product was introduced into the aquarium; 4. after one week the pH was tested; after one month with no pH modifications the pH was again tested; 6. after 6 months of stable pH fish were introduced and pH changes were monitored.

A range of products were applied to coral and sponge samples and tested in accordance with the above procedures. It was found that the one part acrylic solvent based sealer and water based paint agent produced a product that had a number of desirable properties, wherein: 1. the pH of the water was not significantly affected; 2. the product held its colour for an extended period; 3. the product did not leach toxic chemicals into the tank; 4. the sealer set consistently; when submerged, the sponges became pliable and looked more natural than the other products tested; 6. the coating remained clear and did not become cloudy, even after being submerged for an extended period of time.

The above testing procedure was applied to samples of coral and sponge using a range of paints and sealers. The samples manufactured using non toxic water based paint and a one part solvent based acrylic sealer, produced products that, when introduced to aquariums, did not significantly alter the pH.

Further, testing the pH over a period of time showed that introducing products made with the acrylic paint and one part solvent based acrylic sealer to an aquarium did not shift the pH outside the range acceptable to fish in an aquarium environment.

A number of other products tried resulted in unstable pH, peeling of the coating and/or cloudiness of the coating. The high organic solvent concentration of some of the two part sealers led to contamination of the aquarium, making it generally unsuitable for fish or other aquatic life forms.

A number of samples were prepared in accordance with the above method and exposed to sunlight for an extended period of time. It was found that the water based paint and one part solvent based acrylic sealer combination resulted in products that had a greater resistance to fading for an extended period of time when compared to other tested colouring agents and sealers.

The single part sealer and water based paint yielded the following results from the above test program: initial pH 6.8 7.2, pH 24 hours after introducing sample 6.8 7.2, pH 168 hours after introducing sample 7.0 7.4, pH one month after introducing sample 7.0 7.4, colour fastness after in excess of 6 months was good.

During extensive testing of the product, it was found that applying the coloured paint and the sealer in separate steps has several advantages over applying them as a mixture. This is regardless of whether the sealer is applied first or second, provided each of the paint and sealer is allowed to adequately dry before application of the sealer or paint respectively. The paint, if mixed with the sealer, sometimes changes the characteristics of the sealer such that it no longer adequately seals the coral or sponge. It was thus determined that the one part sealer was superior to the two part sealers for this application for the reasons identified above.

Further, applying the water based paint to the coral or sponge in a step separate to and prior to sealing, regardless of the relative order, allows a number of colours to be applied to the surface so that the final product more closely resembles the look of natural coral. The ability to apply a variety of colours to the coral or sponge can allow for the creation of a more sophisticated and hence lifelike product.

The use of the one part solvent-based acrylic sealer has been found to provide further advantages. The sealer is quite fluid so that it runs out of the pores after application. This limits the number of pores that are filled or partially filled with sealant and assists in maintaining the natural texture of the coral or sponge.

Even further, the one part sealer typically "goes off"' or sets in a predictable manner, and is more consistent and predictable than two part sealers that are subject to the added variation of being a mixed product.

The preferred one part sealer maintains some flexibility after application, so that upon application to a sponge, the sponge is still flexible and the sealer does not crack or peel upon the sponge being flexed.

Claims (13)

1. A method of preserving a coral or sponge including the steps of: a) washing the coral or sponge to remove dirt and salt; b) applying a colouring agent; and c) impregnating the coral or sponge with sealer wherein the sealer covers substantially the entire surface of the coral or sponge and wherein the colouring agent is applied in a separate step to the application of sealer.

2. The method of claim 1, wherein the sealer is applied to the coral or sponge and allowed to dry, prior to coating with a colouring agent.

3. The method of claim 1 or 2, wherein the sealer is applied by spraying.

4. The method of claim 1 or 2, wherein the sealer is applied by soaking or dripping.

The method of any one of claims 1 to 4, wherein the sealer is one part, solvent based, acrylic sealer.

6. The method of any one of claims 1 to 5, wherein the colouring agent is non-toxic water based paint.

7. The method of any one of claims 1 to 6, wherein the colouring agent is applied by one or more methods of dipping, brushing or spraying.

8. The method of any one of claims 2 to 7, wherein the sealer is allowed to dry prior to application of the colouring agent.

9. The method of any one of the preceding claims, wherein the coral or sponge is blown with compressed air after application of the sealer.

The method of any one of the preceding claims, wherein two or more colouring agents are applied.

11. A coral or sponge preserved by the process of any one of the preceding claims.

12. A method of preserving a coral or sponge as hereinbefore described with reference to the accompanying description and examples.

13. A coral or sponge product as hereinbefore described with reference to the accompanying description and examples. DATED this 12th day of September 2006 WATERMARK PATENT TRADE MARK ATTORNEYS P26112AUP1