METHOD FOR PRESERVING AN ORGANIC MATERIAL, USE OF A MINERAL MATERIAL FOR SUCH PRESERVING, AND A KIT FOR SUCH PRESERVING

Abstract: Method for preserving an organic material, in particular a plant or a part of a plant, by keeping the organic material under drying conditions, such as heating, in contact with a microporous, grainy mineral material having a large internal surface and a high water absorbing capacity, and when the organic material is dry, the contact is interrupted, optionally after a certain standing, and the organic material is post-treated by protecting the surface thereof against air. The use of a microporous grainy mineral material having a large internal surface and a high water absorbing capacity, in a composition for preserving an organic material.

Description: METHOD FOR PRESERVING AN ORGANIC MATERIAL, USE OF A MINERAL MATERIAL FOR SUCH PRESERVING, AND A KIT FOR SUCH PRESERVING This invention relates to a method for preserving an organic material, a kit for such preserving and the use of a further defined composition of refractory material for preserving organic materials. The organic material in question is particularly a plant or a part of a plant such as leaves and flowers/petal/stem. For a long time there have existed several types of compositions for preserving plants. Such compositions have generally been based on copper sulfate anhydride in powder form (toxic) or on silica gel with added different amounts of moisture indicator (particularly cobalt) , which are compositions that upon heating (dehydration/reactivation) give off gases and very strong odour which have an irritating effect on the mucous membrane in nose and throat. The commonly used moisture indicator is also toxic. The known compositions are in more or less finely granulated form. In use the plant or the plant part is covered with the composition in question and is kept covered for a period of some days up to several weeks, whereafter the plant or the plant part is taken out. The powder compositions absorb water from the plant/plant part. When copper sulfate anhydride is used in powder form, it dries as a hydrate. Only a limited number of plant species are suitable for this type of preserving, and the appearance of the plants will be of a rather varying quality. Shrinking and poor durability of colors are particularly dominating features. Wood powder/saw dust has also been tried and then in connection with heating in a microwave oven. However, it was found that the wood powder absorbed too much of the energy in a microwave oven, not only to cause damage to the plants, but also to such an extent that there was a risk of fire. There are certain advantages connected with having the material to be preserved buried in a powder material which is subjected to heating. In particular it will be advantageous to use a microwave oven, since a very rapid process is then attained. The disadvantage is that one has to be more careful with respect to treatment time and temperature in order to avoid damages. We have tried several different materials as compositions for preserving organic materials. One of the materials used is ordinary foundry sand, but this sand is of too uneven quality to be satisfactory, and in addition there will frequently remain a layer of dust on the treated organic material. It would be desirable to find a composition which with the same advantage could be used in different drying methods, in particular such methods in which the organic material in buried condition is subjected to varying drying conditions. These conditions may as mentioned be obtained by heating in a microwave oven, and also in an ordinary oven or just by resting at room temperature. An airing cupboard may also be possible to use in connection with the granulate, to make possible professional drying of large amounts of flowers at the same time. It is desirable to find a composition which may be I used as a drying agent under different conditions, without the drying conditions being critical. According to our previous application 93.0971 there is provided a compositon for preserving organic materials, and the composition is a fine grained mixture comprising 45 - 65 volume% of olivine sand and 35 - 55 volume% of crystalline aluminum silicate. In particular it is preferred that said composition comprises 58 - 62 volume! of olivine sand and 38 - 42 volume! of crystaline aluminum silicate. The composition according to 93.0971 has the properties that are necessary so that it may be satisfactory in use. Thus, it may be reactivated, it is insoluble in water, it is not toxic or harmful for the user, it may be heated and dehydrated without giving off irritating gases or unpleasant odour, no chemical reaction takes place between the individual components of the compositions under any part of the use, and it has a granule form which does not leave any pressure marks on the organic material. However, said composition is somewhat heavier than might be desirable, both with respect to shipment/transpor¬ tation and load on the organic material in use. Thus, olivine has a specific gravity of about 3.2 g/cm 3 , and the olivine sand used has a bulk density of about 1.6 - 1.9 g/cm 3 , while aluminium silicate has a specific gravity of about 2.6 g/cm 3 , and the granulate used has a bulk density of about 1.3 - 1.6 g/cm 3 . In addition said composition is relatively expensive. It would be desirable to find a composition with the same good properties as the composition according to 93.0971, but which is lighter and cheaper. A material having these desired properties is a micro¬ porous mineral granular material with a large internal surface and high water absorbing capacity, and according to the present invention such a mineral material is used as a composition for preserving organic materials. The grain size of the mineral material is suitably in the range 0.1 - 1.0 mm, in particular 0.4 - 0.8 mm. The bulk density is not of decisive importance, but as mentioned above it is favourable that it is relatively low, for instance in the range 0.4 - 0.7 g/cm 3 . The microporous character and the large internal surface of the material used appears from its high water absorbing capacity. The mineral material should have a water absorbing capacity of at least 50%, preferably 100% of its own weight. A suitable material is for instance heat treated clay which has been crushed to a powder and optionally granulated. Moler clay is particularly suitable, and other materi¬ als include i.a. diatomaceous earth. A suitable material is available under the trade mark "Absodan Moler FC 25/50", where the last two figures stand for the "mesh" value and represent the grain size in the range 0.3 - 0.7 mm. This material is reported to have a bulk density of 0.546 g/cm 3 and a water absorption of 126%. The mineral material described above is used alone or as a major component in"*a mixture, as a composition for preserving organic materials. Normally it is advantageous to keep the amount of other substances as low as possible in order to avoid separation during transportation and storage. Relevant additives to the above described mineral material are moisture indicators for monitoring the regeneration of the composition after use, or temperature indicators, which in most cases may serve the same purpose. The grain size of the composition must be so small that no pressure marks are formed on the treated organic material, and at the same time the grain size must be so large that the composition is not dusty. Further, the type of organic material and the type of treatment used will also determine the most suitable grain size. The compositon should be as dry as possible when packed, and it should also be kept dry and optionally dried before use. The method for preserving an organic material comprises bringing organic material in contact with the composition under drying conditions. The "drying conditions" may comprise a more or less intensive heating, or it may even comprise standing at room temperature. The "drying conditions" are not necessarily such conditions which would normally be termed as "drying", but such conditions where the organic material dries in contact with the composition used according to the invention. With respect to time it will of course be favorable to perform the drying under relatively strong heating. However, the time will be more critical under strong heating than under mild heating or no heating at all. The suitable drying time will in each case be dependent on the drying method, temperature, exact formula of the composition and the type of organic material. When carrying out the method in a large scale, for instance industrially, it will be easy to find suitable working parameters. When performing the methods in a smaller scale, particularly on private basis, it will be necessary to study the direction for use in order to find the suitable conditions, parti¬ cularly with respect to drying methods, temperature and time. When the method is performed on a private basis, use will normally be made of those means which are generally available at home. These may suitably be grouped as follows: 1) Drying in a microwave oven, 2) drying in a normal oven, 3) drying at room temperature, including mild heating, 4) drying in an airing cupboard. With the four said drying methods using more or less vigorous heating the organic material is first buried in the composition according to the invention. This burying suitably takes place by first placing a layer of the pre¬ sent composition, for instance with a thickness of 1 - 3 cm, in a container, whereafter the organic material is carefully placed on the top of the bottom layer, and more of the present composition is spread over and around the organic material, care being taken to ensure that all voids inside and underneath the material are filled by the pre¬ sent composition. It is then taken into consideration that ' the organic material during the drying process will be fixed in the position which it has in buried condition. If the drying is to take place in a microwave oven, the container used must be of such a material that it stands microwaves and to a considerable extent let these through. The container may for instance consist of plastics, refractory and ceramics, and if the composition is sold in a box, it may also be possible to use said box for the composition used according to the invention. If the drying shall take place in an ordinary oven, the container used must stand heating to a high tempera¬ ture, at least 90 - 100°C. It may for instance be possible to use a large pan, but other types of containers may also be used, particularly fire proof dishes and similar containers. Usually the temperature should at no stage exceed 80"C. With drying alternative 3), long time drying at a warm place, the container may consist of the material which is found most suitable. The container may suitably be placed on a heated floor, over a hot water tank, on a window board, over an electric radiator or in a well heated room, for instance in the sun. If put away in a cold place, no drying will take place, and the flower will be damaged. All methods require a certain amount of energy. As mentioned above it will usually be necessary to try and fail in order to find the proper working parameters in each case. For drying in a microwave oven one will suitably set the oven at low setting (thawing) and then try with a certain time, for instance about 10 minutes. It has been found particularly suitable to repeat the drying with radiation after a resting period with the oven turned off. The radiation period before and after the resting period are suitably of approximately the same length. If it is found that after drying in a microwave oven for a certain time the organic material has become too dry, the process may be repeated with a somewhat shorter treatment time. Correspondingly it is possible to extend the treatment time if it is found that the organic material is too soft and moist. When a suitable time has been found, this may be used directly for other organic materials independant of the type (but with the same setting of the oven) . The time which has then been found, which may be considered as specific for the oven in question, may then for instance be called the specific radiation time of the oven. The drying time for a completely wet, but not dripping wet, ordinary tea bag gives a very good indication of the specific radiation time for a certain type of oven. If this drying takes place in for instance 10 minutes, drying of the plant in the microwave oven will preferably be as follows - 10 minutes radiation - 20 minutes rest in the microwave oven which has been turned off - 10 minutes radiation. These times vary somewhat, for instance depending on the setting of the oven. Normally the drying time (radiation) will be in the range of 5 - 15 minutes and the resting period 10 - 30, preferably 15 - 25 minutes. If the user is treating a very difficult flower, or if he/she wants an extremely good result in the microwave, one may do as follows: Radiation - the mentioned specific time. Rest for 15 - 20 minutes. Radiation period 2 comprises several sequences of one minute radiation and then 10 minutes rest. No rest after the last radiation is necessary. A plastic indicator tab is also available, which is put on top of the granulate when treating a flower in the microwave. The tab changes colour totally when the specific time has passed. The tab adapts to the effect level of the oven in question, and also to the effect setting of the specific oven. It makes the procedure very simple to perform. With drying in an ordinary oven a temperature of 50 - 70°C will normally be used for at least 5 hours. Here, there are rather wide tolerance limits with respect to temperature and time, and it is also unnecessary with any resting period after drying. With long time drying at a warm place the closed container with the organic material buried therein should be allowed to rest for several days, normally for at least 5 days and normally up to 10 days. After this time the organic material is taken out of the container after the compositon has been removed. Drying flowers in an airing cupboard should normally take place as follows: The containers may be open pasteboard boxes. Set the temperature to 50-70°C, and let the dryer work for at least 5 hours. Let it rest over night, and start the cupboard once again, using the same temperature and time. Uncover the plants. The method requires no reactivation, and gives breathtaking results. The method is very suitable for professional dryers. It is also possible to carry out the drying with relatively simple special equipment, such as a vacuum desiccator connected to a water jet pump. A very gentle treatment is then accomplished. After the organic material has been treated as described above, it is suitable to protect it against the air, and such a protection may be obtained by spraying the treated organic material with for instance a silicone spray, or it may be submerged in a plant wax which makes the plant unnaturally stiff and shining so that it is primarily suitable for mounting of many plants in a decoration. Further the organic material may be sprayed with different special compositions for plant protection. It is also possible to place the finished organic material in a plastic composition which will then cure. The cured matrix may be rubbed an polished. Such a product is suitable for instruction purposes and studies since it is of course very robust. Thus, according to the invention there is provided a kit for preserving organic materials, the kit consisting of a first package consisting primarily of a microporous mineral grain material with a high internal surface and high water absorbing capacity, and a second package with a coating agent. An indicator tab may also be a part of the kit. The coating agent used may be any of those mentioned above. The organic material will normally be a plant or a part of a plant, but it is also possible to preserve animal objects after putting them away, for instance insects. The best results are generally contained with relatively thin plant parts. As mentioned above the composition should be fine grained, for instance corresponding to fine table salt. In addition to leaving pressure imprints on the organic material, a too coarse grain size may also have as a consequence that a too low absorption of moisture is obtained. Such a composition will bee free flowing even after it has taken up moisture, and this property may suitably be made use of when the organic material is to be taken out after the heat treatment. It may then be suitable to use a container which in the bottom is provided with an opening closed with a stopper which will be removed from the underside. When this stopper is removed, the fine grained composition will to a great extent flow away, and the organic material may be set free essentially without being touched. With such a gentle removal the chances are minor for damages to occur on the treated organic material. The mineral material used as drying compositions in the following examples was the "Abodan" Moler FC 25/50. Example 1 The flower to be preserved was buried as described above and placed in a microwave oven where the radiation time was 9 minutes, then rest for 20 minutes with the oven turned off and new radiation for 9 minutes. The container with the buried plant was taken out of the microwave oven and was allowed to rest for 2 hours, whereafter the mineral composition was carefully removed and the flower was sprayed with liquid dimethyl polysiloxane. The resulting product had the natural appearance of a flower. Example 2 A lily was buried as described above. The microwave oven was set on "middle effect" and started, after an indicator tab had been placed on top of the granulate. The tab changed colour totally after a treatment of 4 minutes. The container was left to rest for 15 minutes. Then four periods, each consisting of one minute radiation and 10 minutes rest in the oven followed. The flower, which is normally not possible to dry, was then uncovered and sprayed. Example 3 A small flower with leaves was buried as described above, and the container with the buried plant was placed in an ordinary kitchen oven with a thermostate on 50°C. After 6 hours at this temperature the container was taken out and was allowed to rest for some time to cool off before the mineral composition was carefully removed. The dry plant was then treated with a commercial spraying agent for dry plants, so called "Bladglans" (leaf lustre) , and the plant was allowed to remain uncovered for two hours. The resulting product was a natural, soft plant. Example 4 A flower was buried in the mineral composition described above, and the container with the buried flower was covered and was allowed to remain for one week on a hot bathroom floor. The treated plant was then taken out and submerged for a short period in melted plant wax. After the wax on the plant had become dry, the resulting product was somewhat stiff and shiny, but it was very robust and there¬ fore suited for such uses where it could be subjected to some handling. After each of the above examples the mineral composition was subjected to heating in an open pan in a kitchen oven at about 250°C for about 1 hour. After the subsequent cooling it was again ready for use. Example 5 45 different flowers were buried in the granulate in 7 different boxes made of pasteboard. The boxes were placed in an airing cupboard, and the temperature was set to 70°C. The dryer was left working for 6 hours. The next day the dryer was again started at the same temperature, and left working for 5 hours. Then the flowers were uncovered, and new flowers were laid down in the granulate without re¬ activation.

Claims: P a t e n t c l a i m s 1. Method for preserving an organic material, in parti- cular a plant or a part of a plant, c h a r a c t e r i z e d i n that the organic material under drying conditions such as heating, is kept in contact with a microporous, grainy mineral material having a large internal surface and a high water absorption capacity, and when the orgianic material is dry, the contact is inter¬ rupted, optionally after a certain standing, and the organic material is subjected to a post treatment by protecting its surface against air. 2. Method according to claim 1, c h a r a c t e r i z e d i n that the organic material is covered completely by mineral material in a container and is heated to a temperature not above 100°C, whereafter cooling takes place before the mineral material is removed. 3. Method according to claims 1 - 2, c h a r a c t e r i z e d i n that the organic material is dried in a microwave oven while covered by the mineral material, the drying taking place through three periods: a first period with the oven turned on, a second period with the oven turned off and a third period with the oven turned on. 4. Method according to claim 3, c h a r a c t e r i z e d i n that the first and third period are of approximately equal length. 5. Method according to any of claims 3 and 4, c h a r a c t e r i z e d i n that the second period is from 10 - 30 methods, preferably 15 - 25 minutes, in particular 20 minutes. 6. Method according to any of claims 1 to 5, c h a r a c t e r i z e d i n that the mineral material is a heat treated clay having a grain size of 0.1 - 1.0 mm, particularly 0.4 - 0.8. 7. Method according to claims 1 - 6, c h a r a c t e r i z e d i n that the post treatment takes place by spraying with or submerging in a coating material. 8. The use of a microporous, grainy mineral material having a large internal surface and a high water absorption capacity, in a composition for preserving an organic mate- rial. 9. The use according to claim 8 of a mineral material which is a heat treated clay having grain size of 0.1 - 1.0, in particular 0.4 - 0.8 mm. 10. Kit for preserving organic materials, c h a r a c t e r i z e d i n that it comprises 1) a composition which in its entirety or primarily consists of a microporous mineral material having a large interior surface and a high water absorption capacity, and 2) a coating agent in another package, the coating agent being of such a nature that it may be sprayed on to the organic material, or the organic material may be dipped into the coating agent after the organic material has been dried.

Inventors: OFSTAD KARL-MAGNUS SEIERSTAD, SOEVIK SVEINUNG, OFSTAD, KARL-MAGNUS, SEIERSTAD, SOEVIK, SVEINUNG
Applicants: OFSTAD KARL MAGNUS SEIERSTAD, SOEVIK SVEINUNG, OFSTAD, KARL-MAGNUS, SEIERSTAD, SOEVIK, SVEINUNG
Application year: 1995
Main classification: A01N3
IPC codes: A01G5, A01N3