Preservation methods for flora and fauna or excavated cultural relics

Abstract

To provide a method for preserving an animal or a plant or an excavated cultural artifact, which can preserve the animal or the plant or the excavated cultural artifact in a state before the excavation for a long time and enables size stability and preservation stability.SOLUTION: A method for preserving an animal or a plant or an excavated cultural artifact comprises: a first step of dipping an object to be preserved such as an excavated cultural artifact in a water-soluble solvent containing low-grade alcohol; a second step of dipping the object passed through the first step in a water-insoluble solvent to replace the object-dipped water-soluble solvent with the water-insoluble solvent; and a third step of solidifying the object passed through the second step to be dipped in the water-insoluble solvent. The water-insoluble solvent is prepared by adding a cationic surfactant to high-grade alcohol mainly containing saturation alcohol of a melting point of 50-70°C. When necessary, a lignophenol or a lignocresol is used as a supplement / complementary color agent for the water-insoluble solvent.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for long-term preservation of plants, animals, and excavated cultural relics in the state they were in before they were excavated, and in particular to an improved method for preserving plants, animals, and excavated cultural relics (hereinafter referred to as "relics, etc.") using higher alcohols. [Background technology]

[0002] Generally, artifacts are the cultural heritage of humanity, and their preservation is extremely important in elucidating the changes in human lifestyles and the environment. Therefore, when preserving artifacts, it is desirable to treat them in such a way that they can be preserved for many years in the condition they were in when they were created.

[0003] Incidentally, artifacts found on land, and especially those excavated from moats surrounding ruins, are usually buried in clay or mud layers, and therefore often contain supersaturated water. For this reason, after excavation, artifacts, especially wooden artifacts, undergo decomposition and leaching of their main component, cellulose, and even if they are initially able to maintain their appearance due to their water content, as they dry out they can shrink dramatically and become deformed to the point where they are no longer recognizable. Plants and animals can also shrink and become deformed to the point where they are no longer recognizable as they dry out.

[0004] For this reason, conventional methods of preserving objects such as relics (hereinafter referred to as "objects") to maintain their original shape include impregnating the object with a water-soluble resin such as heated and melted polyethylene glycol (polyethylene glycol impregnation method), impregnating the object with a mixture of tertiary butyl alcohol and polyethylene glycol in a certain ratio and then vacuum freeze-drying (vacuum freeze-drying method), or impregnating the object with a solution of higher alcohol.

[0005] However, in the polyethylene glycol impregnation method, if polyethylene glycol is used near its dissolution temperature, there is a concern that it will be oxidized by air over a long period of time, causing the polyethylene glycol to change over time to a low molecular weight product. In addition, polyethylene glycol is water-soluble and absorbs moisture from the air, which means that the object after preservation treatment (hereinafter referred to as the "treated object") is prone to deformation and cracking. In order to improve preservation properties, it is necessary to prepare an appropriate installation environment, such as a preservation facility, and the impregnation treatment takes a long time.

[0006] On the other hand, the vacuum freeze-drying method also has the same problems with storage stability as the above method, since the object contains 50-60% polyethylene glycol. In addition, the larger the object to be stored, the greater the rate of change in shape.

[0007] Therefore, a prior art method has been proposed that uses higher alcohols as a preservation method that is less susceptible to temperature effects even at room temperature, can significantly shorten the number of days required for preservation treatment, and can preserve the original form of artifacts for a long period of time (see Patent Document 1). The preservation method for excavated cultural artifacts that uses higher alcohols, as described in Patent Document 1, has already been proposed by the applicant of the present application.

[0008] Patent Document 1 describes two methods for preserving excavated cultural artifacts, each of which comprises the following steps: a first step of immersing an excavated cultural artifact in a water-soluble solvent consisting of a straight-chain or branched alcohol having 1 to 4 carbon atoms to replace the impregnated water in the cultural artifact with the water-soluble solvent; a second step of immersing a cultural artifact impregnated in a water-soluble solvent prepared by adding to a water-insoluble solvent consisting of a higher alcohol composition an amount of a compound consisting solely of a saturated higher alcohol having 16 to 22 carbon atoms and an alkylene oxide in an amount that does not exceed the melting point range of the higher alcohol composition (an amount limited to a range that maintains the melting point range) to replace the impregnated water-soluble solvent in the cultural artifact with the water-insoluble solvent; and a third step of solidifying the cultural artifact impregnated with the water-insoluble solvent.

[0009] In addition, a method for preserving other types of excavated cultural artifacts consists of a first step similar to the first step described above, a second step in which the cultural artifacts impregnated with the water-soluble solvent are immersed in a water-insoluble solvent prepared in the same manner as above, thereby replacing up to 40% of the water-soluble solvent impregnated in the cultural artifacts with the water-insoluble solvent, and a third step in which the cultural artifacts impregnated with the water-soluble and water-insoluble solvents are frozen and dried under vacuum. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Patent No. 4634517 Summary of the Invention [Problem to be solved by the invention]

[0011] When preserving artifacts based on their condition, state of alteration, thickness, material, etc., it is necessary to carefully select various treatment conditions, such as "the antibacterial and bactericidal properties of the preservation treatment solution," and to apply a method appropriate to the object. Even in the method using higher alcohols mentioned above, efforts and improvements are required to ensure that the higher alcohol penetrates into the fine details of the object's structure and to minimize deformation and cracking of the object after treatment due to crystallization during solidification.

[0012] The present invention has been made in response to this current situation, and aims to provide a method for preserving artifacts, etc., which is based on the use of higher alcohols, and which will enable the treated object to retain its intricate structure after the preservation treatment is complete, and which will not be affected by humidity, external temperature, external biological factors, etc., even at room temperature, and which will maintain its condition from before the preservation treatment for a long period of time without changing. [Means for solving the problem]

[0013] The method for preserving plants, animals, or excavated cultural relics according to claim 1 of the present invention comprises the steps of: a first step of immersing an object to be preserved, which is the plant, animal, or excavated cultural relic, in a water-soluble solvent consisting of a straight-chain or branched alcohol having 1 to 4 carbon atoms to replace the impregnated water of the object to be preserved with the water-soluble solvent; and a second step of immersing the object to be preserved, which has been impregnated with the water-soluble solvent through the first step, in a solution of a cationic surfactant in a higher alcohol mainly consisting of a saturated alcohol having a melting point of 50 to 70°C. and lignophenol or lignocresol This method comprises a second step in which the object is immersed in a poorly water-soluble solvent containing the compound (a) and (b) to replace the water-soluble solvent impregnated in the object with the poorly water-soluble solvent, and a third step in which the object, which has been impregnated with the poorly water-soluble solvent through the second step, is solidified. For convenience, this preservation method is referred to as "Preservation Method 1."

[0014] The method for preserving plants, animals, or excavated cultural relics according to claim 2 of the present invention comprises the steps of: a first step of immersing an object to be preserved, which is the plant, animal, or excavated cultural relic, in a water-soluble solvent consisting of a linear or branched alcohol having 1 to 4 carbon atoms to replace the impregnated water of the object with the water-soluble solvent; and a second step of immersing the object to be preserved, which has been impregnated with the water-soluble solvent through the first step, in a solution of a cationic surfactant in a higher alcohol mainly consisting of a saturated alcohol having a melting point of 50 to 70°C. and lignophenol or lignocresol This method comprises a second step in which the object is immersed in a slightly water-soluble solvent containing the above-mentioned compound, thereby replacing at least 40% of the water-soluble solvent impregnated in the object with the slightly water-soluble solvent, and a third step in which the object, now impregnated with the water-soluble or slightly water-soluble solvent after being subjected to the second step, is frozen and dried under vacuum. For convenience, this preservation method is referred to as "Preservation Method 2."

[0015] In the above preservation methods 1 and 2, the reason for performing the first step of immersing the object in a water-soluble solvent before the second step of immersing the object in a poorly water-soluble solvent is that if the object is immediately immersed in a poorly water-soluble solvent, the impregnating water of the object will not be smoothly replaced by the poorly water-soluble solvent, making it difficult for the poorly water-soluble solvent to penetrate into the fine details of the object's structure. Therefore, if the first step of immersing the object in a water-soluble solvent is performed before the second step, as in the above preservation methods 1 and 2, the impregnating water of the object will dissolve into the water-soluble solvent and be smoothly replaced by the water-soluble solvent. Then, by performing the second step of immersing the object in a poorly water-soluble solvent, the water-soluble solvent impregnated in the object will be smoothly replaced by an alcohol-based poorly water-soluble solvent similar to the water-soluble solvent, allowing the poorly water-soluble solvent to penetrate into the fine details of the object's structure in a short period of time, thereby improving the dimensional stability of the object after treatment.

[0016] In the second step of preservation methods 1 and 2, the object impregnated with the water-soluble solvent via the first step is immersed in a water-insoluble solvent. The water-insoluble solvent, consisting of a higher alcohol primarily composed of saturated alcohol with a melting point of 50-70°C and a cationic surfactant (soluble in the higher alcohol), must be selected depending on the condition of the object. For example, it has been shown that treating fragile or embrittled objects at high temperatures can lead to deformation and shrinkage. Conversely, treating objects at low temperatures can lead to a decrease in dimensional stability after treatment due to the external temperature. To further explain this, while relatively good condition objects can be treated at relatively high temperatures, it has been found that, due to the nature of the objects, treatment at temperatures above 70°C can easily cause shrinkage and deformation. In contrast, when a higher alcohol with a melting point of 50°C or lower is used, there is a risk that the higher alcohol will melt when the object is solidified via the third step (Preservation Method 1) or when the object is frozen and dried under vacuum via the third step (Preservation Method 2), and it has been found that the object is susceptible to the effects of external temperature after treatment. For these reasons, it is appropriate to use saturated alcohol with a melting point of 50 to 70°C depending on the treatment temperature.

[0017] In the preservation method 2, the replacement ratio of the water-soluble solvent with the poorly water-soluble solvent obtained by adding a cationic surfactant to a higher alcohol is sufficient if at least about 40% of the water-soluble solvent initially impregnated is replaced with the poorly water-soluble solvent subsequently impregnated, and is preferably about 40 to 60%, and particularly about 50%. If at least about 40% of the water-soluble solvent initially impregnated into the object has been replaced with the poorly water-soluble solvent subsequently impregnated, then by subjecting the object to the third step of freezing and drying under vacuum, only the water-soluble solvent evaporates and disappears from the object, allowing the poorly water-soluble solvent to penetrate into the fine details of the object's structure, improving the dimensional stability of the object after treatment.

[0018] Treated objects that have undergone the second step of preservation methods 1 and 2, specifically immersion in a water-insoluble solvent containing a cationic surfactant in a higher alcohol, may exhibit a white discoloration. This phenomenon hinders the preservation of treated objects while maintaining their original shape. To address this issue, it is desirable to add naturally occurring lignophenols or lignocresols to the water-insoluble solvent and use these lignophenols or lignocresols in combination with cationic surfactants possessing bactericidal or antibacterial properties. Adding cationic surfactants possessing antibacterial or antibacterial properties to higher alcohols, and in some cases using natural lignophenols or lignocresols, which are known to have anti-termite and antiseptic properties, as supplements or color enhancers, results in better penetration into the treated objects than when higher alcohols are used alone, improving the dimensional stability of the treated objects. Furthermore, when the treated objects are plants or animals, preservation stability is also improved.

[0019] The method for preserving plants and animals or excavated cultural relics according to claim 3 of the present invention is characterized in that the content of the cationic surfactant in the poorly water-soluble solvent is an amount that does not exceed the melting point range of the higher alcohol. "The content of the cationic surfactant in the poorly water-soluble solvent is an amount that does not exceed the melting point range of the higher alcohol" means that the amount of cationic surfactant added to the poorly water-soluble solvent is such that the melting point range of the poorly water-soluble solvent does not exceed the melting point range of the higher alcohol, even if the melting point range of the poorly water-soluble solvent changes due to the cationic surfactant added to the poorly water-soluble solvent.

[0020] Claims of the invention 4 In the method for preserving plants and animals or excavated cultural relics, the poorly water-soluble solvent is made by adding 2 to 15 wt% of a cationic surfactant to 85 to 98 wt% of a higher alcohol having 16 to 22 carbon atoms. If the amount of cationic surfactant added is less than 2 wt%, the effect of adding the cationic surfactant is unlikely to be realized, and if the amount of cationic surfactant added is more than 15 wt%, it becomes difficult to secure the necessary amount of poorly water-soluble solvent made by adding the cationic surfactant to the higher alcohol.

[0021] Claims of the invention 5The method for preserving plants, animals, or excavated cultural relics involves replacing a portion of the cationic surfactant contained in the poorly water-soluble solvent with lignophenol or lignocresol at a concentration of up to 3% of the poorly water-soluble solvent. A mixture of a poorly water-soluble solvent, a higher alcohol, and a cationic surfactant may solidify. In this case, using a higher alcohol mixture (poorly water-soluble solvent) with a melting point between 50 and 70°C in which a portion of the cationic surfactant is replaced with naturally occurring lignophenol or lignocresol prevents the formation of large crystals under temperature conditions and also prevents cracks. This allows the poorly water-soluble solvent to more reliably fill the finer parts of the object's structure, resulting in a treated object in which the structure is completely replaced with the poorly water-soluble solvent. This further improves the crystal fineness, dimensional stability, and storage stability of the treated object, making it effective for preserving a wide range of objects. Therefore, in order to maintain the dimensional stability of the treated object, it is optimal to use a mixture consisting of a higher alcohol, mainly a saturated alcohol with a melting point of 50 to 70°C, and a cationic surfactant that is soluble in the higher alcohol and has bactericidal and antibacterial properties, or to use a mixed composition in which part of the cationic surfactant with bactericidal and antibacterial properties is replaced with lignophenol or lignocresol derived from natural products, depending on the condition of the treated object.

[0022] In preservation methods 1 and 2, it is also possible to add soluble fatty acid glycols having 8 to 12 carbon atoms, cellulose alkyl ethers, termite repellents, colorants, etc. to a composition containing a higher alcohol having 16 to 22 carbon atoms, a cationic surfactant, and a surfactant partially substituted with lignophenol or lignocresol.

[0023] In the present invention, the higher alcohol having a melting point of 50 to 70° C. has a carbon number of 16 to 22. Representative examples of such higher alcohols include the following: Cetyl alcohol 70 (melting point 50-54°C, C16 alcohol 70-75%, C18 alcohol 25-30%) Cetyl alcohol 50 (melting point 52-55°C, C16 alcohol 50-55%, C18 alcohol 45-50%) Stearyl alcohol (melting point 57.5-59.5°C, C16 alcohol 20% or less, C18 alcohol 80-90%) Behenyl alcohol 65 (melting point 65-70°C, C22 alcohol 65-70%, C20 alcohol 20% or less, C18 alcohol 20% or less) Cetostearyl alcohol (melting point 54-56°C, C16 alcohol 45-55%, C18 alcohol 45-65%)

[0024] The cationic surfactant to be added to the above-mentioned higher alcohol having a melting point of 50 to 70°C and 16 to 22 carbon atoms is soluble in the higher alcohol and contains a saturated or unsaturated long-chain alkyl group having 8 to 22 carbon atoms in its structure, and examples thereof include the following: Dodecyldimethylbenzylammonium chloride Tetradecyldimethylbenzylammonium chloride Stearyl dimethyl benzyl ammonium chloride Hexadecyldimethylbenzylammonium chloride Octadecyldimethylbenzylammonium chloride Oleyldimethylbenzylammonium chloride Behenyl dimethyl benzyl ammonium chloride Cetylpyridinium chloride

[0025] Lignophenols and lignocresols, which can be used to partially replace cationic surfactants containing saturated or unsaturated long-chain alkyl groups with 8 to 22 carbon atoms, are made by extracting lignin contained in natural wood with phenol or cresol, and have an estimated molecular weight of 1,000 to 5,000 and a thermal flow point of 130 to 170°C. They are manufactured by Fujii Foundation Design Office Co., Ltd. at a manufacturing plant on the island of Okinoshima.

[0026] The plants and animals included in the artifacts, etc., referred to in this invention include all commonly-known plants and animals. Furthermore, excavated cultural artifacts include various artifacts excavated from various ruins and ancient tombs, such as products (pieces of wood, dugout canoes, wooden implements, etc.), metal products (round mirrors, bronze bells, swords, fishhooks, iron implements, etc.), earthenware products (pottery, etc.), animal products (textiles, human bones, animal bones, etc.), and excavated plant and animal products (leaves, textiles, fruits, seeds, hemp, silk, lacquer coatings, etc.). [Effects of the Invention]

[0027] The method for preserving relics and other objects according to the present invention results in a more finely structured solid object after treatment than methods using only higher alcohols as a poorly water-soluble solvent. Furthermore, the method for preserving relics and other objects according to the present invention can be used for a wider range of objects, and the treated object is less susceptible to the effects of humidity, external temperature, and other factors, allowing for long-term preservation in its pre-treatment state. Furthermore, the composition of a poorly water-soluble solvent, a higher alcohol and a cationic surfactant, or a composition containing a higher alcohol and a cationic surfactant partially substituted with lignophenol or lignocresol, forms a finely structured object after treatment, so the treated object does not absorb moisture in the surrounding preservation environment and does not suffer from problems such as aging or cracking. Furthermore, treated objects with such properties, such as treated animals and plants, can be obtained in a shorter processing time. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a process diagram showing a method for preserving relics and the like according to the present invention. [Figure 2] FIG. 10 is a process diagram showing another method for preserving relics, etc. according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0029] The present invention will now be described in further detail.

[0030] 1 showing Preservation Method 1, in the first step, the object is immersed in a water-soluble solvent consisting of a linear (saturated) or branched alcohol having 1 to 4 carbon atoms, and the water impregnated in the object is replaced with the water-soluble solvent. By going through this first step, an object is obtained in which the water contained in the object in a supersaturated state has been replaced with the water-soluble solvent.

[0031] In the next second step, the object impregnated with the water-soluble solvent through the first step is immersed in a poorly water-soluble solvent composed of a higher alcohol, primarily saturated alcohol, with a melting point of 50 to 70°C, to which a cationic surfactant is added, thereby replacing the water-soluble solvent impregnated in the object with the poorly water-soluble solvent. In this second step, lignophenol or lignocresol is added to the poorly water-soluble solvent as needed. Furthermore, lignophenol or lignocresol is added in an amount up to 3% of the poorly water-soluble solvent to replace a portion of the cationic surfactant contained in the poorly water-soluble solvent. Through this second step, an object in which the water-soluble solvent has been completely replaced with the poorly water-soluble solvent is obtained.

[0032] In the third and final step, the object impregnated with the poorly water-soluble solvent is cooled and solidified in air at room temperature and atmospheric pressure, resulting in a treated object that has been preserved using Preservation Method 1.

[0033] 2 showing preservation method 2, in the first step, the object is immersed in a water-soluble solvent consisting of a linear (saturated) or branched alcohol having 1 to 4 carbon atoms, and the water impregnated in the object is replaced with the water-soluble solvent. By going through this first step, an object is obtained in which the water contained in the object in a supersaturated state has been replaced with the water-soluble solvent.

[0034] In the next second step, the object impregnated with the water-soluble solvent through the first step is immersed in a poorly water-soluble solvent composed of a higher alcohol, primarily saturated alcohol, with a melting point of 50 to 70°C, to which a cationic surfactant has been added, thereby replacing at least 40% of the water-soluble solvent impregnated in the object with the poorly water-soluble solvent. In this second step, lignophenol or lignocresol is added to the poorly water-soluble solvent as needed. Furthermore, lignophenol or lignocresol is added to the poorly water-soluble solvent to replace a portion of the cationic surfactant contained in the poorly water-soluble solvent, up to a maximum of 3% of the poorly water-soluble solvent.

[0035] In the final step, the object impregnated with the water-soluble and poorly water-soluble solvents is freeze-dried under vacuum, which evaporates and removes only the water-soluble solvent from the object, yielding a processed object that has been preserved using Preservation Method 2. [Example]

[0036] Next, the embodiment will be described with a specific example.

[0037] [Example 1 ] Example 1 Here, we will explain an example of processing a piece of wood excavated from an archaeological site according to Preservation Method 2.

[0038] Preservation method 2 is almost the same as preservation method 1 up to the intermediate steps. That is, in the first step, wood pieces are placed in tertiary butyl alcohol, a type of lower alcohol that is a water-soluble solvent, and soaked for one to several days. During soaking, all of the moisture in the wood pieces is replaced with tertiary butyl alcohol, resulting in wood pieces in which all of the moisture contained within the wood tissue has been replaced with tertiary butyl alcohol. During soaking in tertiary butyl alcohol, the moisture contained within the wood pieces leaches into the tertiary butyl alcohol, reducing the concentration of the tertiary butyl alcohol, so the specific gravity is measured as appropriate, and the alcohol is replaced with new tertiary butyl alcohol several times along the way.

[0039] As a pretreatment for the next step 2, a mixed composition (melting point 60.19°C) of tertiary butyl alcohol, a type of lower alcohol, the same stearyl alcohol as above, the cationic surfactant cetylpyridinium chloride 4.5%, and lignophenol 0.5% is placed in an incubator and dissolved at 62°C, and the wood pieces are immersed in the mixture maintained at 62°C for several days. This pretreatment is intended to prevent cracking and shrinkage of the wood pieces in the next step 2, which may be caused by differences in concentration and molecular weight between the tertiary butyl alcohol and the higher alcohol, which is a poorly water-soluble solvent.

[0040] In the second step, a mixed composition (melting point 60.91°C) of the same higher alcohol stearyl alcohol as above, the cationic surfactant cetylpyridinium chloride 4.5%, and lignophenol 0.5% is placed in an incubator and melted at 62°C, and the wood pieces are immersed in the mixture maintained at 62°C for several days. When about 50% of the tertiary butyl alcohol in the wood pieces has been replaced with the mixed composition consisting of stearyl alcohol, cetylpyridinium chloride, and lignophenol, the immersion is terminated and the wood pieces are removed from the incubator.

[0041] In the third step, the wood pieces are flash-frozen in a freezer and then dried using a vacuum freeze-drying device. This causes all of the tertiary butyl alcohol remaining in the wood pieces to sublimate and disappear, but the mixed composition consisting of stearyl alcohol, cetylpyridinium chloride, and lignophenol is a resistant solid and remains within the wood piece's tissue. As the drying process progresses, the wood pieces solidify, and finally, a solid post-treatment object that has been preserved using Preservation Method 2 is obtained. This post-treatment object (wood piece), a cultural artifact treated using Preservation Method 2, retains its original shape before excavation and can be preserved semi-permanently without deformation. Furthermore, the post-treatment object possesses the reversibility required for the conservation treatment of this type of cultural artifact.

[0042] [Example 2 ] This example 2Here, we will explain an example of processing rice varieties (Kame no O) seven days after harvesting according to preservation method 1.

[0043] In the first step, one rice stalk (Kame no O) is placed in methyl alcohol, a water-soluble solvent, and soaked for several days. During soaking, all of the water in the rice is replaced with methyl alcohol, resulting in rice in which all of the water contained in the rice tissue has been replaced with methyl alcohol. During soaking, the water contained in the rice leaches into the methyl alcohol, reducing the concentration of the methyl alcohol, so the specific gravity is measured as appropriate and the methyl alcohol is replaced with new methyl alcohol several times during the soaking process.

[0044] As a pretreatment for the next second step, a mixture of methyl alcohol, a lower alcohol, stearyl alcohol, a higher alcohol, as described above, and 4.5% stearyldimethylbenzylammonium chloride, a benzalkonium-type cationic surfactant (melting point 60.19°C) was placed in an incubator and dissolved at 62°C. The pretreated rice was then placed in the mixture, maintained at 62°C, and soaked for several days. The reason for this pretreatment is as described above.

[0045] In the second step, a mixture of the same higher alcohol stearyl alcohol as above, 4.5% stearyldimethylbenzylammonium chloride, a benzalkonium-type cationic surfactant, and 0.5% lignocresol as an adjuvant (melting point 60.20°C) is placed in an incubator and melted at 62°C. The pretreated rice plants are immersed in the mixture, maintained at 62°C, for several days. This completely replaces the methyl alcohol in the rice with a mixture of stearyl alcohol, stearyldimethylbenzylammonium chloride, and lignocresol. After the replacement is complete, the rice plants are removed from the incubator. In the third step, the rice is cooled and solidified at room temperature to obtain a treated object (rice) that has been preserved using Preservation Method 1. The treated object, a cultural relic treated in this way, retains its original shape from before it was excavated and can be preserved semi-permanently without deformation. The treated object also possesses the reversibility required for the preservation of this type of cultural relic.

[0046] Dimensional stability was evaluated by measuring the length of the portion of the leaf 10 cm from the tip along the vein (vein direction) and the portion perpendicular to the vein (horizontal direction) of 10 leaves of rice plants before treatment and comparing the measurements of the same positions on the treated rice plants. Treated specimen (1) was preserved using a mixture of stearyl alcohol, a higher alcohol, and the benzalkonium-type cationic surfactant stearyl dimethyl benzyl ammonium chloride and lignocresol. Treated specimen (2) was preserved using only stearyl alcohol as the water-insoluble solvent. Dimensional changes before and after treatment were also compared for treated specimens (1) and (2).

[0047] [Dimensional change] Post-processing target Leaf vein direction Horizontal direction (1) 0.01% 0.1% (2) 0.015% 0.2%

[0048] This shows that the treated object (1) preserved by preservation method 1 has smaller dimensional changes in the vein and lateral directions than the treated object (2).

Claims

1. a first step in which the object to be preserved, which is an animal, plant, or excavated cultural relic, is immersed in a water-soluble solvent consisting of a linear or branched alcohol having 1 to 4 carbon atoms to replace the water impregnated in the object to be preserved with the water-soluble solvent; a second step in which the object to be preserved, which has been impregnated with the water-soluble solvent through the first step, is immersed in a water-insoluble solvent consisting of a higher alcohol, mainly saturated alcohol with a melting point of 50-70°C, to which a cationic surfactant and lignophenol or lignocresol have been added, thereby replacing the water-soluble solvent impregnated in the object to the water-insoluble solvent; a third step of solidifying the object to be preserved that has been impregnated with the poorly water-soluble solvent through the second step; A method for preserving plants and animals or excavated cultural relics, comprising:

2. a first step in which the object to be preserved, which is an animal, plant, or excavated cultural relic, is immersed in a water-soluble solvent consisting of a linear or branched alcohol having 1 to 4 carbon atoms to replace the water impregnated in the object to be preserved with the water-soluble solvent; a second step in which the object to be preserved, which has been impregnated with the water-soluble solvent through the first step, is immersed in a water-insoluble solvent consisting of a higher alcohol, mainly saturated alcohol with a melting point of 50-70°C, to which a cationic surfactant and lignophenol or lignocresol have been added, thereby replacing at least 40% of the water-soluble solvent impregnated in the object to the water-insoluble solvent; a third step of freezing and drying under vacuum the object to be preserved that has been impregnated with the water-soluble or poorly water-soluble solvent through the second step; A method for preserving plants and animals or excavated cultural relics, comprising:

3. 3. A method for preserving plants and animals or excavated cultural relics according to claim 1 or 2, wherein the content of the cationic surfactant in the poorly water-soluble solvent is an amount that does not exceed the melting point range of the higher alcohol.

4. 4. A method for preserving plants and animals or excavated cultural relics according to any one of claims 1 to 3, wherein the poorly water-soluble solvent is a mixture of 85 to 98% of a higher alcohol having 16 to 22 carbon atoms and 2 to 15% of a cationic surfactant.

5. A method for preserving plants, animals, or excavated cultural relics as described in claim 4, in which lignophenol or lignocresol is added to the poorly water-soluble solvent in an amount up to 3% of the poorly water-soluble solvent in place of a portion of the cationic surfactant contained in the poorly water-soluble solvent.

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