JPS5839602A - Device for administration of drug to trunk - Google Patents

Abstract

PURPOSE:To obtain the titled device capable of releasing the active component slowly to the tree trunk without loss from the trunk, and preventing and remedying especially the withering of pine effectively for a long period, by mixing an active component, a water-absorbing polymer and a hydrophilic polymer at specific ratios, and forming the mixture in the form of rod or tablet. CONSTITUTION:The objective device for the administration of the active component to the trunk of a tree can be prepared by compounding (A) 10-50wt% active agent (e.g. an antimicrobial agent such as benlate, amicar, etc.), (B) 2- 20wt% water-absorbing polymer capable of absorbing >=100 times volume of water based on its own volume (e.g. startch-acrylamide copolymer, startch- acrylonitrile copolymer, etc.) and (C) 88-30wt% hydrophilic polymer capable of absorbing <=2 times volume of water based on its own volume (e.g. ethylene- vinyl acetate copolymer having vinyl acetate content of >=15wt%), and forming the mixture in the form of rod or tablet. When the device is inserted into the hole bored to the trunk, the water-absorbing polymer absorbs water and swells until the device is brought into close contact with the hole thereby preventing the leak of the active component from the hole.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for administering a drug to a tree trunk, and for example, to a device for gradually administering an antimicrobial agent having preventive and therapeutic effects on tree diseases, especially secretion, into a tree trunk.

Traditionally, liquid or powder insecticides have been sprayed on trees to eliminate or kill pests that neglect trees, and
Insecticides are sprayed into the soil around the base of trees, but with this method, the insecticides are quickly washed away by rain, making it impossible to obtain a sufficient effect. There is a possibility that the water may get mixed into well water or tap water sources, causing environmental pollution. For this reason, a method has been proposed in which an ampoule-shaped bottle made of synthetic resin filled with a liquid containing an insecticide is inserted into a hole drilled in the tree trunk, and the insecticide is directly administered into the tree trunk. (No. 53-115886), since insecticides are administered directly into the tree trunk from the mouth of the bottle, the administration is localized, and on the other hand, the drug lacks sustained release, so there is a risk of concentration disturbance due to the drug. In addition, long-term preventive and therapeutic effects cannot be expected. Furthermore, there is a risk that the drug will leak out through the insertion hole of the bottle into the tree trunk.

The present invention has been made to solve the above-mentioned problems in general, and in particular, certain antimicrobial agents have antibacterial activity against microorganisms that commonly cause tree diseases, particularly secret knots. It is an object of the present invention to provide a device that can effectively prevent and treat secretion, and can gradually administer this antimicrobial agent into a tree trunk without leaking from the tree trunk.

The device for administering a drug to a tree trunk according to the present invention has a drug lO~
50% by weight and a water-absorbing polymer that can absorb more than 100 times its own volume of water.2-20% by weight and about 2 times its own volume.
It is characterized by being made of a hydrophilic polymer that can absorb up to 88 to 30 times the weight of water, and is shaped into a rod or tablet.

In the present invention, the chemicals include insecticides, antimicrobials, fertilizers, nutrients, plant hormones, and other chemicals that are preferably administered directly to the tree trunk.

The device of the present invention is particularly suitable for tree diseases, and among these, it is effective for treating tree diseases, for which no suitable preventive or therapeutic methods have hitherto been available. That is, many tree diseases are caused by filamentous fungi, such as the grape powdery mildew fungus (Uncinula ne-cator).
, Zelkova white astringent fungus (u, aceris D, 0. w
'[Jnc
inela, sooty fungi (Perisporiace
ae), for example, caused by microorganisms such as the genus Qladosporium, and Oeratocystis sp.
Elm Dutch disease (0.51 m1) is a tree disease caused by
), especially the secretion is 0eratocystis.
It has become clear that this is due to infection with sp. According to the present invention, at least one of the following is effective as an antimicrobial agent against these microorganisms: pesticides such as cabtan, gliosin, and benlate, fungicides such as thiopendazole, amical, and biocide, and antibiotics such as kasugamycin, griseofulvin, and polyoxin. In particular, benlate, amical, and polyoxin are effective against tree diseases, especially secret knots.

These antimicrobial agents are powders and are generally difficult to gradually administer and absorb into the tree trunk, but according to the present invention, these antimicrobial agents are combined with water-absorbing polymers and hydrophilic polymers. By molding it and inserting it into a hole pre-drilled in the tree trunk, the water-absorbing polymer absorbs water, swells, and adheres to the hole, preventing the drug from leaking from the hole. The antimicrobial agent is administered to the tree trunk at an appropriate rate to prevent and treat tree diseases.

Here, the water-absorbing polymer refers to a polymer that can absorb 100 times or more of its own volume of water. Preferred specific examples include starch-acryl heptad copolymer, starch-acryloni-Flyl copolymer, and dextran. -Synthetic polymers in the form of acrylonitrile copolymers, gelatin, carrageenan, agar,
It is possible to combine natural electricity such as konnyaku powder.

``Since these water-absorbing aggregates generally have poor affinity with drugs, it is difficult to mold them into a desired shape together with drugs when used alone. Therefore, in the present invention,
A hydrophilic polymer is used to enable molding together with the drug and to suppress the amount of drug released into the tree trunk at an appropriate rate. Here, the hydrophilic polymer only needs to be able to absorb water up to about twice its own volume, and in particular, an ethylene-vinyl acetate copolymer with a vinyl acetate content of 15% or more by weight has a suitable water absorption capacity. It is preferable from the viewpoints of properties such as properties, imparting moldability, and sustained drug release properties. Furthermore, '' is also preferred because the above-mentioned ethylene-vinyl acetate copolymer is gradually dissolved in the terpenoid contained in the resin of the pine tree trunk, and the drug is accordingly gradually released into the tree trunk. In the present invention, the drug, including the antimicrobial agent, preferably accounts for 10 to 50% of the weight of the device.

When the amount of drug is very small, there is sufficient preventive treatment effect, etc.
This is because the desired effect cannot be obtained, and on the other hand, when the amount is too large, it becomes difficult to mold into a molded product, and it also causes chemical damage. The water-absorbing polymer preferably accounts for 2 to 30% by weight of the device. If it is too small, the water absorption and swelling of the device will be insufficient, resulting in poor adhesion when the device is inserted into a hole drilled in a tree trunk, and if it is too large, it will be difficult to mold it into a molded product. . Further, it is desirable that the hydrophilic polymer accounts for 88 to 30% by weight in the device. If the amount is too small, it will be difficult to mold the water-absorbing polymer and the drug, while if it is too large, the amount of drug released will be insufficient.

Devices according to the present invention include, but are not limited to, drugs,
It is obtained by mixing a water-absorbing polymer and a hydrophilic polymer and molding the mixture by extrusion molding or the like.

If necessary, a filler may be used.The filler is used within a range that does not impede the moldability when molding the antimicrobial agent together with the polymer, and is usually 2 parts by weight per 100 parts by weight of the hydrophilic polymer.
A suitable amount is 0 parts by weight or less. As the bulking agent, known ones such as tal powder, tobacco flour, wood flour, clays, talcs, and silicas can be used. In addition, rod-shaped molded products include cylinders and prisms whose cross section is uniform over the entire length, as well as cylinders whose tips are conical, warhead-shaped, and pyramid-shaped.
It includes prismatic cylinders, tapered cylinders whose cross section gradually decreases toward the tip, prismatic cylinders, and combinations thereof, and tablet-shaped molded products include spherical, elliptical, and flat disk shapes. .

The size of the device of the present invention is appropriately selected, but in the case of a rod-shaped molded product, the diameter is usually 5 to 10 cm and the length is 10 to sos.
In the case of a tablet-like molded product, the thickness is, for example, 3 to 1 m.
Appropriately, the diameter is 10 to 20 mm.

When using the device according to the present invention, an appropriate number of holes are usually drilled near the base of the tree trunk depending on the size of the molded product, and the device is inserted into the holes. The water-absorbing polymer absorbs water, swells, and adheres closely to the pores, and at the same time, the drug is dissolved in the water absorbed by the water-absorbing polymer and hydrophilic polymer, and the drug is smoothly and gradually released from the device surface that is in close contact with the pores. Released - absorbed by the stem to achieve its intended purpose. In particular, when the above-mentioned antimicrobial agent is used as a drug, it is suitable for treating secretions for which there has been no fundamental prevention or treatment method.

Examples of the present invention are listed below, but the present invention is not limited thereto.

Example 10 parts by weight of benlate, 50 parts by weight of starch-acrylamide copolymer powder (manufactured by Hoechst, particle size 10-30μ), and 40 parts by weight of ethylene-vinyl acetate copolymer having a vinyl acetate content of 28 parts by weight were uniformly mixed. After mixing and extruding into a rod shape with a diameter of 5 cm using an extruder (die temperature 100°C),
Device B was obtained by cutting into a length of 30 cm.

Similarly, Polyoxin D2011 Kabe, the same Shitenfun-acrylamide copolymer 201H as above [and ethylene-vinyl acetate copolymer 60 with a vinyl acetate content of 40% by weight]
Parts by weight were uniformly mixed and extrusion molded (guinea temperature: 80° C.) to obtain De I (chair P) having the same shape.

Each of the above devices was immersed in 100 d of distilled water and heated to 30°C.
The amount of antimicrobial agent released per device was measured by replacing the distilled water with fresh water every 24 hours. As the results are shown in the drawing, it was confirmed that the antimicrobial agent was slowly released in distilled water over a long period of time.

Next, regarding the 5 pine trees with a height of about 2 m and a diameter of about 201+, Qeratocystis S., the cause of the secret knot, was examined.
P, was injected into a hole drilled in a tree trunk at a height above ground of 10 cIR, and device B (length 10) obtained above was inserted into a hole drilled in a tree trunk at a height above ground of 20 elf. However,
After one row, all of the control group died, but all of the device-inserted groups survived. The same results were obtained for device P.

[Brief explanation of the drawing]

The figure is a graph showing the sustained release of antimicrobial agents when the device of the present invention is immersed in distilled water.

Claims (1)

[Claims] (1) The drug has a weight of 10 to 50 and a self-volume of 10 to 50.
It consists of 2 to 20% by weight of a water-absorbing polymer that can absorb 0 times or more of water and 88 to 30% by weight of a hydrophilic polymer that can absorb about 2 times or less of its own volume of water, and is in the form of a rod or tablet. A device for administering a drug to a tree trunk, characterized in that it is shaped into a shape. 2. The device for administering a drug to a tree trunk according to claim 1, wherein the hydrophilic polymer is an ethylene-vinyl acetate copolymer having a vinyl acetate content of 15 weight or more. (3) The device for administering a drug to a tree trunk according to claim 1, wherein the drug is an antimicrobial agent. (4) A patent claim characterized in that the anti-fouling agent is at least one selected from the group consisting of cabtane, geta-osine, benlate, thiobendazole, amical, biocide, and the group consisting of mycin, griseofulvin, and polyoxin. The device for administering a drug to a tree trunk according to item 3.