Housing for livestock sensors and livestock sensors

Abstract

To provide a housing for a stock-raising sensor capable of constituting a stock-raising sensor easy to administer orally to livestock.SOLUTION: A housing for a stock-raising sensor contains a resin in which a coefficient of dynamic friction is 0.40 or less and a coefficient of static friction is 0.10 or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a housing for a livestock sensor and a livestock sensor.

Background Art

[0002] In recent years, in the livestock field, it has been considered to implant a sensor in a cow's body to manage the health and reproduction of cows.

[0003] Patent Document 1 describes a detection device for detecting the internal state of a cow's rumen, which includes a stainless-steel container body and a tapered resin (e.g., polypropylene) cap.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of the present disclosure is to provide a housing for a livestock sensor that can constitute a livestock sensor that is easy to orally administer to livestock, and a livestock sensor using the same.

Means for Solving the Problems

[0006] The present disclosure relates to a housing for a livestock sensor containing a resin having a dynamic friction coefficient of 0.40 or less and a static friction coefficient of 0.10 or less.

[0007] Preferably, the resin has an elastic modulus of 1.5 GPa or less at 25°C.

[0008] Preferably, the resin is a fluororesin.

[0009] The resin is preferably at least one selected from the group consisting of polytetrafluoroethylene, tetrafluoroethylene / perfluoro(alkyl vinyl ether) copolymer, tetrafluoroethylene / hexafluoropropylene copolymer, ethylene / tetrafluoroethylene copolymer, tetrafluoroethylene / perfluoroalkyl allyl ether copolymer, and polychlorotrifluoroethylene.

[0010] The resin is preferably a fluororesin that can be melt-processed.

[0011] The resin preferably has a mass change rate of less than 0.5% after being immersed in a 50% by mass formic acid aqueous solution at 50 °C for one week.

[0012] The present disclosure also relates to an animal husbandry sensor including the housing for the animal husbandry sensor and a detection unit housed inside the housing.

Effects of the Invention

[0013] According to the present disclosure, it is possible to provide a housing for an animal husbandry sensor that can constitute an animal husbandry sensor that is easy to orally administer to livestock, and an animal husbandry sensor using the same.

Brief Description of the Drawings

[0014]

Figure 1

Modes for Carrying Out the Invention

[0015] Conventionally, the housing used for an animal husbandry sensor has been formed by devising its shape and size so as to be easy to orally administer. As a result of intensive studies from a perspective different from the conventional ones, the present inventors have found that by forming the housing with a resin having specific dynamic and static friction coefficients, it is possible to constitute an animal husbandry sensor that is easy to orally administer to livestock, and have thus completed the housing for an animal husbandry sensor of the present disclosure.

[0016] The following specifically describes the present disclosure.

[0017] The housing for the livestock sensor of the present disclosure contains a resin with a kinetic friction coefficient of 0.40 or less and a static friction coefficient of 0.10 or less. By using a resin with a kinetic friction coefficient of 0.40 or less and a static friction coefficient of 0.10 or less, a livestock sensor that is slippery, easy for livestock to swallow, and easy to administer orally can be configured. Therefore, it is possible to obtain highly reliable data without stressing the livestock. In addition, since there are fewer restrictions on the shape and size of the housing, the degree of freedom in design is improved.

[0018] The above kinetic friction coefficient is preferably 0.10 or less, more preferably 0.08 or less, and even more preferably 0.04 or less. The above kinetic friction coefficient may also be 0.01 or more. The above static friction coefficient is preferably 0.07 or less, more preferably 0.05 or less, and even more preferably 0.03 or less. The above static friction coefficient may also be 0.01 or more. The above kinetic friction coefficient and static friction coefficient are measured in contact with a chromium-plated steel plate at room temperature in accordance with JIS K 7125.

[0019] The above resin preferably has an elastic modulus at 25°C of 1.5 GPa or less. By having the elastic modulus within the above range, a soft housing that is less likely to damage the inside of the livestock's body (such as the inner wall of the stomach) can be obtained. Therefore, it is possible to obtain highly reliable data without stressing the livestock. The above elastic modulus is more preferably 0.7 GPa or less, and even more preferably 0.5 GPa or less. The above elastic modulus may also be 0.1 GPa or more. The above elastic modulus is measured at 25°C in accordance with ASTM D638.

[0020] The resin preferably has a mass change rate of less than 0.5% after being immersed in a 50% by mass formic acid aqueous solution at 50°C for one week. When the mass change rate is within the above range, the housing is less likely to corrode even when in long-term contact with acidic body fluids such as gastric juice. More preferably, the mass change rate is 0.4% or less, and even more preferably 0.3% or less. The mass change rate may also be 0.1% or more.

[0021] Examples of the resin include fluororesins, non-fluororesins blended with fluorine-containing repellents, non-fluororesins blended with fluororesins, fluoropolyether group-containing silyl compounds, silicone resins, and the like. Among them, fluororesins are preferred in that it is easy to keep the coefficient of kinetic friction, the coefficient of static friction, and the elastic modulus within the above ranges, and they also have excellent corrosion resistance to acids such as gastric juice.

[0022] The fluororesin preferably has a melting point of 100 to 360°C, more preferably 140 to 350°C, and even more preferably 160 to 320°C. The melting point is the temperature corresponding to the maximum value in the melting heat curve when the temperature is raised at a rate of 10°C / min using a differential scanning calorimeter [DSC].

[0023] Examples of the fluororesin include polytetrafluoroethylene [PTFE], tetrafluoroethylene [TFE] / perfluoro(alkyl vinyl ether) [PAVE] copolymer [PFA], TFE / hexafluoropropylene [HFP] copolymer [FEP], ethylene [Et] / TFE copolymer [ETFE], Et / TFE / HFP copolymer [EFEP], polychlorotrifluoroethylene [PCTFE], chlorotrifluoroethylene [CTFE] / TFE copolymer, CTFE / TFE / PAVE copolymer, Et / CTFE copolymer, polyvinyl fluoride [PVF], polyvinylidene fluoride [PVdF], vinylidene fluoride [VdF] / TFE copolymer, VdF / HFP copolymer, VdF / TFE / HFP copolymer, VdF / HFP / (meth)acrylic acid copolymer, VdF / CTFE copolymer, VdF / pentafluoropropylene copolymer, VdF / PAVE / TFE copolymer, TFE / perfluoroalkyl allyl ether copolymer, etc. The perfluoroalkyl allyl ether is a monomer represented by CF2=CFCF2-O-Rf 4 (Rf 4 is a perfluoroalkyl group having 1 to 5 carbon atoms).

[0024] Among them, at least one selected from the group consisting of PTFE, PFA, FEP, ETFE, TFE / perfluoroalkyl allyl ether copolymer and PCTFE is preferable as the fluororesin, at least one selected from the group consisting of PTFE, PFA, FEP and ETFE is more preferable, at least one selected from the group consisting of PTFE, PFA and FEP is still more preferable, and at least one selected from the group consisting of PFA and FEP is particularly preferable.

[0025] The above PTFE may be a TFE homopolymer consisting only of tetrafluoroethylene (TFE) units, or a modified PTFE containing TFE units and modified monomer units based on modified monomers copolymerizable with TFE.

[0026] The above-mentioned modified monomer is not particularly limited as long as it can copolymerize with TFE. Examples thereof include perfluoroolefins such as hexafluoropropylene [HFP]; chlorofluoroolefins such as chlorotrifluoroethylene [CTFE]; hydrogen-containing fluoroolefins such as trifluoroethylene and vinylidene fluoride [VdF]; perfluorovinyl ether; perfluoroalkyl allyl ether; (perfluoroalkyl)ethylene; ethylene and the like. Further, the modified monomer used may be one kind or a plurality of kinds.

[0027] The above-mentioned perfluorovinyl ether is not particularly limited. For example, the following general formula (1) CF2=CF-ORf (1) (In the formula, Rf represents a perfluoro organic group.) Perfluoro unsaturated compounds represented by the like can be mentioned. In this specification, the above-mentioned "perfluoro organic group" means an organic group in which all hydrogen atoms bonded to carbon atoms are substituted by fluorine atoms. The above-mentioned perfluoro organic group may have an ether oxygen.

[0028] As the above-mentioned perfluorovinyl ether, for example, in the above general formula (1), perfluoro(alkyl vinyl ether) [PAVE] in which Rf represents a perfluoroalkyl group having 1 to 10 carbon atoms can be mentioned. The number of carbon atoms of the above-mentioned perfluoroalkyl group is preferably 1 to 5.

[0029] Examples of the perfluoroalkyl group in the above PAVE include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, a perfluorohexyl group and the like. Perfluoro(propyl vinyl ether) [PPVE] in which the perfluoroalkyl group is a perfluoropropyl group is preferable.

[0030] As the above-mentioned perfluorovinyl ether, further, in the above general formula (1), those in which Rf is a perfluoro(alkoxyalkyl) group having 4 to 9 carbon atoms, Rf is the following formula:

[0031]

Chem.

[0032] (wherein m represents an integer of 0 or 1 to 4). A group represented by Rf is the following formula:

[0033]

Chem.

[0034] (wherein n represents an integer of 1 to 4). Examples thereof include those which are groups represented by the formula.

[0035] The (perfluoroalkyl)ethylene is not particularly limited. For example, (perfluorobutyl)ethylene [PFBE], (perfluorohexyl)ethylene [PFHE], (perfluorooctyl)ethylene and the like can be mentioned.

[0036] The modifying monomer in the above modified PTFE is preferably at least one selected from the group consisting of HFP, CTFE, VdF, PPVE, PFBE and ethylene. More preferably, it is at least one selected from the group consisting of HFP and CTFE.

[0037] In the above modified PTFE, the content of the above modifying monomer unit is preferably in the range of 0.00001 to 1.0% by mass. As the lower limit of the content of the modifying monomer unit, 0.0001% by mass is more preferable, 0.001% by mass is still more preferable, 0.005% by mass is still more preferably, 0.010% by mass is particularly more preferable, and 0.030% by mass is particularly preferable. As the upper limit of the content of the modifying monomer unit, 0.90% by mass is preferable, 0.50% by mass is more preferable, 0.40% by mass is still more preferable, and 0.30% by mass is still more preferable. As used herein, the above-mentioned modified monomer unit means a part of the molecular structure of modified PTFE that is derived from the modified monomer, and the total monomer unit means a part of the molecular structure of modified PTFE that is derived from all monomers.

[0038] The above-mentioned PTFE preferably has a melting point of 324 to 360 °C. The melting point of the above-mentioned PTFE means the first melting point. The above-mentioned first melting point is the temperature corresponding to the maximum value in the melting heat curve when the temperature is raised at a rate of 10 °C / min using a differential scanning calorimeter [DSC] for PTFE that has no heating history at a temperature of 300 °C or higher.

[0039] The above-mentioned PTFE preferably has a standard specific gravity (SSG) of 2.130 to 2.280. The above-mentioned standard specific gravity is more preferably 2.220 or less, and even more preferably 2.200 or less. Also, it is preferably 2.140 or more, and even more preferably 2.150 or more. The above-mentioned SSG is measured by the water displacement method in accordance with ASTM D-792 using a sample molded in accordance with ASTM D 4895-89.

[0040] The above-mentioned PTFE preferably has non-melting secondary processability. The above-mentioned non-melting secondary processability means the property that the melt flow rate cannot be measured at a temperature higher than the crystallization melting point in accordance with ASTM D-1238 and D-2116.

[0041] The above-mentioned PFA is not particularly limited, but a copolymer in which the molar ratio of the TFE unit to the PAVE unit (TFE unit / PAVE unit) is 70 / 30 or more and less than 99 / 1 is preferred. A more preferred molar ratio is 70 / 30 or more and 98.9 / 1.1 or less, and an even more preferred molar ratio is 80 / 20 or more and 98.9 / 1.1 or less. It is also preferred that the above-mentioned PFA is a copolymer in which the monomer units derived from monomers copolymerizable with TFE and PAVE are 0.1 to 10 mol% (the total of the TFE unit and the PAVE unit is 90 to 99.9 mol%), more preferably 0.1 to 5 mol%, and particularly preferably 0.2 to 4 mol%.

[0042] Monomers copolymerizable with TFE and PAVE include HFP, formula (I): CZ 1 Z 2 =CZ 3 (CF2) n Z 4 (wherein Z 1 、Z 2 and Z 3 are the same or different and represent a hydrogen atom or a fluorine atom, and Z 4 represents a hydrogen atom, a fluorine atom or a chlorine atom, and n represents an integer from 2 to 10.) Vinyl monomers represented by, and formula (II): CF2=CF-OCH2-Rf 1 (wherein Rf 1 represents a perfluoroalkyl group having 1 to 5 carbon atoms.) Alkyl perfluorovinyl ether derivatives represented by, formula (X): CZ 5 Z 6 =CZ 7 -CZ 8 Z 9 -O-Rf 4 (wherein, in the formula, Z 5 、Z 6 and Z 7 are the same or different and represent a hydrogen atom, a chlorine atom or a fluorine atom, Z 8 and Z 9 represent a hydrogen atom or a fluorine atom, and Rf 4 represents a perfluoroalkyl group having 1 to 5 carbon atoms.) Allyl ether monomers represented by, etc. are exemplified. As the above allyl ether monomers, CH2=CFCF2-O-Rf 4 、CF2=CFCF2-O-Rf 4 (perfluoroalkyl allyl ether), CF2=CFCH2-O-Rf 4 、CH2=CHCF2-O-Rf 4 (wherein Rf 4 is the same as the above formula (X)) etc. are preferably exemplified. In addition, monomers copolymerizable with TFE and PAVE further include unsaturated monocarboxylic acids, unsaturated dicarboxylic acids, acid anhydrides of unsaturated dicarboxylic acids, such as itaconic acid, itaconic anhydride, citraconic anhydride, and 5-norbornene-2,3-dicarboxylic anhydride.

[0043] The above-mentioned PFA preferably has a melting point of 180 to less than 324 °C, more preferably 230 to 320 °C, and even more preferably 280 to 320 °C.

[0044] The above-mentioned FEP is not particularly limited, but a copolymer having a molar ratio of TFE unit to HFP unit (TFE unit / HFP unit) of 70 / 30 or more and less than 99 / 1 is preferable. A more preferable molar ratio is 70 / 30 or more and 98.9 / 1.1 or less, and an even more preferable molar ratio is 80 / 20 or more and 98.9 / 1.1 or less. The above-mentioned FEP is also preferably a copolymer in which monomer units derived from monomers copolymerizable with TFE and HFP are 0.1 to 10 mol% (the total of TFE units and HFP units is 90 to 99.9 mol%), more preferably 0.1 to 5 mol%, and particularly preferably 0.2 to 4 mol%.

[0045] Examples of monomers copolymerizable with TFE and HFP include PAVE, monomers represented by formula (X), alkyl perfluorovinyl ether derivatives represented by formula (II), and the like. In addition, examples of monomers copolymerizable with TFE and HFP further include unsaturated monocarboxylic acids, unsaturated dicarboxylic acids, acid anhydrides of unsaturated dicarboxylic acids, such as itaconic acid, itaconic anhydride, citraconic anhydride, and 5-norbornene-2,3-dicarboxylic anhydride.

[0046] The above-mentioned FEP preferably has a melting point of 150 to less than 324 °C, more preferably 200 to 320 °C, and even more preferably 240 to 320 °C.

[0047] The above-mentioned ETFE is preferably a copolymer having a molar ratio of TFE unit to ethylene unit (TFE unit / ethylene unit) of 20 / 80 or more and 90 / 10 or less. A more preferable molar ratio is 37 / 63 or more and 85 / 15 or less, and an even more preferable molar ratio is 38 / 62 or more and 80 / 20 or less. ETFE may also be a copolymer composed of TFE, ethylene, and monomers copolymerizable with TFE and ethylene. Examples of copolymerizable monomers include the following formula CH2=CX 1 Rf 2 、 CF2=CFRf 2 、 CF2=CFORf 2 、 CH2=C(Rf 2 )2 (wherein, X 1 is a hydrogen atom or a fluorine atom, and Rf 2 represents a fluoroalkyl group which may contain an ether bond.) Monomers represented by the formula (X) and monomers represented by the formula (X) are exemplified. Among them, CF2=CFRf 2 、 CF2=CFORf 2 and CH2=CX 1 Rf 2 -containing fluorine vinyl monomers represented by the formula (X) and monomers represented by the formula (X) are preferred. HFP, CF2=CF-ORf 3 (wherein, Rf 3 represents a perfluoroalkyl group having 1 to 5 carbon atoms.) Perfluoro(alkyl vinyl ether) represented by the formula (X), CF2=CF-CF2-O-Rf 4 (wherein, Rf 4 represents a perfluoroalkyl group having 1 to 5 carbon atoms.) Perfluoroalkyl allyl ether represented by the formula (X) and Rf 2 is a fluorine-containing vinyl monomer represented by CH2=CX 1 Rf 2 wherein Rf is a fluoroalkyl group having 1 to 8 carbon atoms is more preferred. Further, as the monomer copolymerizable with TFE and ethylene, an aliphatic unsaturated carboxylic acid such as itaconic acid and itaconic anhydride may be used. The monomer copolymerizable with TFE and ethylene is preferably 0.1 to 10 mol%, more preferably 0.1 to 5 mol%, and particularly preferably 0.2 to 4 mol% based on the fluorine-containing polymer.

[0048] The above ETFE preferably has a melting point of 140 to less than 324 °C, more preferably 160 to 320 °C, and still more preferably 195 to 320 °C.

[0049] The content of each monomer unit of the above-mentioned polymer can be calculated by appropriately combining NMR, FT-IR, elemental analysis, and X-ray fluorescence analysis according to the type of monomer.

[0050] It is also preferable that the fluororesin is a melt-processable fluororesin. When the fluororesin is melt-processable, the processability is improved. In this specification, being melt-processable means that it is possible to melt and process a polymer using conventional processing equipment such as an extruder and an injection molding machine. The melt-processable fluororesin preferably has a melt flow rate (MFR) of 0.1 to 100 g / 10 min, more preferably 0.5 to 50 g / 10 min. In this specification, MFR is determined according to ASTM D1238 using a melt indexer at a measurement temperature (for example, 372 °C for PFA and FEP, 297 °C for ETFE), a load (for example, 5 kg for PFA, FEP, and ETFE) determined according to the type of fluoropolymer, and is the mass (g / 10 min) of the polymer flowing out per 10 minutes from a nozzle with an inner diameter of 2 mm and a length of 8 mm.

[0051] Examples of the melt-processable fluororesin include PFA, FEP, ETFE, EFEP, PCTFE, PVdF, etc. described above. At least one selected from the group consisting of PFA, FEP, and ETFE is preferable, and at least one selected from the group consisting of PFA and FEP is more preferable.

[0052] The housing of the present disclosure preferably has a resin layer containing the above resin. The content of the above resin is preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, and may be 100% by mass or less with respect to the above resin layer.

[0053] The housing of the present disclosure may have only the above resin layer, or may be a laminate of the above resin layer and another layer. As the other layer, a metal layer is preferable in terms of having a large specific gravity. As the metal constituting the metal layer, stainless steel, steel, brass, copper, etc. are preferable, and stainless steel is more preferable. When providing the above metal layer, it is preferable to provide a portion without the metal layer on a part of the housing so as not to completely shield radio waves.

[0054] When providing the above other layer, it is preferable to laminate it so that the resin layer is on the outer layer side, and it is more preferable to laminate it so that the resin layer is the outermost layer.

[0055] The housing of the present disclosure is preferably a member capable of accommodating a detection unit and other necessary components inside. Further, the housing of the present disclosure may be configured so that a part of it can be separated (for example, like a main body and a cap).

[0056] The shape of the housing of the present disclosure may be any shape capable of accommodating a detection unit and other necessary components inside. For example, a cylindrical shape (circular cylindrical shape, rectangular cylindrical shape, etc.), a bottle shape, a bottomed cylindrical shape, a bottomed rectangular cylindrical shape, etc. can be adopted. Among them, a cylindrical shape, a bottle shape, a bottomed cylindrical shape, or a bottomed rectangular cylindrical shape is preferable, and a circular cylindrical shape or a bottomed cylindrical shape is more preferable.

[0057] The housing of the present disclosure can be manufactured by molding the above resin by a known molding method such as cutting, injection molding, extrusion molding, compression molding, etc. When providing the above-mentioned other layer, a known lamination method can also be adopted. One of the preferable methods is a method of covering the outer periphery of a cylindrical base material (other layer) with a tube made of the above resin and heat-shrinking the tube. Also, a method of applying a paint containing the above resin on the other layer may be used.

[0058] The housing of the present disclosure is for an animal husbandry sensor and is used to constitute an animal husbandry sensor.

[0059] The present disclosure also relates to an animal husbandry sensor including the above-mentioned housing for an animal husbandry sensor of the present disclosure and a detection unit housed inside the housing. Since the livestock sensor of the present disclosure includes the housing of the present disclosure, it is slippery, easy for livestock to swallow, and easy to administer orally. Therefore, it is possible to obtain highly reliable data without stressing the livestock. In addition, since there are fewer restrictions on the shape and size of the housing, the degree of freedom in design is improved.

[0060] The above livestock sensor is a sensor that is indwelled in the body of livestock and detects the state of livestock (pH, temperature, amount of movement (acceleration), etc.). It is preferable that the above livestock sensor is configured to be orally administrable to livestock. Further, it is preferable that the above livestock sensor is a wireless transmission type sensor capable of wirelessly transmitting the acquired data.

[0061] Examples of the above detection unit include a pH sensor, a temperature sensor, a piezoelectric sensor, an acceleration sensor, a position sensor, and the like.

[0062] As the above livestock, ruminants are preferable, and examples include cows (dairy cows, beef cattle), sheep, goats, etc. Among them, cows are preferable.

[0063] The above livestock sensor is preferably indwelled in the internal organs of livestock, more preferably indwelled in the stomach, still more preferably indwelled in the rumen (first stomach), and particularly preferably indwelled in the rumen fluid.

[0064] The above livestock sensor is preferably indwelled in the body of livestock for 1 month or more, more preferably 6 months or more, still more preferably 1 year or more, and particularly preferably 3 years or more.

[0065] The above livestock sensor preferably has a specific gravity of 1.8 or more, more preferably 2.0 or more. By having the specific gravity within the above range, it becomes easy to indwell (sink) in body fluids such as gastric juice.

[0066] The size of the above-mentioned livestock sensor is not particularly limited as long as it can be orally administered to livestock. However, in the case of a cylindrical shape, for example, the diameter may be 10 to 35 mm and the length may be 40 to 150 mm.

[0067] An example of the structure of the livestock sensor of the present disclosure is shown in FIG. 1, but the livestock sensor of the present disclosure is not limited thereto. In FIG. 1, the livestock sensor 10 includes a housing 11, and the housing 11 corresponds to the housing of the present disclosure. Inside the housing 11, a signal processing circuit 13 connected to a battery 12 is accommodated. The signal processing circuit 13 is provided with an acceleration sensor 14 and a wireless transmitter 17. Further, a temperature sensor 15 and a fixed pH sensor 16 are electrically connected to the signal processing circuit 13. Parts of the temperature sensor 15 and the fixed pH sensor 16 are exposed outside the housing 11 so as to be in contact with the rumen fluid.

Examples

[0068] Next, the present disclosure will be described in more detail with reference to examples, but the present disclosure is not limited to these examples only.

[0069] The resins used in each test example, example and comparative example are shown below. PTFE: TFE homopolymer (melting point: 327 ° C, SSG: 2.2) PFA: TFE / PPVE copolymer (melting point: 306 ° C, MFR: 1 g / 10 min) FEP: TFE / HFP copolymer (melting point: 265 ° C, MFR: 2 g / 10 min) ETFE: Et / TFE copolymer (melting point: 265 ° C, MFR: 5 g / 10 min) PCTFE: CTFE homopolymer (melting point: 210 ° C, flow value: 1.5×10 -3 cc / s (230 ° C, 980 N, nozzle diameter 1 mmφ)) High-density polyethylene (HDPE): Novatec HD HJ490 manufactured by Japan Polyethylene Corporation Low-density polyethylene (LDPE): J2522 manufactured by Ube Maruzen Polyethylene Co., Ltd. Polypropylene (PP): Novatec PP BC2E manufactured by Japan Polyethylene Corporation Polystyrene (PS): GPPS 679 manufactured by PS Japan Corporation Polyvinyl chloride (PVC): Kanebinyl S-400 manufactured by Kaneka Corporation Nylon: UBE NYLON 1024JI manufactured by Ube Industries, Ltd. Polycarbonate (PC): Lupilon H-3000 manufactured by Mitsubishi Engineering-Plastics Corporation The above MFR is the value measured according to ASTM D1238. The flow value of PCTFE is the value measured by an elevated-type flow tester.

[0070] Test Example 1 Using each resin, a sheet with a thickness of 0.2 mm and a diameter of 120 mm was produced by compression molding using a heat press. For PTFE, it was molded at a temperature 50 - 70 °C higher than the melting point and a pressure of 5 MPa. For the other resins, it was molded at a temperature 40 °C higher than the melting point and a pressure of 3 MPa. The coefficient of kinetic friction, coefficient of static friction, and elastic modulus of the obtained sheet were measured by the following methods. The results are shown in Table 1.

[0071] <Coefficient of kinetic friction, coefficient of static friction> Measured in contact with a chromium-plated steel sheet at room temperature in accordance with JIS K 7125. <Elastic modulus> Measured at 25 °C in accordance with ASTM D638.

[0072]

Table 1

[0073] Examples 1 - 5 and Comparative Examples 1 - 2 A SUS304 housing with a diameter of φ30mm and a length of 150mm was covered with a resin heat shrinkable tube shown in Table 2 with a diameter of φ36mm, a wall thickness of 0.5mm, and a length of 170mm. Then, the tube was shrunk by heating it at the melting point of the heat shrinkable tube +20°C for 10 minutes to cover the SUS housing with resin. A sensor was assembled to the housing covered with resin, and the following simulated ingestion test was conducted. The results are shown in Table 2.

[0074] <Simulated ingestion test> The time for the sample to pass through a neoprene rubber tube with a diameter of φ40mm and a length of 1000mm installed at an inclination of 45 degrees was measured and evaluated according to the following criteria. ○: Less than 10 seconds △: Less than 20 seconds ×: 20 seconds or more or the sample does not come out

[0075] <Chemical resistance> The test pieces (the above sheet, stainless steel) were immersed in a 50% by mass formic acid aqueous solution at 50°C for one week, and the mass change before and after immersion was measured and evaluated according to the following criteria. In the case of cracks, rust, etc., it was rated as × regardless of the weight change. ○: Weight change rate less than 0.5% △: Weight change rate of 0.5% or more and less than 10% ×: Weight change rate of 10% or more

[0076]

Table 2

Explanation of symbols

[0077] 10: Sensor for livestock 11: Housing 12: Battery 13: Signal processing circuit 14: Acceleration sensor 15: Temperature sensor 16: Fixed pH sensor 17: Wireless transmitter

Claims

1. A housing for a livestock sensor containing a resin with a dynamic friction coefficient of 0.40 or less and a static friction coefficient of 0.10 or less (excluding polytetrafluoroethylene and tetrafluoroethylene / hexafluoropropylene copolymer).

2. The housing for a livestock sensor according to Claim 1, wherein the resin has a modulus of elasticity of 1.5 GPa or less when measured at 25°C in accordance with ASTM D638.

3. The housing for a livestock sensor according to Claim 1 or 2, wherein the resin is a fluororesin.

4. The housing for a livestock sensor according to any one of Claims 1 to 3, wherein the resin is at least one selected from the group consisting of tetrafluoroethylene / perfluoro(alkyl vinyl ether) copolymer, ethylene / tetrafluoroethylene copolymer, tetrafluoroethylene / perfluoroalkyl allyl ether copolymer, and polychlorotrifluoroethylene.

5. The housing for a livestock sensor according to any one of Claims 1 to 3, wherein the resin is a melt-processable fluororesin.

6. The housing for a livestock sensor according to any one of Claims 1 to 5, wherein the resin has a mass change rate of less than 0.5% after being immersed in a 50% by mass formic acid aqueous solution at 50°C for one week.

7. The housing for a livestock sensor according to any one of Claims 1 to 6, wherein the resin has a modulus of elasticity of 440 MPa or more when measured at 25°C in accordance with ASTM D638.

8. A livestock sensor comprising the housing for a livestock sensor according to any one of Claims 1 to 7 and a detection unit housed inside the housing.

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