Tarpaulin and production method of the same

Abstract

To provide a tarpaulin which retains moldability and various performance while having an environmental load reduction effect, and uses for a resin layer, an ether-based thermoplastic polyurethane elastomer using a plant-derived raw material.SOLUTION: In a tarpaulin 1, a resin layer 3 is disposed on at least one surface side of a base fabric 2. The tarpaulin 1 is such that: the resin layer 3 comprises a resin layer composition containing as the main component, an ether-based thermoplastic polyurethane elastomer comprising a reactant of a polyether polyol component, a diisocyanate component and a chain extender component; a plant-derived long chain polyether diol is used as the main component of the polyether polyol component; and an outflow initiation temperature of the resin layer composition, measured under the conditions that a temperature rising speed is 3.0°C / minute by a temperature rising method with an elevated type flow tester, a load is 294.2 N, a diameter of an inner hole of a die is 1.0 mm and a length of the inner hole of the die is 2.0 mm, is 90.0°C or more and 200.0°C or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a tarpaulin in which a thermoplastic polyurethane elastomer made from plant-derived raw materials is used in a resin layer, and a method for producing the same. [Background technology]

[0002] Tarpaulins, which are made by laminating a resin layer onto a woven or knitted base fabric, have excellent waterproof properties and durability, and have traditionally been used in a wide range of applications, including various industrial materials and construction materials such as flexible containers, tents, membrane roofs for structures, partition sheets, banners, and protective sheets, as well as general consumer goods such as rain gear, waterproof clothing, bags, and shoes.

[0003] The resin component used in the resin layer of tarpaulins is mainly soft polyvinyl chloride resin, which is inexpensive and has excellent flexibility and weather resistance. However, soft polyvinyl chloride resin contains a large amount of plasticizer, which can cause problems such as environmental pollution when disposed of or incinerated, problems caused by migration of plasticizers, and concerns about its effects on the human body. Therefore, there is a demand for tarpaulins whose resin layer uses resin components that are less likely to cause such problems and concerns.

[0004] Thermoplastic polyurethane elastomers are free from the various concerns and problems associated with the use of plasticizers as described above, and are also excellent in cold resistance, flexibility, mechanical strength, etc., and polyurethane-processed fabrics using thermoplastic polyurethane elastomers as the resin component of the resin layer have been proposed (Patent Document 1).

[0005] On the other hand, from the perspective of carbon neutrality, which aims to reduce carbon dioxide emissions into the atmosphere as a measure against global warming, the use of biomass has recently been attracting attention again, and efforts are being considered to replace some or all of the conventional petroleum-derived raw materials used in products with plant-derived raw materials, which are raw materials made from biomass such as plants.

[0006] In line with this trend, the replacement of conventional petroleum-derived raw materials with plant-derived raw materials has been considered for the various raw materials used in waterproof fabrics (Patent Document 2). However, if petroleum-derived raw materials are replaced with plant-derived raw materials in an inadvertent manner, there is a risk that the performance of the waterproof fabric may deteriorate or unexpected problems may occur. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2-270520 [Patent Document 2] International Publication No. 2011 / 105595 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in light of these circumstances, and a main object of the present invention is to provide a tarpaulin in which an ether-based thermoplastic polyurethane elastomer made from plant-derived raw materials is used in the resin layer, which has the same or better moldability and various performance properties as tarpaulins in which an ether-based thermoplastic polyurethane elastomer made only from petroleum-derived raw materials is used in the resin layer, and which also has the effect of reducing the environmental load. [Means for solving the problem]

[0009] As a result of investigations into the above-mentioned problems, the present inventors have found that by providing a resin layer on at least one side of a base fabric, the resin layer is made of a resin layer composition containing as a main component an ether-based thermoplastic polyurethane elastomer composed of a reaction product of a polyether polyol component, a diisocyanate component, and a chain extender component, and further using a plant-derived long-chain polyether diol as the main component of the polyether polyol component, and further using a tarpaulin in which the flow start temperature of the resin layer composition is in the range of 90.0°C to 200.0°C, as measured by a heating method using a high-speed flow tester under conditions of a heating rate of 3.0°C / min, a load of 294.2 N, a die inner hole diameter of 1.0 mm, and a die inner hole length of 2.0 mm, it is possible to obtain a tarpaulin that has the same or better moldability and various performance properties as conventional tarpaulins in which an ether-based thermoplastic polyurethane elastomer made solely from petroleum-derived raw materials is used for the resin layer, and that also has the effect of reducing the environmental load. As the plant-derived long-chain polyether diol, it is more preferable to use plant-derived polytrimethylene ether glycol.

[0010] The tarpaulin of the present invention is preferably produced by a manufacturing method including a step of forming a resin layer on at least one side of a base fabric from a resin layer composition having the above-described characteristics by a calendar lamination method. [Effects of the Invention]

[0011] The tarpaulin of the present invention not only has the same molding processability and various performance properties as conventional tarpaulins that use an ether-based thermoplastic polyurethane elastomer made only from petroleum-derived raw materials for the resin layer, but also uses plant-derived raw materials that absorb and fix carbon dioxide from the atmosphere, which means that from a carbon-neutral perspective, it is possible to substantially reduce the amount of carbon dioxide emitted into the atmosphere, thereby contributing to the suppression of carbon dioxide emissions as a measure against global warming and making it possible to reduce the environmental burden. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic cross-sectional view showing an example of an embodiment of the tarpaulin of the present invention. [Figure 2] 1 is a schematic cross-sectional view showing an example of an embodiment of the tarpaulin of the present invention. [Figure 3] 1 is a schematic cross-sectional view showing an example of an embodiment of the tarpaulin of the present invention. [Figure 4] FIG. 2 is a schematic cross-sectional view showing a test piece used for measuring welder peel strength. DETAILED DESCRIPTION OF THE INVENTION

[0013] Details of the tarpaulin and each component of the present invention are given below.

[0014] <<Tarpaulin>> As shown in Fig. 1, the tarpaulin 1 of the present invention has a basic structure including at least a base fabric 2 made of a fiber woven or knitted fabric or the like, and a resin layer 3 laminated on at least one side of the base fabric 2, and as shown in Fig. 2, resin layers (3a, 3b) may be provided on both sides of the base fabric 2. Furthermore, as shown in Fig. 3, an adhesive layer 4 may be provided between the base fabric 2 and the resin layer 3 as needed, and various functional layers such as a printed layer or a protective layer may also be provided on the side of the resin layer 3 opposite to the side facing the base fabric 2.

[0015] The thickness of the tarpaulin of the present invention may be determined arbitrarily depending on the application and required quality, and is not particularly limited, but is preferably in the range of 230 μm or more and 2000 μm or less, and more preferably in the range of more than 300 μm and 1000 μm or less.

[0016] <<Base fabric>> The base fabric of the tarpaulin of the present invention is not particularly limited in terms of weave or structure, as long as it is a fiber woven or knitted fabric conventionally used for this purpose, and woven fabrics such as plain weave, twill weave, and satin weave, as well as various knitted fabrics, can be used. Furthermore, with regard to the material of the base fabric, spun yarns, monofilament yarns, multifilament yarns, blended yarns, and core-sheath yarns made from various natural fibers such as cotton and linen, and synthetic fibers such as polyester resin, polyamide resin, polyolefin resin, polyurethane resin, and polyacrylonitrile resin, can be used. Plain weave fabrics are preferred as the base fabric used in general tarpaulins from the viewpoints of the balance of strength and stretchability in the longitudinal and transverse directions, dimensional stability, and cost. Furthermore, the fiber material and yarn structure used in the base fabric are not particularly limited, but polyester multifilament yarns are preferred from the viewpoints of the heat resistance, strength, and cost of the base fabric, as well as the flexibility, strength, and adhesion to the resin layer when made into a tarpaulin.

[0017] The thickness of the yarns used for the base fabric can be selected appropriately and arbitrarily, taking into account the strength and flexibility of the tarpaulin. For example, when using a plain weave fabric using polyester multifilament yarns as the base fabric, it is preferable to use yarns with a thickness in the range of 200 dtex to 1500 dtex, more preferably in the range of 500 dtex to 1000 dtex, and further to use a plain weave fabric woven so that the density of the warp and weft yarns is in the range of 10 threads / inch to 35 threads / inch, more preferably in the range of 15 threads / inch to 30 threads / inch. The thickness of the base fabric can be selected appropriately and is not particularly limited. However, taking into account the strength, flexibility, durability, and cost of the tarpaulin, it is preferable to use a base fabric with a thickness in the range of 100 μm to 1000 μm. Furthermore, plant-derived materials may be used as the raw material for the fibers constituting the base fabric, as needed, as long as the effects of the present invention are not impaired.

[0018] <<Resin layer>> The resin layer of the tarpaulin of the present invention is a layer laminated on at least one side of the base fabric so as to cover the entire surface of the base fabric, as shown in Figures 1 to 3. The resin layer of the tarpaulin of the present invention is preferably formed by melting and kneading a resin layer composition described below using any of various known kneading devices such as a kneading extruder, mixing roll, Banbury mixer, or pressure kneader, forming the resulting product into a sheet using a method such as a calendar roll or T-die extruder, and then laminating the sheet-like resin layer composition onto the base fabric by any of various methods.

[0019] Examples of methods for laminating a sheet-like resin layer composition formed by a calender roll or the like on one side of a base fabric include, but are not limited to, a thermal lamination method in which the sheet-like resin layer composition is directly laminated on the base fabric, the laminate is heated by some method, and then compressed with a nip roll or the like to laminate, as in the tarpaulin shown in Figure 1, and a dry lamination method in which an adhesive is applied to the base fabric in advance and dried to form an adhesive layer, and the sheet-like resin layer composition is laminated on the side of the base fabric where the adhesive layer is formed, and then compressed with a nip roll or the like to laminate, as in the tarpaulin shown in Figure 3.

[0020] The method for forming the resin layer of the tarpaulin of the present invention is not particularly limited, but when an ether-based thermoplastic polyurethane elastomer is used as the main component of the resin layer composition, as in the tarpaulin of the present invention, it is particularly preferable to use a calendar lamination method, in which the melt-kneaded resin layer composition is first formed into a sheet using a calendar roll, and then the sheet-like resin layer composition is layered on a base fabric and then laminated together to form the resin layer of the tarpaulin. Forming the resin layer of the tarpaulin by the calendar lamination method makes it easy to control the film thickness uniformly and provides excellent formability, thereby improving the productivity of the tarpaulin, and also makes it possible to obtain a tarpaulin having a resin layer made of an imperforate film that is excellent in various mechanical strengths and airtightness.

[0021] The thickness of the resin layer can be determined as appropriate depending on the application and required quality of the tarpaulin, but is preferably in the range of 130 μm to 600 μm, and more preferably in the range of more than 200 μm to 500 μm, taking into consideration the strength, flexibility, durability, and cost of the tarpaulin. The thicknesses of the resin layers provided on both sides of the base fabric may be the same or different. If necessary, after the resin layer is formed on the base fabric, surface treatments such as embossing with an embossing roll or corona treatment may be performed.

[0022] <Resin layer composition> As described above, the resin layer of the tarpaulin of the present invention is formed by adjusting the thickness of a melt-kneaded resin layer composition using a calender roll or the like to form a sheet, which is then laminated on at least one side of a base fabric. Therefore, the melt viscosity characteristics of the resin layer composition significantly affect the molding processability (e.g., ease of melt-kneading and ease of controlling the uniform thickness of the resin layer) and productivity of the resin layer of the tarpaulin of the present invention. Therefore, with regard to the resin layer composition used to form the resin layer of the tarpaulin of the present invention, it is preferable to use a resin layer composition whose flow initiation temperature is in the range of 90.0°C to 200.0°C, and more preferably in the range of 120.0°C to 170.0°C, as measured by a temperature-rising method using a high-speed flow tester under conditions of a temperature rise rate of 3.0°C / min, a load of 294.2 N, a die bore diameter of 1.0 mm, and a die bore length of 2.0 mm. If the outflow start temperature of the resin layer composition is within the above range, melt kneading is easy, and it is easy to mold into a sheet of uniform thickness with few defects using a calendar roll or the like, resulting in good tarpaulin productivity. If the outflow start temperature of the resin layer composition is below the lower limit of the above range, the melt viscosity of the resin layer composition becomes too low or the softening temperature of the resin layer composition is too low, making it difficult to mold into a sheet of uniform thickness, or the sheet after molding tends to stick to the guide roll or break easily. Conversely, if the outflow start temperature of the resin layer composition exceeds the upper limit of the above range, the melt viscosity of the resin layer composition becomes too high or the softening temperature of the resin layer composition is too high. This tends to cause problems such as taking too long to melt knead the resin layer composition or making it difficult to mold into a sheet of uniform thickness when molding the resin layer composition into a sheet. In either case, it has an adverse effect on the molding processability and productivity of the tarpaulin. Furthermore, when considered from the performance standpoint, tarpaulins using a resin layer composition whose flow initiation temperature is below the above range tend to have poor heat resistance and various mechanical strengths, while conversely, tarpaulins using a resin layer composition whose flow initiation temperature is above the above range tend to have poor flexibility.

[0023] The term "Koka flow tester" used in the present invention is a type of capillary rheometer with the same structure as the extrusion plastometer described in JIS K7210-1 (2014), and is characterized by its ability to continuously measure the flow rate of a sample while raising the test temperature at a constant load (temperature-rising method). In the present invention, a "CFT-500D (manufactured by Shimadzu Corporation)" was used as the Koka flow tester for measuring the flow rate. Furthermore, the "flow start temperature" used in the present invention refers to the temperature at which, in measurements using the temperature-rising method using an elevated flow tester, the piston rises slightly due to thermal expansion of the sample in the cylinder, and then the piston clearly begins to descend again. Specifically, when the temperature exceeds the flow start temperature, the sample begins to flow out of the die outlet of the Koka flow tester.

[0024] The tensile strength of the resin layer composition for forming the resin layer of the tarpaulin of the present invention is preferably in the range of 10 MPa or more, and more preferably in the range of 20 MPa or more. If the tensile strength of the resin layer composition is within this range, the mechanical strength against tension of the resin layer of the tarpaulin will be sufficient. Furthermore, the elongation of the resin layer composition is preferably in the range of 300% or more. If the elongation of the resin layer composition is within this range, the strength of the resin layer against bending strain when the tarpaulin is bent, for example, will be sufficient. The tensile strength and elongation of the resin layer composition were measured according to the method described in JIS K7311 (1995).

[0025] The resin layer composition for forming the resin layer of the tarpaulin of the present invention contains, as a resin component, various thermoplastic resins and various thermoplastic elastomers composed of organic polymers, such as an ether-based thermoplastic polyurethane elastomer composed of a reaction product of a polyether polyol component, a diisocyanate component, and a chain extender component, the polyether polyol component being primarily composed of a plant-derived long-chain polyether diol. The resin layer composition of the present invention contains at least the ether-based thermoplastic polyurethane elastomer as a primary component. Other components preferably include various antioxidants to prevent oxidation of the resin component due to heat during melt-kneading or molding, and various lubricants to adjust the melt viscosity and adhesion of the resin layer composition during molding to improve molding processability. Furthermore, various colorant components such as pigments may be added to color the resin layer of the tarpaulin. Furthermore, depending on the application and required quality of the tarpaulin, various additives such as ultraviolet absorbers, ultraviolet reflectors, light stabilizers, heat stabilizers, antistatic agents, flame retardants, antibacterial agents, antiviral agents, and other organic and inorganic fillers may be further added within a range that does not impair the effects of the present invention.

[0026] Next, the various components constituting the resin layer composition and the raw materials constituting the various components will be described in detail.

[0027] <Resin component> The resin layer composition for forming the resin layer of the tarpaulin of the present invention contains at least resin components consisting of various thermoplastic resins made of organic polymers and various thermoplastic elastomers as main components, and the content of the resin components in the resin layer composition is preferably in the range of 80.0 mass% or more of the entire resin layer composition, more preferably in the range of 90.0 mass% or more, and may be 100.0 mass%, taking into account the influence on the various mechanical strengths and various performance properties of the tarpaulin.

[0028] The resin component of the resin layer composition contains at least an ether-based thermoplastic polyurethane elastomer as the main component, which uses a plant-derived long-chain polyether diol as the main component of the polyether polyol component, and the content of the ether-based thermoplastic polyurethane elastomer in the resin component is preferably 90.0% by mass or more, more preferably 95.0% by mass or more, and most preferably the resin component is composed solely of the ether-based thermoplastic polyurethane elastomer. The resin component may further contain small amounts of various other known thermoplastic resins or other thermoplastic elastomers as needed, provided that the effects of the present invention are not impaired, but the content of the ether-based thermoplastic polyurethane elastomer in the resin component is preferably at most 10.0% by mass, more preferably at most 5.0% by mass.

[0029] <Ether-based thermoplastic polyurethane elastomer> Thermoplastic polyurethane elastomers are polyurethane-based polymers that possess the properties of both thermoplastics and rubber. They soften when heated, exhibiting thermoplastic properties that allow them to be molded, and exhibit rubber-like elasticity when cooled to room temperature. Thermoplastic polyurethane elastomers are generally linear polymers composed of the reaction product of a polymer polyol component, a diisocyanate component, and a chain extender component, and are characterized by the presence within their molecular structure of soft segments primarily composed of the polymer polyol component and the diisocyanate component, and hard segments primarily composed of the diisocyanate component and the chain extender component. The "ether-based thermoplastic polyurethane elastomer using a plant-derived long-chain polyether diol as the main component of the polyether polyol component" that can be suitably used as the main component of the resin layer composition for forming the resin layer of the tarpaulin of the present invention refers to an ether-based thermoplastic polyurethane elastomer that uses only a polyether polyol component composed of polyether polyol as the polymer polyol component of the thermoplastic polyurethane elastomer described above, and is further characterized by using a plant-derived long-chain polyether diol as the main component of the polyether polyol component.

[0030] The resin layer composition for forming the resin layer of the tarpaulin of the present invention contains, as a main component, an ether-based thermoplastic polyurethane elastomer using at least a plant-derived long-chain polyether diol as the main component of the polyether polyol component, and the content of the ether-based thermoplastic polyurethane elastomer in the resin layer composition is preferably in the range of 80% by mass or more, more preferably in the range of 90.0% by mass or more, and may be 100.0% by mass.

[0031] The resin layer composition for forming the resin layer of the tarpaulin of the present invention contains, as a main component, an ether-based thermoplastic polyurethane elastomer in which a plant-derived long-chain polyether diol is used as the main component of the polyether polyol component, and therefore the melt viscosity characteristics of the ether-based thermoplastic polyurethane elastomer significantly affect the melt viscosity characteristics of the resin layer composition. Therefore, the ether-based thermoplastic polyurethane elastomer that can be suitably used in the present invention is one whose flow initiation temperature is preferably between 90.0°C and 200.0°C, more preferably between 120.0°C and 170.0°C, as measured by a temperature-rising method using a Koka flow tester under conditions of a temperature rise rate of 3.0°C / min, a load of 294.2 N, a die bore diameter of 1.0 mm, and a die bore length of 2.0 mm.

[0032] The glass transition temperature of the ether-based thermoplastic polyurethane elastomer, which uses a plant-derived long-chain polyether diol as the main component of the polyether polyol component suitable for use in the resin layer of the present invention, is preferably in the range of -30.0°C or lower, and more preferably in the range of -40.0°C or lower. If the glass transition temperature of the ether-based thermoplastic polyurethane is within the above range, it is possible to obtain a tarpaulin with excellent flexibility and cold resistance. The glass transition temperature was measured using a differential scanning calorimeter (DSC method).

[0033] (Polyether polyol component) The ether-based thermoplastic polyurethane elastomer used as the main component of the resin layer composition for forming the resin layer of the tarpaulin of the present invention is an ether-based thermoplastic polyurethane elastomer that uses only a polyether polyol component composed of a polyether polyol as the polymer polyol component for constituting the soft segment of the thermoplastic polyurethane elastomer. The polyether polyol component preferably contains, as at least a long-chain polyether diol having a number-average molecular weight (Mn) of several hundred to several thousand as the main component, and more preferably is composed solely of the long-chain polyether diol. The long-chain polyether diol that can be suitably used in the present invention is preferably a polyalkylene ether glycol, which is a linear polymer having alkylene ether repeating units in its structure. Specific examples include polyethylene glycol, polypropylene glycol, polytrimethylene ether glycol, polytetramethylene ether glycol, and polyhexamethylene ether glycol. One or more long-chain polyether diols selected from the group consisting of the various long-chain polyether diols listed above can be used.

[0034] On the other hand, in order to achieve the object of the present invention, a thermoplastic polyurethane elastomer using plant-derived raw materials must be used in the resin layer composition for forming the resin layer of the tarpaulin, but if the petroleum-derived raw materials used in the thermoplastic polyurethane elastomer are carelessly replaced with plant-derived raw materials, various performance properties of the tarpaulin may deteriorate and unexpected problems may occur. Therefore, as a result of intensive research, the present inventors have found that by using only a polyether polyol component as the polymer polyol component of the thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin, and by containing a plant-derived long-chain polyether diol as the main component in this polyether polyol component, it is possible to suppress the deterioration of various performance properties of the tarpaulin and the occurrence of problems as described above.

[0035] Examples of plant-derived long-chain polyether diols that can be suitably used as the main component of the polyether polyol component of the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention include plant-derived polyethylene glycol, plant-derived polypropylene glycol, plant-derived polytrimethylene ether glycol, plant-derived polytetramethylene ether glycol, and plant-derived polyhexamethylene ether glycol, and it is possible to use one or more plant-derived long-chain polyether diols selected from the group of the various plant-derived long-chain polyether diols mentioned above. The aforementioned long-chain polyether diols derived from various plants are obtained by first preparing monomers such as plant-derived ethylene glycol, plant-derived 1,2-propanediol, plant-derived 1,3-propanediol, plant-derived 1,4-butanediol, plant-derived 1,6-hexanediol, or derivatives of the aforementioned plant-derived glycols by subjecting biomass such as sugarcane or corn to microbial fermentation or various chemical reaction processes, and then polymerizing the monomers as necessary. The polyether polyol component of the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention preferably uses as its main component the aforementioned long-chain polyether diols derived from various plants. However, the content of the plant-derived long-chain polyether diol in the polyether polyol component is preferably 80% by mass or more, more preferably 90% by mass or more, and may even be 100% by mass of plant-derived long-chain polyether diols. As the polyether polyol component other than the plant-derived long-chain polyether diol contained in the polyether polyol component, it is preferable to use various petroleum-derived long-chain polyether diols.

[0036] As a result of further investigations, the inventors have found that by using plant-derived polytrimethylene ether glycol, which is produced by condensation polymerization of plant-derived 1,3-propanediol, which is produced by fermenting starch from plants such as corn using microorganisms, among plant-derived long-chain polyether diols, as the main component of the polyether polyol component of the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention, not only do the unexpected problems described above not occur, but the moldability and various performance properties tend to be improved compared to tarpaulins using an ether-based thermoplastic polyurethane elastomer made only from petroleum-derived raw materials for the resin layer.

[0037] When plant-derived polytrimethylene ether glycol is used as the main component of the polyether polyol component of the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention, the content of plant-derived polytrimethylene ether glycol in the polyether polyol component is preferably 80% by mass or more, more preferably 90% by mass or more, and may even be 100% by mass of plant-derived polytrimethylene ether glycol. The polyether polyol component other than plant-derived polytrimethylene ether glycol preferably includes the various plant-derived long-chain polyether diols mentioned above other than plant-derived polytrimethylene ether glycol or various petroleum-derived long-chain polyether diols. The number-average molecular weight of the plant-derived polytrimethylene ether glycol used as the main component of the polyether polyol component of the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention is not particularly limited, but it is preferable to use one with a number-average molecular weight of 1,000 to 3,000.

[0038] The content of the polyether polyol component in the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention is preferably in the range of 40.0 to 75.0% by mass, more preferably in the range of 50.0 to 65.0% by mass. If the content of the polyether polyol component in the ether-based thermoplastic polyurethane elastomer is below the lower limit of the above range, the proportion of soft segments will be reduced, which will result in the flow-initiating temperature of the ether-based thermoplastic polyurethane elastomer becoming too high, thereby degrading the moldability of the resin layer composition, or the ether-based thermoplastic polyurethane elastomer becoming too hard, which will likely result in a loss of flexibility of the tarpaulin. Conversely, if the content of the polyether polyol component in the ether-based thermoplastic polyurethane elastomer is above the upper limit of the above range, the proportion of soft segments will be too high, which will result in the flow-initiating temperature of the ether-based thermoplastic polyurethane elastomer becoming too low, thereby degrading the moldability of the resin layer composition, or poor heat resistance and various mechanical strengths of the tarpaulin.

[0039] The lower limit of the content of the plant-derived long-chain polyether diol in the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention must be at least 20.0% by mass, preferably 40.0% by mass or more, and more preferably 50.0% by mass or more. Conversely, the upper limit of the content of the plant-derived long-chain polyether diol in the ether-based thermoplastic polyurethane elastomer is the same as the upper limit of the polyether polyol component described above, and is preferably 75.0% by mass or less, and more preferably 65.0% by mass or less.

[0040] When plant-derived polytrimethylene ether glycol is used as the main component of the polyether polyol component of the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention, the content of plant-derived polytrimethylene ether glycol in the ether-based thermoplastic polyurethane elastomer must be at least 20.0 mass% or more, similar to the plant-derived long-chain polyether diol described above, preferably in the range of 40.0 mass% or more and 75.0 mass% or less, and more preferably in the range of 50.0 mass% or more and 65.0 mass% or less.

[0041] (Diisocyanate component) The diisocyanate component, which is one of the raw materials of the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention, is an organic compound having two isocyanate groups in its molecular structure, and generates molecular chains of the ether-based thermoplastic polyurethane elastomer by reacting with the other raw materials, the polyether polyol component and the chain extender component, and polymerizing them. The diisocyanate component of the ether-based thermoplastic polyurethane elastomer used in the present invention is not particularly limited, and examples thereof include various aliphatic isocyanates such as 1,4-tetramethylene diisocyanate, 1,5-pentane diisocyanate, and 1,6-hexamethylene diisocyanate (abbreviated as HDI), various alicyclic diisocyanates such as isophorone diisocyanate (abbreviated as IPDI) and dicyclohexylmethane-4,4'-diisocyanate (abbreviated as H12MDI), and 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, and 4,4'-diphenylmethane diisocyanate. One or more diisocyanates selected from a group of various known diisocyanates can be used as the diisocyanate component, such as diphenylmethane diisocyanate (abbreviated as MDI), tolylene diisocyanate (abbreviated as TDI), which includes 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, and various aromatic diisocyanates such as m-xylylene diisocyanate (abbreviated as XDI). However, it is particularly preferred to use diphenylmethane diisocyanate as the main component of the diisocyanate component, and it is more preferred to use only diphenylmethane diisocyanate as the diisocyanate component. Note that, for the diisocyanate component, petroleum-derived diisocyanates or plant-derived diisocyanates may be used, but petroleum-derived diisocyanates are more preferred.

[0042] (Chain extender component) The chain extender component, which is one of the raw materials for the ether-based thermoplastic polyurethane elastomer used in the resin layer composition for forming the resin layer of the tarpaulin of the present invention, is preferably composed mainly of a linear alkanediol, and if necessary, a branched alkanediol or a cyclic alkanediol may be used in addition to the linear alkanediol that is the main component, but it is most preferable that it consists only of a linear alkanediol. Examples of linear alkanediols suitable for use as chain extenders in the present invention include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and 1,12-dodecanediol. While one or more linear alkanediols selected from the above-listed linear alkanediols can be used as the chain extender component of the present invention, it is particularly preferred to use 1,4-butanediol as the main component of the chain extender component, and more preferably to use only 1,4-butanediol as the chain extender component. The chain extender component may be derived from either petroleum or plant, with petroleum-derived alkanediols being more preferred.

[0043] <Lubricant ingredients> It is preferable to further add a lubricant component to the resin layer composition for forming the resin layer of the tarpaulin of the present invention for the purpose of improving ease of melt kneading and ease of molding of the resin layer composition by adjusting the melt viscosity of the resin layer composition or improving the releasability of the resin layer composition from a calender roll, etc. The lubricant component used in the present invention is not particularly limited and various known lubricants can be used.Specific examples include various hydrocarbon waxes such as paraffin wax, polyethylene wax, Fischer-Tropsch wax, and microcrystalline wax, higher fatty acids such as oleic acid and stearic acid, various fatty acid esters such as oleic acid esters, stearic acid esters, and montanic acid esters, various glycerin fatty acid esters such as stearic acid monoglyceride, various fatty acid amides such as stearic acid amide and ethylene bisstearic acid amide, and various metal soaps such as zinc stearate and calcium stearate.One or more lubricants selected from the group of various known lubricants can be suitably used.

[0044] The content of the lubricant component in the resin layer composition of the present invention is preferably a mass ratio of 0.05 to 3.00 parts by mass, more preferably a mass ratio of 0.10 to 2.00 parts by mass, relative to 100.00 parts by mass of the resin component in the resin layer composition. If the content of the lubricant component in the resin layer composition is within the above range, the molding processability of the resin layer composition will be good.

[0045] <Antioxidant ingredients> It is preferable to further add an antioxidant component to the resin layer composition used to form the resin layer of the tarpaulin of the present invention, for the purpose of suppressing oxidative deterioration of the resin component of the resin layer composition due to heat during molding. The antioxidant component used in the present invention is not particularly limited, and various known antioxidants can be used, and specifically, phenol-based antioxidants and phosphite-based antioxidants can be preferably used.

[0046] The content of the antioxidant component in the resin layer composition of the present invention is preferably a mass ratio of 0.05 to 1.00 parts by mass, more preferably a mass ratio of 0.10 to 0.50 parts by mass, relative to 100.00 parts by mass of the resin component in the resin layer composition. When the content of the antioxidant component in the resin layer composition is within the above range, it is possible to sufficiently suppress oxidative degradation due to heat during molding and processing of the resin layer composition.

[0047] <<Adhesive layer>> The tarpaulin of the present invention may optionally have an adhesive layer between the base fabric and the resin layer. In particular, when the resin layer is provided on only one side of the base fabric, the adhesive strength between the base fabric and the resin layer may be insufficient compared to when the resin layer is provided on both sides of the base fabric. Therefore, it is preferable to provide the adhesive layer by selecting various adhesives depending on the application and required quality. The type of adhesive and lamination method are not particularly limited, and adhesives such as those for dry lamination, wet lamination, and hot melt lamination can be used. Furthermore, the adhesive may or may not contain a crosslinking agent component, but it is preferable for it to contain a crosslinking agent component to improve the adhesion between the base fabric and the resin layer. The composition of the adhesive's main agent is not particularly limited; the type of adhesive's main agent can be selected depending on the combination of the base fabric and the resin layer. However, it is preferable to use one of polyester-based adhesives, polyurethane-based adhesives, and polyester urethane-based adhesives. The amount of adhesive applied and the method for forming the adhesive layer are not particularly limited. The adhesive layer may be formed by applying a small amount of adhesive to the surface of the base fabric using a gravure roll or the like and then drying, or the adhesive layer may be formed by impregnating the base fabric with adhesive and then drying.

[0048] <Bio-based mass content> When assessing the environmental impact reduction effect of the tarpaulin of the present invention, it is preferable to use the biobased mass content defined in ISO 16620-1, 4. The biobased mass content is the ratio of the total mass of biomass-derived (including plant-derived) components contained in the raw material divided by the total mass of the raw material. The biobased mass content of the tarpaulin of the present invention is not particularly limited, but must be at least 10.0% or more, preferably 25.0% or more, more preferably 50.0% or more, and most preferably 85.0% or more in terms of environmental impact reduction effect. To achieve a biobased mass content within the above range, the biobased mass content of the resin layer composition used to form the resin layer of the tarpaulin of the present invention is preferably 30.0% or more. Similarly, the biobased mass content of the ether-based thermoplastic polyurethane elastomer, which uses a plant-derived long-chain polyether diol as the main component of the polyether polyol component used in the resin layer composition of the present invention, is preferably 40.0% or more. Other indices that can be used to consider these environmental load reduction effects include the "bio-based carbon content (ISO16620-1, 2)," which analyzes the ratio of carbon isotopes contained in the raw material and calculates the proportion of bio-based carbon in the total carbon in the raw material based on the results, and the "biomass plastic degree (ISO16620-1, 3)," which is the ratio obtained by dividing the total mass of biomass-derived components in the biomass plastic contained in the raw material by the total mass of the raw material; and these other indices may also be used depending on the content of the study. [Example]

[0049] The present invention will now be described in detail with reference to examples, but is not limited to these examples. In the tables of examples, "thermoplastic polyurethane elastomer" may be abbreviated as "TPU."

[0050] <<How to make tarpaulin>> <Base fabric> The base fabric used for the tarpaulin of the example was a polyester plain weave fabric using 560 dtex polyester multifilament yarn, with a count density of 19 warp threads / inch and 20 weft threads / inch, a thickness of 220 μm, and a basis weight of 88.0 g / m2.

[0051] <Resin layer composition> Information on the various properties and components of the various ether-based thermoplastic polyurethane elastomers used as resin components in the resin layer compositions for forming the resin layers of the tarpaulins of the examples of the present invention is shown in Table 1. Table 2 also shows the raw material blending ratios of the resin layer compositions used in the examples.

[0052] [Table 1]

[0053] Among the various ether-based thermoplastic polyurethane elastomers TPU1 to TPU5 used in the examples shown in Table 1, TPU1 to TPU4 are ether-based thermoplastic polyurethane elastomers in which all polyether polyol components are plant-derived long-chain polyether diols (specifically, all polyether polyol components are plant-derived polytrimethylene ether glycol), but the content of plant-derived long-chain polyether diol in each ether-based thermoplastic polyurethane elastomer differs. On the other hand, TPU5 is a general ether-based thermoplastic polyurethane elastomer in which all polyether polyol components are petroleum-derived polytetramethylene ether glycol. Furthermore, TPU1 to TPU5 have in common that the diisocyanate component is petroleum-derived diphenylmethane diisocyanate and the chain extender component is petroleum-derived 1,4-butanediol.

[0054] [Table 2]

[0055] <Preparation of sheet-shaped resin layer composition (melt kneading / calender molding)> The various raw materials for each resin layer composition described above were blended in the blending ratios shown in Table 2 and melt-kneaded for 10 minutes using a mixing roll set at a temperature of 150 to 190°C. Subsequently, using a test calender roll device, the uniformly melt-kneaded resin layer composition was passed through a calender roll set at a temperature of 150 to 190°C to form a sheet with a thickness of 210±5 μm. This was then laminated on a sheet of forming paper and removed through a nip roll. The results of measurements of various property values ​​and evaluations of the removed sheet-like resin layer composition are shown in Table 2. The set temperatures of the mixing roll during melt-kneading of each resin layer composition and the set temperatures of the calender roll during calendering of each resin layer composition when producing the sheet-like resin layer composition are shown in Table 3.

[0056] <Production of tarpaulin for evaluation (melt kneading / calender molding / thermal lamination)> Each resin layer composition was melt-kneaded under the same conditions as described above and passed through a calender roll to form a sheet having a thickness of 210±5 μm. The molten resin layer composition was then laminated on a base fabric made of the above-mentioned polyester plain weave fabric and then removed through a nip roll to form a resin layer on one side of the base fabric. Next, the resulting laminate consisting of the base fabric and resin layer was pressed in a sheet press at a temperature of 150 to 190°C and a surface pressure of 30 kgf / cm. 2 The base fabric and the resin layer were then heat-pressed for 1 minute under these conditions to perform a thermal lamination process, firmly bonding the base fabric and the resin layer together. A resin layer was then formed on the other side of the base fabric in the same manner, and the same thermal lamination process was performed to produce the tarpaulins used for evaluation in the examples of the present invention. The total thickness of each tarpaulin produced was in the range of 530±30 μm. Table 3 shows the set temperatures of the mixing roll during melt-kneading of each resin layer composition, the set temperatures of the calendar roll during calendar molding of each resin layer composition, and the set temperatures of the sheet press machine during thermal lamination of the base fabric and each resin layer (each resin layer composition) when producing each tarpaulin for evaluation.

[0057] [Table 3]

[0058] <<Various measurement and evaluation methods for tarpaulins>> The tarpaulins used in the examples were prepared using the method described above, and various properties were measured and evaluated using the methods described below. The results are shown in Table 4. In order to solve the problems of the present invention, it is desirable for the tarpaulins to be rated A or B in each of the following evaluations.

[0059] (Measurement of tensile strength and elongation of tarpaulin) The tensile strength and elongation of the tarpaulin were measured using the strip method described in JIS L 1096. The test pieces were prepared by first taking samples with the warp and weft directions of the tarpaulin base fabric as the length direction, adjusting them into rectangular test pieces 30 mm wide x 300 mm long, and then setting them in a tensile tester with a grip separation of 200 mm. The tensile test was carried out at a pulling speed of 200 mm / min, thereby measuring the tensile strength (N) and elongation (%) of the tarpaulin.

[0060] (Evaluation of tarpaulin molding processability) Of the factors that have a significant effect on the molding processability of tarpaulin, we focused on two factors: (1) the ease of melt-kneading the resin layer composition, and (2) the ease of molding the resin layer composition into a sheet. We evaluated the molding processability of tarpaulin according to the following evaluation criteria. A: There are no particular problems with the melt-kneading and molding of the resin layer composition, and the molding processability of the tarpaulin is good. B: There are some difficulties in at least one of melt-kneading and molding of the resin layer composition, but this does not pose a problem in molding the tarpaulin. C: There is a major problem with at least one of the melt-kneading and molding processes of the resin layer composition, making it difficult to carry out molding processes of the tarpaulin.

[0061] (Measurement of tarpaulin stiffness and evaluation of flexibility) The tarpaulin was cut into a rectangular shape of 20 mm wide x 150 mm long, with the warp direction of the tarpaulin base fabric as the length direction, to prepare a test specimen. The bending resistance of the prepared test specimen was measured according to the 45° cantilever method described in JIS L1096. The bending resistance (mm) measured using the 45° cantilever method was measured. Based on the bending resistance measurement results of each tarpaulin, the flexibility of the tarpaulin was evaluated according to the evaluation criteria shown below. A: Less than 80.0 mm B: 80.0 mm or more and less than 100.0 mm C...100.0mm or more

[0062] (Evaluation of Tarpaulin Abrasion Resistance) The tarpaulin was fixed to the test piece stand of a Gakushin friction tester (type II friction tester), and a friction element equipped with white cotton cloth (No. 3 gold cloth) specified in JIS L0803 was used to rub the white cotton cloth and the resin layer of the tarpaulin back and forth 1000 times under a load of 200 gf to test the abrasion resistance. After the test, the condition of the surface of the tarpaulin was visually observed, and the abrasion resistance of the tarpaulin was evaluated according to the evaluation criteria shown below. A: The resin layer is not worn at all. B: Faint scratches may be seen on the surface of the resin layer. C: Clear scratches are visible on the surface of the resin layer.

[0063] (Measurement of tarpaulin welder peel strength and evaluation of welder suitability) Two rectangular test pieces, each 30 mm wide and 100 mm long, were cut from the tarpaulin, with the warp direction of the tarpaulin base fabric as the length direction. As shown in Figure 4, the two test pieces (5a, 5b) were stacked together, and the welder blade of a high-frequency welder was applied to one end of the test piece to weld a 5 mm long x full-width portion of the test piece (high-frequency welder welded portion (6a, 6b)). This produced test piece 7 for measuring welder peel strength. The high-frequency welder used was a "YO-5A" model manufactured by Yamamoto Vinita Co., Ltd., and welding was performed under the following conditions: welding time: 10 seconds, cooling time: 4 seconds, platen temperature: 60°C, anode current: 0.25±0.02 A.

[0064] For the welder peel strength measurement test pieces prepared by the method described above, the other end of test piece 5a and test piece 5b, opposite the end with the high-frequency welder weld, were each fixed to the chuck of a tensile tester. The high-frequency welder weld was set so that it was centered between the chucks of the tensile tester. The welder peel strength measurement test piece set in the tensile tester was pulled in the direction shown in Figure 4 with a grip distance of 100 mm and a pulling speed of 50 mm / min, and the tensile strength (N) was measured when the high-frequency welder weld peeled. Based on the measured welder peel strength results, the tarpaulin's weldability was evaluated according to the evaluation criteria shown below. A...400.0N or more B: 300.0N or more but less than 400.0N C Less than 300.0N

[0065] [Table 4]

[0066] From the various property values ​​and the results of various evaluations of the various tarpaulins in Table 4, it can be seen that, like the tarpaulins of Examples 1 to 4, a resin layer is provided on at least one side of the base fabric, and the resin layer is made of a resin layer composition containing, as a main component, an ether-based thermoplastic polyurethane elastomer consisting of a reaction product of a polyether polyol component, a diisocyanate component, and a chain extender component, and further, a plant-derived long-chain polyether diol is used as the main component of the polyether polyol component, and further, in a temperature rise method using a high-temperature flow tester, the temperature rise rate is 3.0°C / min, the load is 294.2N, the diameter of the die inner hole is 1.0mm, and the length of the die inner hole is 2.0mm. If the resin layer composition has a flow start temperature measured under the above conditions in the range of 90.0°C or higher and 200.0°C or lower, the "moldability" will be equal to or better than conventional tarpaulins that use an ether-based thermoplastic polyurethane elastomer made only from petroleum-derived raw materials in the resin layer, such as the tarpaulin of Reference Example 1, and various performance characteristics such as "tarpaulin tensile strength / elongation," "tarpaulin flexibility," "tarpaulin abrasion resistance," and "tarpaulin welder suitability" will also be equal to or better than those of conventional tarpaulins that use an ether-based thermoplastic polyurethane elastomer made only from petroleum-derived raw materials in the resin layer, and furthermore, the use of plant-derived raw materials in the resin layer will result in a reduction in environmental impact. [Industrial Applicability]

[0067] The tarpaulin of the present invention can be used for tents, flexible containers, membrane roofs for structures, banners, protective sheets, waterproof sheets, waterproof sheets, raincoats, shoes, bags, backpacks, various cases, various bags, various lifesaving equipment, air ducts, curtains, partition sheets, as well as various construction materials and various civil engineering materials. [Explanation of symbols]

[0068] 1; Tarpaulin 2; Base fabric 3: Resin layer 3a; resin layer 3b;Resin layer 4;Adhesive layer 5a: Tarpaulin test piece 5b: Tarpaulin test piece 6a: High frequency welder welded part 6b: High frequency welder welded part 7: Test piece for measuring welder peel strength

Claims

1. A tarpaulin having a resin layer provided on at least one side of a base fabric, the resin layer is made of a resin layer composition containing, as a main component, an ether-based thermoplastic polyurethane elastomer formed from a reaction product of a polyether polyol component, a diisocyanate component, and a chain extender component; a plant-derived long-chain polyether diol is used as a main component of the polyether polyol component; A tarpaulin in which the flow-out start temperature of the resin layer composition is in the range of 90.0°C or higher and 200.0°C or lower, as measured by a temperature rise method using a high-speed flow tester under the conditions of a temperature rise rate of 3.0°C / min, a load of 294.2 N, a diameter of the die inner hole of 1.0 mm, and a length of the die inner hole of 2.0 mm.

2. 2. The tarpaulin according to claim 1, wherein the plant-derived long-chain polyether diol is plant-derived polytrimethylene ether glycol.

3. 3. The tarpaulin according to claim 2, wherein the resin layer composition contains a lubricant component in a range of 0.05 parts by mass or more and 3.00 parts by mass or less and an antioxidant component in a range of 0.05 parts by mass or more and 1.00 parts by mass or less, relative to 100.00 parts by mass of the resin component.

4. The tarpaulin according to claim 3, wherein the content of plant-derived polytrimethylene ether glycol in the ether-based thermoplastic polyurethane elastomer is in the range of 40.0% by mass or more and 75.0% by mass or less.

5. The tarpaulin according to any one of claims 1 to 4, wherein diphenylmethane diisocyanate is used as a main component of the diisocyanate component.

6. The tarpaulin according to any one of claims 1 to 4, wherein 1,4-butanediol is used as a main component of the chain extender component.

7. 5. The tarpaulin according to any one of claims 1 to 4, wherein the flow initiation temperature of the ether-based thermoplastic polyurethane elastomer is measured by a temperature rise method using a Koka type flow tester under conditions of a temperature rise rate of 3.0°C / min, a load of 294.2 N, a die inner hole diameter of 1.0 mm, and a die inner hole length of 2.0 mm, in the range of 90.0°C or higher and 200.0°C or lower.

8. The tarpaulin according to any one of claims 1 to 4, wherein the resin layer composition has a tensile strength in the range of 10 MPa or more and an elongation in the range of 300% or more.

9. The tarpaulin according to any one of claims 1 to 4, wherein the bio-based mass content of the ether-based thermoplastic polyurethane elastomer is in the range of 40.0% or more.

10. The tarpaulin according to any one of claims 1 to 4, wherein the thickness of the resin layer is in the range of 130 µm or more and 600 µm or less.

11. A method for producing a tarpaulin, comprising a step of forming a resin layer from a resin layer composition by a calendar lamination method on at least one side of a base fabric, the resin layer is made of a resin layer composition containing, as a main component, an ether-based thermoplastic polyurethane elastomer formed from a reaction product of a polyether polyol component, a diisocyanate component, and a chain extender component; a plant-derived long-chain polyether diol is used as a main component of the polyether polyol component; A method for producing a tarpaulin, wherein the resin layer composition has an outflow start temperature in the range of 90.0°C or higher and 200.0°C or lower, measured by a temperature rise method using a high-speed flow tester under the conditions of a temperature rise rate of 3.0°C / min, a load of 294.2 N, a die inner hole diameter of 1.0 mm, and a die inner hole length of 2.0 mm.

12. The method for producing a tarpaulin according to claim 11, wherein the plant-derived long-chain polyether diol is plant-derived polytrimethylene ether glycol.

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