JP4955074B2 - Fuel container with excellent gasoline barrier properties - Google Patents

Description

  The present invention relates to a fuel container having a high gasoline barrier property.

  As a container for storing hydrocarbons such as gasoline, a plastic co-extrusion blow-molded container has been suitably used in recent years, and an example thereof is an automobile fuel tank. In addition, polyethylene (especially ultra-high density polyethylene) is expected as a plastic in terms of economy, moldability, mechanical strength, and the like. However, polyethylene fuel tanks are known to have the disadvantage that stored gasoline gases or liquids tend to volatilize into the atmosphere through the polyethylene walls of the container.

Therefore, in order to eliminate such drawbacks, a method has been disclosed in which halogen gas (fluorine, chlorine, bromine) or sulfur trioxide (SO ₃ ) or the like is blown into a polyethylene container to halogenate or sulfonate the inner surface of the container. Yes. Moreover, the method of multilayering a polyamide resin and a polyethylene resin is disclosed (Patent Document 1, Patent Document 2). In addition, a method of multilayering an ethylene-vinyl alcohol copolymer (EVOH) resin and a polyethylene resin is also known (Patent Document 3 and Patent Document 4). Moreover, in order to improve gasoline barrier property, the multilayer fuel tank which made the barrier layer near inner layer is also known (patent document 5, patent document 6).

  However, even in the fuel container manufactured by the above method, the control of the gasoline permeation amount is not perfect. In recent years, the method of reducing the permeation amount to save gasoline consumption, improve performance, and protect the global environment. Is desired.

  Moreover, the fuel tank for motor vehicles is mentioned as a suitable aspect of the said fuel container. In general, a fuel tank for an automobile must be connected to a fuel filler port, an engine, a canister, and the like through piping. For this reason, in order to connect the tank and various pipes, it is possible to provide an opening in the body of the tank body and to attach fuel container accessories (such as a fuel tank connector) for joining the tank and the various pipes. Many. Conventionally, most of the fuel container accessory parts are made of high-density polyethylene, and until now, the amount of fuel permeated from the fuel container accessory parts has never been a problem.

  However, the level required to suppress the amount of fuel permeated from the fuel container has been increasing in recent years. Accordingly, the present inventors have conducted detailed studies with the aim of reducing the amount of fuel permeation at the mounting portion of the fuel container accessory.

  As a result, the present inventors have developed an accessory for a fuel tank made of a resin composition containing EVOH (Japanese Patent Application Nos. 11-172151 and 11-172152). A significant reduction in fuel permeation was achieved.

  However, the gasoline barrier obtained by calculation in consideration of the difference between the gasoline barrier property possessed by the resin composition containing EVOH and the gasoline barrier property possessed by the high-density polyethylene conventionally used as a material for fuel container accessories. The improvement effect of the gasoline barrier property actually obtained with respect to the improvement effect of the property was smaller than the calculated value.

JP-A-6-134947 US Pat. No. 5,447,781 US Pat. No. 5,849,376 European Patent Application Publication No. 759359 JP-A-9-29904 European Patent Application Publication No. 742096 US Pat. No. 2,495,286 JP-A-53-128690 JP 59-197427 A JP 61-91226 A JP 62-232434 A JP-A-62-53332 JP-A-63-3025 JP-A 63-105031 JP-A 63-154737 Japanese Patent Laid-Open No. 1-149829 JP-A-1-201333 JP-A-2-67319

  The present invention provides a fuel container having a high gasoline barrier property.

  In the fuel container having a layer made of the barrier resin (A) and an outer layer made of the thermoplastic resin (B) other than (A) and having an opening in the container body, The problem is also solved by a fuel container characterized in that a groove is provided on the outer peripheral surface and the inner surface of the groove is covered with a barrier material (C).

  Furthermore, in the fuel container having a layer made of the barrier resin (A) and an outer layer made of the thermoplastic resin (B) other than (A), and having an opening in the container body, the opening This is also solved by a fuel container, characterized in that a groove is provided on the outer surface around and the groove is filled with a barrier material (C).

  In a preferred embodiment, the fuel container according to the present invention has a fuel container accessory attached to an opening provided in the body.

  In a preferred embodiment, the groove provided on the outer surface around the opening provided in the container body of the fuel container of the present invention is filled with the fuel container accessory made of the barrier material (C). .

  In a preferred embodiment, the groove provided on the outer surface around the opening provided in the container body of the fuel container of the present invention surrounds the opening without interruption. More preferably, the shape of the groove is circular.

  In a preferred embodiment, the depth of the groove is 0.1 to 0.8 times the container body average total layer thickness (T2). In addition, an embodiment in which the depth of the groove is 0.2 times or more and less than 1 times the total thickness (T1) of the layers existing outside the layer made of the barrier resin (A) is also preferable.

  Moreover, in a suitable embodiment, the width | variety of a groove | channel is 0.01-5 times the container trunk | drum average whole layer thickness (T2).

In a preferable embodiment, the gasoline permeation amount of the barrier resin (A) used in the present invention is 100 g · 20 μ / m ² · day (value measured at 40 ° C.-65% RH) or less.

  In a preferred embodiment, the barrier resin (A) used in the present invention is at least one selected from the group consisting of polyvinyl alcohol resins, polyamides, and aliphatic polyketones.

  Furthermore, in a preferred embodiment, in the fuel of the present invention, the thermoplastic resin (B) constituting the inner layer is a polyolefin, and preferably a polyethylene having a density of 0.93 or more.

  In a preferred embodiment, the gasoline permeation amount (measured at 40 ° C.-65% RH) of the barrier material (C) used in the present invention is the gasoline permeation amount (40 ° C.-65% RH) of the thermoplastic resin (B). The measured value is 0.1 times or less.

Moreover, in a preferable embodiment, the gasoline permeation amount of the barrier material (C) used in the present invention is 400 g · 20 μ / m ² · day (a value measured at 20 ° C.-65% RH) or less.

  Furthermore, in a preferred embodiment, the barrier material (C) used in the present invention is at least one selected from the group consisting of metal foil, epoxy resin, polyvinylidene chloride resin, polyvinyl alcohol resin, polyamide resin, polyester resin, and fluororesin. It is a seed.

  In a preferred embodiment, the fuel container of the present invention has an intermediate layer made of a barrier resin (A) and inner and outer layers made of a thermoplastic resin (B) other than (A).

  In a preferred embodiment, the fuel container of the present invention is formed by laminating a layer made of a barrier resin (A) and a layer made of a thermoplastic resin (B) other than (A) through an adhesive resin layer.

  In a preferred embodiment, the fuel container of the present invention has a ratio of the total thickness (T1) and the total thickness (T2) of the layers existing outside the layer made of the barrier resin (A) in the container body ( T1 / T2) is 45/100 or less.

  A fuel container having a high gasoline barrier property can be provided. In a preferred embodiment, it is possible to exhibit an excellent gasoline barrier property even in a fuel container in which an accessory part for a fuel container is attached to an opening provided in the container body part. More preferably, the gasoline barrier property is imparted.

It is a figure in which the fuel container accessory is mounted in the opening provided in the body of the fuel container. It is a figure by which the cut surface of the pinch-off part of a fuel container is coat | covered with the barrier material (C). It is a figure by which the cut surface of the layer which exists outside the layer which consists of barrier resin (A) among the cut surfaces of the opening part of the trunk | drum of a fuel container is coat | covered with the barrier material (C). FIG. 5 is a view in which a fuel container accessory part made of a barrier material (C) is attached to a recess provided by hollowing out the periphery of an opening part of a body part of a fuel container to cover a cut surface. It is a figure by which the cut surface of the opening part of the trunk | drum of a fuel container is coat | covered with the fuel container accessory which consists of barrier materials (C). It is a figure by which the groove | channel provided around the opening part of the trunk | drum of a fuel container is filled with the barrier material (C). It is a figure which shows the shape of the injection molded product created in Example 5. FIG. It is a figure in which the injection molded product created in Example 5 is attached to the opening of the container body of the fuel container body. It is a figure which shows the shape of the injection molded product created in Example 6. FIG. It is a figure by which the injection molded product produced in Example 6 is mounted | worn with the opening part of the container trunk | drum of a fuel container main body. It is a figure which shows the opening part of the container trunk | drum where the recessed part was formed concentrically with the opening part shown by Example 7. FIG. It is a figure with which the injection molded product created in Example 7 is mounted | worn with the opening part of the container trunk | drum of a fuel container main body. It is a figure by which the injection molded product created in the comparative example 3 is mounted | worn with the opening part of the container trunk | drum of a fuel container main body.

  The present invention relates to a fuel container having a layer made of a barrier resin (A) and an inner layer made of a thermoplastic resin (B) other than (A), and a coextrusion blow formed by covering a pinch-off portion with a barrier material (C). The present invention relates to a molded fuel container.

  The fuel container is preferably formed by coextrusion blow molding. In the method of manufacturing a plastic container by blow molding, a parison is formed by melt extrusion, the parison is sandwiched between a pair of blow molding dies, the parison is cut off and the opposite cut-off portion is fused, and then cut off. The parison is subjected to expansion in the mold to form a container. However, when the size of the container, such as a fuel tank for automobiles, is increased, the parison is clamped by a mold and crimped, but the mold is not cut and the part protruding from the container surface is of any height. It is often cut with a cutter. The fused and bonded portion is a pinch-off portion, and the cut surface cut by the mold or the surface cut by a cutter or the like is the cut surface of the pinch-off portion. The pinch-off part forms a tapered ridge protruding in the thickness direction of the container wall.

  In order to give the fuel container obtained by such coextrusion blow molding to the heat seal strength, mechanical strength and excellent gasoline barrier property of the pinch-off portion, a layer comprising the barrier resin (A) and heat other than (A) It is preferable to have an inner layer made of the plastic resin (B). Such a fuel container has an excellent gasoline barrier property due to the gasoline barrier property of the barrier resin (A). However, the barrier resin (A) has a permeation amount of fuel from the actually formed fuel container. It was larger than the calculated value calculated from the gasoline barrier property. As a result of detailed studies by the present inventors, it has been clarified for the first time that the permeation of gasoline from such a coextrusion blow molded fuel container is particularly remarkable at the pinch-off portion of the container.

  In contrast, in a fuel container having a layer made of a barrier resin (A) and an inner layer made of a thermoplastic resin (B) other than (A), a coextrusion blow formed by covering the pinch-off portion with a barrier material (C). It has been found that by using a molded fuel container, the permeation of fuel from the pinch-off portion of the fuel container, which has not been noticed so far, can be extremely effectively suppressed.

  In the present invention, the cut surface of the opening provided in the trunk of the container having a layer made of the barrier resin (A) and an outer layer made of the thermoplastic resin (B) other than (A) is used as the barrier material (C). It is related with the fuel container coat | covered with.

  Furthermore, the present invention provides a fuel container having a layer made of a barrier resin (A) and an outer layer made of a thermoplastic resin (B) other than (A), wherein the opening is provided in the container body. The present invention relates to a fuel container characterized in that a groove is provided on the outer surface around the inner surface of the, and the inner surface of the groove is covered with a barrier material (C). Further, the present invention provides a fuel container having a layer made of a barrier resin (A) and an outer layer made of a thermoplastic resin (B) other than (A), wherein the opening is provided in the container body. The present invention relates to a fuel container, characterized in that a groove is provided on the outer surface around and the groove is filled with a barrier material (C).

  As described above, the present inventors have so far proposed an accessory for a fuel container provided with a barrier property in order to suppress the fuel permeation amount from the fuel container. However, even when such a fuel container accessory is used, complete suppression of fuel permeation has not been achieved, and there is still room for improvement. As a result of further intensive studies by the present inventors on such a phenomenon, heat existing outside the barrier resin (A) at the cut surface of the opening of the trunk of the fuel container main body to which the fuel container accessory is mounted is shown. It became clear that fuel permeation occurred through the plastic resin (B) (see FIG. 1).

  Until now, the fuel container accessory attached to the opening provided in the container body was generally made of high-density polyethylene with poor gasoline barrier properties, so the cut surface of the opening provided in the fuel container body The permeation of fuel from was not excluded at all. However, as a result of the inventors' research, when it is necessary to achieve a very high level of fuel permeation suppression in the entire fuel container, such as when barrier properties are imparted to the fuel container accessory, the opening portion It has become clear that it is necessary to effectively suppress the permeation of fuel from the cut surface, and as a result of intensive studies, the present invention has been completed.

  That is, the cut surface of the opening provided in the body of the container having the layer made of the barrier resin (A) and the outer layer made of the thermoplastic resin (B) other than (A) is covered with the barrier material (C). By using the fuel container, it is possible to effectively suppress the permeation of fuel from the cut surface of the opening, and it is possible to provide a fuel container having an extremely excellent gasoline barrier property. Further, in a fuel container having a layer made of a barrier resin (A) and an outer layer made of a thermoplastic resin (B) other than (A) and having an opening in the container body, A fuel container, characterized in that a groove is provided on the outer surface and the inner surface of the groove is covered with a barrier material (C), a layer made of a barrier resin (A), and a thermoplastic other than (A) In a fuel container having an outer layer made of resin (B) and having an opening in the container body, a groove is provided on the outer surface around the opening, and the groove is filled with a barrier material (C) By using a fuel container characterized by being formed, a fuel container having an extremely excellent gasoline barrier property can be provided.

The barrier resin (A) used in the present invention is a resin having a barrier property against the fuel filled in the fuel container of the present invention. Since it is used for a multilayer container having the thermoplastic resin (B) other than (A) as an inner layer and / or outer layer, the barrier resin (A) is preferably a thermoplastic resin. The barrier resin (A) preferably has a gasoline permeation amount of 100 g · 20 μm / m ² · day (value measured at 40 ° C.-65% RH) or less. The upper limit of the gasoline permeation amount is more preferably 10 g · 20 μm / m ² · day or less, further preferably 1 g · 20 μm / m ² · day or less, and particularly preferably 0.5 g · 20 μm / m ^2. • Day or less, and optimally 0.1 g · 20 μm / m ² · day or less. Here, the gasoline used for measuring the gasoline permeation amount is Ref. It is a model gasoline called C that is mixed at a volume fraction of toluene / isooctane = 1/1.
The present invention has an excellent effect even when the fuel filled in the fuel container is a so-called oxygen-containing gasoline such as alcohol-containing gasoline containing alcohol such as methanol or MTBE (methyl tertiary butyl ether) -containing gasoline. Demonstrate.

  In addition, as the barrier resin (A) used in the present invention, it is also preferable to use at least one selected from the group consisting of polyvinyl alcohol resins, polyamides and aliphatic polyketones.

The polyvinyl alcohol resin in the present invention is a saponification of a vinyl ester polymer or a copolymer of vinyl ester and other monomers, particularly a copolymer of ethylene and vinyl ester using an alkali catalyst or the like. can get.
A typical vinyl ester is vinyl acetate, but other fatty acid vinyl esters (such as vinyl propionate and vinyl pivalate) can also be used.

Moreover, the saponification degree of the vinyl ester component of the polyvinyl alcohol resin of the present invention is preferably 90% or more, more preferably 95% or more, and further preferably 99% or more. If the degree of saponification is less than 90 mol%, the gasoline barrier property may be insufficient.
Here, when the polyvinyl alcohol-based resin is composed of a blend of two or more kinds of polyvinyl alcohol-based resins having different saponification degrees, the average value calculated from the blending weight ratio is defined as the saponification degree. The degree of saponification of such a polyvinyl alcohol resin can be determined by a nuclear magnetic resonance (NMR) method.

  As the polyvinyl alcohol-based resin of the present invention, a copolymer with EVOH (EVOH) is preferable from the viewpoint that it can be melt-molded, has a good gas barrier property under high humidity, and has an excellent gasoline barrier property. It is.

  The ethylene content of EVOH is preferably 5 to 60 mol%. If the ethylene content is less than 5 mol%, the gas barrier property under high humidity may be lowered and the melt moldability may be deteriorated. The lower limit of the ethylene content of EVOH is preferably 10 mol% or more, more preferably 15 mol% or more, and most preferably 20 mol% or more. The upper limit of the ethylene content is preferably 55 mol% or less, and more preferably 50 mol% or less. If the ethylene content exceeds 60 mol%, sufficient gas barrier properties may not be obtained. Further, the saponification degree of the vinyl ester component can be 85% or more, more preferably 90% or more, and still more preferably 99% or more. If the saponification degree of the vinyl ester component is less than 85%, the gasoline barrier property and thermal stability may be deteriorated. The ethylene content and the saponification degree of EVOH can be determined by a nuclear magnetic resonance (NMR) method.

Here, when EVOH is composed of a blend of two or more types of EVOH having different ethylene contents or saponification degrees, the average value calculated from the blending weight ratio is taken as the ethylene content or saponification degree.
However, when blending two types of EVOH, it is preferable that the difference in ethylene content between the two is 15 mol% or less and the difference in the degree of saponification is 10% or less. If these conditions are not met, the gasoline barrier property of the resin composition layer may be impaired. From the viewpoint of obtaining good gasoline barrier properties, the difference in ethylene content is more preferably 10 mol% or less, and even more preferably 5 mol% or less. Similarly, from the viewpoint of obtaining good gasoline barrier properties, the difference in the degree of saponification is more preferably 7% or less, and further preferably 5% or less.

  In addition, a small amount of other monomers can be copolymerized with the polyvinyl alcohol-based resin, particularly EVOH, as long as the object of the present invention is not impaired. Examples of monomers that can be copolymerized include α-olefins such as propylene, 1-butene, isobutene, 4-methyl-1-pentene, 1-hexene, 1-octene; itaconic acid, methacrylic acid, acrylic acid, anhydrous Unsaturated carboxylic acids such as maleic acid, salts thereof, partial or complete esters thereof, nitriles thereof, amides thereof, anhydrides thereof; vinylsilane compounds such as vinyltrimethoxysilane; unsaturated sulfonic acids or salts thereof; alkylthiols; And vinyl pyrrolidones.

  In particular, when EVOH contains a vinylsilane compound of 0.0002 to 0.2 mol% as a copolymerization component, the consistency of the melt viscosity with the base resin during coextrusion molding or coinjection molding is improved, A homogeneous molded body can be produced. Here, examples of the vinylsilane compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β-methoxy-ethoxy) silane, and γ-methacryloxypropylmethoxysilane. Of these, vinyltrimethoxysilane and vinyltriethoxysilane are preferably used.

Furthermore, when EVOH contains a boron compound, it is effective in that the melt viscosity, thermal stability and long run property of EVOH are improved, and a homogeneous co-extrusion or co-injection molded product can be obtained stably. Examples of the boron compound include boric acids, boric acid esters, borates, borohydrides, and the like. Specifically, examples of boric acids include boric acid, orthoboric acid, metaboric acid, and tetraboric acid. Examples of boric acid esters include triethyl borate and trimethyl borate. These include alkali metal salts, alkaline earth metal salts, and borax of various boric acids. Of these compounds, boric acid is preferred.
The content of the boron compound is 20 to 2000 ppm, preferably 50 to 1000 ppm in terms of boron element. By being in this range, EVOH in which torque fluctuation during heating and melting is suppressed can be obtained. If it is less than 20 ppm, such an effect is small, and if it exceeds 2000 ppm, gelation tends to occur and moldability may be deteriorated.

In addition, it is preferable to contain an alkali metal salt in an amount of 5 to 5000 ppm in terms of an alkali metal element in the EVOH of the present invention because it is effective for improving interlayer adhesion and compatibility.
A more preferable content of the alkali metal salt is 20 to 1000 ppm, further 30 to 750 ppm in terms of alkali metal element. Examples of the alkali metal include lithium, sodium, and potassium, and examples of the alkali metal salt include an aliphatic carboxylate, aromatic carboxylate, phosphate, and metal complex of a monovalent metal. Examples thereof include sodium acetate, potassium acetate, sodium phosphate, lithium phosphate, sodium stearate, potassium stearate, sodium salt of ethylenediaminetetraacetic acid, and the like. Of these, sodium acetate, potassium acetate, and sodium phosphate are preferred.

  Moreover, it is also preferable to contain 10-500 ppm of phosphoric acid compounds in terms of phosphate radicals with respect to the EVOH of the present invention, and by adding the phosphoric acid compound in an appropriate range, coloring of molded products and generation of gels and blisters are achieved. It is possible to suppress. The above improvement effect due to the addition of the phosphoric acid compound is particularly remarkable at the time of long-run molding using a resin composition pellet made of EVOH and at the time of recovery of the molded product. Examples of the phosphoric acid compound include, but are not limited to, various acids such as phosphoric acid and phosphorous acid and salts thereof. The phosphate may be contained in any form of primary phosphate, secondary phosphate, and tertiary phosphate, and the cation species is not particularly limited, but alkali metal salts An alkaline earth metal salt is preferred. Among these, it is preferable to add the phosphoric acid compound in the form of sodium dihydrogen phosphate, potassium dihydrogen phosphate, disodium hydrogen phosphate, or dipotassium hydrogen phosphate.

  The content of the phosphoric acid compound is preferably at least 50 ppm, more preferably at least 70 ppm, and the upper limit is preferably at most 300 ppm, more preferably at most 200 ppm, in terms of phosphate radical. By containing the phosphoric acid compound in such a range, a resin composition pellet made of EVOH with less coloring and less gelation can be obtained. When the content of the phosphoric acid compound is less than 10 ppm, there is a possibility that coloring during melt molding becomes severe. In particular, since the tendency is remarkable when the heat history is accumulated, a molded product obtained by molding the resin composition pellet may be poor in recoverability. Moreover, when content of a phosphoric acid compound exceeds 500 ppm, there exists a possibility that the gel of a molded product may occur easily.

  Moreover, the suitable melt flow rate (MFR) (190 degreeC, 2160-g load, based on JISK7210) of EVOH used for this invention is 0.01-100 g / 10min, More preferably, 0.05-50 g / 10 Min, more preferably 0.1 to 10 g / 10 min.

  In addition, a heat stabilizer, an ultraviolet absorber, an antioxidant, a colorant, a filler, and other resins (polyamide, polyolefin, etc.) can be blended with the EVOH resin without departing from the object of the present invention.

  The polyamide used as the barrier resin (A) of the present invention is a polymer having an amide bond, such as polycaproamide (nylon-6), polyundecanamide (nylon-11), polylauryllactam (nylon). -12), homopolymers such as polyhexamethylene adipamide (nylon-6,6), polyhexamethylene sebacamide (nylon-6,12), caprolactam / lauryllactam copolymer (nylon-6 / 12) ), Caprolactam / aminoundecanoic acid polymer (nylon-6 / 11), caprolactam / ω-aminononanoic acid polymer (nylon-6,9), caprolactam / hexamethylenediammonium adipate copolymer (nylon-6 / 6, 6) Caprolactam / hexamethylene diammonium adipate / f Samethylene diammonium sebacate copolymer (nylon-6 / 6,6 / 6,12), a polymer of adipic acid and metaxylylenediamine, or a polymer of hexamethylenediamine and m, p-phthalic acid And aromatic nylon. These polyamides can be used alone or in combination of two or more.

  Among these polyamides, nylon-6 is preferred from the viewpoint of gasoline barrier properties.

  The aliphatic polyketone used as the barrier resin (A) of the present invention is a carbon monoxide-ethylene copolymer, and the carbon monoxide-ethylene copolymer is a copolymer of carbon monoxide and ethylene. Or obtained by copolymerizing an unsaturated compound other than ethylene with carbon monoxide and ethylene as main components. Here, examples of unsaturated compounds other than ethylene include α-olefins having 3 or more carbon atoms, styrene, dienes, vinyl esters, and aliphatic unsaturated carboxylic acid esters. Examples of the copolymer include a random copolymer and an alternating copolymer, but an alternating copolymer with high crystallinity is preferable in terms of barrier properties.

  Among the alternating copolymers, copolymerization with a third component other than carbon monoxide or ethylene is preferable from the viewpoint of melt stability because the melting point is lowered. Among the monomers to be copolymerized, α-olefin is preferable and includes propylene, butene-1, isobutene, pentene-1, 4-methylpentene-1, hexene-1, octene-1, and dodecene-1. Among them, α-olefins having 3 to 8 carbon atoms are preferable, and propylene is particularly preferable. The copolymerization amount of these α-olefins is preferably 0.5 to 7% by weight based on the polyketone from the viewpoint of ensuring appropriate crystallinity and melt stability.

  The diene to be copolymerized preferably has 4 to 12 carbon atoms, and examples thereof include butadiene, isoprene, 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene and the like. Examples of the vinyl ester include vinyl acetate, vinyl propionate, and vinyl pivalate. Aliphatic unsaturated carboxylic acids, salts and esters thereof include acrylic acid, methacrylic acid, maleic anhydride, maleic acid, itaconic acid, acrylic ester, methacrylic ester, maleic monoester, maleic diester, fumaric acid Monoesters, fumaric acid diesters, itaconic acid monoesters, itaconic acid diesters (these esters include methyl esters, alkyl esters such as ethyl esters), acrylates, maleates, itaconates (as these salts) Monovalent or divalent metal salts). These comonomer may be used alone or in combination of two or more.

  Examples of the production method of the polyketone include known methods, for example, methods described in Patent Documents 7 to 18, but are not particularly limited thereto.

  The preferred melt flow rate (MFR) of the polyketone used in the present invention is 0.01 to 50 g / 10 min (under 230 ° C. and 2160 g load), optimally 0.1 to 10 g / 10 min. When the MFR is in the above range, the fluidity of the resin is excellent, and the molding processability is also excellent.

  Among these resins, as the barrier resin (A) used in the present invention, polyvinyl alcohol resins and polyamides are preferable from the viewpoint of gasoline barrier properties, and EVOH is particularly preferable.

  The thermoplastic resin (B) used as the inner layer and / or outer layer in the present invention includes linear low density polyethylene, low density polyethylene, medium density polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer, ethylene- Propylene copolymer, polypropylene, propylene-α-olefin copolymer (α-olefin having 4 to 20 carbon atoms), olefin alone such as polybutene, polypentene or a copolymer thereof, polystyrene, polyvinyl chloride, polyvinylidene chloride , Acrylic resin, vinyl ester resin, polyurethane elastomer, polycarbonate, chlorinated polyethylene, chlorinated polypropylene, and the like. Among these, polypropylene, polyethylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, and polystyrene are preferably used.

Among them, it is preferable to use polyethylene having a density of 0.93 or more as the thermoplastic resin (B) used in the present invention. Polyethylene having a density of 0.93 or more can usually be used by appropriately selecting from commercially available products. Among these, from the viewpoint of rigidity, impact resistance, moldability, drawdown resistance, gasoline resistance, etc., such density more preferably a density of 0.93 or more polyethylene is 0.95~0.98g / cm ^3, more preferably from 0.96~0.98g / cm ^3. The melt flow rate (MFR) of polyethylene having a density of 0.93 or more is preferably from 0.01 to 0.5 g / 10 min (under 190 ° C. and 2160 g load), more preferably from 0.01 to 0.00. 1 g / 10 min (under 190 ° C. and 2160 g load).

  The fuel container of the present invention is preferably formed by laminating an inner layer and / or an outer layer made of a thermoplastic resin (B) with an adhesive resin layer on a layer made of a barrier resin (A). It is. As such an adhesive resin layer, a carboxylic acid-modified polyolefin is preferably used.

  The carboxylic acid-modified polyolefin used in the present invention refers to a copolymer comprising an olefin, particularly an α-olefin, and an unsaturated carboxylic acid or an anhydride thereof. In the polyolefin and polyolefin having a carboxyl group in the molecule. Those in which all or part of the contained carboxyl groups are present in the form of metal salts are also included. Examples of the polyolefin used as the base of the carboxylic acid-modified polyolefin include polyethylene (for example, high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and very low density polyethylene (VLDPE)). Various polyolefins such as polypropylene, copolymerized polypropylene, ethylene-vinyl acetate copolymer, and ethylene- (meth) acrylic acid ester copolymer can be mentioned. Of these, linear low-density polyethylene, ethylene-vinyl acetate copolymer (Vinyl acetate content of 5 to 55% by weight), ethylene-acrylic acid ethyl ester copolymer (acrylic acid ethyl ester content of 8 to 35% by weight) is preferred, linear low density polyethylene and ethylene- A vinyl acetate copolymer is particularly preferred.

  Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, ethacrylic acid, maleic acid, monomethyl maleate, monoethyl maleate, and itaconic acid. Acrylic acid or methacrylic acid is particularly preferable. Content of unsaturated carboxylic acid becomes like this. Preferably it is 0.5-20 mol%, More preferably, it is 2-15 mol%, More preferably, it is 3-12 mol%. Examples of the unsaturated carboxylic acid anhydride include itaconic anhydride and maleic anhydride, and maleic anhydride is particularly preferable. As content of unsaturated carboxylic acid anhydride, Preferably it is 0.0001-5 mol%, More preferably, it is 0.0005-3 mol%, More preferably, it is 0.001-1 mol%. Other monomers that may be contained in the copolymer include vinyl esters such as vinyl acetate and vinyl propionate, methyl acrylate, ethyl acrylate, isopropyl acrylate, isobutyl acrylate, and acrylic acid n. Examples thereof include unsaturated carboxylic acid esters such as butyl, 2-ethylhexyl acrylate, methyl methacrylate, isobutyl methacrylate and diethyl maleate, and carbon monoxide.

  Examples of the metal ion in the metal salt of the carboxylic acid-modified polyolefin include alkali metals such as lithium, sodium and potassium, alkaline earth metals such as magnesium and calcium, and transition metals such as zinc. The degree of neutralization of the metal salt of the carboxylic acid-modified polyolefin is desirably 100% or less, particularly 90% or less, and more preferably 70% or less. The lower limit of the degree of neutralization is usually preferably 5% or more, particularly 10% or more, and more preferably 30% or more.

  The melt flow rate (MFR) (under 190 ° C. and 2160 g load) of the carboxylic acid-modified polyolefin used in the present invention is preferably 0.01 to 50 g / 10 minutes, more preferably 0.05 to 30 g / 10 minutes, Preferably it is 0.1-10 g / 10min. These carboxylic acid-modified polyolefins can be used alone or in combination of two or more.

  The barrier material (C) used in the present invention refers to a material that exhibits a barrier property to the fuel filled in the fuel container in the same manner as the barrier resin (A). Preferably, the gasoline permeation amount (measured at 40 ° C.-65% RH) of the barrier material (C) used in the present invention is measured by the gasoline permeation amount (40 ° C.-65% RH) of the thermoplastic resin (B). Value) is 0.1 times or less. The upper limit of the gasoline permeation amount of the barrier material (C) is more preferably 0.05 times or less, and further preferably 0.01 times or less of the gasoline permeation amount of the thermoplastic resin (B).

  When the gasoline permeation amount of the barrier material (C) exceeds 0.1 times the gasoline permeation amount of the thermoplastic resin (B), there is a possibility that the ability as a barrier material may be insufficient, and from the pinch-off portion and the body opening portion. There is a risk that the effect of reducing the amount of permeated fuel becomes unsatisfactory.

Moreover, it is also preferable that the gasoline permeation amount of the barrier material (C) used in the present invention is 400 g · 20 μ / m ² · day (value measured at 40 ° C.-65% RH) or less. If the gasoline permeation amount exceeds 400g · 20μ / m ² · day (measured at 40 ° C-65% RH), there is a risk that the ability as a barrier material will be insufficient, and the pinch-off part and trunk opening part There is a possibility that the effect of reducing the amount of permeated fuel from the fuel becomes unsatisfactory. The gasoline permeation amount of the barrier material (C) is more preferably 100 g · 20 μ / m ² · day (measured at 40 ° C.-65% RH) or less, and 50 g · 20 μ / m ² · day (40 ° C.− More preferably, it is 10 g · 20 μ / m ² · day (value measured at 40 ° C.-65% RH) or less, preferably 1 g · 20 μ / m ^2. -It is optimal that it is not more than day (value measured at 40 ° C-65% RH).

  In addition, as the barrier material (C) used in the present invention, at least one selected from the group consisting of metal foil, epoxy resin, polyvinylidene chloride resin, polyvinyl alcohol resin, polyamide resin, polyester resin, and fluororesin is used. It is also suitable. Among these, it is preferable to use a metal foil from the viewpoint of handling, and an embodiment in which the metal foil is laminated on a base material having adhesiveness with the fuel tank body, such as an aluminum tape, is particularly preferable. The metal foil is not particularly limited, and includes a metal vapor-deposited film and a metal oxide vapor-deposited film. Aluminum foil is preferable from the viewpoint of availability and handling.

  Further, when the barrier material (C) is a thermoplastic resin, an appropriate amount of other thermoplastic resin may be blended in order to improve mechanical strength, moldability, etc., as long as the object of the present invention is not impaired. Is optional. Examples of thermoplastic resins include various polyolefins (polyethylene, polypropylene, poly 1-butene, poly 4-methyl-1-pentene, ethylene-propylene copolymers, copolymers of ethylene and α-olefins having 4 or more carbon atoms, polyolefins. Copolymer of ethylene and maleic anhydride, ethylene-vinyl ester copolymer, ethylene-acrylic ester copolymer, or modified polyolefin obtained by graft-modifying these with unsaturated carboxylic acid or derivatives thereof), polystyrene, polyacrylonitrile Etc. are used.

The fuel container of the present invention is a fuel container having a layer made of a barrier resin (A) and an inner layer made of a thermoplastic resin (B) other than (A), and the pinch-off portion is covered with a barrier material (C). It is a coextrusion blow molded fuel container. Further, the fuel container of the present invention has a cut surface of an opening provided in a body portion of a container having a layer made of a barrier resin (A) and an outer layer made of a thermoplastic resin (B) other than (A) as a barrier material. A fuel container coated with (C). The method for covering the cut surface of the pinch-off portion of the fuel container and / or the cut surface of the opening provided in the body portion of the fuel container main body with the barrier material (C) is not particularly limited.
Method of solidifying or drying after applying barrier material (C) having adhesiveness to fuel container main body to cut surface; applying adhesive having adhesiveness to both fuel container main body and barrier material (C) to cut surface Thereafter, a method of covering the cut surface with the barrier material (C); a method of covering the cut surface with a laminate (for example, aluminum tape) made of the barrier material (C) and an adhesive, and a barrier material (C). Examples include a method in which a molded product is bonded to a cut surface by thermal fusion, or is bonded through an adhesive to cover the cut surface. In addition, although the molded article which consists of barrier materials (C) is not specifically limited, a film or a sheet | seat or a fuel container accessory etc. are illustrated as a suitable thing.

  Among these coating methods, from the viewpoint of ease of work, the barrier material (C) is previously coated on a base material having adhesiveness to the fuel tank body, and a cut surface is obtained using such a laminate (for example, aluminum tape). A method of covering the cut surface by joining the cut surface of the barrier material (C) to the cut surface by thermal fusion or bonding via an adhesive is preferable.

  Further, when the cut surface is covered with a molded article made of the barrier material (C), particularly preferably with an accessory for a fuel container, the outer surface around the opening is cut out and the molded article is heated in the obtained recess. A mode of fusing is also suitable (see FIG. 4). As the molded product made of the barrier material (C), a single-layer molded product made of the barrier material (C) may be used, or a multilayer molded product having at least one layer made of the barrier material (C) may be used. . In the case where the cut surface is coated in such an embodiment, it is particularly preferable from the viewpoint of workability at the time of performing heat fusion as compared with the method of covering the cut surface according to the embodiment as shown in FIG.

  Although the depth of the said recessed part is arbitrary, it is preferable that it is 0.1-0.8 times of the container trunk | drum average whole layer thickness (T2). The lower limit of the depth of the concave portion is more preferably 0.2 times or more, and further preferably 0.3 times or more of the container body portion average total layer thickness (T2). Further, the upper limit of the depth of the recess is preferably 0.75 times or less, more preferably 0.7 times or less of the container body average total layer thickness (T2). When the depth of the recess is less than 0.1 times the container body average total layer thickness (T2), the gasoline barrier property improving effect may be unsatisfactory. If the depth of the recess exceeds 0.8 times the container body average total layer thickness (T2), the mechanical strength of the fuel container body around the recess may be unsatisfactory.

  Moreover, it is provided with the said recessed part that the depth of a recessed part is 0.2 times or more and less than 1 time of the total thickness (T1) of the layer which exists outside the layer which consists of barrier resin (A). Moreover, it is preferable from the viewpoint of mechanical strength around the opening of the container body. The lower limit of the depth of the recess is more preferably 0.3 times or more of (T1), and further preferably 0.5 times or more. When the depth of the recess is less than 0.2 times (T1), the effect of improving the gasoline barrier property may be insufficient. From the viewpoint of obtaining heat-fusibility with a molded article made of the barrier material (C), the upper limit of the depth of the recess is more preferably 0.999 times or less of (T1), and 0.995 times or less. More preferably, it is preferably 0.99 times or less, particularly when the heat-fusibility is important.

  When the gasoline barrier property is particularly important, the depth of the recess is preferably (T1) or more. In this embodiment, since the fuel permeation path from the layer existing outside the barrier resin (A) can be closed with the barrier material (C) without gaps, an extremely excellent gasoline barrier property can be obtained. However, since the barrier resin (A) is exposed when the depth of the recess is equal to (T1), the molded product made of the barrier material (C) is heat-sealed to cover the cut surface of the recess. However, there is a possibility that the heat-fusibility is insufficient. Moreover, when the depth of a recessed part exceeds (T1), there exists a possibility that the mechanical strength of this recessed part periphery may become inadequate.

  When the barrier material (C) is used to cover the pinch-off portion of the fuel container of the present invention, the entire pinch-off portion may be covered or a part thereof may be covered, but the effect of the present invention is efficiently In view of the above, it is preferable to cover the entire cut surface of the pinch-off portion. It is preferable from the viewpoint of obtaining sufficient gasoline barrier properties that at least the cut surface of the layer existing between the opposing barrier resin (A) layers is coated with the barrier material (C) (see FIG. 2). By completely covering at least such a portion of the entire pinch-off portion, fuel permeation from the pinch-off portion can be effectively suppressed.

  Similarly, when the cut surface of the opening provided in the body portion of the fuel container of the present invention is covered with the barrier material (C), the entire cut surface may be covered or a part thereof may be covered. However, from the viewpoint of obtaining sufficient gasoline barrier properties, at least the cut surface of the layer outside the layer made of the barrier resin (A) is covered with the barrier material (C). It is preferable to be formed (see FIG. 3). By completely covering at least such a portion of the entire cut surface, fuel permeation from the opening provided in the body portion of the fuel container can be effectively suppressed.

The fuel container of the present invention is a fuel container having a layer made of a barrier resin (A) and an outer layer made of a thermoplastic resin (B) other than (A), and an opening is provided in the container body. The fuel container is characterized in that a groove is provided on the outer surface around the opening, and the inner surface of the groove is covered with a barrier material (C). The fuel container of the present invention is a fuel container having a layer made of a barrier resin (A) and an outer layer made of a thermoplastic resin (B) other than (A), and an opening is provided in the container body. The fuel container is characterized in that a groove is provided on the outer surface around the opening, and the groove is filled with a barrier material (C). The periphery of the opening of the fuel container having the layer made of the barrier resin (A) and the outer layer made of the thermoplastic resin (B) other than (A) and having the opening provided in the container body The method of covering the inner surface of the groove provided on the outer surface of the substrate with the barrier material (C) and the method of filling the groove with the barrier material (C) are not particularly limited.
As a method for coating the inner surface of the groove with the barrier material (C), an adhesive having adhesiveness is applied to both the fuel container main body and the barrier material (C) on the cut surface, and then the groove material is coated with the barrier material (C). A method of coating the inner surface; a method of coating the inner surface of the groove using a laminate (for example, aluminum tape) made of a barrier material (C) and an adhesive; a barrier material (C) having adhesiveness with the fuel container body And a method of solidifying or drying after coating on the inner surface of the substrate.

  As a method of filling the groove with the barrier material (C), a method of filling the groove with the barrier material (C) having adhesiveness with the fuel container main body and solidifying or drying is preferable. In this case, even if the barrier material (C) is bonded by pseudo-adhesion, the gasoline barrier property that is the effect of the present invention can be exhibited, but it is preferable that the fuel tank body is firmly bonded from the viewpoint of mechanical strength and the like. . When using the method of filling the groove with the barrier material (C) having adhesiveness with the fuel container body and solidifying or drying, attach the fuel container accessory made of the barrier material (C ′) to the opening. Is particularly preferable from the viewpoint of obtaining sufficient gasoline barrier properties (see FIG. 6). As the fuel container accessory made of the barrier material (C ′), a single-layer molded product made of the barrier material (C ′) may be used, or multilayer molding having at least one layer made of the barrier material (C ′). You may use goods.

  In addition, as a method of filling the groove with the barrier material (C), a method of heat-sealing a molded article made of the barrier material (C), particularly preferably a fuel container accessory part, to the groove is also suitable.

  Embodiment in which a groove as described above is provided and the inner surface of the groove is covered, or when the groove is filled with the barrier material (C), the cut surface of the opening is directly covered with the barrier material (C). Compared to the above, it is preferable in that direct contact between the barrier material (C) and the fuel can be avoided. Since the barrier material (C) exhibits a barrier property against the fuel in the container, deterioration due to direct contact is unlikely to occur. However, the presence of the barrier material (C) in the fuel flow path surface prevents the barrier material (C) from being used for a long period of time. There is a risk of peeling easily due to physical force.

  Further, in the method of filling the groove by thermally fusing the fuel accessory part made of the barrier material (C), the fuel accessory part made of the barrier material (C) is thermally fused to the cut surface of the opening. This is more preferable than the embodiment (see FIG. 5) from the viewpoint of facilitating heat fusion.

  In addition, it is preferable that the groove provided on the outer surface around the opening surrounds the opening without interruption from the viewpoint of blocking the fuel permeation path and effectively improving the gasoline barrier property. When the groove surrounds the opening without interruption, the area of the portion surrounded by the groove is preferably 1.1 to 50 times the area of the opening. From the viewpoint of workability when creating the groove, the upper limit of the area of the portion surrounded by the groove is more preferably 30 times or less, and even more preferably 10 times or less the area of the opening. It is particularly preferable that the ratio is not more than twice. Furthermore, it is preferable that the shape of the groove is circular because it is easy to create a groove surrounding the opening without interruption.

  The depth of the groove is preferably 0.1 to 0.8 times the container trunk average total layer thickness (T2). The lower limit of the depth of the groove is preferably 0.2 times or more, and more preferably 0.3 times or more the container trunk average total layer thickness (T2). Further, the upper limit of the depth of the groove is preferably 0.75 times or less, more preferably 0.7 times or less of the container body average total layer thickness (T2). If the depth of the groove is less than 0.1 times the container body average total layer thickness (T2), the gasoline barrier property improving effect may be unsatisfactory. Further, when the depth of the groove exceeds 0.8 times the container body average total layer thickness (T2), the mechanical strength of the fuel container body around the groove may be unsatisfactory.

  In addition, the groove is provided so that the depth of the groove is 0.2 times or more and less than 1 time the total thickness (T1) of the layers existing outside the layer made of the barrier resin (A). Moreover, it is preferable from the viewpoint of mechanical strength around the opening of the container body. The lower limit of the depth of the groove is more preferably 0.3 times or more of (T1), and further preferably 0.5 times or more. If the depth of the groove is less than 0.2 times (T1), the effect of improving the gasoline barrier property may be insufficient. From the viewpoint of obtaining heat-fusibility with the molded article made of the barrier material (C), the upper limit of the groove depth is more preferably 0.999 times or less of (T1), and 0.995 times or less. More preferably, it is preferably 0.99 times or less, particularly when the heat-fusibility is important.

  When the gasoline barrier property is particularly important, the depth of the groove is preferably (T1) or more. In this embodiment, since the fuel permeation path from the layer existing outside the barrier resin (A) can be closed with the barrier material (C) without gaps, an extremely excellent gasoline barrier property can be obtained. However, when the depth of the groove is equal to (T1), the barrier resin (A) is exposed. Therefore, when the molding made of the barrier material (C) is heat-sealed to cover the cut surface of the concave portion However, there is a possibility that the heat-fusibility is insufficient. If the depth of the groove exceeds (T1), the mechanical strength around the opening may be insufficient. The barrier resin (A) layer may be used in two or more layers. In such a configuration, the barrier resin (A) layer located on the outermost layer side in the two or more barrier resin (A) layers is used. A) The total thickness of the layers existing outside the layer is regarded as (T1).

  The layer structure of the fuel container main body of the present invention is not particularly limited, but in consideration of moldability and cost, the barrier resin (A) is a thermoplastic resin other than A and (A) (B ) Is B and the adhesive resin is Tie, (inner) B / A / B (outer), (inner) B / Tie / A (outer), (inner) B / Tie / A / Tie / B ( Outer), (Inner) B / Tie / A / Tie / A / Tie / B (outer), and the like are typical examples. When the thermoplastic resin (B) and adhesive resin other than the barrier resin (A) and (A) are used in a plurality of layers, the same resin may be used, or different resins may be used.

  In particular, when the fuel container of the present invention is used as a fuel tank, (inner) B / Tie / A / Tie / B from the viewpoint of rigidity, impact resistance, moldability, drawdown resistance, gasoline resistance, and the like. It is particularly preferable to employ the (outer) layer structure.

  The thickness of each layer of the fuel container of the present invention is not particularly limited. However, when considering the gasoline barrier property, mechanical strength, cost merit, etc. of the fuel container, the thickness of the barrier resin (A) layer is 0. It is preferable that it is 1 to 20%. The lower limit of the thickness of the barrier resin (A) layer is more preferably 0.5% or more, and further preferably 1% or more with respect to the total layer thickness. Moreover, the upper limit of the thickness of the barrier resin (A) layer is more preferably 15% or less, and even more preferably 10% or less with respect to the total thickness. If the thickness of the barrier resin (A) layer is less than 0.1% of the total thickness, the gasoline barrier property of the container may be insufficient, and if it exceeds 20%, the cost will be high. In addition, the mechanical strength may be unsatisfactory. When there are a plurality of barrier resin (A) layers, the total thickness of each barrier resin (A) layer is defined as the thickness of the barrier resin (A) layer.

  From the viewpoint of suppressing the fuel permeation amount from the cut surface of the opening provided in the body portion of the container, the total thickness of the layers existing outside the layer made of the barrier resin (A) in the container body portion ( The ratio (T1 / T2) of T1) to the total layer thickness (T2) is preferably 45/100 or less. The fuel in the container passes through a layer outside the layer made of the barrier resin (A) and permeates to the outside (see FIG. 1), and therefore exists outside the layer made of the barrier resin (A). By reducing the total thickness (T1) of the layers, it is possible to relatively reduce the amount of fuel permeated from the fuel container.

  In the container body, the upper limit of the ratio (T1 / T2) of the total thickness (T1) and the total thickness (T2) of the layers existing outside the layer made of the barrier resin (A) is 45/100 or less. Preferably, it is 40/100 or less, more preferably 35/100 or less, and particularly preferably 30/100 or less.

The lower limit of the ratio (T1 / T2) is not particularly limited, and the barrier resin (A) may be the outermost layer. However, the fuel container having the barrier resin (A) as the outermost layer may not be preferable from the viewpoints of mechanical strength and thermal fusion with the fuel container accessory. For this reason, the fuel container of the present invention preferably has an intermediate layer made of a barrier resin (A) and an inner / outer layer made of a thermoplastic resin (B) other than (A), and the ratio (T1 / The lower limit of T2) is preferably 1/100 or more, and more preferably 5/100 or more.
The barrier resin (A) layer may be used in two or more layers. In such a configuration, the barrier resin (A) layer located on the outermost layer side in the two or more barrier resin (A) layers is used. A) The total thickness of the layers existing outside the layer is regarded as (T1).

  From the viewpoint of suppressing fuel permeation, it is also preferable to blend the barrier resin (A) with the thermoplastic resin (B) on the outer layer side. By adopting such a configuration, it is possible to obtain a fuel container that has a certain degree of mechanical strength and heat fusion between the fuel container accessory and that further improves gasoline barrier properties. The thermoplastic resin (B) on the outer layer side may be a single layer or a multilayer structure, but in the case of a multilayer structure, the blend layer obtained by blending the barrier resin (A) is the top. The outer layer is preferable from the viewpoint of gasoline barrier properties.

  When molding a fuel container, burrs are usually inevitable. By remelting such burrs and rejected products at the time of molding and using them as a recovery layer, it is possible to reduce the loss of the resin used at the time of producing the container and improve the recyclability.

  The recovery layer is generally formed by remelting a multilayer structure composed of a thermoplastic resin and a barrier layer (and an adhesive resin layer in some embodiments), and can be used in place of the thermoplastic resin (B) layer. However, it is preferable to use it laminated with a thermoplastic resin (B) layer. In general, the recovery layer often has lower mechanical strength than the layer made of a single thermoplastic resin. When the container receives an impact from the outside, the stress against the impact acts on the inner layer side of the container, causing the container to be distorted and possibly causing breakage. It is suitable to arrange on the outer layer side. However, when a large amount of resin needs to be recycled, such as when burrs are frequently generated, it is preferable to arrange recovery layers on both sides of the barrier layer.

  Moreover, it is preferable that the fuel container of the present invention has a fuel container accessory attached to an opening provided in the body part. Specific examples of the fuel container accessory in the present invention include, but are not limited to, a fuel tank connector, a fuel tank cap, and a fuel tank valve.

  In order to fully demonstrate the effects of the present invention, it is preferable that the fuel container accessory has a barrier property, and is made of a metal fuel container accessory or a resin composition having a barrier property. It is preferable to use fuel container accessories (Japanese Patent Application Nos. 11-172151 and 11-172152).

  In a particularly preferred embodiment of the present invention, in a fuel container having a layer made of a barrier resin (A) and an inner and outer layer made of a thermoplastic resin (B) other than (A), the pinch-off portion is made of a barrier material (C). A fuel container formed by coating a cut surface of an opening provided in a body portion of a coextrusion blow-molded fuel container with a barrier material (C), and the fuel container having a barrier property. It is further preferable that the accessory part is attached.

  Since the fuel container obtained as described above is extremely excellent in fuel barrier properties, fuel pipes or tanks that require barrier properties for fuel, particularly oxygenated gasoline, such as automobile gasoline tanks, petroleum stoves, etc. It is useful as a fuel tank.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, it is not limited at all by this. In each example, the fuel permeation amount of the resin and the fuel permeation amount of the tank were measured as follows.

<Measurement of fuel permeation amount of resin used>
Measurement of fuel permeation amount of barrier resin (A) (1) BA-055 manufactured by Paxon (density 0.970, MFR at 190 ° C.−2160 g = 0.03 g / 10 min) as high density polyethylene (HDPE), Using ADMER GT-6A (MFR = 0.94 g / 10 min at 190 ° C.-2160 g) as the adhesive resin (Tie), high-density polyethylene, barrier resin (A), and adhesive resin were separately extruded. Co-extrusion with a total layer thickness of 120 μm having a constitution of high density polyethylene / adhesive resin / barrier resin (A) / adhesive resin / high density polyethylene (film thickness 50 μm / 5 μm / 10 μm / 5 μm / 50 μm) Sheets were obtained with a molding device. Extrusion molding was carried out with a high-density polyethylene having a diameter of 65 mm and an extruder equipped with a uniaxial screw of L / D = 24 at a temperature of 170 to 210 ° C., and the adhesive resin having a uniaxial screw of 40 mm in diameter and L / D = 22 mm. The extruder is set to a temperature of 160 to 210 ° C., the barrier resin (A) has a diameter of 40 mm, and the extruder provided with a single screw of L / D = 22 is set to a temperature of 170 to 210 ° C. ) Was operated at 210 ° C. to obtain a coextruded sheet (a1).
(2) One side of the coextruded sheet (a1) was coated with an aluminum tape (manufactured by FP Corporation, trade name: aluminum seal: gasoline barrier property = 0 g · 20 μm / m ² · day).
(3) The coextruded sheet (a1) and the coextruded sheet (b1) covered with aluminum tape were each cut into a size of 210 mm × 300 mm.
(4) Each cut sheet was bent at the center, and two sides were heat-sealed with a dial 6 to a seal width of 10 mm using a heat sealer T-230 manufactured by Fuji Impulse to produce a pouch.
(5) Each pouch has Ref. 200 ml of C (toluene / isooctane = 1/1) was filled from the unsealed side, and the sealed side was heat-sealed so as to have a seal width of 10 mm in the same manner as described above.
The fuel input pouch was left in an explosion-proof constant temperature and humidity chamber (40 ° C.-65% RH), and the weight of the pouch was measured every 7 days for 3 months. Such a test was performed on each of five coextruded pouches (a2) without aluminum foil and coextruded pouches (b2) coated with aluminum tape, and the weight change of the pouch before and after each standing time was read. The fuel permeation amount was calculated from the slope of the standing time and the weight change amount of the pouch.

  The fuel permeation amount of the coextrusion pouch (a2) without the aluminum tape represents the sum of the fuel permeation amounts from both the pouch surface and the heat seal part, and the fuel permeation amount of the coextrusion pouch (b2) covered with the aluminum tape is the heat. The fuel permeation amount from the seal portion is shown.

{Transmission amount from (a2)}-{Transmission amount from (b2)} is defined as the fuel transmission amount of the barrier resin (A), and the thickness is converted into the transmission amount per 20 μm of the barrier resin (A) layer. The fuel permeation amount (g · 20 μm / m ² · day) of the barrier resin (A) was determined.

・ Measurement of gasoline barrier property of thermoplastic resin (B) (1) Using Labo plast mill (diameter 20 mm, L / D = 22) manufactured by Toyo Seiki, using a coat hanger die of 300 mm width, thermoplastic resin (B ) Was melted at + 20 ° C. to prepare a 100 μm sheet, and the sheet was cut into a size of 210 mm × 300 mm.
(2) The cut sheet was bent at the center, and two sides were heat-sealed to a seal width of 10 mm with a dial 6 using a heat sealer T-230 manufactured by Fuji Impulse, and a pouch was produced.
(3) The ref. 200 ml of C (toluene / isooctane = 1/1) was filled from the unsealed side, and the sealed side was heat-sealed so as to have a seal width of 10 mm in the same manner as described above.
(4) The fuel input pouch was left in an explosion-proof thermostatic chamber (40 ° C.-65% RH), and the weight of the pouch was measured every 6 hours for 3 days. This test was carried out on five pouches, the weight change of the pouch before and after each standing time was read, the fuel permeation amount of the pouch was obtained from the slope of the standing time and the weight change amount of the pouch, and the heat was converted by thickness conversion. The fuel permeation amount (g · 20 μm / m ² · day) of the plastic resin (B) was calculated.

  In Example 1 in which the container body part did not have an opening and the cut surface of the pinch-off part was covered with aluminum tape, the fuel container showed excellent gasoline barrier properties. On the other hand, in Comparative Example 1 in which the cut surface of the pinch-off part was not covered at all, the fuel permeation amount was 0.04 (g / 3 months), which was doubled compared to Example 1.

  Further, the container body has an opening, and the ratio (T1 / T2) of the total thickness (T1) and the total thickness (T2) of the layers existing outside the layer made of the barrier resin (A) is In Example 4 which is 15/100, it was expected that the amount of fuel permeation from the entire tank would increase due to the arrangement of the barrier layer on the outer layer side, but in particular the opening provided in the barrel of the container Since the permeation of fuel from the cut surface could be effectively reduced, the gasoline tank as a whole had better gasoline barrier properties than Example 3 where (T1 / T2) was 49/100.

  In Example 2 in which both the cut surface of the pinch-off portion and the cut surface of the opening provided in the body portion of the container were coated, particularly excellent gasoline barrier properties were exhibited.

  On the other hand, in Comparative Example 2 in which neither the pinch-off part nor the cut surface of the opening provided in the body part of the container is covered with aluminum tape, compared with Example 2 in which both are covered with aluminum tape. More than three times the fuel permeation was observed.

Example 5
High-density polyethylene (HDPE: HZ8200B manufactured by Mitsui Chemicals) is used as the inner and outer layers, and adhesive resin (maleic anhydride modified LDPE, Admer GT5A manufactured by Mitsui Chemicals) is used. An EVOH multilayer tank having a surface area of 0.85 m ² was prepared. The layer structure of this tank was (outside) HDPE / adhesive resin / EVOH (A-1) / adhesive resin / HDPE (inside) = 2500/100/150/100/2500 (μm).

Ethylene content 32 mol%, saponification degree 99.5%, MFR = 190 g-2160 g MFR = 1.6 g / 10 min EVOH 30 parts by weight, ethylene content 89 mol%, saponification degree 97%, 190 ° C.-2160 g MFR = 5 g Barrier material which is a resin composition comprising 15 parts by weight of a saponified ethylene-vinyl acetate copolymer for 10 minutes per 10 minutes and 55 parts by weight of polyethylene having a density of 0.952 at 190 ° C. to 2160 g for MFR = 0.3 g / 10 minutes (C-1) was obtained by the following method. That is, EVOH, an ethylene-vinyl acetate copolymer saponified product having an ethylene content of 89 mol% and a saponification degree of 97 mol%, and a polyethylene having a density of 0.952 were placed in a twin screw type vent type extruder, and in the presence of nitrogen. Extrusion pelletization was performed at 220 ° C. to obtain pellets of the resin composition. The gasoline barrier property of the barrier material (C-1) was 45 g · 20 μm / m ² · day.

  The barrier material (C-1) was charged into an injection molding machine, and an injection molded product (see FIG. 7) having a diameter of 110 mm, a thickness of 4 mm, and a thickness of 6 mm for the end portion of the injection piece of 10 mm was created.

  Two circular openings having a diameter of 70 mm were provided in the body of the multilayer tank prepared above, and grooves having an outer diameter of 110 mm, an inner diameter of 100 mm, and a depth of 2 mm were provided concentrically with each of the openings. Both the groove portion and the injection molded product prepared above were melted with an iron plate at 250 ° C. for 40 seconds and then subjected to pressure bonding to obtain a multilayer tank in which two injection molded products were mounted by thermal fusion (FIG. 8). reference). Using the multilayer tank, the gasoline barrier property was evaluated by the following method.

<Gasoline barrier properties>
As a model gasoline, the Ref. C (toluene / isooctane = 1/1) was filled with 25 liters from the opening for blow-in, and the opening was filled with aluminum tape (manufactured by FP Corporation, trade name: aluminum seal: gasoline barrier property = 0 g · 20 μm / m ² · day). Thereafter, the tank was left in an explosion-proof thermostatic chamber (40 ° C.-65% RH), and the weight loss rate (W) after 3 months was measured (n = 5). This test was performed on five 35 L tanks, and the permeation amount of the tank was determined from the average value of the weight change of the tank before and after being left.

In addition, as a control, a multi-layer tank with two injection-molded products was prepared in the same manner as above except that the cut surface provided on the body of the multi-layer tank was covered with aluminum tape, and the tank was subjected to explosion-proof constant temperature. The sample was left in a constant humidity bath (40 ° C.-65% RH), and the weight loss rate (w) after 3 months was measured (n = 5). The fuel permeation amount from the thermoplastic resin (B) layer existing outside the barrier resin (A) layer is represented by the following formula (1).
Fuel permeation (g / 3 months) = W−w (1)
The fuel permeation amount in this example was 0.18 (g / 3 months).

Example 6
Injection was carried out in the same manner as in Example 5 except that the shape of the injection molded product made of the barrier material (C-1) was changed as shown in FIG. 9 and the depth of the groove provided around the opening was 4 mm. A multilayer tank equipped with two molded products was prepared (see FIG. 10), and the gasoline barrier property was measured. The fuel permeation amount in this example was 0.01 (g / 3 months).

Example 7
Two circular openings with a diameter of 70 mm are provided in the body of a 35 L EVOH multilayer tank produced in the same manner as in Example 5, and a concavity with a diameter of 110 mm and a depth of 2 mm is obtained concentrically with the opening. As shown, the tank body was cut out (see FIG. 11). A disc-shaped injection molded product having a diameter of 110 mm and a thickness of 4 mm made of a barrier material (C-1) was mounted in the recess in the same manner as in Example 5 to obtain a multilayer tank having two injection molded products mounted thereon. (See FIG. 12). When the gasoline barrier property of the multilayer tank was measured, the fuel permeation amount was 0.10 (g / 3 months).

Comparative Example 3
A circular opening having a diameter of 110 mm and a thickness of 4 mm made of a barrier material (C-1) is provided in the body of an EVOH multilayer tank having a capacity of 35 L prepared in the same manner as in Example 5 and having a circular opening of 70 mm in diameter. The injection-molded product was heat-sealed to the tank body so that the opening and the center of each injection-molded product overlapped, and the opening was sealed. When the gasoline barrier property of the multilayer tank equipped with two injection molded articles thus obtained was measured, the fuel permeation amount was 0.42 (g / 3 months).

  The multilayer tanks of Examples 5 to 7 having the configuration of the present invention can effectively suppress the permeation of fuel from the cut surface of the opening, and all exhibited excellent gasoline barrier properties. On the other hand, in Comparative Example 3 having no configuration of the present invention, satisfactory gasoline barrier properties were not obtained.

1 Barrier resin (A) layer 2 Thermoplastic resin (B) layer (inner layer)
2 'thermoplastic resin (B) layer (outer layer)
3 Adhesive Resin (Tie) Layer 4 Fuel Container Accessories 5 Barrier Material (C)

Claims (20)

  In a fuel container having a layer made of a barrier resin (A) and an outer layer made of a thermoplastic resin (B) other than (A) and having an opening in the container body, the outer surface around the opening A fuel container, wherein a groove is provided and an inner surface of the groove is covered with a barrier material (C).   In a fuel container having a layer made of a barrier resin (A) and an outer layer made of a thermoplastic resin (B) other than (A) and having an opening in the container body, the outer surface around the opening A fuel container, wherein a groove is provided and the groove is filled with a barrier material (C). The fuel container according to claim 1 or 2, wherein a fuel container accessory is attached to an opening provided in the container body. The fuel container according to claim 3, wherein the groove is filled with an accessory for the fuel container made of a barrier material (C). The fuel container according to any one of claims 1 to 4 , wherein a groove provided on an outer surface around the opening portion surrounds the opening portion without interruption. The fuel container according to claim 5 , wherein the groove has a circular shape. The fuel container according to any one of claims 1 to 7 , wherein the depth of the groove is 0.1 to 0.8 times the container body average total layer thickness (T2). According to claim 1, wherein the depth of the groove is less than 1-fold 0.2-fold or more barrier resin (A) present outside the layer made from which the total thickness of the layer (T1) Fuel container. The fuel container according to any one of claims 1 to 8 , wherein the width of the groove is 0.01 to 5 times the container body average total layer thickness (T2). The fuel container according to any one of claims 1 to 9 , wherein the barrier resin (A) has a gasoline permeation amount of 100 g · 20 µ / m ² · day (a value measured at 40 ° C to 65% RH) or less. The fuel container according to any one of claims 1 to 10 , wherein the barrier resin (A) is at least one selected from the group consisting of a polyvinyl alcohol-based resin, a polyamide, and an aliphatic polyketone. The fuel container according to any one of claims 1 to 11 , wherein the thermoplastic resin (B) is a polyolefin. The fuel container according to claim 12 , wherein the thermoplastic resin (B) is polyethylene having a density of 0.93 or more. The gasoline permeation amount of the barrier material (C) (value measured at 40 ° C.-65% RH) is 0.1 times or less than the gasoline permeation amount of the thermoplastic resin (B) (value measured at 40 ° C.-65% RH). The fuel container according to any one of claims 1 to 13 . The fuel container according to any one of claims 1 to 14 , wherein the barrier material (C) has a gasoline permeation amount of 400 g · 20 µ / m ² · day (a value measured at 40 ° C to 65% RH) or less. Barrier material (C) is a metal foil, epoxy resin, polyvinylidene chloride resin, polyvinyl alcohol resin, polyamide resin, polyester resin, any of claims 1 to 15 is at least one selected from the group consisting of fluorocarbon resin A fuel container according to any one of the above. The fuel container according to any one of claims 1 to 16 , wherein the barrier material (C) covers the cut surface with an adhesive. The fuel container according to any one of claims 1 to 17 , further comprising an intermediate layer made of a barrier resin (A) and an inner / outer layer made of a thermoplastic resin (B) other than (A). The fuel container according to any one of claims 1 to 18, wherein a layer made of the barrier resin (A) and a layer made of the thermoplastic resin (B) other than (A) are laminated via an adhesive resin layer. In the container body, the ratio (T1 / T2) of the total thickness (T1) and the total thickness (T2) of the layers existing outside the layer made of the barrier resin (A) is 45/100 or less. the fuel container according to any one of claims 1 to 19, characterized in.

Images