JP7110498B2 - Method for remanufacturing sheet for article transport container - Google Patents

Description

The present disclosure relates to a method for remanufacturing a sheet for an article transport container.

When transporting precision goods such as automobile parts, from the viewpoint of avoiding damage to the goods due to vibrations during transportation, tray-shaped resin containers molded to fit the shape of the goods to be transported are used ( For example, JP-A-2017-36090). A tray-shaped resin container molded to fit the shape of the article is generally called a "dunage".

However, unless the shape of the dunnage conforms to the shape of the article on which it is placed, the dunnage may not be able to protect the article. Therefore, the conventional dunnage was manufactured by molding a resin material to match the shape of the article to be transported every time the shape of the article changed. Therefore, from the viewpoint of manufacturing cost, disposal cost, storage space, etc., there is a demand for dunnage that can be reused for transportation of articles having different shapes.

In view of the above circumstances, an object of the present disclosure is to provide a method for remanufacturing a sheet for an article transport container that can be repeatedly shaped so as to accommodate articles.

Specific means for solving the above problems include the following aspects.

<1> A first heating step of heating a sheet for an article transport container having a first accommodation shape capable of accommodating a first article at a first temperature;
a flattening step of flattening the first accommodation shape of the article transport container sheet heated at the first temperature;
has
The article transport container sheet contains a polymer that satisfies the following (1) and (2),
The method for remanufacturing a sheet for an article transport container, wherein the first temperature is higher than or equal to the melting point Tm of the polymer and lower than or equal to 280°C.
(1) The intrinsic viscosity [η] measured in a decalin solution at 135°C is 4.0 dL/g or more and 35.0 dL/g or less (2) The melting point Tm is 120°C or more and 140°C or less <2> The method for remanufacturing a sheet for an article transport container according to <1>, wherein the polymer includes an ethylene polymer.
<3> In the flattening step, under atmospheric pressure, the article transport container sheet heated at the first temperature is placed on the surface of the flat surface of the placement section having the flat surface, and 3. The method for remanufacturing a sheet for an article transport container according to claim 1, wherein one accommodation shape is the flat shape.
<4> The method for remanufacturing a sheet for an article transport container according to any one of <1> to <3>, wherein the flat sheet for an article transport container has a flatness of less than 0.04.
<5> a second heating step of heating the flat-shaped article transport container sheet at a second temperature that is equal to or higher than the melting point Tm of the polymer and equal to or higher than 280°C;
a shaping step of shaping the flat shape of the article transport container sheet heated at the second temperature into a second accommodation shape capable of accommodating a second article;
a cooling step of cooling the article transport container sheet shaped into the second accommodation shape;
has
The method for remanufacturing a sheet for an article transport container according to any one of <1> to <4>, wherein the second heating step, the shaping step, and the cooling step are performed in this order.
<6> The method for remanufacturing a sheet for an article transport container according to <5>, wherein in the shaping step, one shaping method of vacuum forming, air pressure forming, and vacuum pressure forming is used.
<7> In the shaping step,
Using a shaping mold having a mold surface corresponding to the second accommodation shape,
contacting the sheet for an article transport container having the flat shape and heated at the second temperature to the mold surface to shape the flat shape into the second housing shape;
In the cooling step, the article conveying container sheet shaped into the second accommodating shape is cooled at least to the above-mentioned The method for remanufacturing a sheet for an article transport container according to <6>, wherein the sheet is cooled to a solidification temperature of the polymer or lower.
<8> In the shaping step,
Using a shaping mold having a mold surface corresponding to the second accommodation shape,
The air between the article-conveying container sheet and the shaping mold is exhausted, and the flat-shaped article-conveying container sheet heated at the second temperature is brought into contact with the mold surface, and the forming a flat shape into the second containing shape;
In the cooling step, the article transporting container sheet shaped into the second housing shape is cooled while contacting the article transporting container sheet shaped into the second housing shape with the mold surface. The method for remanufacturing the sheet for an article transport container according to <6> or <7>.
<9> In the shaping step,
Using a shaping mold having a mold surface corresponding to the second accommodation shape,
The article-conveying-container sheet is pressurized with compressed air, and the flat-shaped article-conveying-container sheet heated at the second temperature is brought into contact with the mold surface to convert the flat-shaped sheet into the second housing. Shaping into shape,
In the cooling step, the article transport container sheet shaped into the second accommodation shape is kept in contact with the mold surface, and the article transport container sheet shaped into the second accommodation shape is kept in contact with the mold surface. The method for remanufacturing a sheet for an article transport container according to <6> or <7>, wherein the sheet is cooled.
<10> The recycling sheet for an article transport container according to any one of <1> to <9>, wherein the first article has a volume of 3.0 cm ³ or more and 1.0×10 ⁶ cm ³ or less. Production method.
<11> The method for remanufacturing a sheet for an article-conveying container according to any one of <1> to <10>, wherein the sheet for an article-conveying container is a dunnage sheet.
<12> A manufacturing history information addition step of adding a mark indicating manufacturing history information to the flat-shaped article transport container sheet,
The method for remanufacturing a sheet for an article transport container according to any one of <1> to <11>, wherein the manufacturing history information adding step is performed after the flattening step.
<13> The manufacturing history information includes at least one selected from the group consisting of product name information, size information, remanufacturing condition information, remanufacturing date and time information, and remanufacturing frequency information,
The item name information indicates the name of the first item,
the size information indicates dimensions of the first article;
the remanufacturing condition information includes the first temperature at which the planarization step was performed;
The remanufacturing date and time information indicates the date and time when the planarization step was performed,
The method for remanufacturing a sheet for an article transport container according to <12>, wherein the remanufacturing number information indicates the cumulative number of times the flattening step has been performed.

According to the present disclosure, there is provided a method for remanufacturing a sheet for an article transport container that can be repeatedly shaped to accommodate articles.

1 is a perspective view showing a dunnage sheet according to a first embodiment of the present disclosure; FIG. 2 is a cross-sectional view taken along section line II of FIG. 1; FIG. Fig. 10 is a perspective view showing a dunnage sheet according to a second embodiment of the present disclosure; FIG. 3 is a cross-sectional view taken along section line IV in FIG. 2 ; 4 is a graph showing measurement results of storage modulus E′ of ethylene-based polymers (PE-1) to (PE-6) at a frequency of 1.59 Hz. 1 is a perspective view of a boat-shaped mold used in Examples. FIG. 1 is a perspective view of a madeleine mold used in Examples. FIG.

Embodiments of the present disclosure will be described below. These descriptions and examples are illustrative of embodiments and do not limit the scope of embodiments.

In this specification, a numerical range represented by "to" means a range including the numerical values before and after "to" as lower and upper limits.
In the numerical ranges described step by step in the present disclosure, the upper limit or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described step by step. . Moreover, in the numerical ranges described in the present disclosure, the upper or lower limits of the numerical ranges may be replaced with the values shown in the examples.

In the present disclosure, each component may contain multiple types of applicable substances. When referring to the amount of each component in the composition in the present disclosure, when there are multiple types of substances corresponding to each component in the composition, unless otherwise specified, the multiple types of substances present in the composition It means the total amount of substance.

In the present disclosure, a sheet is a concept that includes not only what is generally called a sheet but also what is generally called a film.

≪Sheet for goods transportation container≫
The sheet for transporting containers of the present disclosure contains a polymer (hereinafter sometimes referred to as "specific polymer") that satisfies the following (1) and (2).
(1) The intrinsic viscosity [η] measured in a decalin solution at 135°C is 4.0 dL/g or more and 35.0 dL/g or less.
(2) The melting point Tm is 120° C. or higher and 140° C. or lower.

The article transport container sheet of the present disclosure contains a specific polymer.

As a result, the sheet for an article transport container of the present disclosure can be repeatedly shaped so as to accommodate articles. This is presumed for the following reasons.
Since the specific polymer satisfies the above (1), the viscosity average molecular weight (Mv) of the specific polymer calculated from the following equation according to ASTM D4020 is high.
Mv=5.37×10 ⁴ ×[η] ^1.37
In the specific polymer, the relationship between the storage modulus E' of the specific polymer and the temperature has a rubber-like flat region in the range from the melting point Tm of the specific polymer to about 200°C. In the present disclosure, the rubber flat region indicates that the storage elastic modulus E' of the specific polymer takes a substantially constant value independently of temperature at temperatures equal to or higher than the melting point Tm of the specific polymer. In the rubber plateau region, the specific polymer behaves like rubber and has high viscoelasticity.
It is presumed that the reason why the sheet for an article transport container of the present disclosure can be repeatedly shaped so as to accommodate articles is that the specific polymer has a rubber-like flat region in the range of the melting point Tm to about 200°C.
On the other hand, the viscosity-average molecular weight of polymers that do not satisfy (1) above is lower than that of the specific polymer. Therefore, in a polymer that does not satisfy (1) above, the rubber-like flat region does not exist, or even if the rubber-like flat region exists, the temperature range of the rubber-like flat region is very narrow. This is presumably because in polymers that do not satisfy the above (1), the polymer chains do not interpenetrate more deeply than in the specific polymer, and the so-called "entanglement effect" is weak. A sheet for an article transport container that does not contain a specific polymer tends to have high fluidity at a temperature above the melting point, and when accompanied by deformation due to an external force, the potential for recovering the original shape decreases. As a result, a sheet for an article transport container that does not contain a specific polymer cannot be repeatedly shaped to accommodate articles.
The index of the rubber flat area will be described later.

Shaping means imparting a desired shape to a flat-shaped article-conveying-container sheet (hereinafter sometimes referred to as a "flat sheet") without cutting the article-conveying-container sheet.
Articles include, for example, automobile parts; electronic parts; precision instruments; food and beverage containers; Automobile parts include, for example, tires, wheels, chassis parts, interior parts, and the like. The volume per article is not particularly limited, and is preferably 3.0 cm ³ or more and 1.0×10 ⁶ cm ³ or less.

[Shape of sheet for transporting goods]
The shape of the sheet for an article transport container is appropriately selected according to the occasion of use of the sheet for an article transport container, and is, for example, a storage shape capable of storing an article (hereinafter referred to as a "storage shape"), a flat shape, or the like. .

Hereinafter, the sheet for an article transport container having a storage shape may be referred to as an "article transport container".

The accommodation shape means a shape in which an article can be placed and which protects the article during transportation of the article. The storage shape is selected according to the use of the sheet for transporting articles, and includes a fitting shape, an enclosing shape, and the like. The mating shape mates with the article to be placed. The fitting shape is shaped according to the shape of the article to be placed. The enclosure shape encloses the article to be placed with walls.

A flat shape means a shape in which both surfaces of the sheet for an article transport container are substantially flat. In other words, the flatness of the flat article transport container sheet is preferably less than 0.04, more preferably 0.02 or less.
When the flatness of the flat article-conveying container sheet is less than 0.04, the occurrence of warping of the flat article-conveying container sheet is suppressed. Therefore, the article transport container sheet can be easily formed into a desired storage shape. Furthermore, when the sheet for the article-conveying container is stored, the sheet for the article-conveying container is less bulky.
Flatness is measured in the same manner as described in Examples.

[Layer structure and molding method]
The article transport container sheet may have a single layer structure or a laminated structure of two or more layers. In the case where the article transport container sheet has a laminated structure, at least one of the laminated layers, preferably all of the layers, may contain a polymer that satisfies the requirements (1) and (2) of the present disclosure. . Moreover, the sheet for transporting articles may be provided with a release layer, a coating layer, or the like, if necessary.

The size of the article transport container sheet is appropriately adjusted according to the articles and the like to be loaded. For example, when the article transport container sheet is quadrilateral, the length of one side may be 1 m or longer. The average thickness of the article transport container sheet is not particularly limited, but is preferably, for example, 100 μm to 1 cm, more preferably 500 μm to 1 cm, even more preferably 1 mm to 8 mm. In addition, the average thickness of the article-conveying-container sheet means the arithmetic average value of the thicknesses of arbitrary five points in the article-conveying-container sheet.

Examples of the method for forming the sheet for transporting articles include hot press molding, roll press molding, extrusion molding, vacuum molding, air pressure molding, and vacuum air pressure molding. Moreover, a sheet may be obtained by skiving from the molded article obtained by these thermoforming.
In particular, the sheet for an article-conveying container is preferably manufactured into a flat shape by hot-press molding a material (hereinafter referred to as "polymer material") constituting the sheet for an article-conveying container under a predetermined pressure. . As a result, the flat shape is stored as a stable shape in the article conveying sheet. Therefore, even if the flat shape of the flat sheet is formed into the accommodation shape, the sheet for the article transport container, when heated in a temperature range in which the rubber-like flat region exists, will have the shape memory effect of the sheet for the article transport container. Spontaneous shape recovery to the original flat shape is facilitated. Such a phenomenon is not observed, for example, in hollow trays formed by blow molding ultra-high molecular weight polyethylene. In blow molding, even if the hollow tray is reheated above the melting point of the ultrahigh molecular weight polyethylene after blow molding, the hollow tray does not recover its flat shape.
The lower limit of the hot press molding pressure is preferably 0.1 MPa or more, more preferably 1 MPa or more. The upper limit of the hot press molding pressure is preferably 20 MPa or less, more preferably 10 MPa or less. The lower limit of the heating temperature for hot press molding is the melting point Tm or higher of the polymer, preferably 160° C. or higher, more preferably 170° C. or higher. The upper limit of the heating temperature for hot press molding is preferably 280° C. or lower, more preferably 260° C. or lower. The lower limit of the pressing time for hot press molding is preferably 5 minutes or longer, more preferably 10 minutes or longer. The upper limit of the pressing time for hot press molding is preferably 24 hours or less, more preferably 12 hours or less.
The article transport container sheet may be cold-pressed after hot-press molding.
As the pressure of the cooling press, the same ranges as those exemplified as the pressure of the hot press molding can be mentioned. The cooling press pressure may be the same as or different from the hot press molding pressure.
The cooling temperature of the cooling press may be lower than the crystallization temperature of the specific polymer, for example, 100° C. to 200° C. lower than the heating temperature of hot press molding.
The cooling time of the cooling press may be the same range as the heating time of hot press molding. The pressure of the cooling press may be the same as or different from the heating time of hot press molding.

[Analysis method]
If the sheet for transporting goods contains multiple types of specific polymers, or if other polymers other than the specific polymers are included, the specific polymers and other polymers are subject to rheological analysis such as intrinsic viscosity. Each can be specified by an ordinary polymer analysis method such as.

[Properties of specific polymer]
(1) Intrinsic viscosity [η]
The specific polymer has an intrinsic viscosity [η] of 4.0 dL/g to 35.0 dL/g as measured in a decalin solution at 135°C, and can be repeatedly shaped using a sheet for transporting goods. From the point of view of g is more preferred.
If the lower limit of the intrinsic viscosity [η] of the specific polymer is 4.0 dL/g or more, the viscosity average molecular weight of the specific polymer is high. Therefore, the specific polymer has a rubber-like flat region. As a result, the sheet for transporting containers can be shaped repeatedly. The viscosity-average molecular weight can be calculated by a formula according to ASTM D4020 using extremely reduced viscosity [η].
If the lower limit of the intrinsic viscosity [η] of the specific polymer is 35.0 dL/g or less, it is preferable in terms of production aptitude.
The method for measuring the intrinsic viscosity [η] is the same as the method described in Examples.

Techniques for setting the intrinsic viscosity [η] within the above range are not particularly limited, but include, for example, a technique of using hydrogen in combination with the polymerization of the specific polymer; a technique of appropriately adjusting the polymerization temperature; and the like.

(2) Melting point Tm
The melting point Tm of the specific polymer is 120° C. to 140° C., and more preferably 130° C. to 140° C. from the viewpoint of enabling more repeatable shaping using the sheet for transporting containers.
In particular, since the upper limit of the melting point Tm of the specific polymer is 140°C or less, the sheet for transporting containers can be shaped at a heating temperature lower than that in the case where the melting point Tm exceeds 140°C. Therefore, the productivity of the article transport container sheet is excellent.
If the melting point Tm of the specific polymer is 120° C. or higher, it is preferable in terms of heat resistance.
The method for measuring the melting point Tm is the same as the method described in Examples.

(3) Viscosity average molecular weight The viscosity average molecular weight Mv of the specific polymer is preferably 35×10 ⁴ to 650×10 ⁴ , more preferably 120×10 ⁴ to 650×10 ⁴ , still more preferably 120×10 ⁴ to 260. ×10 ⁴ .
When the viscosity-average molecular weight Mv of the specific polymer is within the range of 35×10 ⁴ to 650×10 ⁴ , the sheet for transporting containers can be easily shaped repeatedly.
If the viscosity-average molecular weight Mv of the specific polymer is within the range of 120×10 ⁴ to 650×10 ⁴ , the number of times that the sheet for transporting containers can be shaped increases.
If the viscosity-average molecular weight Mv of the specific polymer is within the range of 120×10 ⁴ to 260×10 ⁴ , the shapeability of the sheet for transporting containers is further improved.
The method for measuring the viscosity-average molecular weight is the same as in Examples.

(4) Density The density of the specific polymer is not particularly limited, and may be appropriately designed according to the desired strength of the article transport container, manufacturing convenience, and the like. For example, the density of the specific polymer is preferably 900 kg/m ³ to 960 kg/m ³ , more preferably 920 kg/m ³ to 960 kg/m ³ , and more preferably 920 kg/m ³ to 950 kg/m ³ . It is even more preferable to have
The method for measuring the density is the same as the method described in Examples.

(5) Storage modulus The lower limit of the storage modulus E' (T1°C) at T1°C (melting point Tm≤T1<180°C) of the specific polymer is preferably 0.5 MPa or more, more preferably 1.0 MPa or more. be.
The upper limit of the storage modulus E' (T1°C) of the specific polymer is preferably 7.0 MPa or less, more preferably 6.0 MPa or less, and even more preferably 5.0 MPa or less.
If the storage elastic modulus E' (T1°C) is 0.5 MPa or more, the specific polymer has high viscoelasticity at T1°C.
The storage elastic modulus E' (T1°C) of the specific polymer is the same as the method described in Examples.

The lower limit of the storage modulus E' (T2°C) of the specific polymer at T2°C (180°C ≤ T2 ≤ 240°C) is preferably 0.5 MPa or more, more preferably 0.8 MPa or more.
The upper limit of the storage modulus E' (T2°C) of the specific polymer is preferably 7.0 MPa or less, more preferably 6.0 MPa or less, and even more preferably 5.0 MPa or less.
If the storage elastic modulus E' (T2°C) is 0.5 MPa or more, the specific polymer has high viscoelasticity at T2°C.
The storage elastic modulus E' (T2°C) of the specific polymer is the same as the method described in Examples.

The lower limit of the ratio of the storage modulus E' (T2°C) to the storage modulus E' (T1°C) of the specific polymer (hereinafter referred to as "(E'(T2°C)/E'(T1°C))") is preferably 0.4 or more, more preferably 0.5 or more.
The upper limit of (E'(T2°C)/E'(T1°C)) is preferably 1.5 or less, more preferably 1.3 or less, and still more preferably 1.2 or less.
If (E' (T2 ° C.) / E' (T1 ° C.)) is in the range of 0.4 or more and 1.5 or less, the storage elastic modulus E' of the specific polymer is substantially constant regardless of temperature. can be regarded as taking a value. Therefore, the specific polymer has high viscoelasticity within the range of T1°C to T2°C.

[Indicator of rubber-like plateau]
In the present disclosure, the presence of a rubber-like flat region means the case where the following (i) and (ii) are satisfied. The absence of a rubber-like flat region means the case where at least one of the following (i) and (ii) is not satisfied.
(i) Each of storage elastic modulus E' (140°C) and storage elastic modulus E' (230°C) is 0.5 MPa or more (ii) "(E'(230°C)/E' (140°C) )” is within the range of 0.4 to 1.5

[Structure of specific polymer]
The specific polymer preferably contains an olefin polymer from the viewpoint of making it easier to obtain a sheet for an article transport container that can be repeatedly shaped so as to accommodate articles. The specific polymer may be used singly or in combination of two or more.

Examples of olefin polymers include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-based polymers, copolymers of ethylene and α-olefins having 2 to 20 carbon atoms, and the like. Ethylene-based polymers; propylene-based polymers such as propylene homopolymers and copolymers of propylene and α-olefins having 2 to 20 carbon atoms; Butene-1 polymers such as copolymers with α-olefins (but excluding butene-1); 4-methyl-1-pentene homopolymers, 4-methyl-1-pentene homopolymers and 2 carbon atoms 4-methyl-1-pentene-based polymers such as copolymers with α-olefins of up to 20 (excluding 4-methyl-1-pentene);

An ethylene-based polymer is a polymer having at least ethylene as a structural unit.
A propylene-based polymer is a polymer having at least propylene as a structural unit.

Among the above, the olefin polymer should include at least one of an ethylene-based polymer and a propylene-based polymer from the viewpoint of making it easier to obtain a sheet for an article transport container that can be repeatedly shaped so as to accommodate articles. is more preferable, it is still more preferable that it contains an ethylene-based polymer, and it is particularly preferable that it contains an ultra-high molecular weight ethylene-based polymer.

As the ultra-high molecular weight ethylene-based polymer, there are two types: a linear type and a crosslinked type.
As one aspect of the present disclosure, the specific polymer may be, for example, an aspect that does not contain a crosslinked ultrahigh molecular weight ethylene polymer and contains a linear ultrahigh molecular weight ethylene polymer.
In particular, a linear ultra-high molecular weight ethylene copolymer is preferably used as a sheet for transporting goods because it has excellent abrasion resistance, low friction, mechanical strength, low-temperature impact resistance, and excellent repeated shapeability. be able to.

The content of the specific polymer is preferably 40% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and 80% by mass to the total amount of the sheet for transporting goods. It is more preferably 100% by mass.

[Other polymers]
The sheet for transporting containers of the present disclosure may contain polymers other than the specific polymer within a range in which the effects of the present disclosure are not impaired.
Other polymers include, for example, thermoplastic resins and thermosetting resins.
Thermoplastic resins include polyvinyl chloride, polyvinylidene chloride, chlorinated polyethylene, chlorinated polypropylene, polyvinylidene fluoride, chlorinated rubber, vinyl chloride-vinyl acetate copolymer, vinyl chloride-ethylene copolymer, vinyl chloride-chloride vinylidene copolymer, vinyl chloride-vinylidene chloride-vinyl acetate terpolymer, vinyl chloride-acrylic acid ester copolymer, vinyl chloride-maleic acid ester copolymer, vinyl chloride-cyclohexylmaleimide copolymer, etc. Halogen resin; petroleum resin, coumarone resin, polystyrene, polyvinyl acetate, acrylic resin, styrene and/or α-methylstyrene and other monomers (e.g. maleic anhydride, phenylmaleimide, methyl methacrylate, butadiene, acrylonitrile, etc.) ) and copolymers (e.g., AS (acrylonitrile styrene) resin, ABS (acrylonitrile butadiene styrene copolymer) resin, ACS (acrylonitrile/chlorinated polyethylene/styrene copolymer) resin, SBS (styrene butadiene styrene block copolymer coalescence) resin, MBS (methyl methacrylate-butadiene-styrene copolymer) resin, heat-resistant ABS resin, etc.); polymethyl methacrylate, polyvinyl alcohol, polyvinyl formal, polyvinyl butyral; polyethylene terephthalate, polybutylene terephthalate, polycyclohexanedimethylene terephthalate, etc. Polyalkylene terephthalate, polyethylene naphthalate, aromatic polyester such as polyalkylene naphthalate such as polybutylene naphthalate, and linear polyester such as polytetramethylene terephthalate; polyhydroxybutyrate, polycaprolactone, polybutylene succinate, polyethylene succinate degradable aliphatic polyesters such as polylactide, polylactic acid, polymalic acid, polyglycolic acid, polydioxane, poly(2-oxetanone); polyamides such as polyphenylene oxide, polycaprolactam and polyhexamethylene adipamide, polycarbonate, polycarbonate/ABS Thermoplastic resins such as resins, branched polycarbonates, polyacetals, polyphenylene sulfides, polyurethanes, cellulose resins, polyimide resins, polysulfones, polyphenylene ethers, polyetherketones, polyetheretherketones, liquid crystal polymers, and blends thereof. can. Thermoplastic resins include isoprene rubber, butadiene rubber, acrylonitrile-butadiene copolymer rubber, styrene-butadiene copolymer rubber, fluororubber, silicone rubber, styrene elastomer, polyester elastomer, nitrile elastomer, nylon elastomer, chloride Elastomers such as vinyl-based elastomers, polyamide-based elastomers, and polyurethane-based elastomers may also be used. The thermoplastic resin may be used singly or in combination of two or more.
Examples of thermosetting resins include epoxy resins, silicone resins, phenol resins, urea resins, unsaturated polyester resins, melamine resins, polyimide resins, polybenzoxazole resins, and urethane resins. A thermosetting resin may be used individually by 1 type, and may be used in combination of 2 or more types.
When other polymers are included, the content of the specific polymer is preferably 95% by mass or more, and 98% by mass or more, relative to the total amount of 100% by mass of the polymer contained in the sheet for transporting containers. more preferably 99.9% by mass or more.

[Filling material]
The sheet for transporting containers of the present disclosure may contain a filler and a coloring agent.
Examples of fillers include inorganic particles such as carbon black, silica, alumina, magnesium and calcium carbonate; natural mineral particles such as talc and mica; and the like. The content of the filler is preferably 1% by mass to 20% by mass, preferably 2% by mass, with respect to the total amount of the sheet for transporting containers, from the viewpoint of maintaining the shape recoverability in the flattening process described later. More preferably, it is up to 10% by mass. Colorants include pigments; dyes; and the like.

≪Goods transport container≫
The article transport container of the present disclosure is a sheet for an article transport container having an accommodation shape.
Since the article transport container of the present disclosure is a shaped product of the article transport container sheet of the present disclosure, it can be repeatedly shaped so as to accommodate the articles.
The article transport container of the present disclosure is a substantially sheet-like article. The thickness of the article transport container may be substantially the same as the average thickness of the article transport container sheet.
The article transport container of the present disclosure protects the transported goods while transporting the transported goods. Examples of goods transport containers include containers, dunnages, and the like. Among them, it is preferable that the article transport container is Dunnage. The container of the present disclosure has the enclosure shape described above.

Hereinafter, when the article transport container is a dunnage, the sheet for the article transport container having the accommodation shape may be referred to as a "dunnage sheet".

≪Seat for Dunnage≫
The dunnage sheet of the present disclosure has the fitting shape described above and contains a specific polymer.
The molding method for obtaining the dunnage sheet is not particularly limited, and known molding methods can be applied. Examples of the forming method include vacuum forming, pressure forming, vacuum pressure forming, TOM (three dimension overlay method) forming, and heat press forming.

The dunnage sheet of the present disclosure will be specifically described with reference to FIGS. 1 to 4. FIG.
First, a dunnage sheet 10A according to a first embodiment of the present disclosure will be described with reference to FIGS. FIG. 1 is a perspective view showing a dunnage sheet 10A according to the first embodiment of the present disclosure. FIG. 2 is a cross-sectional view taken along section line II of FIG.

The Dunnage seat 10A can load four wheels 20A. Wheel 20A is an example of an article.
The dunnage sheet 10A is substantially in the form of a sheet, as shown in FIG. The dunnage sheet 10A has an upper surface TS10A and a lower surface BS10A. The upper surface TS10A and the lower surface BS10A face each other. Wheel 20A is placed on top surface TS10A. As shown in FIG. 2, the thickness T10A of the dunnage sheet 10A is substantially uniform over the entire area of the dunnage sheet 10A.
As shown in FIG. 1, the top surface TS10A has a plane portion TS11A, first convex portions TS12A, four second convex portions TS13A, and four third convex portions TS14A. The planar portion TS11A is substantially planar. Each of the first protrusion TS12A, the four second protrusions TS13A, and the four third protrusions TS14A protrudes upward from the plane portion TS11A. Each of the first protrusions TS12A, the four second protrusions TS13A, and the four third protrusions TS14A is formed to be fittable with the four wheels 20A.
As shown in FIG. 2, the lower surface BS10A has a plane portion BS11A, first convex portions (not shown), four second convex portions BS12A, and four third convex portions (not shown). The plane portion BS11A is substantially planar. Each of the first protrusions, the four second protrusions BS12A, and the four third protrusions of the lower surface BS10A protrude upward from the plane portion BS11A. Plane portion BS11A faces plane portion TS11A of upper surface TS10A. The first convex portion of lower surface BS10A faces first convex portion TS12A. Each of the four second protrusions BS12A faces one corresponding second protrusion TS13A out of the four second protrusions TS13A. Each of the four third protrusions of lower surface BS10A faces one corresponding third protrusion TS14A out of the four third protrusions TS14A.
The first protrusion TS12A, the four second protrusions TS13A, and the four third protrusions TS14A form a fitting shape that can be fitted with the wheel 20A. The fitting shape is an example of the accommodation shape.

Next, a dunnage sheet 10B according to a second embodiment of the present disclosure will be described with reference to FIGS. FIG. 3 is a perspective view showing a dunnage sheet 10B according to the second embodiment. FIG. 4 is a cross-sectional view taken along section line IV in FIG.

The dunnage sheet 10B can be loaded with four flanges 20B. Flange 20B is an example of an article.
The dunnage sheet 10B is substantially in the form of a sheet, as shown in FIG. The dunnage sheet 10B has a top surface TS10B and a bottom surface BS10B. The upper surface TS10A and the lower surface BS10A face each other. The flange 20B rests on the top surface TS10B. As shown in FIG. 4, the thickness T10B of the dunnage sheet 10B is substantially uniform over the entire area of the dunnage sheet 10B.
As shown in FIG. 3, the upper surface TS10B has a plane portion TS11B, four concave plane portions TS12B, and four convex portions TS13B. The planar portion TS11B is substantially planar. Each of the four concave planar portions TS12B is recessed downward from the planar portion TS11B. Each of the four concave planar portions TS12B is substantially planar. Each of the four convex portions TS13B protrudes upward from the concave flat portion TS12B. The four concave plane portions TS12B and the four convex portions TS13B are formed so that the flanges 20B can be fitted.
The lower surface BS10B, as shown in FIG. 4, has a plane portion BS11B, four concave plane portions BS12B, and four convex portions BS13B. The plane portion BS11B is substantially planar. The four concave plane portions BS12B are recessed downward from the plane portion BS11B. The plane portion BS11B faces the plane portion TS11B of the top surface TS10B. Each of the four convex portions BS13B protrudes upward from the concave flat portion BS12B. The concave flat portion BS12B faces the concave flat portion TS12B of the upper surface TS10B. Each of the four protrusions BS13B faces one corresponding protrusion TS13B out of the four protrusions TS13B.
The concave flat portion TS12B and the four convex portions TS13B form a fitting enclosing shape that can be fitted with the flange 20B and surrounds the flange 20B. The fitting enclosing shape is an example of a housing shape.

≪Container≫
A container of the present disclosure has an article and an article transport container (more preferably a dunnage) of the present disclosure.
In the container of the present disclosure, an article is housed in an article-conveying container (more preferably dunnage) which is a molding of the article-conveying-container sheet of the present disclosure.

<<Method for remanufacturing sheet for transporting goods>>
A method for remanufacturing a sheet for an article transport container of the present disclosure includes a first heating step and a flattening step. The first heating process and the planarization process may be performed in this order or may be performed simultaneously.
By performing the first heating step and the flattening step, the sheet for the article transport container having the first accommodation shape capable of accommodating the first article (hereinafter sometimes referred to as "first article transport container"), A flat sheet is obtained. In other words, the remanufacturing method of the present disclosure can remanufacture a sheet for an article transport container that can be repeatedly shaped to accommodate articles.

Examples of the first article include those similar to those exemplified as the article.
Examples of the first accommodation shape include those similar to those exemplified as the accommodation shape.
Examples of the first article-conveying container include those exemplified as the article-conveying container.

[First heating step]
In the first heating step, the first article transport container is heated at a first temperature. As a result, the first article transport container is softened.

The lower limit of the first temperature is equal to or higher than the melting point Tm of the polymer, preferably 10° C. higher than the melting point Tm of the polymer, more preferably 20° C. higher than the melting point Tm of the polymer.
The upper limit of the first temperature is 280° C. or lower, preferably 260° C. or lower, more preferably 240° C. or lower, even more preferably 220° C. or lower, particularly preferably 210° C. or lower, and even more preferably 190° C. or lower. Heat deterioration can be suppressed by setting the first temperature and the heating time within specific ranges.
A rubber plateau region of the polymer exists in the temperature range of the first temperature.
When the first article-conveying container is heated to the melting point Tm or higher of the polymer, if the first article-conveying container is a shaped object of a flat sheet, the first article-conveying container returns to its original flat shape ( sheet) tends to spontaneously recover its shape.
When the first article-conveying container is heated to the first temperature of 280° C. or lower, the polymer in the first article-conveying container does not flow, and the sheet form is maintained.

The heating means in the first heating step is not particularly limited. For example, from the viewpoint of efficient heating according to the shape of the first article transport container, a heating device capable of multifaceted heating at different temperatures may be used. good. Hot air, an infrared heater, or the like can be used as a heating source. In particular, when the thickness of the first article-conveying container is large, the infrared heater is suitable because it can efficiently heat the first article-conveying container in a short period of time due to self-heating accompanying infrared absorption of the first article-conveying container.

The heating time in the first heating step is not particularly limited, and may be appropriately set according to the size, thickness, etc. of the first article transport container. The heating time may be, for example, 1 second to 1 minute, or 1 minute to 10 minutes.

In the first heating step, for example, from the viewpoint of assisting shape recovery from the first accommodation shape to a flat shape, the first article transport container may be heated and pressurized by a hot press such as a mold press process. .

[Planarization process]
In the flattening step, a sheet for an article transport container having a first accommodation shape and heated at a first temperature (hereinafter referred to as a "first article transport container heated at a first temperature") is first accommodated. Flatten the shape. This gives a flat sheet.

Means for flattening the first storage shape (hereinafter also referred to as "flattening means") is appropriately selected according to the size of the first article transport container, and includes, for example, a flat surface mounting method, vacuum processing, gold Mold press processing and the like can be mentioned. Among them, the flattening means is preferably a flat mounting method. If the flattening means is a flat laying method, the first article transport container can be easily flattened. In particular, when the first article-conveying container is a shaped flat sheet, the original flat shape can be restored simply by placing the first article-conveying container heated at the first temperature on a flat surface due to the shape memory effect. recovers its shape spontaneously.
In the flat surface mounting method, the first article transport container heated at a first temperature is mounted on the flat surface of a mounting section having a flat surface under atmospheric pressure, and the first storage shape is formed with no load. Flatten. As a result, the softened first article transport container easily becomes flat.
Atmospheric pressure means a pressure of about 0.08 MPa to 0.12 MPa (approximately 0.8 to 1.2 atmospheres). The first article transport container may be heated to a first temperature when the first accommodation shape is made into a flat shape. When the first housing shape is flattened, the heating time may be, for example, 1 second to 1 minute, or 1 minute to 30 minutes. The higher the heating temperature, the easier it is to shorten the time required to obtain a flat shape.
When the flattening means is vacuum processing, the first article transport container may be heated and flattened under vacuum pressure.
When the flattening means is mold pressing, for example, flattening may be performed by pressing with a mold in the depth direction of the first article transport container.
When the flattening means is stretching, for example, flattening may be performed by stretching in a direction perpendicular to the depth direction of the first article transport container.
Among the above, the flattening means is preferably pressure (compressive force or the like), for example, from the viewpoint of efficiently flattening the first article transport container heated at the first temperature.

In the flattening step, if necessary, the first article-conveying container is heated at the first temperature, and the first article-conveying container is conveyed by applying an external force in at least one of the depth direction and the direction parallel to the main surface. It may also assist in flattening the shape of the container.
The main surface of the first article transport container heated to the first temperature represents a horizontal surface when the container is transported, or a surface where the transporter holds the container. The depth direction in the article transport container heated at the first temperature represents the direction perpendicular to the main surface of the first article transport container.

The flattening step may be a step of flattening the first article-carrying container heated at the first temperature while heating it from the viewpoint of flattening the first article-carrying container more efficiently. In this case, the first heating temperature and the heating time may be the same as the preferred aspects in the first heating step.

[Manufacturing history information addition process]
It is preferable that the method for remanufacturing the sheet for transporting containers of the present disclosure includes a step of adding manufacturing history information. In the manufacturing history information adding step, a mark indicating manufacturing history information (hereinafter referred to as "manufacturing history information mark") is added to the flat sheet. The manufacturing history information addition process is performed after the planarization process.
As a result, a flat sheet with manufacturing history information marks is obtained. Therefore, the user can easily know the manufacturing history information of the article transport container sheet based on the manufacturing history information mark. The number of times an article-container sheet can be shaped is limited and depends on the manufacturing history of the article-container sheet. For example, when selecting a flat sheet to be shaped from among a plurality of flat sheets, the user can select an appropriate flat sheet based on the acquired manufacturing history information.

The manufacturing history information includes, for example, article name information, size information, remanufacturing condition information, remanufacturing date and time information, remanufacturing number information, and the like. Above all, the manufacturing history information preferably includes at least one selected from the group consisting of product name information, size information, remanufacturing condition information, remanufacturing date and time information, and remanufacturing frequency information.
The article name information indicates the name of the stored article. A contained article refers to an article contained in a contained shape before the first heating step and the flattening step are performed. The article name information may include the names of a plurality of stored articles when the number of shaping times of the article transport container sheet is two or more.
The size information indicates the dimensions of the contained item. The size information may include the dimensions of a plurality of stored articles when the number of shaping times of the article transport container sheet is two or more.
The remanufacturing condition information includes the first temperature when the planarization process was performed. The remanufacturing condition information may include, for example, the holding time of the first temperature and the pressurizing conditions when the flattening process is performed. The remanufacturing information may include a plurality of first temperatures when the number of shaping times of the sheet for transporting containers is two or more.
The remanufacturing date and time information indicates the date and time when the planarization process was performed. The remanufacturing date and time information may include a plurality of dates and times when the planarization process was performed when the number of times the planarization process was performed is two or more.

Examples of the manufacturing history information mark include QR code (registered trademark), bar code, character string, and number string. If the production history information mark is a QR code (registered trademark) or barcode, for example, when the mobile terminal reads the production history information mark, the mobile terminal transmits the mark information to the server via the network. The mark information includes the read manufacturing history information mark. The server stores the remanufacturing date/time information in association with the manufacturing history information mark. When receiving the mark information, the server selects the remanufacturing date/time information corresponding to the received manufacturing history information mark from among the plurality of stored remanufacturing date/time information. The server then transmits the selected remanufacturing date and time information to the mobile terminal. A mobile terminal has a display unit. When receiving the remanufacturing date/time information from the server, the mobile terminal causes the display section of the mobile terminal to display the remanufacturing date/time information. This allows the user to easily obtain the manufacturing history information. Examples of the display unit include a liquid crystal display, an organic electroluminescence display, and the like.

The method of adding the manufacturing history information mark to the flat sheet is not particularly limited. For example, a method of printing the manufacturing history information on the surface of the flat sheet, and attaching a label printed with the manufacturing history information mark to the surface of the flat sheet. methods and the like. A method for printing the manufacturing history information mark is not particularly limited, and examples thereof include digital printing, letterpress printing, intaglio printing, planographic printing, and stencil printing. Digital printing includes inkjet printing, electrophotographic printing, and the like. Gravure printing etc. are mentioned as letterpress printing. Examples of intaglio printing include offset printing. Examples of stencil printing include screen printing.

[Accommodation shape forming step]
The method for remanufacturing a sheet for transporting containers according to the present disclosure may further include a second heating step, a shaping step, and a cooling step. A 2nd heating process, a shaping process, and a cooling process (henceforth collectively called "accommodation shape shaping process") are performed in this order. As a result, a sheet for an article transporting container (hereinafter referred to as "second article transporting container") having the second accommodation shape is obtained from the flat sheet. The containing shape forming step is performed after the flattening step. When the method for remanufacturing a sheet for an article transport container of the present disclosure includes the manufacturing history information adding step, the shaping step is performed after the manufacturing history information adding step.

Examples of the second article include those similar to those exemplified as the article. The second item may be the same as or different from the first item.
Examples of the second housing shape include those similar to those exemplified as the housing shape. The second accommodation shape may be the same as or different from the first accommodation shape.
Examples of the second article transport container include those exemplified as the article transport container. The second article carrier may be the same as or different from the first article carrier.

(Second heating step)
The second heating step heats the flat sheet to a second temperature. This softens the flat sheet.

The lower limit of the second temperature is equal to or higher than the melting point Tm of the polymer, preferably 10° C. higher than the melting point Tm of the polymer, more preferably 20° C. higher than the melting point Tm of the polymer.
The upper limit of the second temperature is 280° C. or lower, preferably 260° C. or lower, more preferably 240° C. or lower, even more preferably 220° C. or lower, particularly preferably 210° C. or lower, and even more preferably 190° C. or lower.
The second temperature may be the same as or different from the first temperature.
A rubber plateau region of the polymer exists in the temperature range of the second temperature.

The heating means is not particularly limited, and examples thereof include those exemplified as the heating means in the first heating step. The heating time is not particularly limited, and may be the same as those exemplified as the heating time in the first heating step.

(Shaping process)
In the shaping step, the flat shape of the article transport container sheet heated at the second temperature is shaped into the second housing shape.
The means for shaping the flat shape into the second accommodation shape (hereinafter referred to as "shaping means") is not particularly limited, and a mold manufactured according to the shape of the article, the desired accommodation size, etc. is used. Vacuum forming, pressure forming, vacuum pressure forming, TOM forming, heat press forming, and the like can be mentioned. These shaping means use a shaping die having a mold surface corresponding to the second housing shape (hereinafter sometimes referred to as "second housing mold surface"). Among others, it is preferable to use any one of vacuum forming, pressure forming, and vacuum/pressure forming, which are suitable for forming into a large container shape, as the shaping means.
In vacuum forming, the air between the flat sheet and the shaping mold is evacuated (hereinafter sometimes referred to as "vacuum suction"), and the flat sheet heated at the second temperature is brought into contact with the surface of the second containing mold. to shape the flat shape into a second containing shape.
Air pressure forming is to pressurize a flat sheet with compressed air (hereinafter referred to as "air pressure"), bring the flat sheet heated at a second temperature into contact with the surface of a second housing mold, and convert the flat shape into a second housing shape. shaped into
Vacuum and air pressure molding is performed by performing vacuum suction and air pressure at the same time or at different times, and bringing the flat sheet heated at the second temperature into contact with the surface of the second housing mold to shape the flat shape into the second housing shape. .

(Cooling process)
In the cooling step, the article transport container sheet formed into the second housing shape is cooled. A second article transport container is thus obtained.

In the cooling step, the article conveying container sheet shaped into the second accommodation shape is cooled while the article conveying container sheet shaped into the second accommodation shape is brought into contact with the surface of the second accommodation mold (hereinafter referred to as (referred to as "contact cooling") is preferred. The sheet for transporting articles shaped into the second storage shape tends to return to its original flat shape in a softened state due to its shape memory property. Therefore, rapid solidification by contact cooling facilitates obtaining the second article transport container sheet.
Moreover, it is more preferable that the contact cooling is carried out at least until the temperature becomes equal to or lower than the solidification temperature of the specific polymer. As a result, the second housing mold surface is more reliably transferred to the article transport container sheet formed into the second housing shape. That is, it becomes easier to obtain the second article transport container sheet.

The solidification temperature of the specific polymer is, for example, when the polymer is an ethylene polymer, the crystallization temperature (Tc) measured during the cooling process in addition to the melting point Tm using a differential scanning calorimeter (DSC). 40° C. lower temperature.

The means for cooling the article transport container sheet shaped into the second accommodation shape (hereinafter referred to as "cooling means") is not particularly limited. A method of directly or indirectly contacting the conveying container sheet and the like can be mentioned. Cooling media include cold air and cooling water. Above all, it is preferable that the cooling means cools the article conveying container sheet formed into the second housing shape by bringing a cooling medium into contact with the forming device having the forming means.

[Other processes]
The method for remanufacturing a sheet for an article transport container of the present disclosure may have other steps (hereinafter also simply referred to as "other steps") other than the heating step, the flattening step and the shaping step.
As other steps, for example, the following steps (A) to (D) may be included depending on the shape, size, etc. of the article.
(A) Cut-off step of cutting out the article-conveying-container sheet (B) Extraction step of pressing the article-conveying-container sheet against a mold and extracting it into the shape of the mold (C) Bonding a plurality of article-conveying-container sheets together , Lamination step (D) A coating step of coating the sheet for the article transport container with wax or the like

[Production of ethylene polymer]
Next, a method for producing an ethylene-based polymer, which is an example of the specific polymer, will be described.
In a method for producing an ethylene-based polymer, an olefin is polymerized using an olefin polymerization catalyst. Thereby, an ethylene-based polymer is obtained.
The method for producing an ethylene-based polymer may include, for example, a prepolymerization step and a main polymerization step. The preliminary polymerization step and the main polymerization step are performed in this order.
Hereinafter, the case where the method for producing an ethylene-based polymer includes a prepolymerization step and a main polymerization step will be described.

(Preliminary polymerization step)
In the prepolymerization step, the α-olefin is prepolymerized in the presence of an olefin polymerization catalyst.
The amount of α-olefin is 0.1 to 1000 g, preferably 0.3 to 500 g, particularly preferably 1 to 200 g, per 1 g of solid catalyst.

The catalyst concentration in the preliminary polymerization step may be higher than the catalyst concentration in the main polymerization step.
Olefin polymerization catalysts include solid titanium catalysts and organometallic compound catalysts. The olefin polymerization catalyst may contain other catalyst components as needed.

The solid titanium catalyst preferably contains titanium, magnesium and halogen. A solid titanium catalyst is obtained, for example, by contacting a titanium compound, a magnesium compound, and an electron donor. Titanium compounds include titanium tetrachloride and titanium tetrabromide. Examples of magnesium compounds include magnesium chloride and magnesium bromide. Examples of electron donors include 2-isobutyl-2-isopropyl-1,3-dimethoxypropane and 2,2-diisobutyl-1,3-dimethoxypropane.
The concentration of the solid titanium catalyst is preferably 0.001 mmol to 200 mmol, more preferably 0.01 mmol to 50 mmol, particularly preferably 0.1 mmol to 20 mmol, in terms of titanium atoms per liter of liquid medium. is. Liquid media include, for example, inert hydrocarbon media as described below.

Examples of organometallic compound catalysts include triethylaluminum and triisobutylaluminum.
The amount of the organometallic compound catalyst is preferably such that 0.1 g to 1000 g, more preferably 0.3 g to 500 g of polymer is produced per 1 g of solid titanium catalyst. The amount of the organometallic compound catalyst is preferably 0.1 mol to 300 mol, more preferably 0.5 mol to 100 mol, particularly preferably 1 mol to 50 mol, per 1 mol of titanium atom in the solid titanium catalyst. quantity.

Other catalyst components include polyether compounds and the like. Examples of polyether compounds include 2-isobutyl-2-isopropyl-1,3-dimethoxypropane and 2,2-diisobutyl-1,3-dimethoxypropane.
When the olefin polymerization catalyst contains other catalyst components, the amount of the other catalyst components is preferably 0.1 mol to 50 mol, more preferably 0.5 mol to 30 mol, per 1 mol of titanium atom in the solid titanium catalyst. mol, more preferably 1 to 10 mol.

In the prepolymerization step, an olefin and an olefin polymerization catalyst may be added to the inert hydrocarbon medium to prepolymerize the α-olefin under mild conditions.
Inert hydrocarbon media include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, kerosene; cycloheptane, methylcycloheptane, cyclohexane, methylcyclohexane, methylcyclopentane, cyclooctane , alicyclic hydrocarbons such as methylcyclooctane;
Aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as ethylene chloride and chlorobenzene; and mixtures thereof.
Among them, aliphatic hydrocarbons are preferable as the inert hydrocarbon medium. If an inert hydrocarbon medium is used, prepolymerization is preferably carried out in a batch reactor.

In the prepolymerization step, the α-olefin may be prepolymerized using the α-olefin itself as a solvent, or the α-olefin may be prepolymerized in a substantially solvent-free state. In this case, it is preferable to carry out the preliminary polymerization continuously.

The α-olefin used in the preliminary polymerization may be the same as or different from the olefin used in the main polymerization described below. Specifically, the α-olefin is preferably ethylene or propylene.

The temperature during the prepolymerization is preferably -20 to +100°C, more preferably -20 to +80°C, still more preferably 0 to +40°C.

(Main polymerization step)
In the main polymerization step, main polymerization is performed. Specifically, in this polymerization step, ethylene is polymerized in the presence of an olefin polymerization catalyst.

In this polymerization step, an α-olefin having 3 to 20 carbon atoms may be used in addition to ethylene. Examples of α-olefins having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, Examples include linear olefins such as 1-octadecene and 1-eicosene, and branched olefins such as 4-methyl-1-pentene, 3-methyl-1-pentene and 3-methyl-1-butene. Propylene, 1-butene, 1-pentene and 4-methyl-1-pentene are preferred as these α-olefins.
In this polymerization step, aromatic vinyl compounds such as styrene and allylbenzene; and alicyclic vinyl compounds such as vinylcyclohexane and vinylcycloheptane can also be used together with these α-olefins.

The polymerization method for prepolymerization and main polymerization may be any of bulk polymerization method, liquid phase polymerization method and gas phase polymerization method. Examples of the liquid phase polymerization method include solution polymerization and suspension polymerization.

When the main polymerization takes the form of slurry polymerization, the reaction solvent may be the inert hydrocarbon used in the prepolymerization described above, or an olefin that is liquid at the reaction temperature.

In this polymerization, a solid titanium catalyst, an organometallic compound catalyst, and, if necessary, other catalyst components are used. Other catalyst components include polyether compounds. Examples of polyether compounds include 2-isobutyl-2-isopropyl-1,3-dimethoxypropane and 2,2-diisobutyl-1,3-dimethoxypropane.
The amount of the solid titanium catalyst is preferably 0.0001 to 0.5 mmol, more preferably 0.005 to 0.1 mmol in terms of titanium atoms per liter of polymerization volume.
The amount of the organometallic compound catalyst is preferably 1 mol to 2000 mol, more preferably 5 mol to 500 mol, per 1 mol of the titanium atom in the catalyst component in the polymerization system.
When other catalyst components are used, the amount of the other catalyst components used is preferably 0.001 mol to 50 mol, more preferably 0.01 mol to 30 mol, particularly preferably 0.01 mol to 30 mol, relative to the organometallic compound catalyst. 0.05 mol to 20 mol.

If this polymerization is carried out in the presence of hydrogen, it becomes possible to control the molecular weight of the obtained ethylene polymer. Therefore, in this polymerization, it is preferable to polymerize ethylene in the presence of hydrogen. The reason for this is not clear at present, but by carrying out the polymerization in the presence of hydrogen, the chain transfer reaction by olefins such as ethylene is suppressed, and the ethylene polymer particles having a saturated bond structure at the molecular ends, that is, molding It is presumed that this is because a stable ethylene-based polymer is obtained which does not easily deteriorate during the process.

In the main polymerization, the olefin polymerization temperature is preferably 20°C to 200°C, more preferably 30°C to 100°C, still more preferably 50°C to 90°C. The pressure is preferably normal pressure to 10 MPa, more preferably 0.20 MPa to 5 MPa. The polymerization reactor may be batch type, semi-continuous type, continuous type, or the like.

Furthermore, the polymerization can be carried out in two or more stages by changing the reaction conditions.
Specifically, the polymerization step may have step (a) and step (b).
In step (a), an ethylene-based polymer having a limiting viscosity [η] within the first range is produced. The first range is preferably 2 dl/g to less than 10 dl/g, more preferably 3 dl/g to less than 10 dl/g, even more preferably 5 dl/g to less than 10 dl/g.
In step (b), an ethylene polymer having a limiting viscosity [η] within the second range is produced. The second range is preferably 5 dl/g to 35 dl/g, more preferably 7 dl/g to 33 dl/g, still more preferably 10 dl/g to 33 dl/g, particularly preferably 15 dl/g to 32 dl/g. It is below.
However, the intrinsic viscosity [η] of the ethylene polymer obtained in step (a) (hereinafter referred to as "ethylene polymer (a)") and the ethylene polymer obtained in step (b) (hereinafter referred to as Different from the [η] of the ethylene polymer (b), and further compared to the intrinsic viscosity [η] of the ethylene polymer (a), [η of the ethylene polymer (b) ] is preferably high.
Furthermore, it is more preferable to carry out under the condition that [η] of the ethylene polymer produced in the first stage is lower than the intrinsic viscosity [η] of all the ethylene polymers produced in the second and subsequent stages. That is, it is preferable that [η] of the ethylene-based polymer produced in the first stage is lower than the intrinsic viscosity [η] of the finally obtained ethylene-based polymer. The preferred range of the intrinsic viscosity [η] of the ethylene polymer produced in the first stage is the same as the range of [η] of the ethylene polymer obtained in step (a) above.

Further, the mass ratio of the ethylene polymer (a) and the ethylene polymer (b) depends on the intrinsic viscosity generated in each step, but the ratio of the ethylene polymer (a) is 0 to 50% by mass. , the ratio of the ethylene polymer (b) is 100 to 50% by mass. A preferred mass ratio of the ethylene polymer (a) and the ethylene polymer (b) is 5/95 to 50/50, more preferably 10/90 to 40/60, still more preferably 15/85 to 40/60. is. This mass ratio can be determined by measuring the amount of ethylene absorbed in each process, sampling a small amount of the resin obtained in each process and specifying a specified amount, and determining the mass, slurry concentration, content of the catalyst component in the resin, etc. can be determined by calculating the amount of resin produced.

When a catalyst containing a solid titanium catalyst is used to polymerize ethylene and optionally other olefins, the polymerization reaction occurs at catalytically active sites in the solid titanium catalyst component. It is presumed that the polymer produced in the early stage of the polymerization reaction is unevenly distributed on the surface of the particles, and the polymer produced in the late stage of the polymerization reaction is unevenly distributed in the interior of the particles. It is considered to be a phenomenon similar to tree rings. Therefore, when the ethylene polymer is produced by dividing the reaction conditions into two or more stages, the intrinsic viscosity [η] of the ethylene polymer produced in the first stage is the [η ], there is a high possibility that a relatively low-molecular-weight polymer is present on the particle surface.

In this polymerization step, a batch reactor, a continuous reactor, or the like may be used. When the main polymerization process is multistage as described above, it is preferable to employ a batch type reactor. The particles of the ethylene-based polymer (a) and the ethylene-based polymer (b) obtained using a batch reactor have little variation among particles.

The ethylene-based polymer thus obtained may be a homopolymer, a random copolymer, a block copolymer, or the like. Preferably, the ethylene-based polymer is an ethylene homopolymer from the viewpoint of easily obtaining a polymer having a high degree of crystallinity.

The method for producing an ethylene-based polymer may have a heating step in addition to the preliminary polymerization step and the main polymerization step. A heating step is performed after the main polymerization step.
In the heating step, the heating temperature is maintained at 100° C. or higher and below the melting point of the ethylene-based polymer in a gas phase atmosphere.
The heating temperature in the heating step is preferably 100°C to 140°C, more preferably 105°C to 140°C, still more preferably 110°C to 135°C. The heating time in the heating step is preferably 15 minutes to 24 hours, more preferably 1 to 10 hours, still more preferably 1 to 4 hours. Examples of the method for heating the ethylene-based polymer include a method using an oven and a method using a dryer. Through such steps, an ethylene polymer having a higher degree of crystallinity can be obtained.

Moreover, when the polymerization method of the main polymerization step is a liquid phase polymerization method, the method for producing the ethylene-based polymer preferably has a drying step in addition to the prepolymerization step and the main polymerization step.
The heating temperature in the drying step is preferably 90°C to 140°C, more preferably 95°C to 140°C, still more preferably 95°C to 135°C, and particularly preferably 95°C to 130°C. The heating time in the drying step is preferably 15 minutes to 24 hours, more preferably 1 to 10 hours, still more preferably 1 to 4 hours.

The ethylene-based polymer may be a commercial product. Commercially available products include, for example, Hi-Zex Million (registered trademark) 030S, 145M, 240S, 320MU, 630M, Neurite (registered trademark) NL-W, and the like.

Examples of the present disclosure will be described below, but the present disclosure is not limited to the following examples.

<<Preparation of polymer material>>
Ethylene-based polymers (PE-1) to (PE-6) were prepared as polymer materials.
Ethylene-based polymers (PE-1) to (PE-5) of Examples were produced according to WO2008/013144.
(PE-1) ultra-high molecular weight polyethylene (intrinsic viscosity 4.9 dl/g, melting point 132°C)
(PE-2) ultra-high molecular weight polyethylene (intrinsic viscosity 14.4 dl/g, melting point 132°C)
(PE-3) ultra-high molecular weight polyethylene (intrinsic viscosity 19.9 dl/g, melting point 133°C)
(PE-4) ultra-high molecular weight polyethylene (intrinsic viscosity 30.5 dl/g, melting point 133° C.)
(PE-5) ultra-high molecular weight polyethylene (intrinsic viscosity 14.0 dl/g, melting point 131° C.)
(PE-6) high density polyethylene (intrinsic viscosity 3.3dl/g, melting point 128°C)

[Measurement of ethylene polymer]
The intrinsic viscosity [η], viscosity-average molecular weight Mv, melting point Tm, crystallization temperature Tc, density, and storage elastic modulus E′ of the ethylene polymers (PE-1) to (PE-6) were measured as follows. rice field. Table 1 shows measurement results of intrinsic viscosity [η], viscosity average molecular weight Mv, melting point Tm, crystallization temperature Tc, density, and storage elastic modulus E′.

<Method for measuring intrinsic viscosity [η]>
The intrinsic viscosity [η] was measured at 135° C. in a decalin solvent using an Ubbelohde viscometer as a measuring device.
Specifically, about 20 mg of powdered polymeric material was dissolved in 25 ml of decalin. After that, using an Ubbelohde viscometer, the specific viscosity η _sp was measured in an oil bath at 135°C. After adding 5 ml of decalin to this decalin solution for dilution, the specific viscosity η _sp was measured in the same manner as described above. This dilution operation is repeated twice, and the intrinsic viscosity [η] (unit: _dl /g ).
[η]=lim(ηsp/C) (C→0) Equation 1

<Method for measuring viscosity average molecular weight Mv>
The viscosity average molecular weight Mv was measured according to ASTM D4020.

<Measurement method of crystallization temperature (Tc) and melting point (Tm)>
Crystallization temperature (Tc) and melting point (Tm) were measured using a differential scanning calorimeter (DSC) under the following conditions.
Specifically, about 5 mg of the polymer material is sealed in an aluminum pan for measurement of a differential scanning calorimeter (DSC220C type) manufactured by Seiko Instruments Inc., and heated from 30 ° C. to 200 ° C. at 10 ° C./min. did. It was held at 200°C for 10 minutes to completely melt the polymeric material, then cooled to 30°C at 10°C/min. The temperature at which an exothermic peak occurred during this cooling process was defined as the crystallization temperature (Tc).
It was then placed at 30°C for 5 minutes and then heated a second time to 200°C at 10°C/min. The obtained temperature (° C.) showing an endothermic peak in the second heating was taken as the melting point (Tm) of the polymer material. When multiple peaks were detected, the peak of the component corresponding to the polymeric material with the highest weight-average molecular weight was adopted as the melting point (Tm) of the polymeric material.

<Method for measuring density>
Density was measured according to ASTM D1505.

<Method for measuring storage modulus>
Using a solid viscoelasticity measuring device ("RSA-III" manufactured by TA Instruments), a test piece (thickness: 2 mm) made of a polymer material was heated from 25 ° C. to 230 under the following conditions. The storage modulus E' and the loss modulus E'' were measured in the temperature range up to °C.
・Measurement mode: Tensile ・Frequency: 1.59Hz
・Strain amount: 0.1%
・Temperature increase rate: 4°C/min ・Atmosphere: Nitrogen

Fig. 5 shows the measurement results of the storage modulus E' of the ethylene polymers (PE-1) to (PE-6) in the temperature range of 30°C to 230°C.

[Example 1]
≪Manufacturing of sheet for transporting goods≫
Ethylene-based polymer (PE-1) is heat-press-molded under vacuum (heating temperature 230° C., pressure 2 MPa, pressure After 10 minutes), a sheet (size: 350 mm x 350 mm) was obtained by cooling press (cooling temperature: 30°C, pressure: 2 MPa, pressing time: 10 minutes). Next, the obtained sheet was cut into A4 size (210 mm×297 mm) to obtain a first flat sheet. The average thickness of the first flat sheet obtained was the average thickness shown in Table 1.

≪Evaluation of repeated shaping≫
(1) A flat sheet was formed into a desired three-dimensional shape using a 3D-type vacuum heat-pressing device (manufactured by Mikado Technos Co., Ltd.). The vacuum heat-pressing device includes a flat upper board and a lower board having a rectangular parallelepiped cavity space. The upper board is positioned vertically above the lower board.
A mold 1 (see FIG. 6, material: stainless steel, deep-drawn product, mass: 19 g) was placed in the center of the lower platen. The mold surface S1 of the mold 1 was boat-shaped as shown in FIG. The maximum length of the mold 1 was 110 mm. The maximum height of the mold 1 was 14 mm.
After that, the upper panel temperature was set to 200°C, and the lower panel temperature in the vertical direction was set to 60°C. The first flat sheet was then preheated at 200° C. for 10 minutes in a heating oven. The first flat sheet was then clamped between the upper platen and the lower platen. In this state, the first flat sheet was left for 300 seconds (second heating step).
Then, the space surrounded by the upper board and the lower board was evacuated for 30 seconds. After that, only the space surrounded by the upper plate and the first flat sheet was returned to the atmospheric pressure. As a result, the flat shape of the first flat sheet was shaped into the first fitting shape along the shape of the mold 1 (shaping step).
For cooling, it was held for 300 seconds (while bringing the article transport container sheet formed into the first fitting shape into contact with the mold surface S1 of the mold 1) in a vacuum decompressed state (cooling step). At this time, the sheet for conveying containers formed into the first fitting shape has a temperature of 120° C. (crystallization temperature Tc) or lower.
After that, the inside of the apparatus was released to the atmospheric pressure, the mold was opened, and the dunnage 1 having the first fitting shape was obtained (accommodating shape shaping step).
The obtained Dunnage 1 was evaluated for the following first shapeability.
(2) Next, the obtained Dunnage 1 was placed on a flat surface in a heating oven (at a temperature of 200°C) and heated for 10 minutes without load to spontaneously change the first fitting shape into a flat shape. (First heating step and flattening step). It was then cooled to room temperature to obtain a second flat sheet.
The obtained second flat sheet was evaluated for the following first shape recovery property and first flatness.
(3) A mold 2 (see FIG. 7, material: aluminum alloy, deep drawn product, mass: 17 g) was used instead of the mold 1 in the same manner as in step (1) above. A dunnage 2 having two fitting shapes was obtained (accommodating shape shaping step). The mold surface S2 of the mold 2 was of the Madeleine type, as shown in FIG. The maximum length of the mold 2 was 95 mm. The maximum height of the mold 2 was 15 mm.
The obtained Dunnage 2 was evaluated for the following second shapeability.
(4) Next, the obtained Dunnage 2 was placed on a flat surface in a heating oven (at a temperature of 200°C) and heated for 10 minutes without load to spontaneously change the second fitting shape to a flat shape ( first heating step and flattening step). This gave a third flat sheet.
The obtained third flat sheet was evaluated for the following second shape recovery property and second flatness.

Table 1 shows the evaluation results of the first shapeability, the first shape recovery, the first flatness, the second shapeability, the second shape recovery, and the second flatness.

≪Evaluation of the first shapeability≫
The appearance of Dunnage 1 was visually observed. The first formability of Dunnage 1 was evaluated according to the following criteria. Acceptable ratings for primary excipient properties are A or B.

<First formability evaluation criteria>
A: The shape of the mold 1 is clearly formed.
B: The shape of the mold 1 is generally formed and is within the allowable range.
C: Forming into the shape of the mold 1 is insufficient.

<<Evaluation of first shape recovery>>
The appearance of the second flat sheet was visually observed. The first shape recoverability of the second flat sheet was evaluated according to the following criteria. Acceptable ratings for primary shape recovery are A or B.

<Evaluation Criteria for First Shape Recovery>
A: No imprint of the mold 1 was observed on the surface of the second flat sheet.
B: Slight traces of shaping by the mold 1 were observed on the surface of the second flat sheet, but within the allowable range.
C: Forming traces of the mold 1 were clearly seen on the surface of the second flat sheet.

<<Evaluation of first flatness>>
The flatness of the second flat sheet was calculated. Flatness is represented by (Hmax/L). Based on the calculated flatness value, the first flatness was evaluated according to the following criteria. Acceptable ratings for first flatness are A or B.
Specifically, the flatness of the second flat sheet is calculated as follows.
The second flat sheet was placed on the surface of a rigid flat surface measurement table such that the first major surface of the second flat sheet faced upward. Then, using a height gauge, the maximum height H1 of the second flat sheet from the surface of the plane measuring table was measured. Then, the second flat sheet was placed on the surface of the flatness measuring table so that the second main surface of the second flat sheet faced upward. A height gauge was used to measure the maximum height H2 of the second flat sheet from the surface of the plane measuring table. The higher one of the height H1 and the height H2 obtained by measurement was defined as Hmax.
Let L be the length of the longest straight portion in the plane of the second flat sheet. Specifically, for the A4 size second flat sheet, L is the length of the diagonal line of the second flat sheet (approximately 364 cm).
Finally, dividing Hmax by L gives the flatness expressed as (Hmax/L).

<Evaluation Criteria for First Flatness>
A: The flatness (Hmax/L) of the second flat sheet is 0.04 or less B: The flatness (Hmax/L) of the second flat sheet is more than 0.04 and less than 0.08 C: The flatness of the second flat sheet Flatness (Hmax/L) is 0.08 or more

≪Evaluation of the second shapeability≫
The appearance of Dunnage 2 was visually observed. The second formability of Dunnage 2 was evaluated according to the following criteria. Acceptable ratings for secondary excipients are A or B.

<Evaluation Criteria for Second Formability>
A: The shape of the mold 2 is clearly formed.
B: The shape of the mold 2 is generally formed and is within the allowable range.
C: Forming into the shape of the mold 2 is insufficient.

<<Evaluation of second shape recovery>>
The appearance of the third flat sheet was visually observed. The second shape recovery property of the third flat sheet was evaluated according to the following criteria. Acceptable ratings for secondary shape recovery are A or B.

<Evaluation Criteria for Second Shape Recovery>
A: No shaping traces of mold 1 and mold 2 were observed on the surface of the third flat sheet.
B: Slight traces of shaping by the molds 1 and 2 were observed on the surface of the third flat sheet, but within the allowable range.
C: Forming traces of mold 1 and mold 2 were clearly observed on the surface of the third flat sheet.

<<Evaluation of the second flatness>>
The flatness of the third flat sheet was calculated. Based on the calculated flatness value, the second flatness was evaluated according to the following criteria. Acceptable ratings for secondary flatness are A or B.
The flatness (Hmax/L) of the third flat sheet was obtained in the same manner as the flatness (Hmax/L) of the second flat sheet.

<Evaluation Criteria for Second Flatness Evaluation>
A: The flatness (Hmax/L) of the third flat sheet is 0.04 or less B: The flatness (Hmax/L) of the third flat sheet is more than 0.04 and less than 0.08 C: The flatness of the third flat sheet Flatness (Hmax/L) is 0.08 or more

[Examples 2 to 5, Comparative Example 1]
As the polymer material, instead of the ethylene polymer (PE-1), the ethylene polymers (PE-2, PE-3, PE-4, PE-5) shown in Table 1 were subjected to vacuum The heating temperature was set to 260° C. in hot press molding, and for the ethylene copolymer (PE-6), the heating temperature was set to 230° C. in hot press molding under vacuum to produce the first flat sheet. A first flat sheet, a dunnage 1, a second flat sheet, a dunnage 2 and a third flat sheet were obtained in the same manner as in Example 1.
For the dunnage 1, the second flat sheet, the dunnage 2, and the third flat sheet obtained, in the same manner as in Example 1, the first shapeability, the first shape recovery, the first flatness, the second shape Each of the elasticity, the second shape recovery property, and the second flatness was evaluated. These evaluation results are shown in Table 1.

As shown in Table 1, the sheets for transporting containers of Examples 1 to 5 contain an ethylene-based polymer. The intrinsic viscosities [η] of the ethylene-based polymers of Examples 1 to 5 were 4.0 dL/g or more and 35.0 dL/g or less. Furthermore, the melting points Tm of the ethylene polymers of Examples 1 to 5 were 120° C. or higher and 140° C. or lower. Therefore, "(E'(230°C)/E'(140°C))" of the ethylene polymers of Examples 1 to 5 was within the range of 0.4 to 1.5. In other words, as shown in FIG. 5, it was found that the ethylene-based polymers of Examples 1-5 had a rubbery plateau between about 140.degree. C. and 230.degree.
For Examples 1-5, Dunnage 1 was placed on a flat surface in a heating oven and heated to 200° C., which is within the temperature range where a rubbery flat area exists. As a result, the boat-like shape of Dunnage 1 was spontaneously flattened to obtain a second flat sheet. The obtained second flat sheets of Examples 1 to 5 were evaluated as "A" for the first shape recovery property and the first flatness. As a result, it was found that in Examples 1 to 5, it was possible to repeatedly shape the sheet for an article transport container so that articles could be accommodated.

Furthermore, in Examples 1 to 5, the sheet for transporting articles was heated at 200° C., which is within the temperature range in which the rubber-like flat regions exist, to obtain dunnage 2 and third flat sheets. Therefore, the evaluation of the second formability of Dunnage 2 and the second shape recovery and second flatness of the third flat sheet was "A" or "B". As a result, it was found that in Examples 1 to 5, the sheet for transporting containers can be shaped two or more times.

As shown in Table 1, the article transport container sheet of Comparative Example 1 contains an ethylene-based polymer. The intrinsic viscosity [η] of the ethylene polymer of Comparative Example 1 was less than 4.0 dL/g. Therefore, "(E'(230°C)/E'(140°C))" of the ethylene-based polymer of Comparative Example 1 was less than 0.4. In other words, as shown in FIG. 5, it was found that the ethylene-based polymer of Comparative Example 1 did not have a rubbery flat region in the temperature range of 140° C. or higher.
In Comparative Example 1, a second flat sheet was obtained by placing Dunnage 1 on a flat surface in a heating oven and heating at 200° C., which is outside the temperature range where rubbery flat regions exist. Therefore, the obtained second flat sheet was evaluated as "C" for the first shape recoverability and the first flatness. As a result, it was found that in Comparative Example 1, it was not possible to repeatedly shape the sheet for an article transport container so as to accommodate articles.

The disclosure of Japanese Patent Application No. 2019-171746 filed on September 20, 2019 is incorporated herein by reference in its entirety.
All publications, patent applications and technical standards mentioned herein are to the same extent as if each individual publication, patent application and technical standard were specifically and individually noted to be incorporated by reference. incorporated herein by reference.

Claims (13)

a first heating step of heating a sheet for an article transport container having a first accommodation shape capable of accommodating a first article at a first temperature;
a flattening step of flattening the first accommodation shape of the article transport container sheet heated at the first temperature;
has
The article transport container sheet contains a polymer that satisfies the following (1) and (2),
The method for remanufacturing a sheet for an article transport container, wherein the first temperature is higher than or equal to the melting point Tm of the polymer and lower than or equal to 280°C.
(1) Intrinsic viscosity η measured in decalin solution at 135°C is 4.0 dL/g or more and 35.0 dL/g or less (2) Melting point Tm is 120°C or more and 140°C or less 2. The method for remanufacturing a sheet for an article transport container according to claim 1, wherein said polymer comprises an ethylene polymer. In the flattening step, under atmospheric pressure, the article transport container sheet heated at the first temperature is placed on the surface of the flat surface of the placement section having the flat surface to obtain the first storage shape. 3. The method for remanufacturing a sheet for an article transport container according to claim 1 or 2, wherein the flat shape is formed. 4. The method for remanufacturing an article-conveying-container sheet according to claim 1, wherein the flatness of the article-conveying-container sheet is less than 0.04. a second heating step of heating the flat sheet for an article transport container at a second temperature that is equal to or higher than the melting point Tm of the polymer and equal to or lower than 280°C;
a shaping step of shaping the flat shape of the article transport container sheet heated at the second temperature into a second accommodation shape capable of accommodating a second article;
a cooling step of cooling the article transport container sheet shaped into the second accommodation shape;
has
The method for remanufacturing a sheet for an article transport container according to any one of claims 1 to 4, wherein the second heating step, the shaping step, and the cooling step are performed in this order. 6. The method for remanufacturing a sheet for an article transport container according to claim 5, wherein in the shaping step, one shaping method of vacuum forming, air pressure forming, and vacuum pressure forming is used. In the shaping step,
Using a shaping mold having a mold surface corresponding to the second accommodation shape,
contacting the sheet for an article transport container having the flat shape and heated at the second temperature to the mold surface to shape the flat shape into the second housing shape;
In the cooling step, the article conveying container sheet shaped into the second accommodating shape is cooled at least to the above-mentioned 7. The method for remanufacturing a sheet for an article transport container according to claim 6, wherein the sheet is cooled to a temperature below the solidification temperature of the polymer. In the shaping step,
Using a shaping mold having a mold surface corresponding to the second accommodation shape,
The air between the article-conveying container sheet and the shaping mold is exhausted, and the flat-shaped article-conveying container sheet heated at the second temperature is brought into contact with the mold surface, and the forming a flat shape into the second containing shape;
In the cooling step, the article transporting container sheet shaped into the second housing shape is cooled while contacting the article transporting container sheet shaped into the second housing shape with the mold surface. The method for remanufacturing the article transport container sheet according to claim 6 or 7. In the shaping step,
Using a shaping mold having a mold surface corresponding to the second accommodation shape,
The article-conveying-container sheet is pressurized with compressed air, and the flat-shaped article-conveying-container sheet heated at the second temperature is brought into contact with the mold surface to convert the flat-shaped sheet into the second housing. shaping into shape,
In the cooling step, the article transport container sheet shaped into the second accommodation shape is kept in contact with the mold surface, and the article transport container sheet shaped into the second accommodation shape is kept in contact with the mold surface. The method for remanufacturing a sheet for an article transport container according to claim 6 or 7, wherein the sheet is cooled. The method for remanufacturing a sheet for an article transport container according to any one of claims 1 to 9, wherein the first article has a volume of 3.0 cm ³ or more and 1.0 x 10 ⁶ cm ³ or less. The method for remanufacturing a sheet for an article-conveying container according to any one of claims 1 to 10, wherein the sheet for an article-conveying container is a dunnage sheet. a production history information addition step of adding a mark indicating production history information to the flat article transport container sheet,
The method for remanufacturing a sheet for an article transport container according to any one of claims 1 to 11, wherein said manufacturing history information addition step is performed after said flattening step. The manufacturing history information includes at least one selected from the group consisting of product name information, size information, remanufacturing condition information, remanufacturing date and time information, and remanufacturing frequency information,
The item name information indicates the name of the first item,
the size information indicates dimensions of the first article;
the remanufacturing condition information includes the first temperature when the planarization step was performed;
The remanufacturing date and time information indicates the date and time when the planarization step was performed,
13. The method for remanufacturing a sheet for an article transport container according to claim 12, wherein said remanufacturing number information indicates a cumulative number of times said flattening step has been performed.

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