JP2007062084A - Laminate for molding container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminate for molding a food container usable in an electronic oven and capable of providing a molded product having good handleability after the heating of the container, good heat insulating properties, heat resistance, and also good impact resistance. <P>SOLUTION: In the laminate for molding a container produced by laminating a long fiber nonwoven fabric on a synthetic resin sheet capable of being molded into a container by thermoforming, the long fiber nonwoven fabric satisfies an average stress at 5% elongation of 0.01-60 N/5 cm, an average elongation at break of 20% or above, a basis weight of 20-180 g/m<SP>2</SP>and a thickness of 0.16 mm or above. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laminate for forming a container suitable for production of a food container used in a range, an oven or the like. More specifically, the present invention relates to a laminate suitable for molding a container such as a tray having excellent heat resistance, handling properties, heat insulation properties, and heat retention properties, and further relates to a laminate excellent in recyclability.

In recent years, in containers used for cooking in a microwave oven and oven, polypropylene resin blended with calcium carbonate particles (PPF), heat resistant polyester, and the like are used.
When these containers are taken out from the resin, since the temperature of the contents is high, it is hot to hold the container, so there is a drawback that handling properties are very poor. That is, in the case of PPF, since the heat resistance rigidity is low, there is a problem that when the container is taken out from the resin, the contents are liable to spill and the contents are easily spilled, and the contents are easily cooled. Although there is little drooping, there is a drawback that it is difficult to hold because the temperature of the container when taken out of the range is high.
In order to improve these, there is a double bottom type container using paper or the like, but the cost is high, and it takes time and effort to separate plastic and paper at the time of disposal.
In recent years, recyclability has been demanded, and reuse of resins such as used containers and punched scraps has been demanded. If the materials are not uniform, it is difficult to recycle scraps and scraps.
Patent Document 1 discloses a technique of using a heat insulating material that laminates a heat-shrinkable film and a non-woven fabric for a beverage bottle. However, when used as a food tray, the film shrinks after heat treatment with a resin or the like. There is a problem that the tray is deformed.
Patent Document 2 has an attempt to use a polyester resin foam sheet, but it is difficult to produce a stable foam sheet with a thin thickness of less than 1 mm, and the molding method is limited. There are drawbacks such as warping at the ends later, making it difficult to use for the production of container-formed laminates.
JP 2005-35120 A JP-A-8-183871

  As described above, a molded body made of the conventional PPF or the heat-resistant polyester resin sheet cannot have the heat insulating property, handling property, heat resistance, and impact resistance. Based on the above background, the present invention provides a molded product having excellent moldability of a food container that can be used in a microwave oven and an oven, and having handling properties after heating the container, heat insulation properties, heat resistance, and impact resistance. An object of the present invention is to provide a container-forming laminate that can be used.

That is, the present invention is as follows.
1. A laminate for container molding in which a long-fiber nonwoven fabric is laminated on a synthetic resin sheet that can be molded by thermoforming, and the long-fiber nonwoven fabric has an average stress of 0.01 to 60 N / 5 cm at 5% elongation, average elongation at break of 20% or more, basis weight 20~180g / m ^2, the container-forming laminated sheet which satisfies the above thickness 0.16 mm.
2. The laminated body for container molding according to the first aspect, wherein the embossed area ratio of the long fiber nonwoven fabric is 10% or more.
3. The laminate for container molding according to claim 1 or 2, wherein the synthetic resin sheet and the long-fiber nonwoven fabric are mainly composed of aromatic polyester.
4). The long fiber nonwoven fabric is composed of continuous fibers having an aromatic polyester (melting point: Tm ₁ ) and an aromatic copolymer polyester (melting point: Tm ₂ = 150 ° C. to (Tm ₁ -20 ° C.)). The laminate for forming a container according to any one of the first to third aspects.
5. The ratio of the aromatic polyester (melting point: Tm ₁ ) and the aromatic copolymer polyester (melting point: Tm ₂ = 150 ° C. to (Tm ₁ -20 ° C.)) is 100: 0 to 40:60 (mass ratio). 4. The container-molding laminate according to claim 4, wherein the laminate is for container molding.
6). 5. The container-forming laminate according to claim 4, wherein the continuous fibers of the long-fiber nonwoven fabric are core-sheath type composite fibers in which the aromatic polyester is a core and the aromatic copolymer polyester is arranged in a sheath.
7). The container molding according to any one of 1 to 6, wherein at least one film selected from polybutylene terephthalate, polytrimethylene terephthalate and polyester elastomer is laminated on at least one side of the long-fiber nonwoven fabric. Laminated body.
8). 2. The container-forming laminate according to claim 1, wherein the surface of the long-fiber nonwoven fabric opposite to the synthetic resin sheet is printed.

  According to the present invention, since the laminate is excellent in mold followability, containers such as trays and cups can be molded with good moldability, and handling properties, heat insulation properties, heat resistance, and resistance after heating the containers are also possible. It is possible to provide a laminate suitable for a food container that can be used in a microwave oven and an oven having both impact properties and printability.

The present invention is described in detail below.
The long-fiber non-woven fabric used in the present invention is a non-woven fabric composed of continuous fibers obtained by a spunbond or melt blow method, and an average stress at 5% elongation of 0.01 to 60 N per basis weight (g / m ² ). / 5cm. The elongation is 20% or more. If the average stress at 5% elongation exceeds 60 N / 5 cm, the moldability is poor and the non-woven fabric sheet floats during molding. If it is less than 0.01 N, the sheet strength is too weak and the sheet breaks during molding. Preferably it is 0.1-50N / 5cm, More preferably, it is 0.1-30N / 5cm.
The average stress at 5% elongation in the present invention refers to the tension applied when stretching 5% at a width of 5 cm in accordance with JIS L1906 5.3.1 using a tensile tester in the vertical and horizontal directions of the nonwoven fabric. It is a value obtained by measuring each in the direction n = 5 and obtaining a value (N) of (vertical + horizontal) / 2.
The value obtained by further dividing this value by the basis weight (g / m ² ) of the sample is preferably 1.0 N / 5 cm or less, more preferably 0.2 to 0 per basis weight (g / m ² ). .8 N / 5 cm.

  Moreover, the average breaking elongation of the long-fiber nonwoven fabric is a value obtained as (vertical + horizontal) / 2 with respect to the breaking elongation (%) in the vertical and horizontal directions, and the average breaking elongation is 10% or more. , Preferably 20 to 100%. When the average breaking elongation of the long-fiber nonwoven fabric is less than 10%, the mold followability at the time of container molding may be inferior.

The basis weight of the long fiber nonwoven fabric is 20 to 180 g / m ² , and the thickness is 0.16 mm or more. Basis weight becomes poor moldability exceeds 180 g / m ^2, may sometimes out lifting at the time of molding. When it is less than 20 g / m ² , the heat insulating property is small, and when it is taken out after the range treatment, it is too hot and the handling property is deteriorated. Preferably it is 20-100 g / m < ² >, More preferably, it is 30-60 g / m < ² >.
If the thickness of the long-fiber nonwoven fabric is less than 0.16 mm, the heat insulating properties are deteriorated, and the heat is excessive and the handling properties are deteriorated. Preferably it is 0.2 mm or more, More preferably, it is 0.3 mm or more.

The form of bonding of the fibers constituting the long-fiber nonwoven fabric of the present invention is not particularly limited, but embossing is appropriate in terms of preventing fuzz and handling. The embossing is preferably dot processing, and in particular, when surface smoothness is required, plain processing is also possible. In particular, when a high degree of heat insulation is required and a thick and bulky material is required, needle punching and the following extrusion laminate can be used in combination.
In the embossing process, the embossed area ratio is preferably 10% or more, more preferably 20% or more, and further preferably 25% or more. When the embossed area ratio is less than 10%, fuzz on the non-woven fabric surface after molding tends to increase, and the handling property tends to deteriorate.

  Synthetic resins such as polyolefin, polyamide, polyester, etc. are mentioned as the material of the long-fiber nonwoven fabric, and it is preferable that it is similar to the material of the sheet, but heat resistance, diversity that can adopt various configurations according to the purpose, recycling Polyester is more preferable from the viewpoint of properties.

  As polyester which comprises a long-fiber nonwoven fabric, the aromatic polyester which has aromatic rings, such as a benzene ring and a naphthalene ring, as a main component is preferable. For example, software such as polytrimethylene terephthalate (hereinafter also referred to as PTT), polybutylene terephthalate (hereinafter also referred to as PBT), polybutylene naphthalene dicarboxylate (hereinafter also referred to as PBN), polytetramethylene oxide glycol (hereinafter referred to as PTMG), etc. Segment-containing polybutylene terephthalate (hereinafter also referred to as soft PBT), polyethylene terephthalate (hereinafter also referred to as soft PET), polybutylene naphthalene dicarboxylate (hereinafter also referred to as soft PBN) and polytrimethylene naphthalate (hereinafter also referred to as soft PTN) ) And aromatic copolyesters described later.

The aromatic copolymer polyester in the present invention is a polyester obtained by copolymerizing the above-exemplified aromatic polyester with another third component as a dicarboxylic acid or / and glycol component.
Dicarboxylic acids that can be copolymerized in addition to the main aromatic acid component include terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, hydroxybenzoic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid. Examples thereof include aromatic dicarboxylic acids such as acid, 3,5-dicarboxybenzenesulfonic acid, and 5-sodiumsulfoisophthalic acid. Examples of the alicyclic dicarboxylic acid include hexahydroterephthalic acid, hexahydroisophthalic acid, and tetrahydrophthalic anhydride. Examples of the aliphatic dicarboxylic acid include succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, and hydrogenated dimer acid. These are used within a range that does not significantly reduce the melting point and crystallinity of the resin, and the amount thereof is less than 20 mol%, preferably less than 10 mol% of the total acid component.
Of these, isophthalic acid, adipic acid, sebacic acid and glutaric acid are preferred.

As the glycol component that can be copolymerized in addition to the main glycol component, an alkylene glycol having 1 to 25 carbon atoms can be used. For example, diethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,3-butanediol, 2-methyl 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1, 6-hexanediol, 1,9-nonanediol, neopentyl glycol, dimethylol heptane, dimethylol pentane, tricyclodecane dimethanol, ethylene oxide derivatives of bisphenol X (X is A, S, F) and the like. These glycols are used in an appropriate combination depending on the balance of various properties, but since the premise is that the crystallinity of the main ester unit in the polymer is not hindered, the amount of copolymerization thereof is 20 mol% of the total glycol component. The following is desirable.
Of these, diethylene glycol, neopentyl glycol, and butanediol / ethylene glycol are preferred.

The melting point (hereinafter abbreviated as Tm ₂ ) of the aromatic copolymer polyester used in the present invention is preferably 150 ° C. to (Tm ₁ -20 ° C.). The Tm ₂ is less than 0.99 ° C., heat resistance tends to poor when formed into a nonwoven fabric tends to hardly improved exceeds (Tm ₁ -20 ℃), adhesion between the fibers. Particularly preferably from _{155 ℃ ~ (Tm 1 -30 ℃} ), more preferably from _{160 ℃ ~ (Tm 1 -40 ℃} ).

The continuous fiber constituting the long-fiber nonwoven fabric may be the above aromatic polyester alone, but it is preferable to combine the aromatic polyester and the above aromatic copolymerized polyester. As a combination method, a composite spinning fiber such as a core / sheath fiber having a low melting point component and a core having a high melting point component, or a side-by-side fiber having a low melting point component and a high melting point component, an aromatic polyester and an aromatic fiber are used. Examples thereof include a method of blend spinning with polymerized polyester and a method of blending low melting point heat-adhesive fibers with high melting point fibers.
Examples of such combinations include polyethylene terephthalate (hereinafter PET) / PBT, PET / soft PBT, PET / copolymerized PET (hereinafter CO-PET), PET / soft PET, PET / PEL, PBT / CO-PET, PBT. / Soft PET, PBT / Soft PBT, etc.
The core / sheath fiber may be produced by a general composite spinning method, but more preferably a fiber obtained by blend spinning spinning of a high melting point polymer and a low melting point polymer. According to this method, the operability is good, and the moldability and foldability can be improved without significantly increasing the cost. Specifically, it is a blend of PET / PBT, PET / PEL, PET / soft PBT, PET / soft PET, PBT / soft PBT, PBT / CO-PET, PBT / soft PET, and the like.

  In the case of blending, the blend ratio (high melting point polymer / low melting point polymer) is preferably 70/30 to 99/1 by mass ratio, more preferably 80/20 to 99/1, and still more preferably 90. / 10 to 99/1. If the proportion of the low melting point component is too large, drip may occur during spinning, which may cause problems in operability.

In the blending method of the present invention, the effect of including the aromatic copolymer polyester having the melting point Tm _{2 in} the aromatic polyester having the melting point Tm ₁ is considered as follows.
That is, the melted blend passes through the spinning orifice with the aromatic copolyester well dispersed in the matrix of the aromatic polyester, but at the molten contact interface before spinning, the aromatic copolyester. The copolymerization of the polymerized polyester and the aromatic polyester proceeds, and when the addition amount is small, the copolymerization is completed in a relatively short time and dispersed in the matrix. Next, when a large shearing force is applied to the spinning orifice, it is presumed that the copolymer having a low melt viscosity is ejected to the wall surface of the orifice to form a seascore (core-sheath) structure.

  For this reason, aromatic polyesters and aromatic copolyesters are resin blends (two or more polymers are added as resins, mixed in an extruder, melt extruded, and spun). Alternatively, the aromatic copolymer polyester and the aromatic polyester may be copolymerized in advance by kneading or the like before the resin is charged.

  The fiber thus spun is taken up in the form of a web on the net while cooling to the vicinity of the solidification point. At this time, the fiber containing the aromatic copolymer polyester has a high bonding force at the interface between the fibers in contact. Then, even if embossing or the like is performed, the strength of the nonwoven fabric is greatly improved. From this result, it is conceivable that a seascore structure is formed and an effect similar to that of a heat-bonding fiber is expressed.

  At this time, the melting point and the flow start temperature, which are average characteristics of the resin constituting the fiber, are only slightly lowered. In other words, it exhibits a behavior that does not substantially impair the characteristics of the aromatic polyester as the main component. Content of the aromatic copolyester which can express such an effect is 1 to 15 weight%. If it is less than 1%, almost no effect is observed. If the content exceeds 15% by mass, the characteristics of the aromatic polyester as the main component may be slightly deteriorated.

  Although the fineness of the single fiber which comprises the long-fiber nonwoven fabric of this invention is not specifically limited, Preferably it is 15 dtex or less, More preferably, it is 1-8 dtex.

Moreover, it is preferable that the single side | surface of the long-fiber nonwoven fabric in this invention is given to the whole surface surface using the printing machine in any one of gravure printing, flexographic printing, and offset. The ink used for the printing process is preferably a polyester resin or polyurethane resin as a binder from the viewpoint of adhesion to the nonwoven fabric.
The thickness of the printing process is preferably 20 μm or more, more preferably 30 μm or more over the entire surface. In a printing process of less than 20 μm, fuzz on the nonwoven fabric surface after molding increases, and handling properties may deteriorate.

  Instead of printing, the film may be extruded and laminated using a T-die film extruder or the like. The film is preferably a polypropylene film, PBT or PTT film, more preferably a PBT or PTT film. The thickness of the extruded laminate film is preferably about 10 to 100 μm. Extrusion laminating may be performed not only on one side of the long-fiber nonwoven fabric but also on both sides.

Furthermore, it is preferable that the long-fiber non-woven fabric in the present invention is laminated on a polyester resin such as PBT or PTT using a T-die film extruder or the like on the side opposite to the printed surface. By this, the adhesiveness of a nonwoven fabric and the synthetic resin sheet mentioned later improves, and also heat insulation improves. The thickness of the extruded laminate film is preferably about 10 to 100 μm.
Such a printed surface or laminated film surface is the outermost layer in the container-molded laminate of the present invention, and by having these layers, an effect of excellent fuzz resistance, handling properties, and printability is obtained. It is done.

  Next, the long-fiber non-woven fabric subjected to the above-described processing in the present invention is laminated with a synthetic resin sheet capable of container molding by the following thermoforming. The laminating method can employ a known bonding method, and is not particularly limited, such as an adhesive application method, an adhesive spraying method, an adhesive film laminating method, but the melting point and softening point of the adhesive used for laminating is 90 ° C. or higher. It is preferable that When the melting point is less than 90 ° C., there is a tendency that floating occurs easily after the range treatment. More preferably, it is 130 degreeC or more, More preferably, it is 180 degreeC or more.

  The synthetic resin sheet that can be molded by thermoforming in the present invention is a sheet that can be used for molding containers such as trays and cups using a known method, and is usually produced without stretching by a melt extrusion method. It is a sheet having a thickness of about 100 μm to 1 mm. Moreover, when laminated with a long-fiber nonwoven fabric and formed into a container, the inner wall surface of the container is formed.

Synthetic resins forming the sheet include general-purpose synthetic resins such as polyolefins, polyamides, and polyesters. Polyesters are used from the viewpoints of heat resistance, diversity that can adopt various configurations according to purposes, and recyclability. preferable.
When the synthetic resin sheet in the present invention is a polyester-based sheet and adheres to the long fiber nonwoven fabric in the present invention, it is preferable to use a polyester-based adhesive (agent) in terms of recyclability and adhesiveness.

  Examples of the polyester resin used for the polyester sheet in the present invention include PET, PTT, PBT, polycyclohexylene dimethylene terephthalate, polyethylene naphthalene dicarboxylate, polypropylene naphthalene dicarboxylate, polybutylene naphthalene dicarboxylate, and liquid crystallinity. Although it is polyester, PET is particularly preferable.

  The polyester resin used in the polyester sheet of the present invention has an intrinsic viscosity of 0.70 dL / g or more, preferably 0.80 dL / g or more. When the intrinsic viscosity is less than 0.70 dL / g, the obtained sheet and the molded body thereof are inferior in mechanical strength, and operation failure due to sheet sagging tends to occur in the sheet preheating process at the time of molding the molded body. is there.

  As a polyester-type resin in this invention, you may use aromatic dicarboxylic acid other than the main acid component, alicyclic dicarboxylic acid, and aliphatic dicarboxylic acid as some acid components. Aromatic dicarboxylic acids include terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, hydroxybenzoic acid, diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid, diphenoxy Examples include ethanedicarboxylic acid, 3,5-dicarboxybenzenesulfonic acid, and 5-sodium sulfoisophthalic acid. Examples of the alicyclic dicarboxylic acid include cyclohexane dicarboxylic acid and tetrahydrophthalic anhydride. Examples of the aliphatic dicarboxylic acid include succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, and hydrogenated dimer acid. These are used within a range that does not significantly reduce the melting point and crystallinity of the resin, and the amount thereof is less than 20 mol%, preferably less than 10 mol% of the total acid component.

  Moreover, the polyester-type resin in this invention can use another kind of glycol, ie, C1-C25 alkylene glycol, as a part of the glycol component. For example, diethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,3-butanediol, 2-methyl 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1, 6-hexanediol, 1,9-nonanediol, neopentyl glycol, dimethylol heptane, dimethylol pentane, tricyclodecane dimethanol, ethylene oxide derivatives of bisphenol X (X is A, S, F) and the like. These glycols are used in an appropriate combination depending on the balance of various properties, but since the premise is that the crystallinity of the main ester unit in the polymer is not hindered, the amount of copolymerization thereof is 20 mol% of the total glycol component. The following is desirable.

  Furthermore, the polyester resin in the present invention can contain a tri- or higher functional polycarboxylic acid or polyol component only in a small amount. For example, trimellitic anhydride, benzophenone tetracarboxylic acid, trimethylolpropane, glycerin, pyromellitic anhydride, pentaerythritol, 5-hydroxyisophthalic acid and the like can be used at 3 mol% or less.

  Furthermore, the polyester resin in the present invention can contain a bifunctional polyether component only in a small amount. For example, PTMG, ethylene oxide modified PTMG and the like can be used in an amount of 10% by mass or less. Moreover, 10 mass% or less can also be used for compounds such as p-phenylphenol, benzyloxybenzoic acid, naphthalene monocarboxylic acid, and polyethylene glycol monomethylene ether.

  In order to improve the impact resistance, heat resistance, moldability and the like of the sheet, the polyester-based sheet in the present invention can contain other types of resins. Other types of resins that can be included are those that do not show significant thermal decomposition during polyester sheet molding or molding, such as polyolefin, polyester, polystyrene, polyamide, silicone, polyacrylic. System resins and elastomers are preferably used.

  It is preferable that the average dispersion diameter in the sheet | seat of the said other kind resin is 10 micrometers or less. When the dispersion diameter is larger than 10 μm, the molded article made of the obtained sheet may not have impact resistance.

  The resin contained in the polyester sheet in the present invention is preferably a resin having a temperature at which the loss tangent shows a maximum value of −20 ° C. or less. Examples thereof include polyolefin resins, polyester elastomers, amorphous polyester resins, styrene elastomers, silicone elastomers, acrylic resins, and composites thereof.

  Examples of the polyolefin-based resin include high-density polyethylene, branched low-density polyethylene, linear low-density polyethylene, ultra-low-density polyethylene, (modified) polypropylene, (anhydrous) maleic acid-modified polyethylene, hydrogenated ethylene butene copolymer, Vinyl acetate-ethylene copolymer, ethyl acrylate-ethylene copolymer, ethylene-propylene copolymer, glycidyl methacrylate-ethylene copolymer, glycidyl methacrylate-ethyl acrylate-ethylene copolymer, ethylene-acrylic acid Examples thereof include metal salts of copolymers, metal salts of ethylene-methacrylic acid copolymers, and modifications thereof. These may be used alone or in combination of two or more. Preferred are linear low density polyethylene, ultra-low density polyethylene, maleic acid-modified polyethylene, hydrogenated ethylene butene copolymer, ethyl acrylate-ethylene copolymer, glycidyl methacrylate-ethyl acrylate-ethylene copolymer.

  Examples of the polyester elastomer include polybutylene terephthalate (hereinafter referred to as PBT) and polyalkylene glycol (for example, polyoxytetramethylene glycol), PBT and aliphatic polyester (for example, polycaprolactone, polybutylene adipate). Examples thereof include, but are not limited to, those made of PET and polyalkylene glycol, and those made of PET and aliphatic polyester.

  The above-mentioned amorphous polyester resin is selected from the above-mentioned acid component and glycol component. In particular, the main acid component is terephthalic acid, isophthalic acid, phthalic acid, sebacic acid, adipic acid, dimer acid or a mixture thereof, and the main glycol component is ethylene glycol, trimethylene glycol, butanediol, neopentyl. Any of glycol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, diethylene glycol, dimer diol and mixtures thereof are preferably used.

  Examples of the styrene-based elastomer include styrene ethylene copolymer, styrene ethylene butene copolymer, hydrogenated styrene ethylene butene copolymer, styrene butadiene copolymer, hydrogenated styrene butadiene copolymer, and the like. Examples of these acid and epoxy modifications are given.

  Examples of the acrylic resin include polymethyl acrylate, polyethyl acrylate, polybutyl acrylate, and the like and copolymers thereof. Furthermore, examples of the composite of these resins include a core / shell type rubber made of silicone-acrylic resin, and a core / shell type rubber made of polyolefin-acrylic resin.

  The addition amount of the above-mentioned other types of resins is 1 to 10% by mass, preferably 3 to 7% by mass with respect to the mass of the sheet. If the amount is less than 1% by mass, the impact resistance improving effect is not sufficient. If the amount is more than 10% by mass, adverse effects such as a decrease in heat resistance and a decrease in appearance may occur.

The polyester sheet in the present invention includes any known crystal nucleating agent, for example, inorganic nucleating agents such as talc, kaolin, and silica, and organic materials such as PBT oligomers, sodium benzoate, sodium stearate, and high polymerization degree PET pulverized products. Nucleating agents can be added. The addition amount of the crystal nucleating agent is 5% by mass or less, and is appropriately set according to the kind of the nucleating agent. The addition amount of the crystal nucleating agent is 0.001% by mass or more, preferably 0.01% by mass, most preferably 0.05% by mass or more. If it is less than 0.001% by mass, good crystallinity cannot be obtained. , Productivity and heat resistance tend to decrease. The addition amount of the crystal nucleating agent is preferably 10% by mass or less, more preferably 8% by mass or less, and most preferably 5% by mass or less. If the amount exceeds 10% by mass, the heat-resistant deformability and impact resistance tend to decrease. is there.
A polyester sheet known as a C-PET sheet containing polyethylene terephthalate as a main component and a small amount of a crystal nucleating agent (for example, C-PET sheets manufactured by Toyobo Co., Ltd .: trade names PETMAX C560, C580, etc.) Can also be suitably used.

  Furthermore, various polymers or additives can be blended depending on the purpose. Examples of the polymer include polyamide polymers, polyacrylic polymers, polycarbonate resins, and silicone resins. Additives include known hindered phenol, sulfur, phosphorus and amine antioxidants, hindered amine, triazole, benzophenone, benzoate, nickel, salicyl and other light stabilizers, antistatic Agents, lubricants, molecular modifiers such as peroxides, epoxy compounds, isocyanate compounds, compounds having reactive groups such as carbodiimide compounds, metal deactivators, organic and inorganic nucleating agents, neutralizing agents, control agents Acid agents, antibacterial agents, fluorescent whitening agents, fillers, flame retardants, flame retardant aids, organic and inorganic pigments, dyes, and the like can be added.

  The polyester-based sheet used in the laminate of the present invention may be composed of not only a single layer but also two or more layers. Layers having different compositions as described in this specification, or PET containing nucleating agent, isophthalic acid copolymerized PET, amorphous polyester resin copolymerized with 1,4-cyclohexanedimethanol, polyethylene naphthalate resin An example of a multi-layered layer is given.

  The laminated body for container molding of the present invention can mold containers such as trays and cups by a known molding method such as vacuum molding, pressure molding, plug assist molding, match molding, and the like.

EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in full detail, this invention is not limited to this.
First, the synthetic resin sheet used as the food-side contact layer in the container-forming laminate was as described below.
(1) Polyester sheet (C-PET sheet)
PET resin (IV = 1.00 dL / g, manufactured by Toyobo Co., Ltd.) 97 parts by mass of linear low density polyethylene pellets (trade name Novatec LL, Tg <−20 ° C., manufactured by Nippon Polychem Co., Ltd.) 3 Mass parts were mixed and extruded from a T die using a twin-screw kneading extruder (PCM30 manufactured by Ikegai Co., Ltd.) to obtain a 0.5 mm thick sheet. In addition, all the barrel temperatures at the time of sheet forming were 290 degreeC.
(2) Polypropylene sheet (PPF sheet)
50 parts by mass of calcium carbonate powder (manufactured by Dowa Calfine Co., Ltd., average particle size 1.4 μm) is mixed with 50 parts by mass of polypropylene pellets (manufactured by Tokuyama Co., Ltd., Tokuyama Polypro P130G MI = 4 g / 10 min). A 0.5 mm thick sheet was obtained by extruding from a T-die using a shaft kneading extruder (PCM30 manufactured by Ikegai Co., Ltd.). In addition, all the barrel temperatures at the time of sheet forming were 250 degreeC.

  Next, production of a nonwoven fabric to be a heat insulating layer in a container molding laminate and production of a container molding laminate by joining the nonwoven fabric and the synthetic resin sheet will be described.

Example 1
100 parts of terephthalic acid (hereinafter abbreviated as TPA), 40 parts of ethylene glycol (hereinafter abbreviated as EG) and 15 parts of neopentyl glycol (hereinafter abbreviated as NPG) were charged with a small amount of catalyst, and transesterification and polymerization were conducted in a conventional manner. Thereafter, it was pelletized to obtain an aromatic copolymer polyester (hereinafter abbreviated as COPES) having a melting point of 178 ° C. and an intrinsic viscosity of 0.780.
Polybutylene terephthalate having a melting point of 230 ° C. and an intrinsic viscosity of 1.205, charged with 100 parts of TPA and 70 parts of 1,4-butanediol (hereinafter abbreviated as BG) with a small amount of catalyst, transesterified by a conventional method, and pelletized after polymerization. (Hereinafter abbreviated as PBT).
10 parts of COPES obtained above and 90 parts of PBT were put into a rotary vacuum dryer, mixed and dried (dried to a moisture content of 0.002% by mass), and subjected to spinning. Spinning at a spinning temperature of 260 ° C. from a nozzle with an orifice diameter of 0.23 mm, spinning at a single hole discharge rate of 0.7 g / min, and cooling air at 20 ° C. from 50 mm below the nozzle at a wind speed of 0.5 m / sec. The fiber bundle is pulled to the take-up net surface moving at a speed of 50 m / min at a point 1.5 m below the nozzle with an ejector installed at a point 0.8 m below the nozzle while sucking at a yarn speed of 4100 m / min. The film was sprinkled and laminated while the fiber was opened. The nonwoven web laminated on the net surface is embossed at 210 ° C with an embossing roller with a linear pressure of 50 kN / m, an embossed area ratio of 22% (dot pattern), a basis weight of 40 g / m ² , and a thickness of 0.25 mm A fiber nonwoven fabric was obtained.
Furthermore, PBT 20 μm extrusion lamination was performed on one side of the non-woven fabric using a T-die film extruder to obtain a PBT film-laminated non-woven fabric serving as a heat insulating layer in the laminate for forming a container of the present invention.

Next, a polyester resin (trade name: Byron 500, manufactured by Toyobo Co., Ltd.) using ethyl acetate as a solvent for the PBT surface of the obtained PBT film-laminated nonwoven fabric and the C-PET sheet (sheet for the inner wall surface of the container). Adhesive processing was carried out by a solvent dry lamination method using as a bonding agent to obtain a laminate for container molding of the present invention. The amount of polyester resin applied was adjusted to 30 g / m ² .
Table 1 shows the configuration and evaluation results of the obtained container-forming laminate.
(Example 2)
A long fiber nonwoven fabric having a basis weight of 40 g / m ² was obtained in the same manner as in Example 1 except that the embossed area ratio was 11%.
Next, on the one side of the obtained long fiber nonwoven fabric, a printing process with a thickness of 30 μm is performed using an ink having a polyester resin (trade name: Byron 200, manufactured by Toyobo Co., Ltd.) as a binder using a gravure printing machine. A long fiber nonwoven fabric was obtained.
Furthermore, the PBT film laminated nonwoven fabric was obtained by carrying out a PBT 20 μm laminating process on the printed nonwoven fabric using a T-die film extruder on the side opposite to the printed surface.
Subsequently, the PBT surface of the obtained PBT film-laminated nonwoven fabric and the PPF sheet (sheet for the inner wall surface of the container) were bonded in the same manner as in Example 1 to obtain a container molding laminate of Example 2. It was. Table 1 shows the configuration and evaluation results of the obtained container-forming laminate.
(Example 3)
Using PPF sheet instead of C-PET, using the same embossed spunbond nonwoven fabric as in Example 2, and carrying out PBT 20 μm laminating on both sides of the embossed spunbond nonwoven fabric as in Example 1. The container-molding laminate of Example 3 was obtained. Table 1 shows the configuration and evaluation results of the obtained container-forming laminate.
Example 4
A container-molded laminate of Example 4 was obtained in the same manner as Example 3 except that the PPF sheet was C-PET. Table 1 shows the configuration and evaluation results of the obtained container-forming laminate.
(Example 5)
100 parts of TPA and 60 parts of trimethylene glycol (hereinafter abbreviated as TG) are charged with a small amount of catalyst, transesterified by a conventional method, polymerized and pelletized, polytrimethylene terephthalate having a melting point of 221 ° C. and an intrinsic viscosity of 1.310 ( PTT) was obtained.
After 90 parts of the obtained PTT and 10 parts of the COPES obtained above were dried, spinning was performed at a spinning temperature of 255 ° C. from a slit hole nozzle at a single hole discharge rate of 0.25 g / min. The air is cooled at a wind speed of 0.5 m / sec, and is drawn while being sucked at a thread speed of 4000 m / min with an ejector installed at a point of 0.8 m below the nozzle. The fiber bundle was spun off and laminated on the surface of the take-up net moving at a speed of / min. The web laminated on the net surface has a basis weight of 50 g / m ² and a thickness of 0.31 mm which is processed by partial thermocompression bonding with an embossing roll at 230 ° C. with a linear pressure of 50 kN / m to an emboss area ratio of 22% (dot pattern) The long fiber nonwoven fabric was obtained.
On one side of the long fiber nonwoven fabric, a PTT film laminate long fiber nonwoven fabric was obtained by carrying out a PTT 20 μm lamination using a T-die film extruder.
Next, the PTT surface of the obtained PTT film-laminated long-fiber nonwoven fabric and the C-PET were mixed with a solvent dry laminate using a polyester resin (trade name: Byron 500, manufactured by Toyobo Co., Ltd.) using ethyl acetate as a solvent. Adhesion processing was performed by the method to obtain a container-forming laminate of Example 5. Table 1 shows the configuration and evaluation results of the obtained container-forming laminate.
(Example 6)
A long-fiber nonwoven fabric having a basis weight of 50 g / m ² was obtained in the same manner as in Example 5 except that the embossed area ratio was 11%.
Next, the entire surface of the obtained long fiber nonwoven fabric was subjected to a printing process with a thickness of 30 μm in the same manner as in Example 2 to obtain a printed long fiber nonwoven fabric.
Further, a PTT film laminated nonwoven fabric was obtained by performing a PTT 20 μm laminating process on the printed nonwoven fabric using a T-die film extruder on the side opposite to the printed surface.
Next, the PTT surface of the obtained PTT film-laminated nonwoven fabric and the PPF sheet were bonded in the same manner as in Example 5 to obtain a container-forming laminate of Example 6. Table 1 shows the configuration and evaluation results of the obtained container-forming laminate.
(Example 7)
A PPF sheet was used in place of C-PET, the same embossed spunbond nonwoven fabric as in Example 6 was used, and PTT 20 μm was laminated on both sides of the embossed spunbond nonwoven fabric in the same manner as in Example 5. A container-molding laminate of Example 7 was obtained. Table 1 shows the configuration and evaluation results of the obtained container-forming laminate.
(Example 8)
A container-molded laminate of Example 8 was obtained in the same manner as Example 7 except that the PPF sheet was C-PET. Table 1 shows the configuration and evaluation results of the obtained container-forming laminate.
Example 9
Polyethylene terephthalate (hereinafter referred to as PET) becomes the core, COPES obtained above becomes the sheath, and the volume ratio becomes 5: 5. Partial fiber thermocompression bonding was performed at a linear pressure of 50 kN / m to obtain a long-fiber nonwoven fabric having a basis weight of 40 g / m ² processed to an emboss area ratio of 22%.
On one side of the long-fiber non-woven fabric, a PBT 20 μm laminate process was performed using a T-die film extruder to obtain a PBT film-laminated non-woven fabric serving as a heat insulating layer in the laminate for container molding of the present invention.
Subsequently, the PBT surface of the obtained PBT film laminate nonwoven fabric and the C-PET sheet were bonded in the same manner as in Example 1 to obtain a container-molding laminate of the present invention. The amount of polyester resin applied was adjusted to 30 g / m ² .
The constitution and evaluation results of the obtained container-forming laminate are shown in Table 2.
(Example 10)
A long fiber nonwoven fabric having a basis weight of 40 g / m ² was obtained in the same manner as in Example 9 except that the embossed area ratio was 11%.
Next, the entire surface of the obtained long fiber nonwoven fabric was subjected to a printing process with a thickness of 30 μm in the same manner as in Example 2 to obtain a printed long fiber nonwoven fabric.
Furthermore, the PBT film laminated nonwoven fabric was obtained by carrying out a PBT 20 μm laminating process on the printed nonwoven fabric using a T-die film extruder on the side opposite to the printed surface.
Subsequently, the PBT surface of the obtained PBT film-laminated nonwoven fabric and the PPF sheet were bonded in the same manner as in Example 1 to obtain a container-forming laminate of Example 10. The constitution and evaluation results of the obtained container-forming laminate are shown in Table 2.
(Example 11)
A PPF sheet was used instead of C-PET, the same embossed spunbond nonwoven fabric as in Example 10 was used, and a laminate process of PBT 20 μm was further performed on both sides of the embossed spunbond nonwoven fabric. The laminated body for container molding of Example 11 was obtained. The constitution and evaluation results of the obtained container-forming laminate are shown in Table 2.
(Example 12)
A container-molded laminate of Example 12 was obtained in the same manner as Example 11 except that the PPF sheet was C-PET. The constitution and evaluation results of the obtained container-forming laminate are shown in Table 2.
(Example 13)
The same embossed spunbonded nonwoven fabric as in Example 1 was obtained, and a copolymerized polyester (manufactured by Toyobo Co., Ltd., trade name: Byron GM913, melting point 126 ° C.) was applied to one side of the nonwoven fabric in the same manner as in Example 1 to a thickness of 20 μm. Then, the laminated laminate of the embossed spunbond nonwoven fabric and C-PET was obtained. The constitution and evaluation results of the obtained container-forming laminate are shown in Table 2.
In addition, although the laminated body for container shaping | molding of Example 13 had the advantage that manufacturing cost was the cheapest, the somewhat difficult point was recognized by the point of printability.

(Comparative Example 1)
Using PET with an intrinsic viscosity of 0.68, spinning at a spinning temperature of 285 ° C., with a hole diameter of 0.35 mm, a single hole discharge rate of 2.5 g / min, and a take-up speed of 4800 m / min, and embossing at intervals of 5 mm A long-fiber non-woven fabric was obtained in the same manner as in Example 1 except that the embossed area ratio was 11% and the temperature was 240 ° C. and the linear pressure was 50 kN / m.
Next, on one side of the obtained long fiber nonwoven fabric, a linear low density polyethylene (made by Nippon Polychem Co., Ltd., trade name Novatec) was used instead of PBT using a T-die film extruder in the same manner as in Example 1. LL) and a lamination process of polyethylene (PE) 20 μm was performed.
A PPF sheet (food contact layer sheet) was obtained in the same manner as in Example 1 except that polyurethane resin (trade name: Byron UR-1350, manufactured by Toyobo Co., Ltd.) was used as an adhesive for the obtained PE laminated long fiber nonwoven fabric. Adhesion processing was carried out to obtain a container-forming laminate of Comparative Example 1. The constitution and evaluation results of the obtained container-forming laminate are shown in Table 2.
(Comparative Example 2)
Instead of the polyester (PBT + COPES) of Example 1, polypropylene (made by Tokuyama Co., Ltd., Tokuyama Polypro P130G) was used to form a PP spunbond nonwoven web, and an embossing roller with an embossing roll at 190 ° C. and a linear pressure of 50 kN / m. A PP long-fiber nonwoven fabric having a basis weight of 40 g / m ² processed to an embossed area ratio of 11% was obtained.
To the obtained PP long fiber nonwoven fabric, a modified polyolefin resin (Bondyne TX8030 manufactured by Sumika Atchem Co., Ltd.) was used as an adhesive, and a PPF sheet (thickness: 500 μm) was bonded in the same manner as in Example 1. A container forming laminate was obtained. The constitution and evaluation results of the obtained container-forming laminate are shown in Table 2.
(Comparative Example 3)
A PPF sheet (thickness: 500 μm) is bonded to a 50 μm-thick polypropylene film (Sun-Tox Corporation: Sun-Tox-CP) in the same manner as in Example 1 using an ethylene vinyl alcohol adhesive (Kuraray). And the laminated body for container shaping | molding of the comparative example 3 was obtained. The constitution and evaluation results of the obtained container-forming laminate are shown in Table 2.

The main physical property measurement methods employed in the present invention are as follows.
(A) Fabric weight and thickness of nonwoven fabric: measured according to JIS L-1096 method.
(B) Average stress at 5% elongation of nonwoven fabric:
Samples are punched into 5 cm x 20 cm strips in the vertical and horizontal directions, and the tension applied at 5% elongation is measured in the vertical and horizontal directions N = 5 according to JIS L1906 5.3.1 using a Tensilon tensile tester. did.
(C) Polyester IV: Measured at a temperature of 30 ° C. using a mixed solvent of IV: phenol / tetrachloroethane = 60/40 (mass ratio).
(D) Evaluation of laminates-Formability evaluation method:
Using the obtained laminated sheet, a cylindrical molded body having a top opening diameter of 7 cm, a bottom diameter of 7 cm, and a depth of 10 cm at a mold temperature of 170 ° C. using a vacuum pressure forming machine TVP-33 manufactured by Sanwa Kogyo Co., Ltd. Obtained. About the obtained molded object, the float of the nonwoven fabric, tearing, and mold followability were evaluated.
○: Excellent mold followability, no floating or tearing,
Δ: Inferior moldability
X: Floating and tearing are recognized.
・ Heat resistance (handling):
Into the obtained molded body, hot water at 95 ° C. was put until the seventh minute, and the ease of holding the container after one minute was evaluated.
◎: Very good, ○: Good, ×: Poor ・ Heat insulation:
Into the obtained molded body, 95 ° C. hot water was added until the seventh minute, and the outer surface temperature of the container after one minute was measured with a contact-type surface thermometer.
A: Less than 38 ° C., O: 38 ° C. to less than 40 ° C., X: 40 ° C. or more. Abrasion resistance:
The fuzz on the outer surface of the container after the heat rigidity and heat insulation test was observed.
A: No fluff is observed, B: Almost no fluff is observed, X: Many fuzz.
-Impact resistance:
100 g of sand was put into the obtained molded body and dropped on an iron plate from a height of 50 cm under an atmosphere of 0 ° C., and whether or not it cracked was evaluated.
○: No crack, Δ: Lamination of the laminate occurs, ×: Crack occurs.

(Note 1) PES: Polyester resin (Toyobo Co., Ltd .: Byron 500)
Lami (Dry Lami): Adhesive processing by solvent dry lami method
VY Extrusion Lami: Extruded laminate of Byron GM913 (Toyobo Co., Ltd.)
UR: Polyurethane resin (Toyobo Co., Ltd .: Byron UR-1350)
OL: Modified polyolefin resin (manufactured by Sumika Atchem: Bondine TX8030)
EVOH: Ethylene vinyl alcohol adhesive (Kuraray)
(Note 2) CPP: Polypropylene film (manufactured by Sun Tox Corporation: Sun Tox-CP)

  As described above, a laminate in which a long-fiber nonwoven fabric having a specific configuration in the present invention is laminated on a synthetic resin sheet that can be molded by thermoforming has a moldability, heat-resistance rigidity, wear resistance, heat insulation, and impact resistance. It can be understood that both are excellent, and in particular, when a PBT or PTT film is laminated on at least one side of the long-fiber nonwoven fabric, the heat resistance rigidity, wear resistance, heat insulation and the like are further improved.

  The laminate of the present invention can form food containers that can be used in microwave ovens and ovens with good moldability, and the resulting containers have excellent heat insulation, handling properties, heat resistance, impact resistance, printability, and recyclability. Therefore, it can be suitably used for containers in the food field.

Claims (8)

A laminate for container molding in which a long-fiber nonwoven fabric is laminated on a synthetic resin sheet that can be molded by thermoforming, and the long-fiber nonwoven fabric has an average stress of 0.01 to 60 N / 5 cm at 5% elongation, average elongation at break of 20% or more, basis weight 20~180g / m ^2, the container-forming laminated sheet which satisfies the above thickness 0.16 mm.   The laminate for forming a container according to claim 1, wherein an embossed area ratio of the long fiber nonwoven fabric is 10% or more.   The laminate for container molding according to claim 1 or 2, wherein the synthetic resin sheet and the long-fiber nonwoven fabric are mainly composed of aromatic polyester. The long fiber nonwoven fabric is composed of continuous fibers having an aromatic polyester (melting point: Tm ₁ ) and an aromatic copolymer polyester (melting point: Tm ₂ = 150 ° C. to (Tm ₁ -20 ° C.)). The laminate for forming a container according to any one of claims 1 to 3. The ratio of the aromatic polyester (melting point: Tm ₁ ) and the aromatic copolymer polyester (melting point: Tm ₂ = 150 ° C. to (Tm ₁ -20 ° C.)) is 100: 0 to 40:60 (mass ratio). The container-molding laminate according to claim 4, wherein the container-forming laminate is provided.   The laminated body for container molding according to claim 4, wherein the continuous fiber of the long-fiber nonwoven fabric is a core-sheath type composite fiber in which the aromatic polyester is a core and the aromatic copolymer polyester is arranged in a sheath. .   The container according to any one of claims 1 to 6, wherein at least one film selected from polybutylene terephthalate, polytrimethylene terephthalate, and polyester elastomer is laminated on at least one side of the long-fiber nonwoven fabric. Molded laminate.   The laminate for container molding according to claim 1, wherein the surface of the long-fiber nonwoven fabric opposite to the synthetic resin sheet is printed.