JP2022128013A - Resin composition, resin sheet, laminate, package, and method for producing package - Google Patents

Abstract

To provide a resin composition that can achieve a resin sheet having excellent transparency and also having high impact resistance while containing petroleum resin.SOLUTION: A resin composition contains polypropylene having smectic crystals, and petroleum resin.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a resin composition, a resin sheet, a laminate, a package, and a method for manufacturing the package.

Resin packaging bodies are widely used as packaging containers for foods and pharmaceuticals, but in recent years, there is a strong demand for reducing the amount of fossil fuel-derived resins used as an environmental measure. In response to this demand, it is possible to replace all or part of the resin with biomass-derived resin raw materials, but from the viewpoint of reducing carbon dioxide emissions during incineration, it is preferable to reduce the amount of resin itself used.
On the other hand, simply reducing the amount of resin used may reduce the rigidity and make it unusable, so there is a known method of adding petroleum resin to improve rigidity (for example, Patent Document 1. and 2).

Japanese Patent Laid-Open No. 8-157659 JP 2008-87829

However, there is a problem that the sheet obtained by adding petroleum resin is inferior in impact resistance. An object of the present invention is to provide a resin composition capable of realizing a resin sheet having excellent transparency and high impact resistance despite containing a petroleum resin.

As a result of intensive studies, the present inventors have found that the above problems can be solved by combining a polypropylene having smectica crystals with a petroleum resin, and have completed the present invention.
According to the present invention, the following resin composition and the like are provided.
1. A resin composition comprising polypropylene having smectic crystals and a petroleum resin.
2. 2. The resin composition according to 1, wherein the polypropylene has an isotactic pentad fraction of 80 mol % or more and 99 mol % or less.
3. 3. The resin composition according to 1 or 2, wherein the polypropylene has a crystallization rate of 2.5 min ^-1 or less at 130°C.
4. 4. The resin composition according to any one of 1 to 3, wherein the content of the petroleum resin is 1% by mass or more and 20% by mass or less.
5. 5. The resin composition according to any one of 1 to 4, which is substantially free of a nucleating agent.
6. A resin sheet containing the resin composition according to any one of 1 to 5.
7. 7. The resin sheet according to 6, having an internal haze of 15% or less.
8. A laminate comprising the resin sheet according to 6 or 7.
9. 9. The laminate according to 8, wherein a second layer containing polypropylene having smectic crystals is laminated on at least one surface of the resin sheet.
10. 10. The laminate according to 9, wherein the second layer contains a petroleum resin.
11. 9. The laminate according to 8, wherein a second layer containing polypropylene and a nucleating agent is laminated on at least one surface of the resin sheet.
12. 12. The laminate according to any one of 8 to 11, having a thickness of 100 μm or more and 2000 μm or less.
13. A package made using the resin sheet described in 6 or 7 or the laminate described in any one of 8 to 12.
14. A package having at least one layer containing polypropylene having smectic crystals and a petroleum resin,
The isotactic pentad fraction of the polypropylene is 80 mol% or more and 99 mol% or less,
The content of the petroleum resin in the layer is 1% by mass or more and 20% by mass or less,
package.
15. 15. The package according to 13 or 14, which has a buckling strength of 20 N or more measured according to JIS K7181 under the following conditions.
・Measurement sample shape: Flange outer size 125mm x 125mm, flange inner size 104mm x 104mm, top surface outer size: 74mm x 74mm, depth 12mm
- Measurement conditions: Test environment 23°C ± 2°C, 50% RH ± 10% RH, test speed 10 mm/min - Calculation method: Calculate the maximum load at a compressive displacement of 2 mm or less and use it as the buckling strength.
16. A method for producing a package, comprising heat-molding the resin sheet according to 6 or 7 or the laminate according to any one of 8 to 12 at a temperature not higher than the melting point of the polypropylene.

ADVANTAGE OF THE INVENTION According to this invention, the resin composition which has excellent transparency and can realize a resin sheet which has high impact resistance in spite of containing a petroleum resin can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram of an example of the manufacturing apparatus for manufacturing the resin sheet of this invention. 4 is a photograph showing the shape of a measurement sample used for buckling strength evaluation in Examples 2 to 4. FIG. 4 is a photograph of a resin sheet after film impact evaluation (impact resistance test) in Example 2 and Comparative Example 1. FIG. In the figure, Example 2 is shown on the right, and Comparative Example 1 is shown on the left. 1 is a schematic configuration diagram of a manufacturing apparatus used for manufacturing a laminate of Comparative Example 1. FIG.

Hereinafter, the resin composition, resin sheet, laminate, package, and method for manufacturing the package according to the present invention will be described. In this specification, "x to y" represents a numerical range of "x or more and y or less". If there are multiple lower limits such as "x or more" or multiple upper limits such as "y or less" for one technical matter, arbitrarily select and combine the upper and lower limits shall be possible.

1. Resin Composition A resin composition according to an aspect of the present invention includes polypropylene having smectic crystals and a petroleum resin. Smetic crystals are intermediate phases in a metastable state, and each domain size is small, so polypropylene with smectic crystals has excellent transparency. can. Furthermore, in general, adding a petroleum resin to a resin sheet greatly reduces the impact resistance, but the resin composition obtained according to one embodiment of the present invention is excellent in spite of containing a petroleum resin. Has impact resistance. Although the mechanism is not necessarily clear, it is thought to be due to the fine crystal structure derived from smectica crystals. Since the resin sheet obtained from the resin composition according to one aspect of the present invention has excellent impact resistance, it reduces the occurrence of film forming troubles such as breakage during film formation and breakage due to slits that are cut to a predetermined width. Stable film formability can be realized. Further, as described later, by thermoforming the resin sheet, a molded body (packaging body) having high rigidity and excellent transparency can be obtained.
Each component used in the resin composition will be described below.

(polypropylene)
Polypropylene is a polymer containing at least propylene. Specific examples include homopolypropylene, copolymers of propylene and olefins, and the like. In particular, homopolypropylene is preferred because of its heat resistance and hardness.

The polypropylene used in the resin composition according to one aspect of the present invention contains smectic crystals. As described above, smectic crystals are intermediate phases in a metastable state, and are excellent in transparency due to the small size of each domain. In addition, since smectica crystals are in a metastable state, the sheet is softened with a lower amount of heat than α-crystals, which are highly crystallized.
The crystal structure of polypropylene may include other crystal forms such as α-crystal, β-crystal, γ-crystal, and amorphous part, in addition to smectica crystal.
For example, 30% by mass or more, 50% by mass or more, 70% by mass or more, or 90% by mass or more of the polypropylene in the resin sheet may be smectic crystals.
A specific method for confirming the crystal structure is as described in Examples described later.

In one aspect of the present invention, the polypropylene preferably has an isotactic pentad fraction of 80 mol % or more.
If the isotactic pentad fraction is 80 mol % or more, sufficient rigidity can be obtained when made into a resin sheet.
The isotactic pentad fraction of polypropylene is preferably 85 mol% or more, more preferably 90 mol% or more, further preferably 95 mol% or more, and 99 mol% or less. preferably 98.5 mol % or less.
When the isotactic pentad fraction is 80 mol % or more and 99 mol % or less, a resin sheet having excellent rigidity and sufficient transparency can be obtained.
The isotactic pentad fraction is preferably 80 mol% or more and 99 mol% or less, more preferably 85 mol% or more and 99 mol% or less, and 90 mol% or more and 98.5 mol% or less. is more preferable.

The isotactic pentad fraction is the isotactic fraction of a pentad unit (five consecutive isotactic bonds of propylene monomers) in the molecular chain of the resin composition. This fraction can be measured by, for example, the method described in Macromolecules, Vol. 8 (1975), p. 687, and can be measured by ¹³ C-NMR.
A specific method for measuring the isotactic pentad fraction is as described in Examples below.

A copolymer of propylene and an olefin may be a block copolymer or a random copolymer as long as the isotactic pentad fraction is 80 mol % or more (preferably 80 to 99 mol %). or a mixture thereof.
Olefins include ethylene, butylene, cycloolefins, and the like.

In one aspect of the present invention, the melt flow rate (hereinafter sometimes referred to as "MFR") of polypropylene is preferably 0.5 g/10 min or more, more preferably 1 g/10 min or more. , 2 g/10 minutes or more. Further, it is preferably 10 g/10 minutes or less, more preferably 8 g/10 minutes or less, and even more preferably 6 g/10 minutes or less. Within this range, the formability into a film shape or a sheet shape is excellent. The MFR of polypropylene is measured at a temperature of 230° C. and a load of 2.16 kg according to JIS-K7210.

In one aspect of the present invention, the crystallization rate of polypropylene at 130° C. is preferably 2.5 min ⁻¹ or less, more preferably 2.0 min ⁻¹ or less, from the viewpoint of moldability.
When the crystallization speed is 2.5 min ⁻¹ or less, it is possible to prevent deterioration of the design.
Although the lower limit is not particularly limited, it is usually 0.01 min ^-1 or more, preferably 0.05 min ^-1 or more.
A specific method for measuring the crystallization rate is as described in Examples.

In one aspect of the present invention, the resin composition does not substantially contain a nucleating agent, or preferably contains no nucleating agent.
Even when the nucleating agent is included, it is preferably in a small amount, for example, 1.0% by mass or less, 0.5% by mass or less, 0.1% by mass or less, or 0.01% by mass of the resin composition. or less, or 0.001% by mass or less. Moreover, it is 1.0 mass % or less, 0.5 mass % or less, 0.1 mass % or less, 0.01 mass % or less, or 0.001 mass % or less with respect to the amount of polypropylene.
Nucleating agents include, for example, sorbitol-based crystal nucleating agents, and commercially available products include Gelol MD (Shin Nihon Rikagaku Co., Ltd.) and Rikemaster FC-1 (Riken Vitamin Co., Ltd.).

In one embodiment, the crystallization rate of polypropylene is set to 2.5 min ⁻¹ or less without adding a nucleating agent, and the resin composition is formed by cooling at 80 ° C./sec or more to form the above-described smectic crystals. Excellent transparency can be obtained in the resin sheet used.

In order to obtain a resin sheet having an isotactic pentad fraction of 80 mol % or more and 99 mol % or less and a polypropylene crystallization rate of 2.5 min ^-1 or less and having excellent transparency and gloss, smectica crystals are usually used. It is necessary to form
By heating the resin sheet, the polypropylene in the resin sheet transitions to α crystals while maintaining the fine structure derived from smectica crystals, but the polypropylene in the molded product (package) has an isotactic pentad fraction. If the crystallization rate of polypropylene is 85 mol % or more and 99 mol % or less and the crystallization rate of polypropylene is 2.5 min ⁻¹ or less, it can be said to be derived from smectica crystals.

By calculating the scattering intensity distribution and the long period by the small-angle X-ray scattering analysis method, it is possible to judge whether the resin sheet is obtained by cooling at 80° C./sec or more or not. That is, it is possible to judge whether or not the resin sheet has a fine structure derived from smectic crystals by the above analysis. Measurement is performed under the following conditions.
・An ultraX 18HF (manufactured by Rigaku Corporation) is used as an X-ray generator, and an imaging plate is used to detect scattering.
・Light source wavelength: 0.154 nm
・Voltage/current: 50kV/250mA
・Irradiation time: 60 minutes ・Camera length: 1.085m
・Sample thickness: Sheets are stacked so that the thickness is 1.5 to 2.0 mm. The sheets are stacked so that the film-forming (MD) direction is aligned.
In order to shorten the measurement time, the sheets are overlapped so as to have a thickness of 1.5 to 2.0 mm.

In one aspect of the present invention, the polypropylene is preferably 1 J / g or more, preferably 1.5 J / g or more on the low temperature side of the maximum endothermic peak in a curve (DSC curve) obtained by differential scanning calorimetry (DSC) measurement. It has an exothermic peak (also referred to as a “low temperature side exothermic peak”). Although the upper limit is not particularly limited, it is usually 10 J/g or less.

In one aspect of the present invention, the content of polypropylene in the resin composition is usually 75% by mass or more, preferably 80% by mass or more, and more preferably 87% by mass or more. Moreover, it is usually 99% by mass or less, preferably 95% by mass or less.

(petroleum resin)
Petroleum resins include, for example, dicyclopentadiene-based resins obtained by thermally polymerizing a cyclopentadiene fraction; aromatic (C9-based) petroleum resins obtained by cationic polymerization of a mixture of aromatic olefins having 9 carbon atoms; chain-like resins having 5 carbon atoms Aliphatic (C5) petroleum resin obtained by cationic polymerization of a mixture of olefins; styrene resin; alkylphenol resin; and xylene resin.
Further, a copolymer of at least two of the monomers of each of the above resins; the petroleum resin or a petroleum resin obtained by acid-modifying the copolymer; A mixture or the like in which at least two of the above components are mixed can be mentioned.

From the viewpoint of transparency and moldability, the petroleum resin is preferably a copolymer petroleum resin containing an aromatic component, more preferably a copolymer petroleum resin of an aromatic component and dicyclopentadiene.

The softening point of the petroleum resin is preferably 50 to 170°C, more preferably 100 to 160°C. When the softening point is less than 50°C, the heat resistance tends to decrease, and the resin component tends to bleed out to the surface in a high-temperature atmosphere. It tends to be difficult to impart the effect of softening the sheet in the molding temperature range where the body does not whiten, and there is a concern that the transparency may deteriorate. A softening point is measured by the method based on JISK2207.

More preferably, the petroleum resin has a number average molecular weight of 600 or more and 1,000 or less. If the number average molecular weight is less than 600, the heat resistance tends to decrease and the resin component tends to bleed out to the surface in a high temperature atmosphere. There is a concern that the effect of softening the sheet in the molding temperature range in which the molded body does not whiten is difficult to impart, resulting in poor transparency. The number average molecular weight of the petroleum resin is more preferably 650 or more, particularly preferably 700 or more.
A number average molecular weight is a value of polystyrene conversion measured by a gel permeation chromatography (GPC).

In one aspect of the present invention, the content of the petroleum resin in the resin composition is usually 1% by mass or more, preferably 3% by mass or more, and more preferably 5% by mass or more. Moreover, it is usually 20% by mass or less, preferably 15% by mass or less, and more preferably 12% by mass or less.

(other ingredients)
In addition to the polypropylene and petroleum resin described above, other resin components or additives may be added to the resin composition according to one aspect of the present invention.
Other resin components include polypropylene other than the above-mentioned polypropylene, polyethylene, and the like. In addition, in consideration of environmental friendliness, biomass-derived resin raw materials (for example, bio-polypropylene, bio-polyethylene, etc.) may be added.
Among polyethylenes, linear low-density polyethylene (LLDPE) is expected to have the effect of further increasing transparency, and bio-polyethylene is also environmentally friendly.

The resin composition according to one aspect of the present invention preferably does not substantially contain inorganic compounds such as inorganic fillers or does not contain inorganic compounds. Inclusion of such components may impede transparency.
Even if it contains an inorganic compound such as an inorganic filler, it is preferably in a small amount. 01% by mass or less, or 0.001% by mass or less. Moreover, it is 1.0 mass % or less, 0.5 mass % or less, 0.1 mass % or less, 0.01 mass % or less, or 0.001 mass % or less with respect to the amount of polypropylene.

In one aspect of the present invention, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 85% by mass or more, 90% by mass or more, 95% by mass or more, 98% by mass or more of the resin composition , 99% by mass or more, 99.5% by mass or more, 99.8% by mass or more, 99.9% by mass or more, 99.99% by mass or more, or 100% by mass of polypropylene and petroleum resin having smectica crystals; Polypropylene, petroleum resin, and other ingredients with crystals.

2. Resin Sheet The resin sheet according to one aspect of the present invention is produced using the above-described resin composition of the present invention, and can be said to contain the resin composition. In principle, the composition of the resin composition of the present invention described above is directly reflected in the resin sheet.

The resin sheet according to one aspect of the present invention has excellent transparency because the polypropylene having smectic crystals is combined with the petroleum resin. Furthermore, although it contains a petroleum resin, it can exhibit excellent impact resistance, can reduce the risk of film formation troubles such as breakage during sheet film formation, and has high handling properties.

The type, content, and other conditions of each component in the resin sheet according to one aspect of the present invention are the same as those described in “1. Resin composition”.

The thickness of the resin sheet according to one aspect of the present invention is usually 100 μm or more, preferably 150 μm or more, and more preferably 200 μm or more. Moreover, it is usually 1200 μm or less, preferably 1000 μm or less.

The resin sheet according to one aspect of the present invention preferably has a tensile modulus (MD direction) of 1400 MPa or more and 2200 MPa or less.
The resin sheet according to one aspect of the present invention preferably has a tensile elastic modulus (TD direction) of 1400 MPa or more and 2200 MPa or less.
The tensile modulus is measured by the method described in Examples.

The resin sheet according to one aspect of the present invention preferably has a yield strength (MD direction) of 23 MPa or more and 36 MPa or less.
The resin sheet according to one aspect of the present invention preferably has a yield strength (TD direction) of 23 MPa or more and 36 MPa or less.
Yield strength is measured by the method described in Examples.

The resin sheet according to one aspect of the present invention preferably has a breaking strength (MD direction) of 38 MPa or more and 50 MPa or less.
The resin sheet according to one aspect of the present invention preferably has a breaking strength (TD direction) of 34 MPa or more and 50 MPa or less.
Breaking strength is measured by the method described in Examples.

The resin sheet according to one aspect of the present invention preferably has an elongation at break (MD direction) of 300% or more and 550% or less.
The resin sheet according to one aspect of the present invention preferably has an elongation at break (TD direction) of 300% or more and 550% or less.
Breaking elongation is measured by the method described in Examples.

The resin sheet according to one aspect of the present invention preferably has a total haze of 20% or less, more preferably 15% or less, 10% or less, and even more preferably 5% or less.
The resin sheet according to one aspect of the present invention preferably has an internal haze of 15% or less, more preferably 10% or less, and even more preferably 5% or less.
Haze is measured by the method described in Examples.

The resin sheet according to one aspect of the present invention preferably has a total light transmittance of 85% or more, preferably 90% or more.
The total light transmittance is measured by the method described in Examples.

The resin sheet according to one aspect of the present invention preferably has a glossiness of 120% or more and 150% or less.
Glossiness is measured by the method described in Examples.

The resin sheet according to one aspect of the present invention preferably has an impact strength (film impact) of 1500 J/m or more and 17000 J/m or less.
Impact strength is measured by the method described in Examples.

3. Method for Producing Resin Sheet The method for producing the resin sheet of the present invention is not particularly limited, and examples thereof include an extrusion method. The extrusion method includes cooling the melt of the resin composition of the present invention described above (hereinafter referred to as the molten resin), and the cooling is preferably performed at a cooling rate of 80 ° C./sec or more, and the internal temperature of the resin sheet is below the crystallization temperature. As a result, the crystal structure of the polypropylene contained in the resin sheet can be the smectic crystal described above. The cooling rate is more preferably 90° C./second or higher, more preferably 150° C./second or higher.
A specific manufacturing method will be described in detail in Examples.

4. Laminate A laminate may be formed using the resin sheet according to one aspect of the present invention described above.
The structure of the laminate is not particularly limited as long as it includes the above resin sheet (hereinafter also referred to as "base material layer"), and may be a laminated structure of two or three layers or more. For example, "base material layer/base material layer", "base material layer/base material layer/base material layer", "base material layer/barrier layer/base material layer", "base material layer/adhesive layer/barrier layer", which will be described later. A plurality of base layers may be included, such as "layer/adhesive layer/base layer". When a plurality of substrate layers are included, the compositions of the plurality of substrate layers may be the same or different. Moreover, the thickness of the said several base material layer may be the same, and may differ.

Other layers used in the laminate according to one aspect of the present invention include, for example, a highly transparent layer, a barrier layer, an antifogging layer, an adhesive layer, and the like.

A highly transparent layer is a layer used in order to raise the transparency of a layered product more.
As the highly transparent layer, for example, polypropylene (preferably homopolypropylene), high MFR polypropylene (MFR is, for example, 2 g/10 min or more, preferably 4 g/10 min, more preferably 6 g/10 minutes or more, more preferably 8 g/10 minutes or more), and a layer containing a nucleating agent (for example, a sorbitol-based crystal nucleating agent, etc.). In addition, the highly transparent layer may contain polyethylene, and linear low density polyethylene (LLDPE) is expected to have the effect of further increasing transparency. In addition, the use of bio-polyethylene enables environmental friendliness.

Also, the highly transparent layer is preferably formed of a crystalline resin (eg, polypropylene) having a larger MFR than the adjacent lower layer (eg, base layer) and a shorter relaxation time than the adjacent lower layer (eg, transparent layer). Specifically, the highly transparent layer preferably has an MFR that is at least 1.5 times greater than that of the adjacent lower layer (for example, the substrate layer). If the MFR is less than 1.5 times, the effect of improving transparency may be small. Also, the relaxation time of the highly transparent layer is preferably 80% or less of that of the adjacent lower layer (for example, the transparent layer). If the relaxation time is more than 80%, the effect of improving transparency may be small.
The relaxation time is calculated according to the following. That is, as shown in the following formula (4), the complex elastic modulus G* (iω) measured for the resin pellet is defined as σ*/γ* by stress σ* and strain γ*, and the relaxation time τ is defined by the following formula ( 5).
G*(iω)=σ*/γ*=G′(ω)+IG″(ω) (4)
τ(ω)=G′(ω)/(ωG″(ω)) (5)
(In the formula, G' represents storage modulus and G'' represents loss modulus.)

The thickness of the highly transparent layer is usually 1 μm or more, preferably 3 μm or more. Moreover, it is usually 300 μm or less, preferably 200 μm or less.
In the laminate according to one aspect of the present invention, a plurality of highly transparent layers may be provided, for example, like "highly transparent layer/base material layer/highly transparent layer" described later. When a plurality of highly transparent layers are included, the compositions of the plurality of highly transparent layers may be the same or different. Moreover, the thickness of the plurality of highly transparent layers may be the same or different.

The barrier layer is a layer having oxygen barrier properties, and can suppress oxidative deterioration of the contents when used as a package.
Materials used for the barrier layer include, for example, ethylene-vinyl alcohol copolymer resin (EVOH), polyvinylidene chloride resin (PVDC), polyacrylonitrile resin (PAN), etc., and one of these is used alone. may be used, or two or more may be used in combination.
The barrier layer can also be formed by a coating method, and examples of materials that can be used in this case include inorganic materials such as silica, alumina, aluminum, and silicon nitride, and organic materials such as polyvinyl alcohol (PVA). and coating materials selected from the group consisting of organic-inorganic hybrid materials such as silica/PVA and the like.

The thickness of the barrier layer is usually 1 μm or more, preferably 5 μm or more. Moreover, it is usually 50 μm or less, preferably 30 μm or less.
A plurality of barrier layers may be provided in the laminate according to one aspect of the present invention. When a plurality of barrier layers are included, the composition of the plurality of barrier layers may be the same or different. Also, the thicknesses of the plurality of barrier layers may be the same or different.

The antifogging layer is a layer containing an antifogging agent, and examples of the antifogging agent include sucrose fatty acid esters, glycerin fatty acid esters, fatty acid tertiary amides, higher alcohol fatty acid esters, propylene glycol fatty acid esters, and the like. , one of these may be used alone, or two or more thereof may be used in combination.

The antifogging layer is preferably made of a resin composition in which an antifogging agent and a binder component are mixed. Examples of the binder component include, but are not particularly limited to, acrylic adhesives and the like.

In the laminate according to one aspect of the present invention, a plurality of antifogging layers may be provided. When a plurality of antifogging layers are included, the composition of the plurality of antifogging layers may be the same or different. Moreover, the thicknesses of the plurality of antifogging layers may be the same or different.

The adhesive layer is a layer that is used as necessary to enhance the adhesion of each layer of the laminate. (EVA) and the like can be used, and maleic anhydride-modified polypropylene is preferred.

The thickness of the adhesive layer is usually 1 μm or more, preferably 3 μm or more. Moreover, it is usually 20 μm or less, preferably 10 μm or less.
In the laminate according to one aspect of the present invention, a plurality of adhesive layers may be provided, for example, like "base material layer/adhesive layer/barrier layer/adhesive layer/base material layer" described later. When a plurality of adhesive layers are included, the compositions of the plurality of adhesive layers may be the same or different. Also, the thickness of the plurality of adhesive layers may be the same or different.

Examples of the laminated structure of the laminated body according to one aspect of the present invention include the structures shown below.
(1) Base layer/base layer (2) Base layer/base layer/base layer (3) Base layer/highly transparent layer (4) Highly transparent layer/base layer/highly transparent layer (5) ) Substrate layer/barrier layer (6) Substrate layer/adhesive layer/barrier layer (7) Substrate layer/barrier layer/antifogging layer (8) Substrate layer/barrier layer/substrate layer (9) Substrate Layer/adhesive layer/barrier layer/adhesive layer/base layer (“/” indicates a lamination interface.)

The thickness of the laminate according to one aspect of the present invention is preferably 100 μm or more, more preferably 150 μm or more, and even more preferably 200 μm or more. Also, it is preferably 2000 μm or less, more preferably 1500 μm or less, even more preferably 1200 μm or less, and particularly preferably 1000 μm or less.

The method for producing the laminate according to one aspect of the present invention is not particularly limited, and the resin sheet and other layers described above may be formed by co-extrusion. A barrier layer or the like may be formed by

5. Package The resin sheet or laminate according to one aspect of the present invention can be used as a package. That is, the conditions of each component constituting the resin sheet or laminate in the package and the thickness of each layer are the same as those described above.
The shape of the package is not particularly limited, and may be a sheet shape or a three-dimensional hot water container. The shape of the container may be circular, rectangular, elliptical, or various other shapes.

The package according to one aspect of the present invention can also be expressed as follows. That is, a package having at least one layer containing a polypropylene having smectic crystals and a petroleum resin, wherein the isotactic pentad fraction of the polypropylene is 80 mol% or more and 99 mol% or less, and the layer The content of the petroleum resin in is 1% by mass or more and 20% by mass or less.

Although the method for manufacturing the package according to one aspect of the present invention is not particularly limited, it is preferable to heat mold the resin sheet or laminate according to one aspect of the present invention at a temperature equal to or lower than the melting point of polypropylene described above. By doing so, it is possible to obtain a package that maintains a fine crystal structure, maintains high transparency, and has high rigidity.

The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a tensile elastic modulus (MD direction) of 3000 MPa or more and 4300 MPa or less.
The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a tensile elastic modulus (TD direction) of 3000 MPa or more and 4300 MPa or less.
The tensile modulus is measured by the method described in Examples.

The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a yield strength (MD direction) of 45 MPa or more and 55 MPa or less.
The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a yield strength (TD direction) of 45 MPa or more and 55 MPa or less.
Yield strength is measured by the method described in Examples.

The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a breaking strength (MD direction) of 38 MPa or more and 50 MPa or less.
The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a breaking strength (TD direction) of 38 MPa or more and 50 MPa or less.
Breaking strength is measured by the method described in Examples.

The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has an elongation at break (MD direction) of 3% or more and 400% or less.
The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has an elongation at break (TD direction) of 3% or more and 400% or less.
Breaking elongation is measured by the method described in Examples.

The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a total haze of 20% or less, more preferably 15% or less, 10% or less, and still more preferably 5%. % or less.
The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has an internal haze of 15% or less, more preferably 10% or less, 5% or less, still more preferably 3 % or less.
Haze is measured by the method described in Examples.

The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a total light transmittance of 85% or more, preferably 90% or more.
The total light transmittance is measured by the method described in Examples.

The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a glossiness of 100% or more and 160% or less.
Glossiness is measured by the method described in Examples.

The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has an impact strength of 900 or more. Although the upper limit is not particularly limited, it is, for example, 1500 J/m or less.
Impact strength is measured by the method described in Examples.

The sheet portion corresponding to the resin sheet (base material layer) in the package according to one aspect of the present invention preferably has a buckling strength of 20 N or more, more preferably 25 N or more.
Buckling strength is measured by the method described in Examples.

Items to be packaged include, but are not limited to, foods and beverages such as food and beverages, pharmaceuticals, medical products, cosmetics, industrial members, and electronic components.

Examples of the present invention are described below, but the present invention is not limited to these examples.

Example 1
(1) Preparation of resin composition Resin composition 1 was prepared by mixing the following polypropylene and petroleum resin in the blending amounts (% by mass) shown in Table 1.
Polypropylene 1: homopolypropylene ("F-300SP" manufactured by Prime Polymer Co., Ltd., melting point: 160 ° C., isotactic pentad fraction: [mmmm] = 92 mol%, MFR: 3 g / 10 minutes, hereinafter referred to as "PP- Also called 1.)
Petroleum resin 1: Hydrogenated petroleum resin (manufactured by Idemitsu Kosan Co., Ltd. "Imarb" (P-140), dicyclopentadiene / aromatic copolymer petroleum resin, softening point: 140 ° C., number average molecular weight: 900)

(2) Production of Resin Sheet Using the apparatus shown in FIG. 1, a resin sheet 1 made of the resin composition 1 was produced by the following method.
(Resin sheet manufacturing method (hereinafter also referred to as “manufacturing method 1”))
The resin composition 1 was extruded from the T-die 11 of the extruder, and the sheet-like material 1a was sandwiched between the metal endless belt 25 and the fourth cooling roll 22 on the first cooling roll 21 . In this state, the sheet material 1a was pressed against the first cooling roll 21 and the fourth cooling roll 22 at the arc portion corresponding to the center angle θ1 of the first cooling roll 21 and rapidly cooled.
Subsequently, the sheet-like material 1a sandwiched between the metal endless belt 25 and the fourth cooling roll 22 at the circular arc portion corresponding to the substantially lower half circumference of the fourth cooling roll 22 is brought into planar pressure contact, and cooling water is sprayed. By spraying cooling water to the back side of the metal endless belt 25 from the nozzle 26, the sheet-like material 1a was further cooled rapidly. The sprayed cooling water was recovered in the water tank 27, and the recovered water was discharged through the drainage groove 27a.
After planar pressure contact and cooling by the fourth cooling roll 22, the sheet-like material 1a adhered to the metal endless belt 25 was moved onto the second cooling roll 23 as the metal endless belt 25 was rotated. Here, the sheet-like material 1a guided by the peeling roll 29 and pressed toward the second cooling roll 23 is stretched by the metal endless belt 25 at an arc portion corresponding to substantially the upper half circumference of the second cooling roll 23, as described above. It was pressed in plane and cooled again. Water adhering to the back surface of the metal endless belt 25 was removed by a water absorption roll 28 provided on the way from the fourth cooling roll 22 to the second cooling roll 23 .
After being cooled on the second cooling roll 23 , the sheet material 1 a was separated from the metal endless belt 25 by the separation roll 29 .
The surface of the first cooling roll 21 is covered with an elastic material 21a made of nitrile-butadiene rubber (NBR). The surface of the second cooling roll 23 is also covered with an elastic material (not shown) made of nitrile-butadiene rubber (NBR).
Further, the temperature of the metal endless belt 25 can be adjusted by means of cooling means (not shown) such as a water-cooling system built in the third cooling roll 24 or the like.

The manufacturing conditions of the resin sheet 1 are as follows.
・Width of T-die 11 (size of edge of die): 900 mm
・Thickness of resin sheet 1: 0.30 mm
・Take-up speed of resin sheet 1: 3.6 m/min ・Surface temperature of fourth cooling roll 22 and metal endless belt 25: 20°C
・Cooling rate: 10,800°C/min (180°C/sec)

(3) Evaluation of resin sheet (before thermoforming treatment)
The obtained resin sheet 1 was evaluated as follows. Table 1 shows the results.

(a1) Isotactic pentad fraction The isotactic pentad fraction was measured by evaluating the ¹³ C-NMR spectrum of PP-1. Specifically, according to the assignment of peaks proposed by A. Zambelli et al. in "Macromolecules, 8, 687 (1975)", the following apparatus, conditions and calculation formulas were used.
(equipment/conditions)
Apparatus: ¹³ C-NMR apparatus ("JNM-EX400" type manufactured by JEOL Ltd.)
Method: Proton complete decoupling method (concentration: 220 mg/ml)
Solvent: 90:10 (volume ratio) mixed solvent of 1,2,4-trichlorobenzene and deuterated benzene Temperature: 130°C
Pulse width: 45°
Pulse repetition time: 4 seconds Accumulation: 10000 times (calculation formula)
Isotactic pentad fraction [mmmm] = m/S x 100
Racemic pentad fraction [rrrr] = γ/S x 100
Racemic-meso-racemic-mesopentad fraction [rmrm] = Pββ + Pαβ + Pαγ
S: Signal intensity Pββ of side chain methyl carbon atoms of all propylene units: 19.8 to 22.5 ppm
Pαβ: 18.0 to 17.5 ppm
Pαγ: 17.5 to 17.1 ppm
γ: racemic pentad chain: 20.7 to 20.3 ppm
m: mesopentad chain: 21.7 to 22.5 ppm

(a2) Crystallization speed The crystallization speed of PP-1 was measured using a differential scanning calorimeter (DSC) ("Diamond DSC" manufactured by PerkinElmer). Specifically, polypropylene is heated from 50 ° C. to 230 ° C. at 10 ° C./min, held at 230 ° C. for 5 minutes, cooled from 230 ° C. to 130 ° C. at 80 ° C./min, and then to 130 ° C. Crystallization was performed while holding. When the temperature reached 130° C., the change in heat quantity was started to obtain a DSC curve. From the obtained DSC curve, the crystallization speed was determined by the following procedures (i) to (iv).
(i) A baseline was obtained by linearly approximating the heat quantity change from the time point 10 times to the time 20 times the time from the start of measurement to the maximum peak top.
(ii) The intersection of the tangent line with a slope at the inflection point of the peak and the baseline was determined, and the crystallization start and end times were determined.
(iii) The time from the obtained crystallization start time to the peak top was measured as the crystallization time.
(iv) The crystallization rate was determined from the reciprocal of the obtained crystallization time.

(a3) Melting point The melting point of PP-1 was measured as follows. That is, using a differential scanning calorimeter (DSC) ("Diamond DSC" manufactured by PerkinElmer Japan Co., Ltd.), the polypropylene was heated from 50 ° C. to 200 ° C. at 10 ° C./min, and was heated at 220 ° C. for 5 minutes. Hold and cool from 220°C to 50°C at 10°C/min. The temperature showing the maximum value of the endothermic peak obtained at this time was taken as the melting point of polypropylene.

(a4) Crystal structure The crystal structure of PP-1 was identified by measuring the wide-angle X-ray scattering pattern under the following measurement conditions using an X-ray generator ("model ultra X 18HB" manufactured by Rigaku Corporation). As a result, in the resin sheet 1, a smectic crystal-type peak was observed even after peak separation, so it was confirmed that the resin sheet 1 contained smectic crystals.
(Measurement condition)
・Light source wavelength: Monochromatic light of 300mA CuKα ray (wavelength = 1.54Å) ・Linear output voltage/current: 50kV/250mA
・Irradiation time: 60 minutes ・Camera length: 1.085m
・Sample thickness: Sheets are stacked so that the thickness is 1.5 to 2.0 mm. The sheets are stacked so that the film-forming (MD) direction is aligned.
In order to shorten the measurement time, the sheets are stacked so that the thickness is 1.5 to 2.0 mm.

(b) Tensile Properties As tensile properties, tensile modulus, yield strength, breaking strength and breaking elongation were measured according to JIS K7161. Each measurement was made in the extrusion direction (MD direction) of molding and in the direction perpendicular to the MD direction (TD direction).

(c1) Haze Based on JISK7136, total haze and internal haze were measured using a haze meter (“NDH2000” manufactured by Nippon Denshoku Industries Co., Ltd.).

(c2) Total light transmittance Based on JISK7136, the total light transmittance was measured using a haze meter (“NDH2000” manufactured by Nippon Denshoku Industries Co., Ltd.).

(c3) Gloss In accordance with the JIS Z 8741 60-degree specular gloss measurement method, an automatic colorimetric color difference meter (manufactured by Suga Test Instruments Co., Ltd., AUD-CH-2 type-45, 60) is used. is irradiated at an incident angle of 60 degrees, and the reflected light flux ψs is measured when the reflected light is also received at 60 degrees. Glossiness was determined by
Glossiness (Gs)=(ψs/ψ0s)*100 (1)

(d) impact strength (film impact)
Using a film impact tester ("product number 181" manufactured by Yasuda Seiki Seisakusho Co., Ltd., conforming to ASTM D3420), measurement was performed at 23°C under the conditions of a test load of 6J and a 1-inch head.
Moreover, the damage degree of the resin sheet 1 after the above test was visually confirmed and evaluated according to the following criteria.
◯: Radial cracks were generated centering on the impact portion, and slight defects (holes) in the sheet were observed.
x: Defects (holes) in the sheet were clearly observed centering on the impact area.

(4) Evaluation of resin sheet (after thermoforming treatment)
For the obtained resin sheet 1, the top surface of a molded container having a flange outer diameter of 125 mm×125 mm and a depth of 25 mm was thermoformed under conditions of solid phase molding below the melting point. For the resin sheet after the treatment, the same evaluation as (b) to (d) in "(3) Evaluation of resin sheet (before heat treatment)" and the following buckling strength evaluation were performed. The buckling strength evaluation was performed for Examples 2-4. Table 2 shows the results.
(e) Buckling Strength Based on JIS K7181, buckling strength was measured under the following conditions using a universal material testing machine ("5566" manufactured by Instron). A photograph of the molded product used for the measurement is shown in FIG. The corners of the molded product are slightly rounded, but this has almost no effect on the buckling strength.
・Measurement sample: Molded product (flange outer size 125 mm x 125 mm, flange inner size 104 mm x 104 mm, top surface outer size 74 mm x 74 mm, depth 12 mm)
- Measurement conditions: test environment of 23°C, 50% RH, test speed of 10 mm/min - Calculation method: The maximum load at a compressive displacement of 2 mm or less was calculated and used as the buckling strength.
The temperature of the test environment may be 23° C.±2° C., and the humidity may be 50% RH±10% RH. Within these ranges, there is little effect on the measurement results.

Examples 2-4
A resin composition and a resin sheet were produced and evaluated in the same manner as in Example 1, except that the thickness of the resin sheet was changed as shown in Table 1. The results are shown in Tables 1 and 2.
FIG. 3 shows photographs of resin sheets after film impact evaluation (impact resistance test) in Example 2 and Comparative Example 1 described later. In the figure, Example 2 is shown on the right, and Comparative Example 1 is shown on the left.

Comparative example 1
A resin sheet was produced and evaluated in the same manner as in Example 1, except that the method for producing the resin sheet was changed to the following method. The results are shown in Tables 1 and 2.
(Resin sheet manufacturing method (hereinafter also referred to as “manufacturing method 2”))
A resin sheet was produced by the following method using the distributor system co-extrusion laminated sheet production apparatus shown in FIG. Specifically, in the manufacturing apparatus, the molten resin co-extruded from the T-die 72 of the extruder was brought into close contact with the cooling roll 76 by the air knife 74 and cooled by the cooling rolls 76 and 78 to produce the laminated sheet 71. .
The manufacturing conditions are as follows.
・Extruder diameter: 65 mm
・Width of T-die 72: 900 mm
・Take-up speed of laminated sheet 71: 3.4 m/min ・Surface temperature of cooling rolls 76 and 78: 95°C
・Cooling rate: 2,300°C/min (38°C/sec)

Comparative example 2
A resin sheet was produced and evaluated in the same manner as in Comparative Example 1, except that petroleum resin 1 was not added. The results are shown in Tables 1 and 2.

From Table 1, it can be seen that the resin sheets of Examples 1 to 4 have higher haze, total light transmittance and gloss than the resin sheets of Comparative Examples 1 and 2, and are excellent in optical properties including transparency. . In addition, as can be seen from the comparison between Comparative Examples 1 and 2, adding a petroleum resin generally significantly impairs the impact strength. It can be seen that, in some cases, the impact resistance is so excellent as to significantly exceed that of Comparative Example 2, which does not contain petroleum resin. Although the tensile properties of the resin sheets of Examples 1 to 4 are numerically inferior to those of Comparative Examples 1 and 2, they can be said to have sufficient rigidity for use.
From Table 2, it can be seen that the molded bodies (packaging bodies) obtained by thermoforming the resin sheets of Examples 1 to 4 have high rigidity and excellent transparency.

A packaging body according to an aspect of the present invention can be used for packaging foods and drinks such as beverages, pharmaceuticals, medical products, cosmetics, industrial members, electronic components, and the like.

1a sheet-like material 10 manufacturing apparatus 11 T-die 21 first cooling roll 21a elastic member 22 fourth cooling roll 23 second cooling roll 24 third cooling roll 25 metal endless belt 26 cooling water spray nozzle 27 water tank 27a drainage groove 28 water absorption Roll 29 Peeling roll θ1 Central angle 71 Laminate 72 T die 74 Air knives 76, 78 Cooling roll

Claims (16)

A resin composition comprising polypropylene having smectic crystals and a petroleum resin. The resin composition according to claim 1, wherein the polypropylene has an isotactic pentad fraction of 80 mol% or more and 99 mol% or less. 3. The resin composition according to claim 1, wherein the polypropylene has a crystallization rate at 130° C. of 2.5 min ⁻¹ or less. The resin composition according to any one of claims 1 to 3, wherein the content of the petroleum resin is 1% by mass or more and 20% by mass or less. 5. The resin composition according to any one of claims 1 to 4, which does not substantially contain a nucleating agent. A resin sheet comprising the resin composition according to any one of claims 1 to 5. 7. The resin sheet according to claim 6, having an internal haze of 15% or less. A laminate comprising the resin sheet according to claim 6 or 7. 9. The laminate according to claim 8, wherein a second layer containing polypropylene having smectic crystals is laminated on at least one surface of the resin sheet. 10. The laminate according to claim 9, wherein said second layer contains petroleum resin. 9. The laminate according to claim 8, wherein a second layer containing polypropylene and a nucleating agent is laminated on at least one surface of said resin sheet. The laminate according to any one of claims 8 to 11, having a thickness of 100 µm or more and 2000 µm or less. A package produced using the resin sheet according to claim 6 or 7 or the laminate according to any one of claims 8 to 12. A package having at least one layer containing polypropylene having smectic crystals and a petroleum resin,
The isotactic pentad fraction of the polypropylene is 80 mol% or more and 99 mol% or less,
The content of the petroleum resin in the layer is 1% by mass or more and 20% by mass or less,
package. 15. The package according to claim 13 or 14, wherein the buckling strength measured according to JIS K7181 under the following conditions is 20 N or more.
・Measurement sample shape: Flange outer size 125mm x 125mm, flange inner size 104mm x 104mm, top surface outer size: 74mm x 74mm, depth 12mm
- Measurement conditions: Test environment 23°C ± 2°C, 50% RH ± 10% RH, test speed 10 mm/min - Calculation method: Calculate the maximum load at a compressive displacement of 2 mm or less and use it as the buckling strength. A method for producing a package, comprising heat-molding the resin sheet according to claim 6 or 7 or the laminate according to any one of claims 8 to 12 at a temperature not higher than the melting point of the polypropylene.

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