JP6225159B2 - Multi-layer resin sheet for deep drawing and molded container - Google Patents

Description

  The present invention relates to a multilayer resin sheet for deep drawing and a molded container formed by molding the same.

  Conventionally, styrenic resins having excellent thermoformability and rigidity have been used as containers for soft drinks, fruit juice drinks, and favorite foods and drinks. However, in recent years, an ethylene-vinyl alcohol copolymer resin layer is provided through an adhesive layer such as a modified olefin resin in the middle of the styrene resin layer as the outermost layer to provide oxygen barrier properties, and by oxidation of the contents A multilayer resin sheet in which deterioration in quality is suppressed and a multilayer container comprising the same are widely used (Patent Document 1).

  In recent years, the number of cases in which these containers are manufactured by an integrated process of molding, filling the contents, and sealing the lid material has increased. Patent Document 2 proposes a multilayer resin sheet in which a polystyrene resin layer and a polyolefin resin layer are laminated to prevent generation of resin whiskers during stamping in the process up to the final product.

  Furthermore, Patent Document 3 proposes a multilayer resin sheet that solves the problem of insufficient notch folding after thermoforming by using a specific layer structure because the oxygen barrier resin is tough. Has been.

  In recent years, containers with complicated design shapes and deep-drawn shapes are increasing. Usually, in order to cope with such container shapes, a larger amount of heat is applied to the sheets at the time of heat forming, and the sheets are sufficiently softened and formed. It will be necessary. However, when the multilayer resin sheet described in Patent Documents 1 to 3 adopts a direct heating method in which the heat source contacts the sheet, the sheet surface may be fused to the heat source when the hot platen temperature is increased. However, there has been a problem that it cannot be used for deep drawing, which requires a higher hot plate temperature than before.

JP-A-11-58619 JP 2006-21409 A Japanese Patent No. 4758926

  The present invention has been made in view of the above circumstances, and has thermoformability, rigidity, oxygen barrier properties, is easy to impart notch breakability after thermoforming, and has a complicated shape and deep drawing. It is an object of the present invention to provide a deep drawing multilayer resin sheet that is difficult to be fused to a heat source even when a high amount of heat is applied to the container, and a molded container formed by molding the same.

  That is, the present inventor has intensively studied to develop a multilayer resin sheet having the above-mentioned characteristics and suitable for deep drawing, and as a result, the styrene-based polymer layer on both sides of the oxygen barrier resin layer via the modified olefin polymer layer. In the multilayer resin sheet in which the resin layers are laminated, adjustment of the thicknesses of the modified olefin polymer layer and the styrene resin layer on the notch forming surface side and the surface roughness (Ra of the styrene resin layer on the notch forming surface side) ), It was found that the above-mentioned problems can be solved, and the present invention has been completed.

  Therefore, according to one aspect of the present invention, the styrene resin layer is laminated on both surfaces of the oxygen barrier resin layer via the modified olefin polymer layer, and the depth at which the notch is formed from one surface side. A multilayer resin sheet for drawing, wherein the total thickness of the modified olefin polymer layer and the styrene resin layer on the one surface side is 40 to 350 μm, and one of the styrene resin layers The surface roughness (Ra) of the surface is 0.1 to 5.0 μm, and a multilayer resin sheet for deep drawing is provided.

  In the above, in one embodiment of the invention, the oxygen barrier resin layer is formed of an ethylene-vinyl alcohol copolymer resin. In one embodiment, the modified olefin polymer layer has a thickness of 10-50 μm. In one embodiment, the oxygen barrier resin layer has a thickness of 10 to 50 μm. In one embodiment, the styrene resin layer is formed from a styrene resin containing 4 to 8% by mass of a butadiene rubber component. In one embodiment, the multilayer resin sheet has a thickness of 500 to 1200 μm.

  According to another aspect of the present invention, there is provided a molded container having a notch formed from the one surface side by thermoforming the deep drawing multilayer resin sheet. .

  The multilayer resin sheet for deep drawing according to the present invention has thermoformability, rigidity and oxygen barrier properties, and imparts notch breakability after thermoforming, so that it can be melted into a heat source even when a larger amount of heat is applied during thermoforming. Since it is difficult to wear, it is easy to form into a more complex shape or deep drawn container.

It is a schematic longitudinal cross-sectional view which shows the laminated structure of the multilayer resin sheet for high heat quantity thermoforming which concerns on one Embodiment of this invention. It is a schematic perspective view which shows an example of the shaping | molding container of this invention. It is a schematic side view which shows an example of the shaping | molding container of this invention. It is the schematic for demonstrating the punching process of a container.

  The multilayer resin sheet for deep drawing according to an embodiment of the present invention has a modified olefin polymer layer (11a, 11b) on both sides of an oxygen barrier resin layer (10) as shown in FIG. It is a thermoplastic multilayer resin sheet in which styrene resin layers (12a, 12b) are laminated. A notch is formed from one surface side of the resin sheet (upper styrene resin layer 12a side in FIG. 1), but the modified olefin polymer layer (11a) and styrene resin layer on the one surface side. The total thickness of (12a) is 40 to 350 μm, and the surface roughness (Ra) of the exposed one surface of the styrene-based resin layer (12a) is 0.1 to 5.0 μm. .

  Here, “for deep drawing” means that the sheet has characteristics suitable for deep drawing, and deep drawing means the depth and width of the forming container (regardless of the shape of the forming container). It is defined that the aperture ratio, which is the ratio of the maximum width in a shape having a plurality of widths, is 0.5 or more. The deep-drawn container here is a container having a drawing ratio of 0.5 or more, preferably 0.9 or more, more preferably 1 or more, and most preferably 1.5 or more.

  Hereinafter, the thermoplastic multilayer resin sheet and a molded container produced by molding the resin sheet will be described in detail.

<Oxygen barrier resin layer (10)>
Typical examples of the oxygen barrier resin constituting the oxygen barrier resin layer include ethylene-vinyl alcohol copolymer resins and polyamide resins. Among these, ethylene-vinyl alcohol copolymer resin is preferable in terms of processability and moldability.

  The ethylene-vinyl alcohol copolymer resin is usually obtained by saponifying an ethylene-vinyl acetate copolymer, and has an ethylene content of 10 to 10 to provide oxygen barrier properties, processability, and moldability. It is preferably 65 mol%, preferably 20 to 50 mol%, and a saponification degree of 90% or more, preferably 95% or more.

  Examples of the polyamide resin include lactam polymers such as caprolactam and laurolactam, polymers of aminocarboxylic acids such as 6-aminocaproic acid, 11-aminoundecanoic acid and 12-aminododecanoic acid, hexamethylenediamine, decamethylenediamine, Aliphatic diamines such as dodecamethylenediamine, 2,2,4- or 2,4,4-trimethylhexamethylenediamine, 1,3- or 1,4-bis (aminomethyl) cyclohexane, bis (p-aminocyclohexyl) Alicyclic diamines such as methane, diamine units such as aromatic diamines such as m- or p-xylylenediamine, aliphatic dicarboxylic acids such as adipic acid, suberic acid, and sebacic acid, and alicyclics such as cyclohexanedicarboxylic acid Aromatic dica, such as dicarboxylic acid, terephthalic acid, isophthalic acid Polycondensates of a dicarboxylic acid units, such as carbon acid, and copolymers thereof, and the like.

  Specific examples of the polyamide resin include nylon 6, nylon 9, nylon 11, nylon 12, nylon 66, nylon 610, nylon 611, nylon 612, nylon 6T, nylon 6I, nylon MXD6, nylon 6/66, nylon 6 / 610, nylon 6 / 6T, nylon 6I / 6T, etc., among which nylon 6 and nylon MXD6 are preferred.

  The thickness of the oxygen barrier resin layer is preferably 10 to 50 μm, more preferably 20 to 40 μm. If it is less than 10 μm, there is a possibility that the oxygen barrier performance to the extent that the deterioration of the quality due to the oxidation of the contents of the molded container is suppressed cannot be obtained. Or notch breakage may be insufficient.

<Modified Olefin Polymer Layer (11a, 11b)>
Examples of the modified olefin polymer constituting the modified olefin polymer layer include homopolymers of olefins having about 2 to 8 carbon atoms such as ethylene, propylene, and butene-1, and these olefins and ethylene, propylene, and butene-1. Other olefins having about 2 to 20 carbon atoms such as 3-methylbutene-1, pentene-1, 4-methylpentene-1, hexene-1, octene-1, decene-1, etc., vinyl acetate, vinyl chloride, acrylic acid Olefin resins such as copolymers with vinyl compounds such as methacrylic acid, acrylic acid esters, methacrylic acid esters and styrene, ethylene-propylene copolymers, ethylene-propylene-diene copolymers, ethylene-butene-1 Olefin rubbers such as copolymers, propylene-butene-1 copolymers, acrylic acid, methacrylic acid, Unsaturated carboxylic acids such as rotonic acid, isocrotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid and tetrahydrophthalic acid, or derivatives thereof such as acid halides, amides, imides, anhydrides and esters, specifically Typical examples include those modified under the graft reaction conditions with maleyl chloride, maleimide, maleic anhydride, citraconic anhydride, monomethyl maleate, dimethyl maleate, glycidyl maleate and the like.

  As the modified olefin polymer, an ethylene resin, a propylene resin, or an ethylene-propylene or butene-1 copolymer rubber modified with an unsaturated dicarboxylic acid or an anhydride thereof, particularly maleic acid or an anhydride thereof is preferable. It is.

  The thickness of the modified olefin polymer layer is preferably 10 to 50 μm, more preferably 20 to 40 μm on either side. If it is less than 10 μm, sufficient interlayer adhesion strength may not be obtained, and if it exceeds 50 μm, resin whiskering may occur when punching a thermoformed container, or notch breakability may be insufficient. There is.

<Styrenic resin layer (12a, 12b)>
Examples of the styrene resin constituting the styrene resin layer include styrene monomers such as styrene, α-methyl styrene, p-methyl styrene, dimethyl styrene, pt-butyl styrene, and chlorostyrene, or copolymers thereof. Copolymers of styrenic monomers and other monomers, such as styrene-acrylonitrile copolymers (AS resin), or other polymers such as styrene-based monomers, such as polybutadiene, styrene-butadiene copolymers, poly Examples include graft polymers obtained by graft polymerization in the presence of diene rubbery polymers such as isoprene and polychloroprene, such as high impact polystyrene (HIPS resin) and styrene-acrylonitrile graft polymer (ABS resin).

  Among these styrene resins, polystyrene (GPPS resin) and high impact polystyrene (HIPS resin) are preferable from the viewpoints of the rigidity and moldability of the molded container.

  The styrene resin preferably contains 4 to 8% by mass of a butadiene rubber component. The butadiene rubber component content is a simple method of adjusting by blending GPPS and HIPS, but it may be adjusted at the manufacturing stage of HIPS. If it is less than 4% by mass, a practically sufficient container strength may not be obtained. If it exceeds 8% by mass, problems such as adhesion of a hot platen may occur during thermoforming.

  In the styrene resin layer, if necessary, a colorant such as a pigment or a dye, a release agent such as silicon oil or an alkyl ester, or a fibrous reinforcing agent such as glass fiber, as long as the effects of the present invention are not impaired. Additives such as particulate lubricants such as talc, clay and silica, salt compounds of sulfonic acid and alkali metal, antistatic agents such as polyalkylene glycol, ultraviolet absorbers and antibacterial agents can be added. Moreover, the scrap resin generated in the production process of the multilayer resin sheet or molded container of the present invention can be mixed and used.

  The thickness of the styrene-based resin layer (12a) on the surface side where the notch is formed is preferably 30 to 300 μm, more preferably 100 to 200 μm. If it is less than 30 μm, the styrene-based resin layer is cut off when it is stretched through thermoforming, and the modified olefin-based polymer layer is exposed, which may impair the proper printing on the container surface. Moreover, when it exceeds 300 micrometers, it is necessary to enlarge the insertion depth of the blade at the time of forming a notch, and there exists a possibility that the holding | maintenance performance and container strength of a container shape may fall.

  The thickness of the styrene-based resin layer (12b) on the surface side where no notch is formed is preferably 300 to 800 μm, more preferably 400 to 700 μm. If it is less than 300 μm, the rigidity of the container obtained by thermoforming may be insufficient, and if it exceeds 800 μm, the notch breakability after forming the notch may be lowered.

The surface roughness (Ra) of the exposed surface of the styrene resin layer (12a) on the surface side where the notch is formed is 0.1 to 5.0 μm, preferably 0.5 to 3.0 μm. . If the thickness is less than 0.1 μm, the resin layer may be easily fused to the heat source during heat molding. If the thickness exceeds 5.0 μm, the surface gloss of the obtained molded product is lost, resulting in a reduction in commercial value. May be incurred.
The surface roughness (Ra) of the exposed surface of the styrene-based resin layer (12b) on the surface side where the notch is not formed is not particularly limited, but is preferably less than 0.1 μm so as not to cause a reduction in commercial value. .

<Multi-layer resin sheet for deep drawing>
As described above, the layer structure of the deep drawing thermoplastic multilayer resin sheet according to an embodiment of the present invention is a styrene resin layer / modified olefin polymer layer / oxygen barrier resin layer / modified olefin polymer layer. / Although it is a styrene-based resin layer, for example, a multilayer resin sheet of the present invention or a layer of scrap resin generated in the manufacturing process of the molded container may be laminated on the opposite side where the notch is formed.

  The thermoplastic multilayer resin sheet for deep drawing according to an embodiment of the present invention has a total thickness of the modified olefin polymer layer (11a) and the styrene resin layer (12a) on the surface side where the notch is formed. It is 40-350 micrometers, Preferably it is 120-240 micrometers. If it is less than 40 μm, the thickness of the styrenic resin layer on the surface side where the notch is relatively formed becomes thin, and the styrenic resin layer breaks when stretched through thermoforming, which impairs the appearance and strength of the container there is a possibility. Moreover, when it exceeds 350 micrometers, it is necessary to enlarge the insertion depth of the blade at the time of forming a notch, and there exists a possibility that the holding | maintenance performance and container strength of a container shape may fall.

  The thickness of the deep drawing thermoplastic multilayer resin sheet is preferably 500 to 1200 μm, more preferably 700 to 1000 μm. If it is less than 500 μm, the strength of the container obtained by thermoforming may be insufficient, and if it exceeds 1200 μm, the production cost of the container may increase.

  The molding method of the deep drawing thermoplastic multilayer resin sheet is not particularly limited, and a general method can be used. For example, each raw resin is melt-extruded using four or more single-screw extruders, and a multilayer resin sheet is obtained using a feed block and a T die, or a multilayer resin sheet is obtained using a multi-manifold die Is mentioned.

  As a method for imparting a predetermined surface roughness to the exposed surface of the styrene resin layer in the thermoplastic multilayer resin sheet for deep drawing of the present invention, particularly the styrene resin layer (12a) on the surface side where the notch is formed, It does not specifically limit and a general method can be used. For example, when taking the molten resin, there is a method of taking it with a roll or belt that has been subjected to uneven processing in advance.

<Molded container>
2 and 3 show an example of the molded container of the present invention.

  The molded container of the present invention is formed by thermoforming the thermoplastic multilayer resin sheet of the present invention. Thermoforming methods include general vacuum forming, pressure forming, and plug assist method in which plugs are formed by contacting a plug on one side of the sheet, and male and female molds that form a pair on both sides of the sheet. A method called so-called “match mold molding” in which the molding is performed in contact with each other is exemplified, but the method is not limited thereto. Further, as a method for heating and softening the sheet before molding, a known sheet heating method such as radiant heating with an infrared heater or the like which is non-contact heating can be applied.

  The molding temperature at the time of thermoforming is appropriately set in consideration of the melting point of the resin, etc., but when performing deep drawing with a drawing ratio of 0.5 or more using the resin sheet according to the present invention, The temperature is set to 170 ° C. or higher, preferably 175 to 180 ° C. If the hot platen temperature is less than 170 ° C., the molded state of the container is insufficient due to insufficient heating, and if it is too high, there is a risk of causing problems such as fusion to the hot platen.

  The molded container of the present invention has a notch. The notch has a V-shaped cross section, and is heated by a hot plate method or the like on one surface side, that is, the side where the total thickness of the modified olefin polymer layer and the styrene resin layer is 50 to 400 μm. It can be formed by inserting a shaped blade.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to the content of an Example etc. at all.

The resin raw materials used in the examples are as follows.
(1) Oxygen barrier resin layer Ethylene-vinyl alcohol copolymer “EVAL J-102B” (manufactured by Kuraray Co., Ltd., ethylene content 32 mol%, saponification degree 99% or more)
(2) Modified olefin polymer layer “Modic F502” (Mitsubishi Chemical Corporation)
(3) Styrenic resin layer HIPS resin: “Toyostyrene H850” (Toyo Styrene Co., Ltd., butadiene content: 9.0% by mass)
GPPS resin: “HRM23” (manufactured by Toyo Styrene Co., Ltd.)

<Example 1>
Using two 40mm single screw extruders and one 65mm single screw extruder, styrenic resin layer (12a) 165μm / modified olefin polymer layer (11a) 35μm / oxygen barrier resin by feed block method Layer (10) 15 μm / modified olefin polymer layer (11b) 35 μm / styrene resin layer (12b) 650 μm, having a layer structure of 900 μm (styrene resin layer (12a) and modified olefin polymer layer ( 11a), the surface roughness (Ra) of the styrenic resin layer (12a) is a metal roll having a surface roughness (Ra) of 0.5 [mu] m. A 0.23 μm multilayer resin sheet was obtained.

<Example 2>
In the same manner as in Example 1, styrene resin layer (12a) 40 μm / modified olefin polymer layer (11a) 20 μm / oxygen barrier resin layer (10) 20 μm / modified olefin polymer layer (11b) 20 μm / The styrenic resin layer (12b) has a layer configuration of 800 μm, and has a thickness of 900 μm (total thickness of the styrene resin layer (12a) and the modified olefin polymer layer (11a) is 60 μm). A multilayer resin sheet having a surface roughness (Ra) of 0.25 μm was obtained.

<Example 3>
In the same manner as in Example 1, styrene resin layer (12a) 285 μm / modified olefin polymer layer (11a) 15 μm / oxygen barrier resin layer (10) 20 μm / modified olefin polymer layer (11b) 15 μm / The styrenic resin layer (12b) has a layer structure of 665 μm, and has a thickness of 1000 μm (total thickness of 300 μm of the styrene resin layer (12a) and the modified olefin polymer layer (11a)). A multilayer resin sheet having a surface roughness (Ra) of 0.30 μm was obtained.

<Example 4>
In the same manner as in Example 1, styrene resin layer (12a) 30 μm / modified olefin polymer layer (11a) 15 μm / oxygen barrier resin layer (10) 20 μm / modified olefin polymer layer (11b) 15 μm / The styrenic resin layer (12b) has a layer structure of 820 μm, has a thickness of 900 μm (the total thickness of the styrene resin layer (12a) and the modified olefin polymer layer (11a) is 45 μm), and the styrene resin layer (12a). A multilayer resin sheet having a surface roughness (Ra) of 0.33 μm was obtained.

<Example 5>
In the same manner as in Example 1, styrene resin layer (12a) 325 μm / modified olefin polymer layer (11a) 15 μm / oxygen barrier resin layer (10) 20 μm / modified olefin polymer layer (11b) 15 μm / The styrenic resin layer (12b) has a layer structure of 525 μm, has a thickness of 900 μm (total thickness of 340 μm of the styrene resin layer (12a) and the modified olefin polymer layer (11a)), and the styrene resin layer (12a). A multilayer resin sheet having a surface roughness (Ra) of 0.28 μm was obtained.

<Example 6>
Styrenic resin layer (12a) 165 μm / modified olefin polymer layer (11a), except that a metal roll having a rough surface with a surface roughness (Ra) of 0.3 μm was used. It has a layer structure of 20 μm / oxygen barrier resin layer (10) 20 μm / modified olefin polymer layer (11b) 20 μm / styrene resin layer (12b) 675 μm, and has a thickness of 900 μm (modified with styrene resin layer (12a)). A multilayer resin sheet having a total thickness of 185 μm of the olefin polymer layer (11a) and a surface roughness (Ra) of the styrene resin layer (12a) of 0.15 μm was obtained.

<Examples 7 to 9>
Styrenic resin layer (12a) 165 μm / modified olefin polymer layer, except that metal rolls with surface roughness (Ra) of 2, 5, and 10 μm were used, respectively, in the same manner as in Example 1. (11a) 35 μm / oxygen barrier resin layer (10) 15 μm / modified olefin polymer layer (11b) 35 μm / styrene resin layer (12b) 650 μm, having a layer structure of 900 μm (styrene resin layer (12a And a modified olefin polymer layer (11a) having a total thickness of 200 μm), and a styrene resin layer (12a) having a surface roughness (Ra) of 0.95, 2.40, and 4.70 μm, respectively. Obtained.

<Comparative Example 1>
In the same manner as in Example 1, styrene resin layer (12a) 15 μm / modified olefin polymer layer (11a) 15 μm / oxygen barrier resin layer (10) 20 μm / modified olefin polymer layer (11b) 15 μm / The styrenic resin layer (12b) has a layer structure of 835 μm, and has a thickness of 900 μm (total thickness of the styrene resin layer (12a) and the modified olefin polymer layer (11a) is 30 μm). A multilayer resin sheet having a surface roughness (Ra) of 0.35 μm was obtained.

<Comparative example 2>
In the same manner as in Example 1, styrene resin layer (12a) 360 μm / modified olefin polymer layer (11a) 15 μm / oxygen barrier resin layer (10) 20 μm / modified olefin polymer layer (11b) 15 μm / The styrenic resin layer (12b) has a layer structure of 490 μm, and has a thickness of 900 μm (total thickness of the styrene resin layer (12a) and the modified olefin polymer layer (11a) is 375 μm), and the styrene resin layer (12a) A multilayer resin sheet having a surface roughness (Ra) of 0.28 μm was obtained.

<Comparative Examples 3-6>
The styrenic resin layer (12a) is 165 μm / s in the same manner as in Example 1 except that a metal roll having a surface roughness (Ra) of 0.1, 0.2, 12, and 15 μm is used. Modified olefin polymer layer (11a) 35 μm / oxygen barrier resin layer (10) 15 μm / modified olefin polymer layer (11b) 35 μm / styrene resin layer (12b) 650 μm, with a thickness of 900 μm ( The total thickness of the styrene resin layer (12a) and the modified olefin polymer layer (11a) is 200 μm), and the surface roughness (Ra) of the styrene resin layer (12a) is 0.04, 0.07, 5. A multilayer resin sheet of 65, 7.60 μm was obtained.

<Comparative Example 7>
In the same manner as in Example 1, styrene resin layer (12a) 570 μm / modified olefin polymer layer (11a) 30 μm / oxygen barrier resin layer (10) 20 μm / modified olefin polymer layer (11b) 20 μm / The styrenic resin layer (12b) has a layer structure of 360 μm, and has a thickness of 1000 μm (total thickness of the styrene resin layer (12a) and the modified olefin polymer layer (11a) is 600 μm). A multilayer resin sheet was obtained in the same manner.

  In addition, as styrene resin, what mixed HIPS resin and GPPS resin by mass ratio 80/20 (HIPS / GPPS) was used (butadiene rubber component content: 7.2 mass%).

This multilayer resin sheet was processed in a series of steps from molding, notch formation and container punching (FIG. 4) under the following conditions to obtain the container shown in FIG. The notch was formed from the styrene resin layer 12a side, and the depth of the notch was adjusted by the heating temperature of the notch forming portion.
Equipment used: CFF-300 (manufactured by CKD Corporation)
Upper heating plate temperature: 170 ° C
Lower heating plate temperature: 170 ° C
Notch partial heating temperature: 160 ° C
Notch depth: 350 μm
Container punching blade upper structure: male blade Container punching blade lower structure: female blade Gap between upper and lower sides of container punching blade: 20 μm

  Various evaluations of the obtained multilayer resin sheet and container were performed by the following methods. The results are shown in Table 1.

(1) Surface roughness (Ra)
The surface roughness (Ra) of the sheet was measured by the following method and evaluated according to the following criteria.
[Measurement method] JIS B0601 compliant equipment used: Surfcom 120A manufactured by Tokyo Seimitsu Co., Ltd.

(2) Molded state The moldability when the container was thermoformed was evaluated according to the following criteria.
○: Good formability ×: Deformation due to adhesion of hot platen and tear of surface layer are confirmed.

(3) Notch foldability The notch formation part was bent in the bending direction shown in FIG. 3, and evaluated according to the following criteria.
○: Can be broken by bending once.
Δ: Divided by bending several times.
X: It does not crack even if it bends many times.

(4) Surface gloss of container The surface gloss of the bottom part of the molded container was measured.
[Evaluation method]
Measurement method: Conforms to JIS K7105 method Equipment used: Nippon Denshoku Digital Gloss Meter [Evaluation Criteria]
○: Glossiness of 20% or more ×: Glossiness of less than 20%

(5) Comprehensive Judgment A case where all the above evaluation results were “good” was evaluated as “good”, and a case other than that was “good”.

10 Oxygen barrier resin layers 11a, 11b Modified olefin polymer layers 12a, 12b Styrene resin layers

Claims (7)

  A styrene resin layer is laminated on both surfaces of an oxygen barrier resin layer via a modified olefin polymer layer, and a multi-layer resin sheet for deep drawing in which a notch is formed from one surface side, The total thickness of the modified olefin polymer layer and the styrene resin layer on one surface side is 40 to 350 μm, and the surface roughness (Ra) of one surface of the styrene resin layer is 0 A multilayer resin sheet for deep drawing, having a thickness of 1 to 5.0 μm.   The multilayer resin sheet for deep drawing according to claim 1, wherein the oxygen barrier resin layer is formed of an ethylene-vinyl alcohol copolymer resin.   The multilayer resin sheet for deep drawing according to claim 1 or 2, wherein the modified olefin polymer layer has a thickness of 10 to 50 µm.   The multilayer resin sheet for deep drawing according to any one of claims 1 to 3, wherein the oxygen barrier resin layer has a thickness of 10 to 50 µm.   The multilayer resin sheet for deep drawing according to any one of claims 1 to 4, wherein the styrene resin layer is formed of a styrene resin containing 4 to 8% by mass of a butadiene rubber component.   The multilayer resin sheet for deep drawing according to any one of claims 1 to 5, wherein the thickness is 500 to 1200 µm.   A molded container comprising a notch formed by thermoforming the deep drawing multilayer resin sheet according to any one of claims 1 to 6 and formed from the one surface side.

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