JPH0241411B2 - - Google Patents
Info
- Publication number
- JPH0241411B2 JPH0241411B2 JP57148752A JP14875282A JPH0241411B2 JP H0241411 B2 JPH0241411 B2 JP H0241411B2 JP 57148752 A JP57148752 A JP 57148752A JP 14875282 A JP14875282 A JP 14875282A JP H0241411 B2 JPH0241411 B2 JP H0241411B2
- Authority
- JP
- Japan
- Prior art keywords
- layer
- density polyethylene
- low
- laminate
- ethylene
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 229920001903 high density polyethylene Polymers 0.000 claims description 15
- 239000004700 high-density polyethylene Substances 0.000 claims description 15
- 229920001684 low density polyethylene Polymers 0.000 claims description 13
- 239000004702 low-density polyethylene Substances 0.000 claims description 13
- 239000000155 melt Substances 0.000 claims description 4
- 239000010410 layer Substances 0.000 description 39
- 229920001577 copolymer Polymers 0.000 description 9
- 238000004806 packaging method and process Methods 0.000 description 9
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 5
- 239000005977 Ethylene Substances 0.000 description 5
- 239000004711 α-olefin Substances 0.000 description 4
- 238000000465 moulding Methods 0.000 description 3
- 230000000704 physical effect Effects 0.000 description 3
- 229920005989 resin Polymers 0.000 description 3
- 239000011347 resin Substances 0.000 description 3
- 206010034972 Photosensitivity reaction Diseases 0.000 description 2
- 229920001519 homopolymer Polymers 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000036211 photosensitivity Effects 0.000 description 2
- 229920010126 Linear Low Density Polyethylene (LLDPE) Polymers 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 229920006242 ethylene acrylic acid copolymer Polymers 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 229920001200 poly(ethylene-vinyl acetate) Polymers 0.000 description 1
- -1 polyethylene Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 239000012748 slip agent Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
Landscapes
- Wrappers (AREA)
- Laminated Bodies (AREA)
Description
本発明は積層体に関し、詳しくは特定のメルト
インデツクス、密度および溶融流れ比（MFR）
を有する高密度ポリエチレンからなる層(A)と低密
度ポリエチレンからなる層(B)よりなり、防湿性、
光学的特性、機械的強度等の各種物性にすぐれ、
包装袋や容器等に適した積層体に関する。
従来、コピー用紙の包装袋や食器の包装袋、包
装容器など防湿性が要求される包装の分野におい
ては、高密度ポリエチレンや低密度ポリエチレン
よりなる袋や容器が用いられている。
しかし、低密度ポリエチレンは機械的強度や防
湿性が十分でなく、これらを満足させるために
は、厚肉のフイルムまたはシートとしなければな
らないという欠点がある。このため、強度的にす
ぐれた高密度ポリエチレンを用いて、薄肉化する
ことが試みられているが、耐衝撃強度の大きい通
常のフイルム用高密度ポリエチレンでは防湿性が
十分でなく、また防湿性のすぐれた特殊な高密度
ポリエチレンでは、耐衝撃強度、引裂強度共に小
さく、しかも透明性にも劣るため、フイルムの薄
肉化という要請に応えることはできなかつた。
本発明は上述の如き従来技術の欠点を解消し、
薄肉でも十分な防湿性および機械的強度を有し、
包装袋や容器等に適した積層体を提供することを
目的とするものであり、その構成は、溶融流れ比
（MFR）10〜60の高密度ポリエチレンからなる層
(A)と低密度ポリエチレンからなる層(B)よりなる積
層体である。をその構成は、メルトインデツクス
が0.2〜７ｇ／10分で、密度が0.945〜0.970ｇ／cm3
であり、かつ溶融流れ比（MFR）が10〜60であ
る高密度ポリエチレンからなる層(A)と、低密度ポ
リエチレンからなる層(B)よりなる積層体である。
本発明の積層体は基本的には(A)層と(B)層の二層
から構成されているが、ここで(A)層としては、
MFR10〜60、好ましくは15〜50の高密度ポリエ
チレンが用いられる。なお、このMFRは、荷重
21.6Kgのメルトインデツクス（MI21.6Kg）と荷重
2.16Kgのメルトインデツクス（MI21.6Kg）の比率、
すなわち、
MFR＝MI21.6Kg／MI21.6Kg
で定義されるものであり、分子量分布の指標とな
るものである。
上記(A)層を構成する高密度ポリエチレンは、上
述したMFRを有するものであり、また密度0.945
〜0.970ｇ／cm3の範囲のものである。さらにこの
高密度ポリエチレンのMIとしては、0.2〜７ｇ／
10分である。このような高密度ポリエチレンとし
ては、エチレンの単独重合体はもちろんのこと、
エチレンと他のα−オレフインとの共重合体（α
−オレフイン単位含量10モル％以下）、たとえば
エチレン−プロピレン共重合体、エチレン−ブテ
ン−１共重合体などを充当することができる。ま
た、この(A)層には、必要に応じてMFR70以上の
高密度ポリエチレンや他の樹脂、さらにはゴム類
等を適量添加することもできる。
上記高密度ポリエチレンからなる(A)層は、防湿
性にすぐれたものであるが、成形性がやや不良で
あり、また機械的強度、特に一定方向における引
裂強度が著しく小さい。そのため、本発明では、
防湿性にすぐれているが、引裂強度等の機械的強
度の小さい(A)層に、(B)層を積層して引裂強度、衝
撃強度等を向上せしめるのである。
この(B)層としては、低密度ポリエチレンが用い
られ、その性状は特に制限はないが、通常は
MI0.1〜10ｇ／10分、好ましくは0.2〜５ｇ／10
分、密度0.915〜0.935ｇ／cm3のものが用いられ
る。
このような(B)層を構成する低密度ポリエチレン
としては、エチレンの単独重合体をはじめ、エチ
レンと他のα−オレフインとの共重合体、たとえ
ばエチレン−プロピレン共重合体、エチレン−ブ
テン−１共重合体、エチレン−４−メチルペンテ
ン−１共重合体などがあり、直鎖状低密度ポリエ
チレン（LLDPE）を含むものである。さらには
エチレン−酢酸ビニル共重合体、エチレン−アク
リル酸共重合体などのエチレン−不飽和エステル
共重合体等をあげることができる。なお、ここ
で、共重合体中においてエチレンと共重合体する
成分、すなわちα−オレフインや不飽和エステル
の含有量は、１〜30モル％、好ましくは１〜20モ
ル％の範囲で定めるべきである。
この低密度ポリエチレンからなる(B)層は、衝撃
強度、引裂強度などの機械的強度にすぐれたもの
であり、前記(A)層とこの(B)層を積層したものを用
いることにより、防湿性ならびに機械的強度のす
ぐれた積層体が得られる。またこの低密度ポリエ
チレンは成形性にすぐれたものであり、安定的に
成形することができる。
本発明の積層体は、前述した如く基本的には上
記(A)、(B)両層を積層したものであるが、必要に応
じてこれらの層をさらに積層して三層以上の構造
とすることもでき、また、(A)、(B)両層の間に適当
な中間層を設けることもできる。
上記(A)層、(B)層の素材である高密度ポリエチレ
ンおよび低密度ポリエチレンを用いて、本発明の
積層体を製造するにあたつては、様々な方法があ
るが、例えばブロー比2.5〜７で共押出インフレ
ーシヨン成形したり、あるいは共押出Ｔダイ成形
法などにより、積層フイルムまたはシートを成形
する。この成形に際しては、所望により顔料、染
料、安定剤、スリツプ剤などを添加することもで
きる。
また、本発明の積層体における(A)層と(B)層の厚
さの比は、特に制限はないが、通常は(A)層／(B)層
＝90／10〜40〜60の範囲で定める。さらに、(A)
層、(B)層以外に他の層を積層する場合は、この他
層の厚さは全体の層厚の20％以下に抑えることが
好ましい。
以上の如く、本発明の積層体は、互いに物性が
異なり、かつ互いの欠点を補完しあう二層あるい
はそれ以上のポリエチレン層により構成されてい
るため、防湿性および引裂強度、衝撃強度などの
機械的強度にすぐれ、またシール性、透明性なら
びに光択が良好であり、特に両外層が低密度ポリ
エチレン層からなる積層体にあつて、透明性（霞
度）、光択が大幅に向上する。また本発明の積層
体は成形性が良く、安定的に成形を行なうことが
でき、しかも、十分な機械的強度を有するもので
あるため、薄肉化が可能であり、省資源を図るこ
とができる。
従つて本発明の積層体は、湿気を嫌うコピー用
紙や食品等の包装袋や容器、即ち防湿包装袋ある
いは容器、さらにはその透明性、光択を生かして
一般包装袋として有効に利用することができる。
次に本発明を実施例によりさらに詳しく説明す
る。
実施例 １〜９
第１表に示す所定の原料樹脂を押出機により溶
融混練し、ダイ内接着型のサーキユラーダイに導
入した後、ブロー比4.3でインフレーシヨン成形
して厚さ40μの績層フイルムを得た。得られたフ
イルムの各種物性の測定結果を第１表に示す。
比較例 １〜５
第１表に示す所定の樹脂の単層フイルムおよび
積層フイルムについて実施例１〜９と同様の測定
を行なつた。結果を第１表に示す。
The present invention relates to laminates, and more particularly to specific melt index, density and melt flow ratio (MFR)
The layer (A) is made of high-density polyethylene and the layer (B) is made of low-density polyethylene.
Excellent in various physical properties such as optical properties and mechanical strength,
This invention relates to a laminate suitable for packaging bags, containers, etc. Conventionally, bags and containers made of high-density polyethylene and low-density polyethylene have been used in the field of packaging that requires moisture resistance, such as copy paper packaging bags, tableware packaging bags, and packaging containers. However, low-density polyethylene does not have sufficient mechanical strength or moisture resistance, and in order to satisfy these requirements, it has to be made into a thick film or sheet. For this reason, attempts have been made to make the wall thinner by using high-density polyethylene, which has excellent strength, but ordinary high-density polyethylene for film, which has high impact resistance, does not have sufficient moisture resistance. Excellent special high-density polyethylene has low impact strength and tear strength, and is also inferior in transparency, so it has not been able to meet the demand for thinner films. The present invention overcomes the drawbacks of the prior art as described above,
Even with a thin wall, it has sufficient moisture resistance and mechanical strength.
The purpose is to provide a laminate suitable for packaging bags, containers, etc., and its composition consists of layers made of high-density polyethylene with a melt flow ratio (MFR) of 10 to 60.
This is a laminate consisting of (A) and a layer (B) made of low-density polyethylene. Its composition is a melt index of 0.2 to 7 g/10 minutes and a density of 0.945 to 0.970 g/ cm3.
It is a laminate consisting of a layer (A) made of high-density polyethylene and a layer (B) made of low-density polyethylene and having a melt flow ratio (MFR) of 10 to 60. The laminate of the present invention basically consists of two layers, the (A) layer and the (B) layer, where the (A) layer is
High density polyethylene with a MFR of 10-60, preferably 15-50 is used. Note that this MFR is
21.6Kg melt index (MI 21.6Kg ) and load
Melt index (MI 21.6Kg ) ratio of 2.16Kg,
That is, it is defined as MFR=MI 21.6Kg /MI 21.6Kg , and serves as an index of molecular weight distribution. The high-density polyethylene constituting the layer (A) has the above-mentioned MFR and has a density of 0.945
~0.970 g/ cm3 . Furthermore, the MI of this high density polyethylene is 0.2 to 7 g/
It's 10 minutes. Such high-density polyethylene includes, of course, ethylene homopolymer,
Copolymers of ethylene and other α-olefins (α
- olefin unit content of 10 mol % or less), such as ethylene-propylene copolymer, ethylene-butene-1 copolymer, etc. In addition, an appropriate amount of high-density polyethylene with an MFR of 70 or higher, other resins, rubbers, etc. can be added to this (A) layer, if necessary. The layer (A) made of the above-mentioned high-density polyethylene has excellent moisture resistance, but has rather poor moldability and extremely low mechanical strength, particularly tear strength in a certain direction. Therefore, in the present invention,
Layer (B) is laminated on layer (A), which has excellent moisture resistance but low mechanical strength such as tear strength, to improve tear strength, impact strength, etc. Low-density polyethylene is used for this (B) layer, and its properties are not particularly limited, but usually
MI0.1~10g/10min, preferably 0.2~5g/10
minute, density of 0.915 to 0.935 g/cm 3 is used. The low-density polyethylene constituting the layer (B) may include ethylene homopolymers, copolymers of ethylene and other α-olefins, such as ethylene-propylene copolymers, ethylene-butene-1 There are copolymers, ethylene-4-methylpentene-1 copolymers, etc., including linear low-density polyethylene (LLDPE). Further examples include ethylene-unsaturated ester copolymers such as ethylene-vinyl acetate copolymers and ethylene-acrylic acid copolymers. Note that the content of components copolymerized with ethylene in the copolymer, that is, α-olefin and unsaturated ester, should be determined in the range of 1 to 30 mol%, preferably 1 to 20 mol%. be. This layer (B) made of low-density polyethylene has excellent mechanical strength such as impact strength and tear strength, and by using a laminated layer of the above (A) layer and this (B) layer, moisture proofing is achieved. A laminate with excellent properties and mechanical strength can be obtained. Furthermore, this low-density polyethylene has excellent moldability and can be stably molded. As described above, the laminate of the present invention is basically a laminate of both layers (A) and (B), but if necessary, these layers may be further laminated to create a structure of three or more layers. It is also possible to provide a suitable intermediate layer between both layers (A) and (B). There are various methods for producing the laminate of the present invention using high-density polyethylene and low-density polyethylene, which are the materials for the above (A) layer and (B) layer. For example, a blow ratio of 2.5 In steps 7 to 7, a laminated film or sheet is formed by coextrusion inflation molding or coextrusion T-die molding. During this molding, pigments, dyes, stabilizers, slip agents, etc. may be added as desired. In addition, the ratio of the thicknesses of the (A) layer and (B) layer in the laminate of the present invention is not particularly limited, but usually (A) layer/(B) layer = 90/10 to 40 to 60. Defined by range. Furthermore, (A)
When layer other than layer (B) is laminated, the thickness of the other layer is preferably suppressed to 20% or less of the total layer thickness. As described above, the laminate of the present invention is composed of two or more polyethylene layers that have different physical properties and compensate for each other's defects, so it has excellent mechanical properties such as moisture resistance, tear strength, and impact strength. It has excellent mechanical strength, and also has good sealing properties, transparency, and photosensitivity. Particularly in the case of a laminate in which both outer layers are made of low-density polyethylene layers, the transparency (haze) and photosensitivity are greatly improved. In addition, the laminate of the present invention has good moldability, can be stably molded, and has sufficient mechanical strength, so it can be made thinner and resource saving can be achieved. . Therefore, the laminate of the present invention can be effectively used as a packaging bag or container for copy paper, food, etc. that is sensitive to moisture, that is, a moisture-proof packaging bag or container, and furthermore, by taking advantage of its transparency and optical selectivity, it can be effectively used as a general packaging bag. Can be done. Next, the present invention will be explained in more detail with reference to Examples. Examples 1 to 9 The specified raw material resins shown in Table 1 were melt-kneaded using an extruder, introduced into an in-die adhesive type circular die, and then inflation-molded at a blow ratio of 4.3 to form a laminated film with a thickness of 40μ. I got it. Table 1 shows the measurement results of various physical properties of the obtained film. Comparative Examples 1-5 The same measurements as in Examples 1-9 were carried out on single-layer films and laminated films made of the specified resins shown in Table 1. The results are shown in Table 1.
【表】【table】
Claims (1)
密度が0.945〜0.970ｇ／cm3であり、かつ溶融流れ
比が10〜60である高密度ポリエチレンからなる層
(A)と、低密度ポリエチレンからなる層(B)よりなる
積層体。 ２ 低密度ポリエチレンが、メルトインデツクス
0.1〜10ｇ／10分、密度0.915〜0.935ｇ／cm3を有す
るものである特許請求の範囲第１項記載の積層
体。[Claims] 1. Melt index is 0.2 to 7 g/10 minutes,
A layer made of high-density polyethylene with a density of 0.945 to 0.970 g/cm 3 and a melt flow ratio of 10 to 60
A laminate consisting of (A) and a layer (B) made of low-density polyethylene. 2 Low density polyethylene is melt index
The laminate according to claim 1, which has a density of 0.1 to 10 g/10 minutes and a density of 0.915 to 0.935 g/cm 3 .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14875282A JPS5938058A (en) | 1982-08-27 | 1982-08-27 | Laminate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14875282A JPS5938058A (en) | 1982-08-27 | 1982-08-27 | Laminate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5938058A JPS5938058A (en) | 1984-03-01 |
| JPH0241411B2 true JPH0241411B2 (en) | 1990-09-17 |
Family
ID=15459834
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14875282A Granted JPS5938058A (en) | 1982-08-27 | 1982-08-27 | Laminate |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5938058A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60183929A (en) * | 1984-02-28 | 1985-09-19 | 中部電力株式会社 | Protective relay system |
| JPS60242056A (en) * | 1984-05-17 | 1985-12-02 | 昭和電工株式会社 | Laminated film |
| JPS6116854A (en) * | 1984-07-04 | 1986-01-24 | 昭和電工株式会社 | Bag |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5667256A (en) * | 1979-11-05 | 1981-06-06 | Hirakawa Sangyo Kk | Cooextruding multilayer film of low density polyethylene and high density polyethylene and its manufacture |
| JPS571053A (en) * | 1980-05-29 | 1982-01-06 | Idemitsu Petrochemical Co | Bag for packing oleo-food |
| JPS5764551A (en) * | 1980-10-09 | 1982-04-19 | Mitsui Petrochemical Ind | Composite film |
-
1982
- 1982-08-27 JP JP14875282A patent/JPS5938058A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5667256A (en) * | 1979-11-05 | 1981-06-06 | Hirakawa Sangyo Kk | Cooextruding multilayer film of low density polyethylene and high density polyethylene and its manufacture |
| JPS571053A (en) * | 1980-05-29 | 1982-01-06 | Idemitsu Petrochemical Co | Bag for packing oleo-food |
| JPS5764551A (en) * | 1980-10-09 | 1982-04-19 | Mitsui Petrochemical Ind | Composite film |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5938058A (en) | 1984-03-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0145945B1 (en) | Multi-layer film | |
| US4626456A (en) | Laminate structure for collapsible dispensing container | |
| JP3483576B2 (en) | High modulus film | |
| AU616447B2 (en) | Increased regrind usage in coextruded structures | |
| JPH0241411B2 (en) | ||
| US5866267A (en) | Oriented film with improved memory | |
| JPH0675955B2 (en) | Resin laminate | |
| US7078463B2 (en) | High oxygen transmission biaxially oriented polypropylene film | |
| JP7259243B2 (en) | Polyethylene-based resin composition for sealant film containing plant-derived polyethylene and sealant film | |
| JP3096350B2 (en) | Laminated stretch shrink film | |
| JPH0334465B2 (en) | ||
| JPS6140517Y2 (en) | ||
| JPS6141749B2 (en) | ||
| JPH0242067B2 (en) | ||
| JP3112553B2 (en) | Multi-layer stretch shrink film | |
| JPS6348710B2 (en) | ||
| JP3093468B2 (en) | Laminated stretch shrink film | |
| JPH034384B2 (en) | ||
| JP3239247B2 (en) | Ethylene-based heat-shrinkable film with small amount of eluted material by n-hexane extraction | |
| JPH0357857B2 (en) | ||
| JP3573659B2 (en) | Multilayer sheets and containers | |
| JPS5859080A (en) | Laminated film | |
| JPS6321409Y2 (en) | ||
| JPS5970566A (en) | Laminate | |
| JPH022592Y2 (en) |