JPH0577591A - Transparent thermal adhesive sheet - Google Patents

Transparent thermal adhesive sheet

Info

Publication number
JPH0577591A
JPH0577591A JP3266908A JP26690891A JPH0577591A JP H0577591 A JPH0577591 A JP H0577591A JP 3266908 A JP3266908 A JP 3266908A JP 26690891 A JP26690891 A JP 26690891A JP H0577591 A JPH0577591 A JP H0577591A
Authority
JP
Japan
Prior art keywords
sensitive adhesive
heat
adhesive sheet
weight
adhesive layer
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.)
Granted
Application number
JP3266908A
Other languages
Japanese (ja)
Other versions
JP3032625B2 (en
Inventor
Morio Matsuzaki
盛雄 松崎
Tatsuya Watanabe
達也 渡辺
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sanyo Kokusaku Pulp Co Ltd
Dow Mitsui Polychemicals Co Ltd
Original Assignee
Du Pont Mitsui Polychemicals Co Ltd
Sanyo Kokusaku Pulp Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=17437336&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=JPH0577591(A) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Du Pont Mitsui Polychemicals Co Ltd, Sanyo Kokusaku Pulp Co Ltd filed Critical Du Pont Mitsui Polychemicals Co Ltd
Priority to JP3266908A priority Critical patent/JP3032625B2/en
Publication of JPH0577591A publication Critical patent/JPH0577591A/en
Application granted granted Critical
Publication of JP3032625B2 publication Critical patent/JP3032625B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Abstract

PURPOSE:To obtain a transparent thermal adhesive sheet with superb thermal adhesion and peel-off properties after adhesion when using it as an information propagation medium as well as with a high suitableness for production. CONSTITUTION:The subject transparent thermal adhesive sheet consists of a transparent support 1, a thermally plastic resin layer 2 which can be peeled off from one surface of the support 1 and thermal adhesive layers 3, 3' formed on both surfaces of the sheet. At least, the thermal adhesive layer 3 on the side where the thermally plastic resin layer 2 is provided, contains an ethylene/ vinyl acetate copolymer with a copolymerization ratio of vinylacetate limited to the range of 3 to 35wt.%, adhesion-donative resin ranging from 5 to 40 pts.wt. for 100 pts.wt. of the ethylene/vinyl acetate copolymer, roll lubricant ranging from 0.05 to 10 pts.wt., an antiblocking agent ranging from 0.1 to 15 pts.wt. and/or a slip agent ranging from 0.1 to 1 pt.wt.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は透明感熱接着シートに関
し、特に文字等の情報が記録された二枚の記録材の各々
の記録面を剥離可能に熱接着し、葉書等の郵送情報に機
密性を持たせるに適した透明感熱接着シートに関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent heat-sensitive adhesive sheet, and in particular, two recording materials on which information such as characters are recorded are heat-bonded so that they can be peeled off, and confidential to postal information such as postcards. The present invention relates to a transparent heat-sensitive adhesive sheet suitable for imparting properties.

【0002】[0002]

【従来技術】近年、消費生活或いは社会生活が高度化・
複雑化したことに伴い、税金の請求書、証券の満期通知
書、年金の支払い通知書、預貯金の満期通知書、クレジ
ットの請求書、電信電話・ガス・水道・電気の各請求
書、学校の授業料の支払い通知書等の個人情報、即ちプ
ライバシーに係わる書類が郵便により送付される場合が
激増している。このようなプライバシーに係わる書類
は、従来封書により郵送されていたが、これらの書類の
増大に伴い、郵送コストが莫大にならざるを得ないとい
う欠点があった。
2. Description of the Related Art In recent years, consumer and social life has become more sophisticated.
Due to the complexity, tax bills, securities maturity notices, pension payment notices, deposit and maturity notices, credit bills, telephone, gas, water, electricity bills, school bills The number of cases in which personal information such as tuition payment notices, that is, documents related to privacy, are sent by mail has increased dramatically. Conventionally, such documents related to privacy have been mailed in sealed letters, but with the increase in these documents, there is a disadvantage in that the mailing cost has to be enormous.

【0003】係る欠点を解決するために、文字等の情報
を記録した二枚の記録材の記録面同士を感熱接着シート
を介して熱接着することにより、受信人が、何れか一方
の記録材を剥離することにより内部に記録された情報を
読み取るまでは、記載された情報を秘密に保つことがで
きるようにした葉書等の情報伝達媒体が提案され、良好
な結果を納めている。
In order to solve the above drawbacks, the recording surfaces of two recording materials on which information such as characters are recorded are heat-bonded to each other via a heat-sensitive adhesive sheet, so that the receiver receives one of the recording materials. An information transmission medium such as a postcard has been proposed in which the written information can be kept secret until the information recorded inside is read by peeling off, and has achieved good results.

【0004】このような情報伝達媒体に使用する感熱接
着シートには、感熱接着シートに熱接着した何れか一方
の記録材を容易に剥離(剥離性という)することができ
ること、及び記録情報の印刷方式や印刷濃度に影響され
ることなく、記録材の記録面(単に記録材という)に対
する感熱接着性が優れていること等が要求される。
In the heat-sensitive adhesive sheet used for such an information transmission medium, either one of the recording materials heat-bonded to the heat-sensitive adhesive sheet can be easily peeled off (referred to as peelability), and the recording information is printed. It is required that the heat-sensitive adhesiveness to the recording surface of the recording material (simply referred to as recording material) is excellent without being affected by the method and the print density.

【0005】このような記録材に対する感熱接着性を良
好なものとするためには、一般的に、感熱接着シートの
感熱接着剤層に使用する樹脂を、融点・軟化点及びガラ
ス転移点等の熱的物性値が低い、柔軟な樹脂とすること
が必要である。
In order to improve the heat-sensitive adhesiveness to such a recording material, in general, the resin used for the heat-sensitive adhesive layer of the heat-sensitive adhesive sheet has a melting point, a softening point and a glass transition point. It is necessary to use a flexible resin having low thermal properties.

【0006】しかしながら、このような熱的物性値の低
い樹脂を、溶融押出しラミネートによってシート上に樹
脂被膜(感熱接着剤層)状に設けた場合には、該樹脂被
膜と冷却ロールとの剥離性(リリース性)が悪くなるた
め、高速でラミネート加工することができなくなるのみ
ならず、感熱接着シートを巻き取って保存した場合に、
シート同士が付着するブロッキング現象が発生し、シー
トの製造効率が悪化するという欠点があった。
However, when such a resin having a low thermal physical property value is provided on the sheet in the form of a resin coating (heat-sensitive adhesive layer) by melt extrusion lamination, the resin coating and the cooling roll can be easily separated from each other. (Release property) deteriorates, so it is not possible to laminate at high speed, and when the heat-sensitive adhesive sheet is wound and stored,
There is a drawback in that a blocking phenomenon occurs in which the sheets adhere to each other and the sheet manufacturing efficiency deteriorates.

【0007】所で、既に公知の感熱接着シートとして
は、プラスチックシートの両面にプラスチックシートと
の接着力が互いに異なる感熱接着剤層を設けた積層体、
或いは該積層体のプラスチックシートと感熱接着剤層の
一方の間に離型剤層を設け、接着力により大きな差を持
たせた積層体、又はプラスチックシートの一方の面に熱
可塑性樹脂層を形成させたシートの両面或いは熱可塑性
樹脂層と反対の面に感熱接着剤層を設けた、4層又は3
層の感熱接着シートが提案されている(例えば、透明感
熱接着シート:実開平2−25546号、情報伝達カー
ド:実開平2−142066号、実開平2−14206
7号、実開平2−142068号) 。
By the way, as a known heat-sensitive adhesive sheet, a laminate having a heat-sensitive adhesive layer having different adhesive strengths with the plastic sheet on both sides of the plastic sheet,
Alternatively, a release agent layer is provided between the plastic sheet and one of the heat-sensitive adhesive layers of the laminate, and a thermoplastic resin layer is formed on one side of the laminate or the plastic sheet having a large difference in adhesive force. 4 layers or 3 layers in which a heat-sensitive adhesive layer is provided on both surfaces of the formed sheet or on the surface opposite to the thermoplastic resin layer
A layered heat-sensitive adhesive sheet has been proposed (for example, transparent heat-sensitive adhesive sheet: Jitsukaihei 2-25546, information transmission card: Jitsukaihei 2-142066, Jiikaihei 2-14206.
No. 7, No. 2-142068 of Kaikaidaira).

【0008】しかしながら、これらの提案においては、
何れも感熱接着剤層に使用することのできる樹脂として
アクリル系樹脂、酢酸ビニル系樹脂、塩化ビニリデン系
樹脂或いはそれらの具体例としてEVA(エチレン−酢
酸ビニル共重合体)、PE(ポリエチレン)、EEA
(エチレン−アクリル酸エチル共重合体)、EAA(エ
チレンアクリル酸共重合体)樹脂等を挙げているのみで
あり使用する樹脂の軟化点、融点或いはガラス転移点等
の熱的性質は特に問題とされておらず、例えば、実開平
2−25546号においては、単に100℃以下で透明
性を害しないものであれば良いとされている。従って、
従来の感熱接着シートにおいては、良質のものを十分に
効率良く製造することが困難であった。
However, in these proposals,
Acrylic resins, vinyl acetate resins, vinylidene chloride resins or their specific examples include EVA (ethylene-vinyl acetate copolymer), PE (polyethylene), EEA as resins that can be used in the heat-sensitive adhesive layer.
(Ethylene-ethyl acrylate copolymer), EAA (ethylene acrylate copolymer) resin, etc. are only mentioned, and the thermal properties such as the softening point, melting point or glass transition point of the resin used are particularly problematic. No. However, for example, in Japanese Utility Model Laid-Open No. 25546/1990, it suffices as long as it does not impair transparency at 100 ° C. or lower. Therefore,
In the conventional heat-sensitive adhesive sheet, it was difficult to produce a good quality sheet sufficiently efficiently.

【0009】特に、プラスチックシートの両面にプラス
チックシートとの接着力が互いに異なる感熱接着剤層を
設けた積層体にあっては、接着力の差が近接している場
合には、該積層体の両面に熱接着することにより設けた
記録材を均一に剥離することができないので、記録材が
部分的に剥がれ、記録材の裏面に記録された情報を読み
取ることが困難となる場合が生じるという欠点があった
(例えば、プラスチックシートとその両面の各感熱接着
剤層との接着強度が、各々25〜30g/mmの範囲と
5〜20g/mmの範囲である場合には、係る欠点が生
じる(実開平2−142068号))。
Particularly, in the case of a laminated body in which heat-sensitive adhesive layers having different adhesive strengths to the plastic sheet are provided on both sides of the plastic sheet, when the difference in adhesive strength is close, Since the recording material provided by thermally adhering on both sides cannot be uniformly peeled off, the recording material may be partially peeled off, and it may be difficult to read the information recorded on the back surface of the recording material. (For example, when the adhesive strength between the plastic sheet and each heat-sensitive adhesive layer on both sides thereof is in the range of 25 to 30 g / mm and 5 to 20 g / mm, such a defect occurs ( (Actual number 2-142068))).

【0010】[0010]

【発明が解決しようとする課題】本発明者等は、上記欠
点を解決すべく鋭意検討した結果、熱可塑性樹脂を透明
支持体の一方の面に設けたシートの両面に感熱接着剤層
を設け、少なくとも熱可塑性樹脂層を設けた側の感熱接
着剤層に特定の成分を含有させることにより、良好な透
明感熱接着シートを得ることができることを見出し本発
明に到達した。従って、本発明の目的は、情報伝達媒体
として使用する場合の熱接着性及び接着後の剥離性に優
れると共に、製造適性に優れた透明感熱接着シートを提
供することにある。
DISCLOSURE OF THE INVENTION The inventors of the present invention have made earnest studies to solve the above-mentioned drawbacks, and as a result, provided a heat-sensitive adhesive layer on both sides of a sheet provided with a thermoplastic resin on one side of a transparent support. The present inventors have found that a good transparent heat-sensitive adhesive sheet can be obtained by containing a specific component in at least the heat-sensitive adhesive layer on the side where the thermoplastic resin layer is provided. Therefore, an object of the present invention is to provide a transparent heat-sensitive adhesive sheet which is excellent in thermal adhesiveness when used as an information transmission medium and in peelability after adhesion, and which is also excellent in production suitability.

【0011】[0011]

【課題を解決するための手段】本発明の上記の目的は、
透明支持体の一方の面に該支持体から剥離可能な熱可塑
性樹脂層を設けてなるシートの両面に感熱接着剤層を設
けた透明感熱接着シートであって、少なくとも前記熱可
塑性樹脂層を設けた側の前記感熱接着剤層が、酢酸ビニ
ル(VA)の共重合比が3〜35重量%の範囲であるエ
チレン酢酸ビニル共重合体(EVA共重合体)、並びに
該エチレン酢酸ビニル共重合体100重量部に対して、
5〜40重量部の範囲の粘着付与樹脂、0.05〜10
重量部の範囲の離ロール剤並びに0.1〜15重量部の
範囲のブロッキング防止剤及び/又は0.1〜1重量部
の範囲のスリップ剤を含有することを特徴とする透明感
熱接着シートによって達成された。
The above objects of the present invention are as follows.
A transparent heat-sensitive adhesive sheet having a heat-sensitive adhesive layer on both sides of a sheet comprising a thermoplastic resin layer releasable from the support on one surface of the transparent support, wherein at least the thermoplastic resin layer is provided. The heat-sensitive adhesive layer on the open side has an ethylene vinyl acetate (VA) copolymerization ratio in the range of 3 to 35% by weight (EVA copolymer), and the ethylene vinyl acetate copolymer For 100 parts by weight,
Tackifying resin in the range of 5-40 parts by weight, 0.05-10
A transparent heat-sensitive adhesive sheet characterized by containing a releasing agent in the range of 1 part by weight, an antiblocking agent in the range of 0.1 to 15 parts by weight and / or a slip agent in the range of 0.1 to 1 part by weight. Achieved

【0012】本発明で熱可塑性樹脂層に使用する樹脂
は、支持体との剥離性を良好にする観点から、20℃、
65%RHの環境下での300mm/分の剥離速度にお
ける支持体からのT型剥離強度が10〜200g/50
mmであると共に感熱接着剤層との接着性が良好な熱可
塑性樹脂である。
The resin used in the thermoplastic resin layer in the present invention is 20 ° C. from the viewpoint of improving the releasability from the support.
T-type peel strength from the support at a peeling speed of 300 mm / min in an environment of 65% RH is 10 to 200 g / 50.
It is a thermoplastic resin having a thickness of mm and good adhesiveness with the heat-sensitive adhesive layer.

【0013】このような熱可塑性樹脂は、ガラス転移温
度が25〜120℃の範囲であるか若しくはビカット軟
化温度が70℃以下、好ましくは40〜68℃の範囲で
ある樹脂の中から適宜選択することができる。上記熱可
塑性樹脂の具体例としては、例えば、アクリル樹脂、ニ
トリルゴム、塩素化ポリオレフィン樹脂、塩化ビニル/
酢酸ビニル共重合樹脂、塩化ビニル/プロピオン酸ビニ
ル共重合樹脂、アセタール樹脂、ナイロン樹脂、エチレ
ン共重合ポリオレフィン樹脂又はこれらの二種以上の併
用物等を挙げることができる。
Such a thermoplastic resin is appropriately selected from resins having a glass transition temperature of 25 to 120 ° C. or a Vicat softening temperature of 70 ° C. or less, preferably 40 to 68 ° C. be able to. Specific examples of the thermoplastic resin include acrylic resin, nitrile rubber, chlorinated polyolefin resin, vinyl chloride /
Examples thereof include vinyl acetate copolymer resin, vinyl chloride / vinyl propionate copolymer resin, acetal resin, nylon resin, ethylene copolymer polyolefin resin, and a combination of two or more of these.

【0014】このような熱可塑性樹脂を有する感熱接着
シートの場合には、感熱接着剤層と支持体との接着強度
が熱可塑性樹脂層と支持体との接着強度の約5倍である
ので、それを2枚の記録材の間に挟んで熱接着させ、一
体化させた場合、該記録材のみを容易且つ均一に剥離す
ることができる。
In the case of a heat-sensitive adhesive sheet having such a thermoplastic resin, the adhesive strength between the heat-sensitive adhesive layer and the support is about 5 times the adhesive strength between the thermoplastic resin layer and the support. When it is sandwiched between two recording materials and heat-bonded to be integrated, only the recording material can be peeled easily and uniformly.

【0015】熱可塑性樹脂層を支持体上に設けること
は、後記する溶融樹脂ラミネート法又は熱可塑性樹脂の
塗工液をロールコーター等の公知の塗工手段を用いて支
持体上にラミネート又は塗工することにより容易に行う
ことができる。
The thermoplastic resin layer is provided on the support by laminating or coating the melted resin laminating method described below or a coating solution of the thermoplastic resin on the support using a known coating means such as a roll coater. It can be easily done by working.

【0016】本発明において、熱可塑性樹脂層を設けた
側の感熱接着剤層(樹脂側感熱接着剤層という)に使用
するエチレン酢酸ビニル共重合体(以下EVA共重合体
という)の酢酸ビニル(以下VAという)の共重合比は
3〜35重量%とすることが好ましく、特に6〜30重
量%とすることが好ましい。
In the present invention, the vinyl acetate of ethylene-vinyl acetate copolymer (hereinafter referred to as EVA copolymer) (hereinafter referred to as EVA copolymer) used for the heat-sensitive adhesive layer on the side provided with the thermoplastic resin layer (hereinafter referred to as the resin-side heat-sensitive adhesive layer) The copolymerization ratio (hereinafter referred to as VA) is preferably 3 to 35% by weight, and particularly preferably 6 to 30% by weight.

【0017】VA共重合比が3重量%未満のEVA共重
合体を使用すると、支持体或いは印刷紙等の記録材との
接着性が充分でないのみならず、印刷紙等の記録材に熱
接着させる場合に、高温を必要とするので好ましくな
い。VA共重合比が35重量%以上のEVA共重合体を
使用すると、溶融押出しラミネート法により感熱接着シ
ートを製造する場合に、該感熱接着剤層と冷却用ロール
とのリリース性が悪くなるのみならず、感熱接着シート
を巻き取った場合に、感熱接着シート同士が接着すると
いうブロッキングが発生し易くなるので好ましくない。
When an EVA copolymer having a VA copolymerization ratio of less than 3% by weight is used, not only the adhesion to a support or a recording material such as a printing paper is not sufficient, but also a thermal adhesion to a recording material such as a printing paper is performed. In that case, high temperature is required, which is not preferable. If an EVA copolymer having a VA copolymerization ratio of 35% by weight or more is used, when a heat-sensitive adhesive sheet is produced by a melt extrusion laminating method, the release property between the heat-sensitive adhesive layer and the cooling roll is deteriorated. However, when the heat-sensitive adhesive sheet is wound up, blocking that the heat-sensitive adhesive sheets adhere to each other easily occurs, which is not preferable.

【0018】本発明において、樹脂側感熱接着剤層に使
用する粘着性付与樹脂は特に限定されるものではなく、
感熱接着剤層に接着性を付与することのできる公知の樹
脂の中から適宜選択して使用することができる。このよ
うな樹脂としては、各種ロジン、テルペン樹脂、クマロ
ン・インデン樹脂、脂肪族炭化水素樹脂、脂環族炭化水
素樹脂、芳香族炭化水素樹脂等を挙げることができる。
これらの中でも、特にEVA共重合体と相溶性が良く且
つ無臭性である脂環族炭化水素樹脂の一種である、水素
化芳香族炭化水素樹脂が好適である。
In the present invention, the tackifying resin used for the resin-side heat-sensitive adhesive layer is not particularly limited,
The heat-sensitive adhesive layer can be appropriately selected and used from known resins capable of imparting adhesiveness to the heat-sensitive adhesive layer. Examples of such resins include various rosins, terpene resins, coumarone-indene resins, aliphatic hydrocarbon resins, alicyclic hydrocarbon resins, aromatic hydrocarbon resins and the like.
Among these, a hydrogenated aromatic hydrocarbon resin, which is a kind of alicyclic hydrocarbon resin which has good compatibility with the EVA copolymer and is odorless, is particularly preferable.

【0019】本発明においては、感熱接着剤層中にEV
A共重合体100重量部に対して粘着性付与樹脂を5〜
40重量部の範囲で含有させることが好ましく、特に1
0〜35重量部含有させることが好ましい。粘着性付与
樹脂の含有量を10重量部以下とすると、感熱接着剤層
と印刷紙等の記録材との接着性が劣ることとなり、40
重量部以上とすると該感熱接着剤層と冷却用ロールとの
リリース性が悪くなるのみならず、ブロッキングが発生
し易くなるので、何れも好ましくない。
In the present invention, EV is incorporated in the heat-sensitive adhesive layer.
A tackifying resin is added in an amount of 5 to 100 parts by weight of the A copolymer.
It is preferable to contain in the range of 40 parts by weight, especially 1
It is preferable to contain 0 to 35 parts by weight. If the content of the tackifying resin is 10 parts by weight or less, the adhesiveness between the heat-sensitive adhesive layer and the recording material such as printing paper will be inferior.
If the amount is more than the weight part, not only the release property of the heat-sensitive adhesive layer and the cooling roll is deteriorated, but also blocking is likely to occur, which is not preferable.

【0020】本発明においては、感熱接着シートの製造
時に、冷却ロールとのリリース性を良くするために離ロ
ール剤を樹脂側感熱接着剤層に含有させる。尚、これに
よりブロッキングの発生を防止する効果も生ずる。上記
離ロール剤としては、例えば、ポリエチレングリコー
ル、水添ひまし油、ポリエチレンワックス等のワックス
類を挙げることができる。
In the present invention, at the time of producing the heat-sensitive adhesive sheet, a releasing agent is contained in the resin-side heat-sensitive adhesive layer in order to improve the release property with the cooling roll. Note that this also has the effect of preventing the occurrence of blocking. Examples of the release agent include waxes such as polyethylene glycol, hydrogenated castor oil, and polyethylene wax.

【0021】本発明においては、離ロール剤をEVA共
重合体100重量部に対して0.05〜10重量部、樹
脂側感熱接着剤層中に含有させることが好ましく、特に
ポリエチレングリコールや水添ひまし油の場合には0.
05〜1重量部、又ワックス類の場合には1〜10重量
部、特に1〜8重量部含有させることが好ましい。離ロ
ール剤の含有量を少なくし過ぎるとリリース性を良好に
することができず、含有量を多くし過ぎると感熱接着剤
層の接着性が劣ることとなり、溶融押出しラミネート加
工が困難となるので、何れも好ましくない。
In the present invention, it is preferable to add 0.05 to 10 parts by weight of the releasing agent to the resin-side heat-sensitive adhesive layer with respect to 100 parts by weight of the EVA copolymer, and especially polyethylene glycol or hydrogenated. In the case of castor oil, 0.
It is preferable that the content is 05 to 1 part by weight, and 1 to 10 parts by weight, particularly 1 to 8 parts by weight in the case of waxes. If the content of the release roll agent is too small, the release property cannot be improved, and if the content is too large, the adhesiveness of the heat-sensitive adhesive layer becomes poor, and the melt extrusion laminating process becomes difficult. However, neither is preferable.

【0022】本発明においては、感熱接着シートの製造
時におけるブロッキングを防止したり感熱接着シートを
ロールに巻き取る際の滑り性を良くするために、樹脂側
感熱接着剤層にブロッキング防止剤及び/又はスリップ
剤を含有させる。上記ブロッキング防止剤としては、例
えば、微粉状のシリカやタルク等の無機化合物を挙げる
ことができる。
In the present invention, in order to prevent blocking during production of the heat-sensitive adhesive sheet and to improve slipperiness when winding the heat-sensitive adhesive sheet on a roll, an anti-blocking agent and / or an anti-blocking agent is added to the resin-side heat-sensitive adhesive layer. Alternatively, a slip agent is included. Examples of the anti-blocking agent include finely powdered inorganic compounds such as silica and talc.

【0023】本発明においては、ブロッキング防止剤を
樹脂側感熱接着剤層中にEVA共重合体100重量部に
対して0.1〜15重量部含有させることが好ましく、
特に0.3〜10重量部含有させること好ましい。ブロ
ッキング防止剤の含有量を0.1重量部以下とする場合
には、スリップ剤によって補完する必要がある。又、ブ
ロッキング防止剤の含有量を15重量部以上とした場合
には感熱接着剤層の接着性が劣ることとなり、溶融押出
しラミネート加工が困難となり、好ましくない。
In the present invention, the antiblocking agent is preferably contained in the resin-side heat-sensitive adhesive layer in an amount of 0.1 to 15 parts by weight based on 100 parts by weight of the EVA copolymer.
It is particularly preferable to contain 0.3 to 10 parts by weight. When the content of the anti-blocking agent is 0.1 part by weight or less, it is necessary to supplement with a slip agent. On the other hand, if the content of the antiblocking agent is 15 parts by weight or more, the adhesiveness of the heat-sensitive adhesive layer is deteriorated and the melt extrusion laminating process becomes difficult, which is not preferable.

【0024】前記スリップ剤としては、エルカ酸アミド
等の飽和又は不飽和の各種の脂肪酸アミド類を挙げるこ
とができる。本発明においては、スリップ剤を、樹脂側
感熱接着剤層中にEVA共重合体100重量部に対して
0.1〜1重量部含有させることが好ましく、特に0.
1〜0.5重量部含有させることが好ましい。スリップ
剤の含有量を多くし過ぎると、溶融押出しラミネート加
工が困難となり好ましくない。又、スリップ剤の使用量
を0.1重量部以下とする場合には、ブロッキング防止
剤の使用量を調節して補完する必要がある。
Examples of the slip agent include various saturated or unsaturated fatty acid amides such as erucic acid amide. In the present invention, the slip agent is preferably contained in the resin-side heat-sensitive adhesive layer in an amount of 0.1 to 1 part by weight based on 100 parts by weight of the EVA copolymer.
It is preferable to contain 1 to 0.5 parts by weight. If the content of the slip agent is too large, melt extrusion lamination processing becomes difficult, which is not preferable. Further, when the amount of the slip agent used is 0.1 parts by weight or less, it is necessary to adjust the amount of the antiblocking agent to be supplemented.

【0025】本発明においては、樹脂側感熱接着剤層中
に、必要に応じて、適宜ポリエチレンやエチレン共重合
体を含有させることもできる。本発明において、熱可塑
性樹脂層を設けない側の支持体面に設ける感熱接着剤層
(支持体側感熱接着剤層という)に使用する樹脂として
は、前記樹脂側感熱接着剤層に使用した樹脂を使用する
こともできるが、一般に、記録材を熱接着することので
きる樹脂の中から適宜選択して使用することができる。
特に90℃近辺で記録材を熱接着することのできるEV
A系樹脂を使用することが好ましい。
In the present invention, the resin-side heat-sensitive adhesive layer may appropriately contain polyethylene or an ethylene copolymer, if necessary. In the present invention, the resin used for the resin-side heat-sensitive adhesive layer is used as the resin for the heat-sensitive adhesive layer (referred to as support-side heat-sensitive adhesive layer) provided on the support surface on the side where the thermoplastic resin layer is not provided. However, in general, the recording material can be appropriately selected and used from the resins capable of being heat-bonded.
An EV that can heat-bond recording materials around 90 ° C
It is preferable to use an A-based resin.

【0026】上記支持体側感熱接着剤層には、必要に応
じて、前記熱可塑性樹脂層の上に設けた感熱接着剤層中
に含有せしめた粘着付与樹脂、離ロール剤、ブロッキン
グ防止剤及びスリップ剤等を含有させることもできる。
The support-side heat-sensitive adhesive layer may contain, if necessary, a tackifying resin, a release roll agent, an antiblocking agent and a slip contained in the heat-sensitive adhesive layer provided on the thermoplastic resin layer. Agents and the like can also be included.

【0027】本発明において使用する透明支持体は、特
に限定されるものではなく、公知の透明支持体の中から
適宜選択して使用することができる。上記透明支持体と
しては、例えば、ポリエチレンテレフタレートフィル
ム、ポリプロピレンフィルム、ポリエチレンフィルム、
アセテートフィルム、ポリカーボネートフィルム等を挙
げることができる。
The transparent support used in the present invention is not particularly limited and can be appropriately selected and used from known transparent supports. Examples of the transparent support include polyethylene terephthalate film, polypropylene film, polyethylene film,
An acetate film, a polycarbonate film, etc. can be mentioned.

【0028】本発明においては、以上のようにして各々
調製した感熱接着剤層用の樹脂組成物を加熱溶融混練
し、押出し成形機のダイスより該溶融樹脂組成物を押出
し、可塑性樹脂層を一方の面に設けた支持体の片面或い
は両面にラミネートする、溶融押し出しラミネート法を
採用することが好ましい。
In the present invention, the resin composition for the heat-sensitive adhesive layer prepared as described above is melted and kneaded by heating, and the molten resin composition is extruded from a die of an extrusion molding machine to form a plastic resin layer on one side. It is preferable to employ a melt extrusion laminating method in which one side or both sides of the support provided on the surface (1) are laminated.

【0029】このようにして支持体の可塑性樹脂層側に
設ける感熱接着剤層は、190℃、2160gの荷重に
おけるメルトフローレートが1〜150g/10分及び
ビカット軟化温度が70℃以下に調整されることが好ま
しく、特にメルトフローレートが3〜100g/10分
及びビカット軟化温度が40〜60℃に調整されること
が好ましい。
The heat-sensitive adhesive layer thus provided on the plastic resin layer side of the support is adjusted to have a melt flow rate of 1 to 150 g / 10 minutes at a load of 190 ° C. and 2160 g and a Vicat softening temperature of 70 ° C. or less. It is preferable to adjust the melt flow rate to 3 to 100 g / 10 minutes and the Vicat softening temperature to 40 to 60 ° C.

【0030】次に、図面に従って更に本発明を詳述す
る。図1は本発明の透明感熱接着シートの断面概略図で
ある。図から明らかな如く、本発明の透明感熱接着シー
トは、透明支持体1の一方の面に熱可塑性樹脂2及び感
熱接着剤層3が順次設けられると共に、透明支持体の他
方の面に感熱接着剤層3’が設けられている。
Next, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a schematic sectional view of the transparent heat-sensitive adhesive sheet of the present invention. As is clear from the figure, the transparent heat-sensitive adhesive sheet of the present invention has the thermoplastic resin 2 and the heat-sensitive adhesive layer 3 sequentially provided on one surface of the transparent support 1, and the heat-sensitive adhesive on the other surface of the transparent support. An agent layer 3'is provided.

【0031】図2は本発明の透明感熱接着シートを使用
し、情報を記録した記録材5及び5’を前記シートを介
して熱接着した情報伝達媒体の1例の断面概略図であ
る。図から明らかな如く、該情報伝達媒体の構造は、文
字等の情報が記録された記録材5及び5’の記録面が透
明感熱接着シート4を介して貼り合わされた構造となっ
ている。
FIG. 2 is a schematic cross-sectional view of an example of an information transmission medium in which the transparent heat-sensitive adhesive sheet of the present invention is used and the recording materials 5 and 5'on which information is recorded are thermally adhered via the sheet. As is clear from the figure, the structure of the information transmission medium is such that the recording surfaces of the recording materials 5 and 5'on which information such as characters is recorded are bonded together via the transparent heat-sensitive adhesive sheet 4.

【0032】従って、例えば、これを郵便葉書用の媒体
として使用した場合においても、記録材に記録された文
字等の情報が外部から読み取られることがないので、情
報の秘密性が保たれる。又、感熱接着剤層3及び3’に
熱接着されている記録材5及び5’は、熱可塑性樹脂層
2と透明支持体1との間の接着力が弱いのでその間から
容易に剥がされ記録材5’及び記録材5に記録された情
報を容易に読み取ることができる。
Therefore, for example, even when this is used as a medium for a postcard, the information such as characters recorded on the recording material is not read from the outside, so that the confidentiality of the information is maintained. Further, the recording materials 5 and 5'which are heat-bonded to the heat-sensitive adhesive layers 3 and 3'have a weak adhesive force between the thermoplastic resin layer 2 and the transparent support 1 and therefore are easily peeled off from between and recorded. The information recorded on the material 5 ′ and the recording material 5 can be easily read.

【0033】尚、感熱接着剤層3と熱可塑性樹脂層2、
感熱接着剤層3’と支持体1、感熱接着剤層3及び感熱
接着剤層3’と記録材5の間の各々のT型剥離強度は、
20℃、65RH%の環境下及び300mm/分の剥離
速度で、300g/mm以上の剥離強度であるので、本
発明の感熱接着シートは、葉書等とした場合の通常の取
扱で必要とされる充分な接着性を有しており、又、これ
らの界面から剥離することはない。
The heat-sensitive adhesive layer 3 and the thermoplastic resin layer 2,
The T-type peel strength between the heat-sensitive adhesive layer 3 ′ and the support 1, the heat-sensitive adhesive layer 3 and between the heat-sensitive adhesive layer 3 ′ and the recording material 5 is
Since the peeling strength is 300 g / mm or more in an environment of 20 ° C. and 65 RH% and a peeling speed of 300 mm / min, the heat-sensitive adhesive sheet of the present invention is required for normal handling when used as a postcard or the like. It has sufficient adhesiveness and does not peel off from these interfaces.

【0034】[0034]

【発明の効果】以上詳述した如く、本発明の透明感熱接
着シートは、情報伝達媒体とした場合の感熱接着性及び
接着後の剥離性に優れると共に、製造適性に優れてい
る。
As described above in detail, the transparent heat-sensitive adhesive sheet of the present invention is excellent in heat-sensitive adhesiveness when used as an information transmission medium and in peelability after adhesion, and is also excellent in manufacturing suitability.

【0035】[0035]

【実施例】以下本発明を実施例により、更に詳述する
が、本発明はこれによって限定されるものではない。
EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited thereto.

【0036】実施例1〜3及び比較例1〜8.厚さ16
μmの透明ポリエステルフィルム支持体の一方の面に、
熱可塑性樹脂層として、ガラス転移温度57℃のポリビ
ニルブチラール樹脂(PVB)を、溶融押出しラミネー
トにより厚さが7μmとなるように設けた後、得られた
シートの両面に表1に示した成分の混合物を溶融混合
し、厚さが20μmとなるように溶融押出しラミネート
して感熱接着剤層を設け、実施例1〜3及び比較例1〜
8の透明感熱接着シートを得た。尚、実施例の場合の透
明感熱接着シートの感熱接着剤層は、何れも記録材と良
好に熱接着することのできる接着剤層であった。
Examples 1 to 3 and Comparative Examples 1 to 8. Thickness 16
On one side of the μm transparent polyester film support,
As a thermoplastic resin layer, a polyvinyl butyral resin (PVB) having a glass transition temperature of 57 ° C. was provided by melt extrusion lamination so as to have a thickness of 7 μm, and the components shown in Table 1 were formed on both surfaces of the obtained sheet. The mixture is melt-mixed, melt-extruded and laminated to a thickness of 20 μm to form a heat-sensitive adhesive layer, and Examples 1 to 3 and Comparative Examples 1 to 1 are provided.
A transparent heat-sensitive adhesive sheet 8 was obtained. The heat-sensitive adhesive layers of the transparent heat-sensitive adhesive sheets in the examples were all adhesive layers capable of excellent heat adhesion to the recording material.

【0037】次いで、コンピューター用プリンターで情
報を印字記録した、葉書大で秤量80g/m2 の二枚の
記録紙の記録面の間に、得られた各透明感熱接着シート
を挟み、その積層物を表面温度が100〜110℃の2
つの熱ロール間に通して熱接着した後充分冷却し、一体
化した葉書大の情報伝達媒体を作製した。
Then, each of the obtained transparent heat-sensitive adhesive sheets was sandwiched between the recording surfaces of two recording papers having a postcard size and a weight of 80 g / m 2 on which information was printed and recorded by a computer printer, and a laminate thereof was formed. The surface temperature is 100 ~ 110 ℃ 2
After passing through two heat rolls for thermal bonding, they were sufficiently cooled to prepare an integrated postcard-sized information transmission medium.

【0038】得られた透明感熱接着シート及び情報伝達
媒体について、下記の主な性能試験を行って評価した結
果は、表2に示した通りである。 (1)感熱接着剤層の記録材に対する接着性 秤量80g/m2 の2枚の上質紙のUV4色印刷した面
間に透明感熱接着シートを挟み、シールを行った後、前
記上質紙を剥離し、感熱接着剤層の印刷面に対する接着
強さの度合いを評価した。評価基準は以下の通りであ
る。 ○:良好 △:やや劣る ×不良
Table 2 shows the evaluation results of the following main performance tests of the obtained transparent heat-sensitive adhesive sheet and information transmission medium. (1) Adhesiveness of heat-sensitive adhesive layer to recording material A transparent heat-sensitive adhesive sheet is sandwiched between two UV-color-printed surfaces of two pieces of wood-free paper weighing 80 g / m 2 and the paper is peeled off after sealing. Then, the degree of adhesive strength of the heat-sensitive adhesive layer to the printed surface was evaluated. The evaluation criteria are as follows. ◯: Good Δ: Slightly inferior × Bad

【0039】(2)耐ブロッキング性感熱接着剤層面同
士を重ねた感熱接着シートに100g/m2 の荷重を掛
け、55℃で24時間放置した後、圧着度合いを評価し
た。評価基準は以下の通りである。 ○:良好 △:やや劣る ×不良
(2) Blocking resistance A heat-sensitive adhesive sheet having the heat-sensitive adhesive layer surfaces stacked on each other was subjected to a load of 100 g / m 2 and left at 55 ° C. for 24 hours, and then the degree of pressure bonding was evaluated. The evaluation criteria are as follows. ◯: Good Δ: Slightly inferior × Bad

【0040】(3)冷却ロールからのリリース性 感熱接着シートをロールに巻きつけた後、該シートを剥
がしシートのロールへの接着強さの度合を評価した。評
価基準は以下の通りである。 ○:良好 △:やや劣る ×不良
(3) Releasability from cooling roll After the heat-sensitive adhesive sheet was wound around the roll, the sheet was peeled off and the degree of adhesive strength of the sheet to the roll was evaluated. The evaluation criteria are as follows. ◯: Good Δ: Slightly inferior × Bad

【0041】(4)支持体との接着性 情報伝達媒体を引き剥がした際に、感熱接着剤層と支持
体間で剥離が生じるか否かを目視により観察した。 ○:全く剥離しない △:やや剥離 ×:剥離部が多く
記録情報の判読に支障がでる。
(4) Adhesiveness with Support The presence or absence of peeling between the heat-sensitive adhesive layer and the support when the information transmission medium was peeled off was visually observed. ◯: No peeling at all Δ: Slightly peeling ×: Many peeled portions interfere with reading of recorded information.

【0042】(5)シートの巻き取り適性 感熱接着シートをロールに巻き取る際に巻きズレ及び巻
きシワが発生することなく適正に巻き取れるか否かを評
価した。評価基準は以下の通りである。 ○:良好 △:やや劣る ×不良
(5) Suitability for Winding of Sheet It was evaluated whether or not the heat-sensitive adhesive sheet could be wound properly without winding deviation and winding wrinkles when wound on a roll. The evaluation criteria are as follows. ◯: Good Δ: Slightly inferior × Bad

【0043】 (6)剥離力(熱可塑性樹脂層と支持体界面における) 秤量80g/m2 の2枚の上質紙のUV4色印刷した面
の間に透明感熱接着シートを挟み、90℃で熱接着を行
い、冷却した後、上質紙同士を、20℃、65%RH
で、300mm/分の剥離速度で剥離した場合のT型剥
離強度を測定し、評価した。
(6) Peeling force (at the interface between the thermoplastic resin layer and the support) A transparent heat-sensitive adhesive sheet is sandwiched between the UV four-color printed surfaces of two pieces of woodfree paper weighing 80 g / m 2 and heated at 90 ° C. After bonding and cooling, the high-quality papers are put together at 20 ° C and 65% RH.
The T-type peel strength when peeled at a peeling speed of 300 mm / min was measured and evaluated.

【表1】 [Table 1]

【表2】 [Table 2]

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の透明感熱接着シートの断面概略図であ
る。
FIG. 1 is a schematic sectional view of a transparent heat-sensitive adhesive sheet of the present invention.

【図2】本発明の透明感熱接着シートを使用した情報伝
達媒体の1例の断面概略図である。
FIG. 2 is a schematic sectional view of an example of an information transmission medium using the transparent heat-sensitive adhesive sheet of the present invention.

【符号の説明】[Explanation of symbols]

1 透明支持体 2 熱可塑性樹脂層 3 感熱接着剤層 3’感熱接着剤層 4 感熱接着シート 5 記録材 5’記録材 1 transparent support 2 thermoplastic resin layer 3 heat-sensitive adhesive layer 3'heat-sensitive adhesive layer 4 heat-sensitive adhesive sheet 5 recording material 5'recording material

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 透明支持体の一方の面に該支持体から剥
離可能な熱可塑性樹脂層を設けてなるシートの両面に感
熱接着剤層を設けた透明感熱接着シートであって、少な
くとも前記熱可塑性樹脂層を設けた側の前記感熱接着剤
層が、酢酸ビニルの共重合比が3〜35重量%の範囲で
あるエチレン酢酸ビニル共重合体、並びに該エチレン酢
酸ビニル共重合体100重量部に対して、5〜40重量
部の範囲の粘着付与樹脂、0.05〜10重量部の範囲
の離ロール剤並びに0.1〜15重量部の範囲のブロッ
キング防止剤及び/又は0.1〜1重量部の範囲のスリ
ップ剤を含有することを特徴とする透明感熱接着シー
ト。
1. A transparent heat-sensitive adhesive sheet having a heat-sensitive adhesive layer on both sides of a sheet comprising a thermoplastic resin layer releasable from the support on one surface thereof, wherein the heat-sensitive adhesive sheet comprises at least the heat-sensitive adhesive sheet. The heat-sensitive adhesive layer on the side provided with the plastic resin layer has an ethylene vinyl acetate copolymer having a vinyl acetate copolymerization ratio in the range of 3 to 35% by weight, and 100 parts by weight of the ethylene vinyl acetate copolymer. On the other hand, a tackifying resin in the range of 5 to 40 parts by weight, a release agent in the range of 0.05 to 10 parts by weight, and an antiblocking agent in the range of 0.1 to 15 parts by weight and / or 0.1 to 1 part. A transparent heat-sensitive adhesive sheet comprising a slip agent in a range of parts by weight.
【請求項2】 感熱接着剤層が、溶融押出しラミネート
法により設けられてなる請求項1に記載の透明感熱接着
シート。
2. The transparent heat-sensitive adhesive sheet according to claim 1, wherein the heat-sensitive adhesive layer is provided by a melt extrusion laminating method.
【請求項3】 感熱接着剤層を形成する感熱接着剤のメ
ルトフローレートが、190℃、2160g荷重におい
て1〜150g/10分であると共に、ピカット軟化温
度が70℃以下である請求項1又は2に記載の透明感熱
接着シート。
3. The heat-sensitive adhesive forming the heat-sensitive adhesive layer has a melt flow rate of 190 ° C. and a load of 1 to 150 g / 10 minutes under a load of 2160 g, and a Vicat softening temperature of 70 ° C. or lower. 2. The transparent heat-sensitive adhesive sheet according to 2.
JP3266908A 1991-09-19 1991-09-19 Transparent heat-sensitive adhesive sheet Expired - Fee Related JP3032625B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3266908A JP3032625B2 (en) 1991-09-19 1991-09-19 Transparent heat-sensitive adhesive sheet

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3266908A JP3032625B2 (en) 1991-09-19 1991-09-19 Transparent heat-sensitive adhesive sheet

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JPH0577591A true JPH0577591A (en) 1993-03-30
JP3032625B2 JP3032625B2 (en) 2000-04-17

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0888908A3 (en) * 1997-06-30 2001-02-07 Tohcello Co., Ltd. Decorative wooden material coated with resin composite film and process for producing the same
US6365254B1 (en) * 1998-02-02 2002-04-02 3M Innovative Properties Company Roll stabilizing release liner
US6492017B1 (en) * 1999-11-13 2002-12-10 Tesa Ag Self-adhesive highly transparent protective article for automobile windows and other sensitive surfaces

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0225546U (en) * 1988-08-05 1990-02-20
JPH0351120A (en) * 1989-07-19 1991-03-05 Goyo Shiko Kk Heat sealable and hidable laminating material

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0225546U (en) * 1988-08-05 1990-02-20
JPH0351120A (en) * 1989-07-19 1991-03-05 Goyo Shiko Kk Heat sealable and hidable laminating material

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0888908A3 (en) * 1997-06-30 2001-02-07 Tohcello Co., Ltd. Decorative wooden material coated with resin composite film and process for producing the same
US6365254B1 (en) * 1998-02-02 2002-04-02 3M Innovative Properties Company Roll stabilizing release liner
US6492017B1 (en) * 1999-11-13 2002-12-10 Tesa Ag Self-adhesive highly transparent protective article for automobile windows and other sensitive surfaces

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