JP2007268818A - Information concealing sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a concealing type postcard being inexpensive and excellent in convenience and having recyclability. <P>SOLUTION: At the time when a paper piece 2 for concealing information is folded back along a fold line 3 and laid on a paper piece 1 for entering information after release paper 4 is peeled off, the paper piece 2 for concealing information is adhered to the paper piece 1 for entering information, through the medium of a transparent adhesive layer 23. When the paper piece 2 is peeled off thereafter from the paper piece 1, release occurs between an ultraviolet curing resin layer 22 and a release agent layer 21 and an information entering part 2b on a paper piece for entering concealed information is brought to a state of being covered by the ultraviolet curing resin layer 22 in this information concealing sheet X1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an information hiding sheet capable of hiding information entered on a sheet surface.

The information concealment sheet is used to conceal information by entering concealment information on a piece of information entry paper, and then overlaying and concealing the piece of concealment paper on the entry surface, and peeling the concealment piece from the piece of information entry paper when necessary. It can be used to read concealed information, and is often used for direct mail sent by companies to specific members, and for information concealment postcards used when mailing personal information and account numbers to various reporting organizations. It's being used.
In the information concealment sheet, in order to prevent concealment information from being read by a third party and to prevent falsification of additional information, there is known an information concealment sheet which is configured so that it cannot be pasted again after the pieces of paper in a pasted state are once peeled off. As this type of information hiding sheet that cannot be re-bonded, a sheet having a film layer such as a laminate film is used (the following Patent Documents 1 and 2).
JP-A-11-198565 JP-A-8-244104

However, since the sheet having this film layer is manufactured separately from the information entry sheet having the information entry part, the complicated work process of overlapping and adhering them in the production process or concealing the information is performed. Cost.
In addition, when there is a film layer, there is a drawback in that it is difficult to separate the base paper layer and the film layer when recycling as used paper material and it is difficult to recycle.
Then, the main subject of this invention is providing the information concealment sheet | seat which can manufacture easily, can be bonded without complicated operation, and becomes impossible for rebonding after peeling operation | work.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
Having an information entry sheet piece and a concealment sheet piece connected via a folding line;
The information concealment sheet, wherein the concealment sheet piece has a layer structure in which a base paper layer, a release agent layer, a transparent ultraviolet curable resin layer, and a transparent adhesive layer are laminated in this order.

<Invention of Claim 2>
The information hiding sheet according to claim 1, wherein the release agent layer is mainly composed of a cationic polymerization ultraviolet curable silicone release agent.

<Invention of Claim 3>
The information hiding sheet according to claim 1, wherein a sealing layer is provided between the base paper layer and the release agent layer.

In the information hiding sheet of the present invention, a sealing layer, a release agent layer, an ultraviolet curable resin layer, and a transparent adhesive layer are laminated in this order on one side of the base paper. Therefore, when the information concealment paper piece is folded at the fold line and overlapped with the information entry paper piece, the information concealment paper piece is adhered to the information entry paper piece via the adhesive layer, and further after the adhesion, the information concealment paper piece When the piece is peeled from the information entry sheet piece, the piece is peeled between the ultraviolet curable resin layer and the release agent layer. And since the adhesive surface of the concealment information entry paper piece surface is covered with the UV curable resin layer after peeling, the fact that the information concealment paper piece cannot be reattached and information is read by a third party is the fact. Can be confirmed.
The transparency of the transparent UV curable resin layer and the transparent pressure-sensitive adhesive layer in the present invention and the specification is the state in which the transparent pressure-sensitive adhesive layer and the transparent UV curable resin layer are laminated, and characters and figures below it are visually visible. It only needs to have a recognizable range of transparency, and is not particularly limited as long as it is within these ranges. Therefore, it may be semi-transparent and does not mean complete transparency.
On the other hand, in the information concealment sheet of the present invention, the information concealment sheet piece and the information concealment sheet piece are connected via a folding line, so there is no risk of the information concealment sheet being lost.
In addition, all the layers can be formed by a simple method such as printing or coating, so that each piece of paper can be formed with a common base sheet, which facilitates manufacture.
Furthermore, since it does not have a film layer, it is excellent in recyclability.

  Next, embodiments of the present invention will be described in detail below with reference to the drawings. This embodiment is an example in which the information hiding sheet of the present invention is adopted for the hiding postcard X1. 1 is a view showing the front side of the concealed postcard X1 of the present invention before use, FIG. 2 is a view showing the back side, FIG. 3 is a view taken along the line III-III, and FIG. 4 is a concealed postcard X1. FIG. 5 is a view taken along the line V-V of FIG. 5, FIG. 6 is a diagram showing a state of the concealment type postcard X1 after peeling the piece of information concealment paper, and FIG. FIG. 8 is a view showing the front side of another form X2 of the concealment type postcard, and FIG. 9 is a view showing the back side thereof.

  In the concealment type postcard X 1, an information entry sheet piece 1 and an information concealment sheet piece 2 of the same size are connected by a folding line 3. The information entry sheet piece 1 and the information concealment sheet piece 2 are formed from one common base paper and share the base paper layer 12. The fold line 3 is formed by perforations so that the information-hiding paper piece 2 can be easily folded back, and can be separated if necessary. The method for forming the perforation 3 is not particularly limited. It can be formed by a conventionally known method.

  The information entry sheet piece 1 has a copy-forgery-inhibited pattern printing M on the front side 1A and a concealment information entry part 1b on the back side 1B. The information concealment sheet piece 2 has an address information entry part 2a on the front surface side 2A, and the back surface side 2B has a layer structure in which a release agent layer 21, a transparent ultraviolet curable resin layer 22, and a transparent adhesive layer 23 are laminated in this order. Have

  The transparent pressure-sensitive adhesive layer 23 is covered and protected by the release paper 4 in order to prevent adhesion of the pressure-sensitive adhesive layer 23 to an unintended part before bonding.

  Various types of paper such as high-quality paper, art paper, coated paper, craft paper, lightweight coated paper, and synthetic paper can be used as the base paper constituting each paper piece. High quality paper, coated paper, art paper, and impregnated paper are preferable. Although there is no restriction | limiting in particular in the thickness of a base paper, Preferably, it is 50-300 micrometers. The base paper needs to be made of an opaque material so that the concealment information on the back surface cannot be read. As for the opacity of the base paper, the opacity specified in JIS P 8149 is desirably 90% or more. In consideration of recyclability, a pulp fiber as the main raw material is preferably used.

  The release agent layer 21 is formed by applying a release agent to one area of the information hiding paper of the base paper 12. As the release agent, known release agents such as silicone, long-chain alkyl polymer, polyolefin, alkyd resin, fluorine compound and the like can be used. In particular, a release agent mainly composed of cationic polymerization ultraviolet curable silicone is preferable, and a release agent made of cationic polymerization ultraviolet curable silicone is particularly preferable. Such a release agent is desirable in that it does not suffer from curing inhibition by oxygen in the atmosphere and does not need to be cured in a nitrogen-substituted atmosphere. The cationic polymerization ultraviolet curable silicone is a mixture containing a known polyorganosiloxane having an epoxy functional group in the molecule and a known onium salt polymerization initiator.

The coating amount of the release agent, is about 0.1-5 g / m ^2. If it is less than 0.1 g / m ² , peeling of the ultraviolet curable resin layer 22 is insufficient, and even if it exceeds 5 g / m ² , the improvement of the peeling effect is not observed and only the cost is increased. The release agent can be applied by coating with various conventional coating machines such as an air knife coater, a blade coater, a rod metering coater, a curtain coater, and a roll coater. In particular, printing coating by various printing such as offset printing, gravure printing, letterpress printing, stencil printing, etc., in which it is easy to appropriately adjust the coating amount and coating distribution of the release agent by pattern printing or solid printing, is suitable.

  Although not provided in the illustrated example, a sealing layer is provided between the release agent layer 21 and the base paper 12 in accordance with the type and viscosity of the release agent in order to suppress the penetration of the release agent into the base paper 12. Can be provided. As the sealing layer, those having particularly high affinity with the release agent are suitable. The sealing layer can be formed by applying a sealing agent to the base paper. The sealant is a coating containing an inorganic pigment or organic pigment used for coated paper such as coated paper, a water-soluble polymer or latex for bonding them, and an auxiliary agent such as a lubricant added as necessary. Depending on the release agent used for the release agent layer 21 from among the working fluid, oxidation polymerization type offset printing ink added with various fats and oils, heat drying type printing ink added with various fats and oils, etc. You can choose. In particular, if a release agent comprising a cationic polymerization UV curable silicone or a release agent comprising a cationic polymerization UV curable silicone is used as a release agent, it does not contain amines and various basic substances that are curing inhibitors. It is desirable not to migrate the material from the base paper layer. In addition, when a colorant is mixed in advance with the sealing agent for forming the sealing layer to make the sealing layer colored, the information concealing property when the information concealing paper piece 2 is superimposed on the information entry paper piece 1 is enhanced.

  As a method for applying the sealant, conventionally known methods such as bar coating, knife coating, roll coating, blade coating, die coating, gravure coating, offset printing, relief printing, gravure printing, stencil printing, etc. Various printing methods can be used. The thickness of the sealing layer 21 is usually 3 to 50 μm, preferably 5 to 25 μm.

  The ultraviolet curable resin layer 22 can be formed by applying an ultraviolet curable resin on the release agent layer 21 and then curing it by irradiating with ultraviolet rays. The ultraviolet curable resin layer itself is cured and has no adhesiveness. Examples of the ultraviolet curable resin include unsaturated polyester resins, acrylate resins, and methacrylate resins. Epoxy acrylates, urethane acrylates, polyester acrylates, and the like are particularly preferable. In addition, known initiators such as benzophenone-based, acetophenone-based, and thioxanthone-based initiators that are contained in the ultraviolet curable resin and initiate photopolymerization can be used.

  The UV curable resin coating method is a conventionally known method such as a bar coating method, knife coating method, roll coating method, blade coating method, die coating method, gravure coating method, offset printing, relief printing, gravure printing, stencil printing, etc. Various printing methods can be used. The thickness of the ultraviolet curable resin layer 22 is preferably 3 to 50 μm, and preferably 5 to 25 μm, in consideration of fee costs associated with an increase in postcard weight and a decrease in convenience due to an increase in thickness.

  The transparent adhesive layer 23 can be formed by applying a transparent adhesive on the ultraviolet curable resin layer 22. As such a transparent pressure-sensitive adhesive, for example, a natural rubber-based, acrylic-based, silicone-based, polyurethane-based, or polyester-based pressure-sensitive adhesive used for known label applications can be used. Further, an organic solvent system, an emulsion system, or a hot melt system may be used. Examples of the acrylic pressure-sensitive adhesive include, as a main component, an acrylic ester homopolymer, a copolymer containing two or more acrylic ester units, and a copolymer of an acrylic ester and another functional monomer. What contains at least 1 sort (s) chosen from the inside is used. Examples of the acrylic ester include (meth) acrylic acid butyl ester, (meth) acrylic acid pentyl ester, (meth) acrylic acid hexyl ester, (meth) acrylic acid heptyl ester, (meth) acrylic acid octyl ester, (meth ) Acrylic acid nonyl ester, (meth) acrylic acid decyl ester and the like. Examples of the functional monomer include hydroxyl group-containing monomers such as (meth) acrylic acid hydroxyethyl ester and (meth) acrylic acid hydroxypropyl ester, and amides such as (meth) acrylamide and dimethyl (meth) acrylamide. Examples thereof include group-containing monomers and carboxylic acid group-containing monomers such as (meth) acrylic acid. In addition, the acrylic pressure-sensitive adhesive has alkali solubility, water solubility or water redispersibility so as not to cause inconvenience in the disaggregation process and the recycling process in the recycling process of the paper to which it is attached. Can also be used. Examples of the rubber-based adhesive include, as a main component, natural rubber, polyisoprene rubber, polyisobutylene rubber, polybutadiene rubber, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, and the like. Those containing at least one selected are used.

These transparent pressure-sensitive adhesives are blended with a tackifier, a crosslinking agent, a filler and the like as desired. As the tackifier, such as rosin-based resins, natural resins such as polyterpene resins, C ₅ based, C ₉ type, DCPD petroleum resins, coumarone-indene resins, synthetic resins such as xylene resins. Examples of the crosslinking agent include polyisocyanate compounds, epoxy resins, melamine resins, urea resins, metal chelate compounds, metal salts and the like. Examples of the filler include zinc white, titanium oxide, silica, calcium carbonate and the like.

  As a coating method of the transparent adhesive, conventionally known methods such as bar coating method, knife coating method, roll coating method, blade coating method, die coating method, gravure coating method, offset printing, relief printing, gravure printing, stencil printing, etc. Various printing methods can be used. The thickness of an adhesive layer is 5-30 micrometers normally, Preferably it is the range of 10-20 micrometers.

  The release paper 4 is, for example, a paper base such as high-quality paper, glassine paper, coated paper, laminated paper obtained by laminating a thermoplastic resin such as polyethylene on these paper bases, or polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc. There are no particular restrictions on the thickness of the release paper 4, although there are no particular restrictions on the thickness of the release paper 4, such as those obtained by applying a release agent such as silicone resin to a plastic film such as a polyolefin film such as polypropylene or polyethylene. Degree.

Next, the information concealment operation and reading operation of the concealment type postcard X1 of this embodiment will be described in detail with respect to the relationship between the layers.
First, information to be concealed is entered in the concealment information entry unit 1b using a writing instrument or the like.
Thereafter, the release paper 4 is peeled off to expose the transparent adhesive layer 23. The release paper 4 is transparent adhesive so that when the release paper 4 is peeled off, the transparent adhesive layer 23 is removed from the release paper 4 and delamination does not occur between the release agent layer 21 and the UV curable resin layer 22. The peel strength is adjusted so that the agent layer 23 can be easily peeled off. Specifically, the peel strength is adjusted to about 3 to 25 N / 25 mm.

  After the release paper 4 is peeled off to expose the transparent adhesive layer 23, the information concealment paper piece 2 is folded back at the fold line 3, and the exposed surface of the transparent adhesive layer is the back side of the information entry paper piece 1 (concealment information entry). As shown in FIGS. 4 and 5, the information concealment sheet piece 2 and the information entry sheet piece 1 are bonded together to cover and conceal the concealment information entry part 1b. Here, the transparent adhesive layer 23 prevents the concealment information entered in the concealment information entry part 1b from being unintentionally peeled off when the information concealment piece 2 is unintentionally bonded to the information entry piece 1. Therefore, appropriate tackiness is required. The adhesive force can be adjusted by a conventionally known method. For example, it can be adjusted by adjusting the solid content concentration of the pressure-sensitive adhesive. Here, since the concealment type postcard X1 of this embodiment peels between the release agent layer 21 and the ultraviolet curable resin layer 22 when the information concealment paper piece 2 is peeled again as described later, the transparent adhesive layer 23 is strong. It can be adhesive force.

  Thereafter, the postcard X1 is mailed based on the address information described in the address information description section, and the recipient receives the postcard X1 in the information concealment state. Then, the person who should read the concealment information such as the recipient peels the information concealment sheet piece 2 from the information entry sheet piece 1 when reading the information entered in the concealment information entry part 1b. The peel strength between the information concealment paper piece 2 and the information entry paper piece 1 can be the same as the peel strength of the information concealment sheet in a general known concealment type postcard. The peel strength between the information concealment paper piece 2 and the information entry paper piece 1 is 4 to 30 N / 25 mm, preferably 6 to 20 N /, in the case of measuring the 180-degree peeling adhesive strength in 10 of JIS Z 0237. It is preferable to be about 25 mm.

  Here, in the postcard X1 of this embodiment, the adhesive force between the ultraviolet curable resin layer 22 and the release agent layer 21 is weak due to the presence of the release agent layer 21, and at the time of release, the release agent layer 21 and the ultraviolet curable resin layer 22 are weak. Delamination occurs between the two. Accordingly, the ultraviolet curable resin layer 22 remains on the information entry sheet piece 1 side due to the adhesive force of the transparent adhesive layer 23, and after peeling, the concealed information entry portion 1b is covered with the transparent adhesive layer 23 and the ultraviolet curable resin layer 22. It becomes. Since both the ultraviolet curable resin layer 22 and the transparent adhesive layer 23 are transparent, it is possible to read the information entered in the concealment information entry part 1b. And since the concealment information entry part 1b is covered with the cured ultraviolet curable resin layer 22, it cannot be written again. Furthermore, since the transparent adhesive layer 23 is also covered with the ultraviolet curable resin layer 22, it cannot be re-adhered.

  Here, in order to surely peel between the ultraviolet curable resin layer 22 and the release agent layer 21 at the time of peeling, the peel strength between the release agent layer 21 and the ultraviolet curable resin layer 22 is set to be the same as that of the transparent adhesive layer 23 and the ultraviolet ray. What is necessary is just to adjust so that it may become lower than the peeling strength with the cured resin layer 22, and the peeling strength with the transparent adhesive layer 23 and a base sheet (concealment information entry paper piece). If the pressure-sensitive adhesive layer 22 is formed of a general pressure-sensitive adhesive used in this type of postcard, this peel strength relationship is obtained due to the presence of the release agent layer according to the present invention.

  In differentiating the peel strength between the layers, for example, if a release agent containing a cationic polymerization ultraviolet curable silicone as a main component is used as the release agent, the adhesion can be achieved by adjusting the blend ratio of the silicone composition in the release agent. It is possible to adjust the strength (peel strength). By adopting this method, it is possible to easily and accurately adjust the adhesive strength (peel strength) to the ultraviolet curable resin layer.

  The above form is a form in which the information concealment sheet piece and the information entry sheet piece are connected to the left and right across the folding line. For example, as shown in FIGS. You can also. Further, as shown in FIGS. 8 and 9, an address information entry unit 2a may be provided on the surface 1A of the information entry sheet piece 1, and a background pattern may be printed on the surface 2A of the information concealment sheet piece 2.

  INDUSTRIAL APPLICABILITY The present invention can be used for applications where it is necessary to read information again after concealing information described on a sheet-like material, such as a concealed postcard, as well as a concealed postcard.

It is a figure which shows the surface side before use of the concealment type postcard X1 of this invention. It is a figure which shows the back surface side before use of concealment type postcard X1 of this invention. It is the III-III arrow line view of FIG. It is a perspective view which shows the surface side at the time of information concealment of the concealment type postcard X1 of this invention. It is a VV arrow line view of FIG. It is a figure which shows the state after information concealment paper piece peeling of the concealment type postcard X1 of this invention. It is a VII-VII arrow line view of FIG. It is a figure which shows the surface side of other form X2 of the concealment type postcard of this invention. It is a figure which shows the back surface side of other form X2 of the concealment type postcard of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Information entry paper piece, 2 ... Information concealment paper piece, 3 ... Fold line (perforation line), 4 ... Release paper, 1A ... Information entry paper piece surface, 1B ... Information entry paper piece back surface, 2A ... Information concealment paper piece Front surface, 2a ... address information description part, 2B ... information concealment paper half back, 2b ... concealment information entry part, 12 ... base paper layer, 21 ... release agent layer, 22 ... UV curable resin layer, 23 ... transparent adhesive layer, M ... tint block printing, X1, X2 ... concealed postcard.

Claims (3)

Having an information entry sheet piece and a concealment sheet piece connected via a folding line;
The information concealment sheet, wherein the concealment sheet piece has a layer structure in which a base paper layer, a release agent layer, a transparent ultraviolet curable resin layer, and a transparent adhesive layer are laminated in this order.   The information hiding sheet according to claim 1, wherein the release agent layer is mainly composed of a cationic polymerization ultraviolet curable silicone release agent.   The information hiding sheet according to claim 1, wherein a sealing layer is provided between the base paper layer and the release agent layer.

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