JP2008248435A - Plastic film substrate embedded paper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide paper which can prevent the wrinkling and waving of a sheet of a plastic film substrate or a paper layer, after embedded with the sheet. <P>SOLUTION: The paper formed by setting the sheet of the plastic film substrate on the surface of a first wet paper formed on a wire cloth and then putting a second wet paper formed on another wire cloth. In the combination paper, the critical length value measured by the Clark stiffness test method (JIS P 8143) of plastic film in the direction parallel to the CD direction of the first wet paper, when set on the first wet paper, is ≥187 mm. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a paper made by making a plastic film substrate such as a non-contact type IC tag inlet into paper.

An IC tag inlet has an IC chip and an antenna installed on a substrate such as a plastic film, and information can be read and written by a dedicated reader / writer. Utilizing this IC tag inlet will facilitate the management of logistics, books, medical care, etc., so the use of IC tag inlets is expected to increase in the future.
IC tag inlets are not only used on their own, but are also used in combination with mounts and films to record visual information (such as product names) and barcodes, and to protect IC tag inlets. There are many.

Conventionally, as a technology for combining IC tag inlet and paper, there is a method of inserting IC tag inlet between paper and pasting it with adhesive or adhesive, but the productivity is low and the cost of adhesive is said to be There's a problem.
Therefore, a technology to make a narrow plastic film with an IC tag inlet pasted between paper layers in the paper making process (see Patent Document 1), or a technology to make an IC tag inlet while forming a paper layer in the paper making process (See Patent Documents 2 and 3).

JP 2004-139405 A JP 2002-298118 A JP 2005-350823 A

However, in the case of conventional paper-making paper, after inserting the IC tag inlet at the position where the wet paper formed by different paper-making nets is put together, it is applied to the base material film of the IC tag inlet that is paper-made after drying. There is a problem that wrinkles occur and the paper layer of the resulting paper is undulated.
FIG. 3 is a schematic diagram showing the appearance of a papermaking sheet with such undulations, and a plurality of wrinkles extend along the MD direction (papermaking direction) L of the wet paper.

  The cause of this is not clear, but the following can be considered. First, since plastic sheets such as IC tag inlets do not allow water or air to pass through, they prevent dehydration with a wire suction box or press roll. There is a difference. Furthermore, since the movement of water vapor is hindered in the sheet insertion part even in the drying process, drying in this part is delayed, and the moisture difference further increases between the sheet insertion part and the other parts. It is considered that wrinkles occur in the sheet due to the moisture difference depending on the position of the paper layer, and the influence of heat during shrinkage and drying of the paper.

  Therefore, the present invention has an object of providing a papermaking paper that can prevent the occurrence of wrinkles or undulations in the plastic sheet or paper layer after the papermaking of the plastic sheet between the two wet paper webs. .

As a result of intensive studies, the inventors have found that when a sheet of a plastic base material having high rigidity is used, wrinkles are less likely to occur in the plastic sheet after papermaking.
Accordingly, the paper made of the present invention is a second paper formed on another paper mesh after a sheet of plastic film base material is placed on the surface of the first wet paper formed on the paper mesh. A method for testing Clark stiffness of the sheet in a direction parallel to the CD direction of the first wet paper when the paper is placed on the first wet paper. The critical length value according to JIS P 8143) is 187 mm or more.

  In the sheet, the length of each wet paper in the MD direction is preferably 100 mm or less, and the width of each wet paper in the CD direction is preferably 50 mm or less. Instead of the sheet, an IC chip is formed on the sheet. And an IC tag inlet provided with an antenna is preferably incorporated.

  According to the present invention, it is possible to prevent wrinkles and undulations from occurring in a plastic sheet or paper layer after the plastic sheet is sandwiched between two wet papers.

<Engraved paper>
A papermaking sheet according to an embodiment of the present invention was formed on another papermaking mesh after a plastic film base sheet was placed on the surface of the first wet paper formed on the papermaking net. Made by combining the second wet paper.
FIG. 1 shows a cross section perpendicular to the plane of the paper. A sheet (IC tag inlet) 2 of a flat plastic film base material is incorporated in the paper layer 1. The paper 1 is made by combining two paper layers A and B (described later) and dried. The paper layers A and B may be the same paper stock or different paper stocks. .

The papermaking paper of the present invention can be produced by a paper machine capable of making two or more layers of wet paper (multilayer papermaking). The plastic film sheet to be inserted is placed on one wet paper in at least one place of the paper making unit of the multi-layer paper machine, and then the other wet paper is made. Each wet paper web can be formed using at least one selected from a circular net, a long net, an inclined wire, and the like.
The paper-making paper of the present invention may be produced using a paper machine capable of making three or more layers of wet paper, and in this case, a plastic film between any two adjacent wet papers. The base sheet is engraved.
Moreover, it can be used as a label by coating an adhesive layer on the surface of the resulting paper. Further, by providing a coating layer on the surface, various recording aptitudes such as offset printing aptitude, thermal transfer recording aptitude, ink jet recording aptitude, and thermal recording aptitude can be imparted.

<Paper layer>
The material of the pulp used for the paper layer (wet paper) is not particularly limited, and LBKP, NBKP, mechanical pulp, and the like can be used. Also, the beating conditions are not limited.
The pulp used to form each paper layer may be of the same material and freeness, or may be different.
As will be described later, the dewaterability of wet paper is important to prevent waviness after engraving, but the effect of pulp material and beating degree on dewaterability is less than that of plastic sheets. Therefore, the pulp material and the beating degree can be appropriately selected according to the target paper quality.

  Furthermore, in the present invention, a filler and a sizing agent can be added to the paper as necessary. Although the kind of filler is not specifically limited, For example, calcium carbonate, talc, titanium oxide, kaolin, etc. can be used. Similarly, the sizing agent is not particularly limited, and examples thereof include rosin type, alkyl ketene dimer, styrene type, styrene-acrylic type, and alkenyl succinic acid type. As additives, fluorescent dyes, colorants, PH preparation agents, sulfuric acid bands, yield improvers, and the like can be used as appropriate in the stock.

Place a sheet of plastic film base on the surface of the wet paper, put another wet paper on top of it, dehydrate it with a wire suction box and press part, etc. It can be dried by applying heat of about 70 to 150 ° C. by the drying method.
Moreover, a normal size press can also be performed with respect to the obtained papermaking paper layer. Although the kind of chemical | medical agent used for a size press is not specifically limited, As an example, starch, oxidized starch, cationized starch, phosphate esterified starch, polyvinyl alcohol, carboxymethylcellulose, etc. can be mention | raise | lifted.

<Plastic film base sheet>
In the present invention, the material of the sheet of the plastic film substrate to be formed in the paper layer is not particularly limited, and for example, polyethylene terephthalate, polyethylene naphthalate, polypropylene, or the like can be used.

(Clark stiffness of plastic film base sheet)
In the present invention, when placed on the first wet paper, the value of the critical length according to the Clark stiffness test method (JIS P 8143) of the plastic film in the direction parallel to the CD direction of the first wet paper is It is necessary to be 187 mm or more.

According to the study by the present inventors, it has been found that the wrinkles extend along the MD direction of the paper on which the sheet of the plastic film substrate is formed. The cause is considered to be that the paper shrinks greatly in the CD direction in the wet paper drying process, so that if the rigidity of the sheet is low, the sheet shrinks and undulates in the CD direction, and wrinkles extend in the MD direction.
For this reason, it is considered that the shrinkage of the paper (and the sheet of the plastic film substrate) in the CD direction can be reduced by increasing the rigidity of the sheet corresponding to the CD direction of the paper layer.

If the critical length is less than 187 mm, the rigidity is lowered, and the sheet of the plastic film base material is deformed by the shrinkage or heat of the paper at the time of paper making, and wrinkles are generated on the paper.
The critical length described above is preferably less than 276 mm. When the critical length is 276 mm or more, the rigidity of the plastic film base sheet becomes too high, so the paper layer breaks through the inserted sheet, especially when the paper layer strength is weak, such as wet paper during drying. May be. Also, such a high-stiffness plastic film is usually thick and the paper thickness difference between the sheet insertion part and the non-insertion part of the paper layer is large, so that the appearance of the resulting paper is likely to deteriorate. is there.

(Dimensions of plastic film base sheet)
In the sheet of the plastic film base material, the length of each wet paper in the MD direction is preferably 100 mm or less, and the width of each wet paper in the CD direction is preferably 50 mm or less. The reason for this is thought to be that dehydration during papermaking proceeds as follows.

  First, when a plastic film base sheet is inserted between the wet papers, the inserted sheet prevents the wet paper from being dehydrated in the wire suction box, and the paper layer in the sheet insertion part has more water than the paper layer in the non-insertion part. . For this reason, in the press roll, the paper layer of the sheet insertion portion is easily crushed. And it is thought that dehydration of the paper layer in the wire suction box is performed by moving the water so as to go around in the CD direction of the wet paper while avoiding the inserted sheet. Therefore, the dewaterability tends to decrease as the width of the sheet increases. As a result of the study by the present inventors, when the width of the sheet to be inserted becomes larger than 50 mm, it becomes difficult to suppress the breakage of the paper layer in the press part. Since suppressing the breakage of the paper layer also leads to suppression of wrinkles in the drying process after the sheet is inserted, the sheet width in the CD direction of each wet paper is preferably 50 mm or less.

  In the press part which is the next process, most of the water squeezed by the press roll moves backward in the paper layer. Further, in the paper layer in the sheet insertion portion, the amount of water moving backward increases cumulatively as the pressing process proceeds. Furthermore, the paper layer in the sheet insertion portion has a long sheet length in the MD direction of each wet paper in addition to the large amount of water squeezed by the press roll due to insufficient dehydration in the wire suction box as described above. The cumulative amount of water that moves backward increases. Due to these combined actions, the longer the sheet length in the MD direction of each wet paper, the more easily the paper layer is crushed. Therefore, the sheet length in the MD direction of each wet paper is desirably 100 mm or less.

  Although the detailed cause is not understood about the mechanism of the generation | occurrence | production of the sheet | seat of a plastic film base material, the water | moisture content of the paper layer of a sheet insertion part is considered to be one of the causes. According to the study by the present inventors, the size of the ridge increases as the moisture content of the paper layer in the sheet insertion portion increases.

<IC tag inlet>
In the paper sheet of the present invention, instead of the sheet of the plastic film substrate, an IC tag inlet provided with an IC chip and an antenna may be formed on the sheet.
If the clerk stiffness of the sheet is specified in the above range, the rigidity of the IC tag inlet provided with the IC chip and the antenna on the sheet is considered not to be greatly changed from that of the single sheet of the plastic film base. The occurrence of wrinkles can be prevented in the same manner as when a film base sheet is engraved.

  As the antenna of the IC tag inlet, an electromagnetic induction type in which a conducting wire is wound in a coil shape to enable wireless communication, or a radio wave type in which a pole-shaped antenna is connected to an IC chip can be used.

  The IC tag inlet can be manufactured, for example, as follows. First, after depositing a metal such as aluminum on a roll-shaped film substrate, an antenna pattern is formed by an etching process. As another method for creating an antenna, a conductive paste to be an antenna pattern can be printed on a film. After the antenna pattern is created, an inlet can be obtained by bonding an IC chip on the film with an adhesive or the like.

<Example>
EXAMPLES Hereinafter, although an Example demonstrates this invention further in full detail, this invention is not limited by these.

(Preparation of paper material used for paper layer)
To 100 parts by mass of NBKP having a freeness of 600 ml, 0.1 part by mass of alkyl ketene dimer, 0.2 part by mass of cationized starch, and 0.2 part by mass of polyamide / epichlorohydrin were added to obtain a paper stock.

(Measurement of critical length with Clark stiffness tester for plastic film (JIS P 8143))
Measurements were made in the direction parallel to the CD direction of the paper.
The measurement piece had a width of 20 mm, and the length was cut from 75 mm to 300 mm by a measurement sample.

(Incorporation)
Using a long net / tilted combination paper machine shown in FIG. 2, a plastic sheet was made between two wet papers. Specifically, with respect Fourdrinier wire a on the formed wet paper A (basis weight 100 g / m ²⁾ in FIG. 2, it is formed with inclined wire b wet paper B (basis weight 100 g / m ²⁾ is It was installed at the position in front of the sheets to be combined. After wetting the wet papers A and B, the whole is treated with the press roll f at a linear pressure of 6.28 × 10 ⁵ Pa / cm (6.4 kg / cm), and further with the press roll g, the linear pressure is 3.24 × 10 ⁶ Pa / cm. It was dehydrated at cm (33 kg / cm), dried with several cylinder dryers h of 110 to 90 degrees, and wound on reel I as a papermaking paper.

A PET film (sheet of a plastic film substrate) having a thickness of 100 μm and a critical length of 187 mm was cut into a size of 50 mm in width and 100 mm in length so that the direction in which the critical length was measured was the short side. The cut sheet was placed on the surface of the wet paper A such that the long side of the cut sheet was parallel to the MD direction of the wet paper A.
When the paper made by cutting after reel I was visually observed, no wrinkles occurred, and the surface was smooth and had a good appearance.

Wrapped paper was produced in exactly the same manner as in Example 1, except that the plastic film base sheet was changed to a PET film having a thickness of 175 μm and a critical length of 276 mm.
When the obtained paper was visually observed, no wrinkles were generated, but a difference in thickness (step) was generated in the paper layer between the sheet insertion portion and the non-insertion portion, and the surface appearance was slightly inferior.

[Comparative Example 1]
Except for changing to a PET film having a thickness of 78 μm and a critical length of 160 mm as a plastic film base sheet, the paper was manufactured in the same manner as in Example 1. The paper was visually observed. A large number of large wrinkles extending in the paper making direction were generated on the sheet, and the paper layer was wavy.

[Comparative Example 2]
As a sheet of a plastic film substrate, the PET film used in Example 1 was cut into a size of 50 mm in width and 120 mm in length so that the direction in which the critical length was measured was the short side. The cut sheet was placed on the surface of the wet paper A such that the long side of the cut sheet was parallel to the MD direction of the wet paper A.
When each step before winding on reel I was visually observed, the paper layer in the inserted portion of the plastic sheet was crushed by the press part, and the engraved plastic sheet was exposed.

The obtained results are shown in Table 1.

As is apparent from Table 1, the paper made in Example 1 had a good appearance with no breakage of the paper layer in the film insertion portion, wrinkles of the paper layer, and undulations. In the case of Example 2, the paper layer was not crushed, wrinkled or waved as in Example 1, but the surface was uneven due to the thickness of the film.
In the case of Comparative Example 1, wrinkles along the MD direction occurred on the film, so wrinkles occurred on the paper layer. In the case of Comparative Example 2, the paper layer was crushed during the pressing process, and the paper-making paper was not completed.

It is a figure which shows the cross section of a direction perpendicular | vertical to the plane of a papermaking paper. It is a figure which shows the multilayer paper machine used for the papermaking. It is a schematic diagram of the conventional plastic sheet | seat in which the wrinkle entered after making.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Paper layer 2 Sheet | seat of plastic film base material A, B Wet paper a Long net wire b Inclined wire c Stock inlet d Foil e Wire suction box f Press g Press h Cylinder dryer
i reel

Claims (3)

After placing a sheet of plastic film base material on the surface of the first wet paper formed on the paper net, the paper made by combining the second wet paper formed on another paper web The critical length value according to the Clark stiffness test method (JIS P 8143) of the sheet in a direction parallel to the CD direction of the first wet paper when the paper is placed on the first wet paper. Wrapping paper characterized by being 187mm or more. 2. The paper-making paper according to claim 1, wherein a length of each wet paper in the MD direction is 100 mm or less and a width of each wet paper in the CD direction is 50 mm or less. The paper-making paper according to claim 1 or 2, wherein an IC tag inlet provided with an IC chip and an antenna is formed on the sheet instead of the sheet.

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