JP2008248436A - Plastic sheet embedded paper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide embedded paper which is formed by embedding a plastic sheet such as a non-contact type IC tag inlet by the use of a multiplying paper machine and can prevent the wrinkling and waving of the plastic sheet and a paper layer. <P>SOLUTION: This paper 1 embedded with a plastic sheet 2 such as a non-contact type IC tag inlet by the use of a multiplying paper machine. In the paper 1, a non-stretched film is used as the plastic sheet and further defining the size of the plastic sheet. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a paper made by making a plastic sheet 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 in wire suction boxes and press rolls. There is a difference. Furthermore, since the movement of water vapor is hindered in the sheet insertion portion even in the drying process, drying in this portion is delayed, and the moisture difference further increases between the sheet insertion portion and the other portions. 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.

  Accordingly, the present invention provides a papermaking paper that can prevent the occurrence of wrinkles or undulations in a plastic sheet or paper layer after making a paper sheet between two wet paper sheets. Objective.

As a result of intensive studies, the inventors have found that when an unstretched film is used as a plastic sheet, it becomes difficult for wrinkles to occur in the plastic sheet after papermaking.
Accordingly, the papermaking paper of the present invention is characterized in that a plastic sheet is made using a multilayer papermaking machine, and the plastic sheet is an unstretched film.

In the plastic sheet, it is preferable that the length of each wet paper in the MD direction is 100 mm or less, and the width of each wet paper in the CD direction is 50 mm or less.
Instead of the plastic sheet, it is preferable that an IC tag inlet provided with an IC chip and an antenna is embedded on the plastic sheet.

  According to the present invention, it is possible to prevent wrinkles and undulations from being generated in a plastic sheet or paper layer after the plastic sheet is made using a multilayer paper machine.

<Engraved paper>
The papermaking according to the embodiment of the present invention is made by papering a plastic sheet using a multi-layer papermaking machine.
FIG. 1 shows a cross section perpendicular to the plane of the paper. A flat plastic sheet (IC tag inlet) 2 is formed in the paper layer 1. Wrapping paper 1 consists of two wet papers A and B (to be described later) that become paper layers after drying and dried. Paper layers A and B are different papers even if they are the same paper stock. It may be a fee.

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.
In addition, you may manufacture the papermaking paper of this invention using the paper machine which can make a wet paper of 3 layers or more, and in this case, it is made of plastic between any two adjacent wet paper webs. Sheets are drawn.
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 each paper layer 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 for the wet paper laminated to form the 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 each paper layer 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 plastic sheet 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., then use a normal drying method such as a cylinder dryer or Yankee dryer. Can be dried by applying a heat of about 70 to 150 ° C. to form a paper layer.
Moreover, normal size press can also be performed with respect to the obtained 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 sheet>
(Unstretched film)
In the present invention, it is necessary that the plastic sheet incorporated in the paper layer is made of an unstretched film.
Plastic film production methods include production methods that do not undergo stretching in the film production process, such as the melt casting method, melt extrusion method (T-die method), and calendar method, and the uniaxial stretching method and biaxial stretching method. There exists a manufacturing method by which a extending | stretching process is performed in a film manufacturing process. The unstretched film used in the present invention refers to a film that has been produced in the former production process and not subjected to a stretching treatment.
The uniaxial stretching method and the biaxial stretching method are uniaxial or biaxial in a state where the plastic film is heated to a temperature not lower than the softening point of the film and not higher than the melting point in order to impart functions such as mechanical strength to the plastic film. The film is stretched and heat-set. When such a stretched film is incorporated in the paper layer, the present inventors have found that large and deep wrinkles as shown in FIG. It became clear by the examination. This is considered to be because when the stretched film is reheated at a temperature equal to or higher than the softening point, the stretched film tends to return (shrink) to the state before stretching.

On the other hand, when the present inventors investigated by drawing the unstretched film in the paper layer, the film itself was gently wavy after drying, or the film had many fine and shallow wrinkles. It was found that these did not appear on the appearance of the paper.
The reason why such a difference occurs depending on the presence or absence of the stretching treatment is not clear, but when a force is applied in the direction in which the film softened by the drying heat in the papermaking process is contracted due to shrinkage of the paper, etc. It is conceivable that the axially stretched film resists shrinkage due to its mechanical strength, and is liable to generate large and deep wrinkles. In addition, as described above, when the biaxially stretched film is reheated, there is a force to shrink to the dimensions before stretching, so the degree of shrinkage increases as the paper shrinks, etc., and it may be prone to deep wrinkles. .
In particular, the shrinkage of the paper is larger in the CD direction than the MD direction of the wet paper, and the film also tends to shrink in this direction.

The non-stretched film used in the present invention is not limited in its production method as long as it is not stretched in the film production process. For example, a plastic produced by a production method such as a melt extrusion molding method or a solution casting method. Film can be used.
The material and composition of the unstretched film are not particularly limited, and for example, polypropylene (PP), triacetyl cellulose, or the like can be used.
Examples of unstretched films used in the present invention include unstretched polypropylene films (CPP) produced by the T-die method, triacetylcellulose films (TAC) produced by the solution casting method, and the like. It is not limited to.

The unstretched film may be a single layer or a multilayer, and each layer may be composed of films having different compositions.
The thickness of the unstretched film is not particularly limited, but is desirably 30 μm or more and 200 μm or less. If the thickness is less than 30 μm, the stiffness is weak and it may be difficult to handle the film in the process of papermaking. If the thickness is greater than 200μm, the difference in paper thickness between the part where the film is made and the part where the film is not made becomes too large. There is.

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

  First, when a plastic 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 portion has more water than the paper layer in the non-insertion portion. 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 wrap around the wet paper in the CD direction 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 is 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 wrinkle generation in the drying step after the plastic 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 of the wrinkle generation mechanism of the plastic sheet is not known, it is thought that one of the causes is that the moisture in the paper layer of the sheet insertion portion is high. 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 plastic sheet, an IC tag inlet provided with an IC chip and an antenna may be formed on the plastic sheet.
The wrinkles that enter the unstretched film in the drying process are gentler than those that enter the stretched film, and are not strong enough to deform the antenna provided on the film.

  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.

(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 (Plastic sheet of commercial unstretched PP film with a width of 50mm, a length of 100mm, and a thickness of 40μm) at the position just before the sheets are put together so that the long side of the sheet is parallel to the MD direction of wet paper A Installed on the surface of wet paper A.
After the paper sheets are sandwiched between the wet papers A and B, the whole is processed with a press roll f at a linear pressure of 6.28 × 10 ⁵ Pa / cm (6.4 kg / cm), and the press roll g Was dehydrated at a linear pressure of 3.24 × 10 ⁶ Pa / cm (33 kg / cm), dried with several cylinder dryers 110 to 90 degrees, and wound on reel I as paper-making paper.
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.
Further, when the paper layer of the paper to be engraved was peeled off and the internal plastic sheet was visually observed, many small shallow wrinkles were contained in the sheet.

Except for using a non-stretched film obtained by processing a TPX (polymethylpentene) resin into a film with an extruder (resin processing temperature 320 ° C.) instead of a non-stretched PP film as a plastic sheet, exactly the same as Example 1. In the same manner, a paper sheet was produced.
When the obtained paper was visually observed, no wrinkles were observed on its appearance. Further, when the paper layer of the paper to be engraved was peeled off and the internal plastic sheet was visually observed, the sheet was gently shrunk.

Implemented except that instead of the plastic sheet used in Example 1, a commercially available triacetyl cellulose film (TAC) plastic sheet manufactured by a solution casting method without stretching treatment was used. A paper sheet was produced in exactly the same manner as in Example 1.
When the obtained paper was visually observed, no wrinkles were observed and the appearance was good. Further, when the paper layer of the paper to be engraved was peeled off and the internal plastic sheet was visually observed, many small shallow wrinkles were contained in the sheet.

[Comparative Example 1]
A paper sheet was produced in exactly the same manner as in Example 1 except that a plastic sheet of a commercially available biaxially stretched PP film was used as the plastic sheet in place of that used in Example 1.
When the paper was visually observed, large wrinkles were generated on the sheet, and the paper layer was wavy.

[Comparative Example 2]
A paper sheet was produced in exactly the same manner as in Example 1 except that a commercially available biaxially stretched PET film was used instead of the plastic sheet used in Example 1.
When the paper was visually observed, large wrinkles were generated on the sheet, and the paper layer was wavy.

[Comparative Example 3]
A paper sheet was manufactured in exactly the same manner as in Example 1, except that a plastic sheet of a commercially available biaxially stretched PEN film was used instead of the plastic sheet used in Example 1.
When the paper was visually observed, large wrinkles were generated on the sheet, and the paper layer was wavy.

As is clear from the above results, no wrinkles were observed in the appearance of the papermaking in each example.
On the other hand, in each of the comparative examples using a biaxially stretched film as the plastic sheet, large and deep wrinkles occurred regardless of the thermal strength, and the appearance was inferior as the irregularities were seen from the top of the paper layer.

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

Explanation of symbols

1 Wrapping paper 2 Plastic sheet (unstretched film)
A, B Wet paper (paper layer)
a long wire b inclined wire c stock inlet d foil e wire suction box f press g press h cylinder dryer
i reel

Claims (3)

A papermaking machine in which a plastic sheet is made using a multi-layer papermaking machine, wherein the plastic sheet is an unstretched film. 2. The engraving according to claim 1, wherein a length of each wet paper in the MD direction of the plastic sheet is 100 mm or less and a width of each wet paper in the CD direction is 50 mm or less. paper. 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 plastic sheet instead of the plastic sheet.

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