JP2009174991A - Pressure measuring sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-sensitivity pressure measuring sheet into a roll shape, capable of carrying out measurement at ultra low pressure which permits prevention of fracture of a microcapsule at that part, without generating creases when it is rolled. <P>SOLUTION: A pressure measuring sheet in a roll shape consists of a pressure measuring sheet which has a microcapsule, containing at least an electron donor colorless dye precursor and is wound around a winding core, and includes a first spacer and a second spacer, wherein the thickness difference (G1-G2) between the average thickness (G1) of the first spacer the average thickness (G2) of the second spacer is 0.15 mm or smaller in absolute value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a roll form in which a pressure measurement sheet having microcapsules containing at least an electron-donating colorless dye precursor used for measuring and recording a pressure distribution at a contact surface and a pressurized portion is wound around a winding core. This relates to a pressure measurement sheet.

Conventionally, pressure measurement sheets have been developed to accurately measure the balance, distribution, and size of the pressure applied between contact surfaces (contact pressure). For example, “Prescale” (trade name) from FUJIFILM Corporation. Is commercially available. This pressure measurement sheet is obtained by forming an electron-accepting compound (hereinafter, referred to as a color former) on a support having a color former layer containing a microencapsulated electron-donating colorless dye precursor (hereinafter sometimes referred to as “color former”). Overlapping the developer layer containing the developer (sometimes called "developer"), the microcapsule is destroyed by applying pressure, the color former in the microcapsule is brought into contact with the developer, and color is developed by a chemical reaction. It is something to be made.
In addition, recently, attempts have been made to make it possible to perform measurement at an extremely low pressure and to perform pressure measurement with an extremely small contact area (see Patent Document 1).

Such a pressure measurement sheet is usually distributed in the form of a roll wound around a winding core. At that time, as shown in FIG. 1A, spacers 4 and 4 are respectively formed in strips along the length direction of the pressure measurement sheet at both ends in the width direction of the surface of the pressure measurement sheet 1 having the microcapsules. ing. Accordingly, the pressure measurement sheet can be wound with a space therebetween, and the pressure measurement sheets can be prevented from coming into contact with each other at the time of winding and use, and the microcapsules can be prevented from being damaged.
However, when the pressure measurement sheet provided with the spacer is wound, as shown in FIG. 1C, if there is a difference in thickness (G1-G2) between the spacers at both ends of the sheet, the pressure measurement sheet is wound while being wound. There is a problem that winding wrinkles are generated, the microcapsules existing in the portion are broken, and the pressure cannot be measured.

  Therefore, it is desirable to provide a highly sensitive pressure measurement sheet in the form of a roll that can be measured at an ultra-low pressure that does not cause wrinkling when the pressure measurement sheet is wound and can prevent microcapsules from being broken at that portion. The current situation is rare.

JP 2000-32156 A

  An object of the present invention is to solve the conventional problems and achieve the following objects. That is, the present invention is a highly sensitive pressure measurement in a roll form that can be measured at an ultra-low pressure that does not cause wrinkles when the pressure measurement sheet is wound and can prevent microcapsules from being broken at that portion. The purpose is to provide a sheet.

Means for solving the above problems are as follows. That is,
<1> A pressure measurement sheet in the form of a roll formed by winding a pressure measurement sheet having microcapsules containing at least an electron donating colorless dye precursor around a winding core,
A first spacer and a second spacer along the length direction of the pressure measurement sheet at both ends in the width direction of the surface having the microcapsules of the pressure measurement sheet;
A roll having a thickness difference (G1-G2) between an average thickness (G1) of the first spacer and an average thickness (G2) of the second spacer of 0.15 mm or less in absolute value It is a pressure measurement sheet of a form.
<2> The roll-type pressure measurement sheet according to <1>, wherein the thickness difference (G1-G2) is 0.10 mm or less in absolute value.
<3> The roll-type pressure measurement sheet according to any one of <1> to <2>, wherein a material of the spacer is any one of a rubber foam and an elastic foam.
<4> The roll-type pressure measurement sheet according to any one of <1> to <3>, wherein flanges larger than a cross-sectional diameter of the roll-type pressure measurement sheet are respectively provided at both ends of the roll-type pressure measurement sheet. It is.
<5> The pressure measurement sheet according to <4>, wherein the flange has a polygonal shape of 4 or more and 12 or less.
<6> The pressure measurement sheet in a roll form according to any one of <4> to <5>, wherein the flange is made of plastic.

  According to the present invention, conventional problems can be solved, and the pressure measurement sheet can be measured at an ultra-low pressure without causing wrinkles when the pressure measurement sheet is wound and preventing the microcapsule from being broken at that portion. It is possible to provide a highly sensitive pressure measurement sheet in the form of a roll.

  The pressure measurement sheet of the present invention is in the form of a roll formed by winding a pressure measurement sheet having a microcapsule containing at least an electron-donating colorless dye precursor around a winding core. It has a flange, a spacer, and other members as necessary.

-Spacer-
As shown in FIG. 1A, the first spacer 4 and the second spacer 4 are respectively provided at both ends in the width direction of the surface having the microcapsules of the pressure measurement sheet 1 of the present invention along the length direction of the pressure measurement sheet. A spacer 4 is formed. Accordingly, the pressure measurement sheet can be wound with a space therebetween, and the microcapsules can be prevented from being damaged due to the pressure measurement sheets being in contact with each other during winding and use.

In the present invention, the thickness difference (G1-G2) between the average thickness (G1) of the first spacer and the average thickness (G2) of the second spacer is 0.15 mm or less in absolute value, The absolute value is preferably 0.10 mm or less, particularly preferably 0 mm (there is no difference between G1 and G2; see FIG. 1B). If the thickness difference exceeds 0.15 mm, the roll-shaped pressure measurement sheet (product) may be wrinkled during winding.
Here, as a method for measuring the spacer thickness, a spacer (100 mm length) to be measured is left still on the measurement stage. At this time, the measurement stage is larger than the spacer. A metal plate (made of stainless steel, thickness 0.5 mm) having the same width as the spacer to be measured is gently placed, and the central part is measured with a thickness measurement gauge (dial gauge, manufactured by Mitutoyo Corporation). The measurement was performed 5 times, and the average value was defined as the average thickness of the spacer.

The material of the spacer is not particularly limited and can be appropriately selected according to the purpose. However, the pressure measuring sheet can be reduced in weight by being either a rubber foam or an elastic foam. To preferred. Examples of the rubber foam include natural rubber, isoprene rubber, styrene rubber, nitrile rubber, butadiene rubber, chloroprene rubber, and urethane rubber. Examples of the elastic foam include polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polyvinyl acetate.
The thickness of the spacer is preferably 3 mm to 15 mm.
There is no restriction | limiting in particular as a method of providing a spacer on the said pressure measurement sheet | seat, According to the objective, it can select suitably, For example, the method of sticking with a double-sided tape, the method of sticking with an adhesive agent, etc. are mentioned.

−Flange−
The pressure measurement sheet of the present invention is in the form of a roll formed by winding a pressure measurement sheet having microcapsules containing at least a coloring agent around a winding core 3 having flanges 2 and 2 at both ends as shown in FIG. There is a gap Z between the pressure measurement sheet 10 in the roll form and the flange 3 (see FIG. 3). The gap Z may not be present.
In this case, the gap Z between the pressure measurement sheet 10 in the roll form and the flange 3 is preferably the same length at both ends of the pressure measurement sheet in the roll form, and the length of the gap Z is 2.5 mm. The above is preferable, 5 mm or more is more preferable, and 15 mm or more is still more preferable.
Thus, by providing a flange via the gap Z at both ends of the pressure measurement sheet 10 in the form of a roll, it is possible to prevent destruction of the microcapsules during transportation and storage. That is, when the roll-shaped pressure-preventing sheet 10 of the present invention shown in FIG. 4 is placed in a cardboard box and transported, the flange tilts when it receives an impact from the left as shown in FIG. However, since there is a gap Z between the flange and the pressure measurement sheet 10 in the form of a roll, the shock is absorbed by the gap Z, the impact is not transmitted to the pressure measurement sheet, and the microcapsules are not broken.

As described above, the flanges are attached to both ends of a winding core having a predetermined length in order to form a gap at both ends of the pressure measurement sheet in the form of a roll.
There is no restriction | limiting in particular about the magnitude | size, thickness, mass, shape, material, etc. of the said flange, According to the objective, it can select suitably.
The size (diameter or diagonal line) of the flange is larger than the diameter of the end face of the pressure measurement sheet in roll form, and the product is directly subjected to force when the pressure measurement sheet (product) in roll form is placed. It is preferable from the point of not.
The thickness of the flange differs depending on the material and cannot be defined unconditionally. For example, in the case of a plastic flange, 3 mm to 20 mm is preferable.
The mass of the flange varies depending on the material and cannot be defined unconditionally. For example, in the case of a plastic flange, 10 g to 100 g is preferable.
The shape of the flange is preferably a polygon of 4 or more and 12 or less from the viewpoint of product handling, and more preferably a 6-8 octagon.
Examples of the material of the flange include plastic, paper, wood, metal, and the like, but they are lightweight and plastic is particularly preferable for use in a clean room. Examples of the plastic include polypropylene (PP), polyethylene (PE), and polyethylene terephthalate (PET). Among these, a polypropylene with a low anisotropy in which the side surface portion of the flange has strength at any angle is particularly preferable, and examples thereof include Plapearl (manufactured by Takagi Sangyo Co., Ltd.).

-Roll core-
As described above, the winding core is not particularly limited in size, shape, material, etc., except that flanges are attached to both ends, and can be appropriately selected according to the purpose.
The size of the winding core differs depending on the material and cannot be defined unconditionally. For example, in the case of a paper winding core, a diameter of 50 mm to 105 mm is preferable.
Examples of the material of the winding core include plastic, paper, wood, metal and the like. Among these, paper is particularly preferable. Examples of the paper include paper tube base paper and resin-impregnated paper.
The method of attaching the flange to the winding core is not particularly limited and may be appropriately selected depending on the purpose. Examples thereof include a method of fitting with another bush flange or bonding with an adhesive. .

-Pressure measurement sheet-
The pressure measuring sheet is not particularly limited as long as it has microcapsules containing at least an electron-donating colorless dye precursor (color former), and can be appropriately selected according to the purpose. For example, a color former and a solvent In which a microcapsule encapsulating a color developer and a developer that develops color by reacting with the color former are provided (preferably coated) on a single base material or on a separate base material, etc. Can be mentioned.
In the case of a so-called mono-sheet type in which the microcapsules and the developer are provided on a single base material, the pressure measurement sheet includes a base material such as a sheet or a film, and the base material on the base material. It comprises a developer-containing developer layer and a microcapsule-containing color developer layer, which are provided in this order from the material side, and pressurizes them by sandwiching them alone at a site where pressure or pressure distribution is to be measured.
In the case of a so-called two-sheet type in which the microcapsules and the developer are provided on separate substrates, the pressure measurement sheet is not contained in the developer on the substrate such as a sheet or a film. A surface comprising a material A having a developer layer and a material B having a color-encapsulating layer containing a microcapsule on a substrate such as a sheet or a film, on which the microcapsules of the material B are provided (color development) The surface of the agent layer) and the surface of the material A on which the electron accepting compound is provided (the surface of the developer layer) are overlapped with each other, and the pressure is applied by sandwiching the pressure or the pressure distribution in the site where the pressure distribution is to be measured.
In addition, the pressure measurement sheet is provided from the viewpoint of storage stability and handleability by coating the microcapsules enclosing the electron-donating colorless dye precursor and the electron-accepting compound on separate substrates. More preferably, it is configured as a two-sheet type.

The roll-type pressure measurement sheet of the present invention is packed in a cardboard box 20 as shown in FIG. 5, and is transported and stored.
In FIG. 5, reference numeral 11 denotes a partition plate, which is provided to prevent the pressure measurement sheet 10 in a roll form and the pressure measurement sheet 12 in another roll form from contacting each other.
In FIG. 5, reference numeral 13 denotes a buffer material. By using the pressure measurement sheet in the form of a roll according to the present invention, breakage of the microcapsules can be prevented without using the buffer material, even if a buffer material is used. A small amount is fine.
There is no restriction | limiting in particular as said cardboard box, According to the objective, it can select suitably, For example, a polypropylene cardboard is preferable.
Also, if the corrugated side corrugations (corrugations) of the corrugated cardboard box are parallel to the bottom surface, the repulsive force is small compared to ordinary corrugated corrugated cardboard, and it is easy to fold. Further, it is preferable from the point of being able to prevent damage when taking out the roll-type pressure measurement sheet from the cardboard during packaging.

  The pressure measurement sheet in the form of a roll according to the present invention can accurately measure the balance, distribution, and size of pressure, such as automobiles, construction machines, motorcycles, ships, aircraft, electronic equipment, roll nip pressure, fluid pressure. It can be applied to various fields such as medical treatment. Especially as an ultra-low pressure measurement sheet used in a clean room, confirm the uniformity of the connecting surface of the semiconductor chip and lead wire, confirm the uniformity of the squeegee pressure in the production of multilayer substrates, and mount components on the thick film substrate Confirming the parallelism of parts and contactability of connecting pins, confirmation of uniformity, balance, and pressure level of glass-to-glass bonding process in liquid crystal, plasma display and flat CRT cathode ray tube manufacturing , And the like.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

Example 1
On a polyethylene terephthalate (PET) film having a width of 450 mm and a thickness of 75 μm, the following color former layer forming coating solution and the following protective ear layer forming coating solution are sequentially applied without any gaps, and then dried to obtain a color former. An electron donating colorless dye sheet having a layer width of 400 mm and a protective ear layer width of 25 mm on one side (50 mm on both sides) was prepared.

-Coating solution for forming color former layer-
18 parts by mass of Compound A represented by the following structural formula as a color former was dissolved in 70 parts by mass of diarylethane to obtain Solution A. Further, 0.4 part by mass of an ethylenediamine butylene oxide adduct dissolved in 1 part by mass of methyl ethyl ketone was added to the stirring solution A to obtain a solution B. Furthermore, 2 parts by mass of a trimethylolpropane adduct of tolylene diisocyanate dissolved in 1 part by mass of methyl ethyl ketone was added to the solution B being stirred to obtain a solution C.
Next, the solution C was added to a solution obtained by dissolving 6 parts by mass of polyvinyl alcohol in 150 parts by mass of water, and emulsified and dispersed. 300 parts by mass of water was added to the emulsified liquid after emulsification and dispersion, and the mixture was heated to 70 ° C. with stirring, stirred for 1 hour and then cooled to prepare a microcapsule liquid containing microcapsules encapsulating the color former. The median diameter of the obtained microcapsules based on the volume standard was 20 μm. The median diameter was measured using a multisizer (manufactured by Coulter). The prepared microcapsule solution was used as a coating solution for forming a color former layer.

-Protective ear layer forming coating solution-
After mixing 75 parts by weight of water, 5 parts by weight of sodium polyacrylate, and 100 parts by weight of calcium carbonate and dispersing with a sand mill, the SBR latex is equivalent to 15 parts by weight of solid content, and 15 parts by weight of an aqueous solution of 1% by weight of carboxymethyl cellulose. Then, 1 part by mass of an aqueous solution of 25% by mass of sodium dodecylbenzenesulfonate was added and mixed, and water was further added to adjust the solid content concentration to 41.5% by mass to prepare a coating solution for forming a protective ear layer.

  The central part of the obtained sheet was cut into a width of 350 mm using a processing machine. The following double-sided tape is attached to both edge portions of the cut sheet, the following first and second spacers are attached, wound on a flanged core shown in FIG. 2, and the cross-sectional diameter of both ends is 170 mm and the mass is 800 g. A pressure measurement sheet in the form of a roll as shown in FIG. 3 was produced.

-First and second spacers-
Material: Neoprene foam rubber (manufactured by Tokiwa Rubber Co., Ltd.), width 15 mm, thickness of first and second spacers is 5.00 mm
In addition, the 1st and 2nd spacer thickness left the spacer (100 mm length) of a measuring object on the measurement stage. At this time, the measurement stage is larger than the spacer. A metal plate (stainless steel, thickness 0.5 mm) having the same width as the spacer to be measured was gently placed, and the central part was measured with a thickness measurement gauge (dial gauge, manufactured by Mitutoyo Corporation). The measurement was performed 5 times, and the average value was defined as the average thickness of the spacer.
-Double-sided tape-
Japanese paper + acrylic adhesive (manufactured by Sekisui Chemical Co., Ltd., double tack tape # 595), width 10 mm
-Roll core-
Made of paper, length 390mm
−Flange−
Material: Polypropylene (PP), Shape: Octagon, Size (Diagonal length): 210mm, Thickness: 5mm

(Example 2)
-Production of pressure measurement sheet-
In Example 1, except that the thickness of the first spacer is 5.05 mm and the thickness of the second spacer is 5.00 mm, the pressure measurement sheet in the roll form of Example 2 is the same as Example 1. Produced.

(Example 3)
-Production of pressure measurement sheet-
In Example 1, except that the thickness of the first spacer was 5.10 mm and the thickness of the second spacer was 5.00 mm, the pressure measurement sheet in the roll form of Example 3 was the same as Example 1. Produced.

Example 4
-Production of pressure measurement sheet-
In Example 1, except that the thickness of the first spacer was 5.15 mm and the thickness of the second spacer was 5.00 mm, the pressure measurement sheet in the roll form of Example 4 was the same as Example 1. Produced.

(Comparative Example 1)
-Production of pressure measurement sheet-
In Example 1, a pressure measurement sheet in the form of a roll of Comparative Example 1 was prepared in the same manner as in Example 1 except that the thickness of the first spacer was 5.20 mm and the thickness of the second spacer was 5.00 mm. Produced.

(Comparative Example 2)
-Production of pressure measurement sheet-
In Example 1, the pressure measurement sheet in the roll form of Comparative Example 2 is the same as Example 1 except that the thickness of the first spacer is 5.25 mm and the thickness of the second spacer is 5.00 mm. Produced.

<Evaluation of winding wrinkles>
When each pressure measurement sheet was wound around the core, whether or not wrinkles were generated on the sheet surface was evaluated according to the following criteria. The results are shown in Table 1.
〔Evaluation criteria〕
○: No generation of winding wrinkles was observed.
(Triangle | delta): Although there was no generation | occurrence | production of a wrinkle, the deformation | transformation of a film was recognized (actual use possible level).
X: Many generation | occurrence | production of winding wrinkles was recognized.

<Evaluation of capsule destruction>
Each pressure measurement sheet was wound around a winding core, and whether or not the capsule was broken was visually observed for the roll-shaped pressure measurement sheet. The results are shown in Table 1. Note that when the microcapsule is broken, the oil comes out from the capsule at that portion and becomes transparent to translucent.

  The pressure measurement sheet of the present invention can accurately measure the balance, distribution and size of pressure, such as automobiles, construction machines, motorcycles, ships, aircraft, electronic equipment, nip pressure of rolls, fluid pressure, medical care, etc. It can be applied to various fields.

FIG. 1A is a plan view showing a state in which a spacer is attached to the pressure measurement sheet of the present invention. FIG. 1B is a cross-sectional view taken along the line I-I in FIG. 1A and shows a case where the thickness difference (G1-G2) is zero. FIG. 1C is a cross-sectional view taken along the line I-I in FIG. 1A and shows a case where the thickness difference (G1-G2) is 0.25. FIG. 2 is a diagram showing an example of a flanged core used in the roll-type pressure measurement sheet of the present invention. FIG. 3 is a diagram showing an example of a pressure measurement sheet in the form of a roll according to the present invention. FIG. 4 is a diagram showing a pressure measurement sheet in the form of a roll according to the present invention and a state when the sheet receives an impact. FIG. 5 is a diagram showing how the pressure measurement sheet in the form of a roll according to the present invention is packed in a cardboard box.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pressure measurement sheet 2 Flange 3 Winding core 4 Spacer 10 Roll form pressure measurement sheet 20 Corrugated cardboard box

Claims (6)

A pressure measurement sheet in the form of a roll formed by winding a pressure measurement sheet having microcapsules containing at least an electron-donating colorless dye precursor around a winding core,
A first spacer and a second spacer along the length direction of the pressure measurement sheet at both ends in the width direction of the surface having the microcapsules of the pressure measurement sheet;
A roll having a thickness difference (G1-G2) between an average thickness (G1) of the first spacer and an average thickness (G2) of the second spacer of 0.15 mm or less in absolute value Form of pressure measurement sheet.   The roll-shaped pressure measurement sheet according to claim 1, wherein the thickness difference (G1-G2) is 0.10 mm or less in absolute value.   The roll-shaped pressure measurement sheet according to claim 1, wherein a material of the spacer is any one of a rubber foam and an elastic foam.   The roll-type pressure measurement sheet according to any one of claims 1 to 3, wherein flanges larger than a cross-sectional diameter of the roll-type pressure measurement sheet are respectively provided at both ends of the roll-type pressure measurement sheet.   The roll-shaped pressure measurement sheet according to claim 4, wherein the flange has a polygonal shape of 4 or more and 12 or less.   The roll-shaped pressure measurement sheet according to any one of claims 4 to 5, wherein a material of the flange is plastic.

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