JP2010259982A - Coating method for high viscosity solution - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating method which stably applies a high viscosity solution to a wet web or paper. <P>SOLUTION: In the coating method for a high viscosity solution a high viscosity solution having a viscosity of 1,000-2,500 mPa s at 30°C is injected in the form of a sector having an angle θ<SB>1</SB>(degree) at an injection pressure of 3.0-20.0 kPa and injected so that the surfaces of the sectors formed by the high viscosity solution are parallel to each other and intersect with the line width direction at an angle θ<SB>2</SB>(degree) from injection ports, having an orifice diameter of 0.5-1.1 mm and installed side by side at intervals of L<SB>2</SB>(mm) in the line width direction so as to be spaced from the wet web or paper by a distance L<SB>1</SB>(mm), to transporting wet web or paper and the length L<SB>3</SB>(mm) of an overlapped part of the high viscosity solution injected from the adjacent injection ports in high viscosity solution reached parts on the wet web or paper satisfies L<SB>3</SB>=2X-L<SB>2</SB>under conditions, 50≤L<SB>1</SB>≤250, 50≤L<SB>2</SB>≤120 mm, and 50≤θ<SB>1</SB>≤110, wherein X=L<SB>1</SB>tan(θ<SB>1</SB>/2)cos(θ<SB>2</SB>) and X≥3L<SB>2</SB>/4. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a coating method for a high-viscosity solution, and more particularly to a coating method for spraying and coating a high-viscosity solution on wet paper flowing on a line of a paper machine or paper flowing on a processing machine.

  Conventionally, additives such as a paper strength enhancer and a surfactant for wet paper flowing on a paper machine line or paper flowing on a processing machine in order to impart various properties to the wet paper or paper. Many devices and methods for applying these solutions have been proposed. Examples thereof include an apparatus or method for applying by roll transfer as shown in Patent Document 1 below, and an apparatus or method for applying by spray as shown in Patent Document 2 below.

  In order to enhance the effect of the additive, it is conceivable to increase the concentration of the additive in the solution. However, when the concentration in the solution increases, the additive such as a paper strength enhancer or a surfactant increases with the solution. There are many things that increase the viscosity.

JP 2006-007218 A Japanese Patent No. 3432819 Japanese Patent No. 2882881 JP 2007-169874 A Special table 2003-527237 gazette

However, the application of a high-viscosity solution of additive to wet paper or paper means that in the conventional application by roll transfer, the high-viscosity solution on the roll does not uniformly adhere to the wet paper or paper, resulting in uneven coating. However, it was not possible to carry out it suitably.
On the other hand, in the conventional application by spraying, if the viscosity of the solution is high, the high-viscosity solution does not smoothly pass through the spray nozzle, so that the high-viscosity solution cannot be stably sprayed, and uneven coating is also caused. There was a problem that it would occur.
Then, the main subject of this invention is providing the coating method of the high-viscosity solution which enabled stable application of the high-viscosity solution with respect to a wet paper or paper.

Next, means for solving the above problems and their effects will be described.
[Invention of Claim 1]
The wet paper or paper is separated from the wet paper by a distance L ₁ [mm] and is arranged in parallel in the line width direction at an interval L ₂ [mm], and is conveyed from an injection port having an orifice diameter of 0.5 to 1.1 mm. A high-viscosity solution having a viscosity of 1000 to 2500 mPa · s at 30 ° C. is jetted in a fan shape with an injection pressure of 3.0 to 20.0 kPa and an angle θ ₁ [degrees] on a wet paper or paper. A method of applying a viscous solution,
The high-viscosity solution is jetted so that the fan-shaped surfaces of the high-viscosity solution jetted from the jet nozzles are parallel to each other and intersect at an angle θ ₂ [degree] with respect to the line width direction,
The length L ₃ [mm] of the portion where the high-viscosity solution sprayed from the mutually adjacent spray ports wraps at the high-viscosity solution reaching portion of the wet paper is 50 ≦ L ₁ ≦ 250, 50 ≦ L ₂ ≦ 120. Satisfying the formula (1) under the condition of 50 ≦ θ ₁ ≦ 110,
A method for applying a high-viscosity solution.
L ₃ = 2X−L ₂ (1)
Here, X is a value that satisfies Equation (2) and Equation (3) simultaneously.
_{X = L 1 tan (θ 1} /2) cos (θ 2) ··· (2)
_{X ≧ 3L 2/4 ··· (} 3)

(Function and effect)
In general, when a solution such as a paper strength enhancer or a surfactant is applied to wet paper or paper by spray injection, a high-viscosity solution having a viscosity at 30 ° C. of 1000 mPa · s or more has a viscosity of the solution. It was too high to spray evenly. On the other hand, in the invention according to the present invention, the high-viscosity solution is injected from the injection port having an orifice diameter of 0.5 to 1.1 mm with an injection pressure of 3.0 to 20.0 kPa. Since the diameter of the particles ejected from the mouth becomes moderately coarse, the high viscosity solution is suitably fixed to the wet paper or paper.

In addition, the high-viscosity solution is ejected so that the fan-shaped surfaces of the high-viscosity solution ejected from each ejection port are parallel to each other and intersect at an angle θ ₂ [degrees] with respect to the line width direction, and The length L ₃ [mm] of the portion where the high-viscosity solution jetted from the mutually adjacent jetting ports wraps in the wet paper or the high-viscosity solution reaching portion of the paper is 50 ≦ L ₁ ≦ 250, 50 ≦ L _2. By applying so as to satisfy the formula (1) under the conditions of ≦ 120 and 50 ≦ θ ₁ ≦ 110, the high-viscosity solution can be uniformly applied in the width direction of the line.

In addition, the orifice diameter said here is calculated when water is injected by Formula (A).

[Invention of Claim 2]
The coating method of the high-viscosity solution according to claim 1, wherein the angle θ ₂ [degree] is 5 to 30 degrees.

(Function and effect)
In the coating method of the high viscosity solution according to the present invention, the high viscosity solution so that the fan shape of the high viscosity solution ejected from the ejection port intersects at an angle θ ₂ [degree] of 5 to 30 degrees with respect to the line width direction. It is preferable that it is comprised so that may be injected. If the angle θ ₂ [degrees] is more than 30 degrees, the coating area per each injection port becomes narrow, and the wrapping of the high-viscosity solution sprayed from the adjacent nozzles is reduced. There is a high possibility that general drying defects and wrinkles will occur, and as a result, suitable quality cannot be obtained. On the other hand, if the angle θ ₂ [degree] is less than 5 degrees, it overlaps with the particles applied from the adjacent nozzles, and the spraying is not uniform, resulting in uneven coating, resulting in partial drying defects and wrinkles. It is highly probable that the required quality will not be obtained.

  As described above, according to the present invention, it is possible to provide a method for applying a high-viscosity solution that can stably apply a high-viscosity solution to wet paper or paper.

It is the figure which showed typically an example of the double felt paper machine using the coating method of the high viscosity solution which concerns on this invention. It is a schematic diagram of the shower pipe used with the coating method of the high viscosity solution which concerns on this invention. FIG. 3 is a partially enlarged view of FIG. 2. FIG. 3 is a partially enlarged view corresponding to an XX arrow shown in FIG. 2. In the example of the double felt paper machine shown by FIG. 1, it is a schematic diagram which shows a mode that the high-viscosity aqueous solution is sprayed on the wet paper with the coating method of the high-viscosity solution which concerns on this invention.

Next, an embodiment of a method for applying a high-viscosity solution according to the present invention will be described with reference to an example of a method for producing a water-decomposable sheet using the double felt paper machine shown in FIG. In addition, the numerical value of the viscosity in the following is LVDVE115 No. made from BROOKFIELD. The numerical value obtained by measuring with 3 terminals is shown.
The paper stock supplied from the preparation device (not shown) is made into a wet paper W by making a paper with a wire part (not shown). The preparation device is a device that releases and beats raw materials such as pulp fibers, and a sizing agent, dryer release agent, dryer adhesive, dye, dry paper strength agent, wet paper strength agent, dispersant, etc. And an addition device for adding an additive, and is configured to adjust a paper stock made of a raw material having a predetermined concentration according to the characteristics of the obtained dried web W ′ as a finished paper stock.

  The paper furnish contains fibers such as pulp and rayon. The blending of the furnish can be the same as in normal paper manufacture. The pulp is bleached wood pulp such as softwood bleached kraft pulp (NBKP), hardwood bleached kraft pulp (LBKP), etc., and unbleached pulp, alkali-swelled mercerized pulp subjected to chemical treatment, chemical with spiral structure Cross-linked pulp can be used, and the same cellulosic fiber and biodegradable cotton fiber or regenerated cellulose fiber can be used. This pulp includes used paper raw materials such as high-quality paper and magazines. It is also possible to use fibers made of polylactic acid as biodegradable fibers. In addition, it is also possible to use chemical fibers such as polyvinyl alcohol fibers, other polyolefin fibers, and polyester fibers.

  As shown in FIG. 1, the wet paper W made by the wire part is placed on the bottom felt 11 and is sandwiched between the top felt 10 and the bottom felt 11, and a top roll 12 that is a press roll, It passes between the bottom roll 13 which is also a press roll, and is squeezed. Here, since the density of the wet paper W increases at the same time as the squeezing, the strength of the paper increases and the paper breakage decreases, the paper structure is densified, the paper texture is formed, and the wet paper W is Transferred onto the top felt 12.

  The top felt 10 and the bottom felt 11 are composed of known paper-making felts, for example, those obtained by needling and integrating a fiber web on both sides or one side of an endlessly woven base fabric, After joining the start end and the end of a base fabric woven in an end shape and processing it into an endless shape, it is possible to apply a fiber web that is integrated by needling on both sides or one side of the base fabric.

  Thereafter, the wet paper web W that has been squeezed is attached to the surface of the Yankee dryer 15 via the touch roll 16 while being placed on the top felt 10. Then, the wet paper W is heated and dried by the Yankee dryer 15, peeled off by the creping doctor 17, and proceeds to the next step.

  A cleaning doctor device 18 that scrapes off the fouling of the coating agent that has been heat-sealed on the surface of the Yankee dryer 15 is provided downstream of the creping doctor 17 with respect to the rotational direction of the Yankee dryer 15 and in front of the touch roll 16. Is provided.

  In the subsequent stage of the Yankee dryer 15 in the top felt 10, there are a high-pressure water washing shower 1 for washing the surface of the top felt 10 by spraying washing water, and a suction box 3 and a squeeze roll 4 for removing the washed water. Is provided. By providing these, when the wet paper W is squeezed between the top roll 12 and the bottom roll 13, chemicals and pulp short fibers contained in the wet paper W transferred to the surface of the top felt 10 are contained. Can be cleaned and removed.

  A hood 19 that covers the Yankee dryer 15 almost airtightly is provided around the Yankee dryer 15 so that air heated to a predetermined temperature is supplied into the hood 19. In other words, the wet paper W is heated and dried by the Yankee dryer 15 and is also dried by the heated air supplied into the hood 19.

  As shown in FIG. 1, a shower pipe 20 for applying an additive solution is provided on the Yankee dryer 15, which is a rear stage of the touch roll 16 and a front stage part of a hood 19. As shown in FIGS. 1 to 5, the shower pipe 20 is formed of a rod-like tube body, and is arranged so that the axis of the shower pipe 20 and the axis of the Yankee dryer 15 are parallel to each other.

  As shown in FIGS. 2 and 5, a nozzle 21 that is intermittently arranged along the extending direction of the shower pipe 20 is installed in the shower pipe 20 so as to protrude from the shower pipe 20. All the separation distances between the adjacent nozzles 21 are equal.

  Screws are cut at the base end side of the peripheral surface of the nozzle 21 and the attachment opening of the nozzle 21 in the shower pipe 20, and the nozzle 21 can be detached from the shower pipe 20.

  The nozzle 21 is a tubular body having a hollow inside, and has a square tip portion 22 whose side surface is an isosceles trapezoidal shape on the tip side. At the tip of the tip portion 22, an injection port 23 formed in an elongated elliptical shape is opened, and the injection port 23 communicates with the internal space of the nozzle 21. In addition, the shower pipe 20 is installed such that the injection port 23 faces the wet paper W on the Yankee dryer 15.

  As shown in FIGS. 2 and 3, the injection port 23 is formed so as to straddle the upper surface and the inclined side surface of the distal end portion 22. Since the injection port 23 is formed in this manner, the additive solution injected from the injection port 23 is injected in a fan shape as shown by a one-dot chain line in FIG. Yes. Since the spray port 23 is installed so as to face the wet paper W on the Yankee dryer 15, the fan shape formed by the additive solution sprayed from the spray port 23 and the wet paper W are almost perpendicular to each other. It is supposed to cross.

  A pump (not shown) is connected to one end side of the shower pipe 20, and an additive solution is fed into the shower pipe 20 by operating this pump. The additive solution fed into the shower pipe 20 by operating the pump passes through the interior space of the nozzle 21 through the interior of the shower pipe 20, and the wet paper W on the Yankee dryer 15 from the injection port 23. It comes to be injected.

The shower pipe 20 is installed so that the distance L ₁ [mm] between the wet paper web W and the ejection port 23 is 50 to 250 mm, and more preferably 50 to 150 mm. If the distance L ₁ [mm] between the wet paper web W and the ejection port 23 exceeds 250 mm, the shower is likely to be scattered and the fixing rate is lowered. On the other hand, when the separation distance L ₁ [mm] between the wet paper W and the ejection port 23 is less than 50 mm, the formation of the paper is deteriorated due to the ejection pressure. Moreover, since the area sprayed from one spray port becomes small, the wrapping of the additive solution sprayed from the adjacent spray port 23 is less likely to cause uneven coating. As a result, partial drying failure and There is a high possibility of wrinkles. Furthermore, a larger amount of coating is required, resulting in an increased load on the dryer drying capacity, which affects productivity.

If the distance L ₁ [mm] between the wet paper web W and the ejection port 23 is in the above range, the product will be easily collapsed. It becomes. The wet paper W is preferably made of paper with a weight of 20 g / m ² or more. If the basis weight is less than 20 g / m ^2, it is not preferable because the formation of paper or wrinkles occurs when showering.

When jetting onto wet paper W having a rice basis weight of less than 20 g / m ² , paper strength that can withstand shower jetting may be applied to wet paper W. In this case, the wet paper strength length of the wet paper W is preferably 40 cN or more. When the wet paper strength length is less than 40 cN, it is not preferable because the formation of paper or wrinkles occurs when shower coating is performed. However, the wet paper strength at this time was measured based on JIS P 8135 for paper after paper making.

  As shown in FIG. 2, in the nozzle 21, the long sides of the injection ports 23 and the extending direction of the shower pipe 20 are not parallel, and the long sides of all the injection ports 23 are parallel to each other. Is installed. By forming the injection port 23 in this manner, the fan-shaped surfaces formed by the additive solution injected from the injection port 23 are parallel to each other.

An angle θ ₂ [degree] between the long side of the injection port 23 and the extending direction of the shower pipe 20 is 5 to 30 degrees, and more preferably 8 to 25 degrees. If the angle θ ₂ [degree] is more than 30 degrees, the coating area per spray port 23 is narrowed, so that the wrapping of the additive solution sprayed from the adjacent nozzles 21 is reduced. Is likely to cause partial drying defects and wrinkles, and as a result, suitable quality cannot be obtained. Moreover, even if sufficient wrapping is ensured, since the coating amount increases, drying may deteriorate and production may not be suitably performed. On the other hand, if the angle θ ₂ [degree] is less than 5 degrees, it overlaps with the particles applied from the adjacent injection ports 23, and the injection is not uniform, resulting in uneven coating. Wrinkles are likely to occur, and as a result, the required quality cannot be obtained.

The distance L ₂ [mm] (pitch) between the centers of the injection ports 23, which is an interval between the adjacent injection ports 23, is 50 to 120 mm, and more preferably 60 to 100 mm. If the pitch L ₂ [mm] is more than 120 mm, the wrapping of the additive solution sprayed from the adjacent spray ports 23 is reduced, so that coating unevenness occurs and partial drying defects and wrinkles may occur. As a result, a suitable quality cannot be obtained. On the other hand, when the pitch L ₂ [mm] is less than 50 mm, a larger amount of coating is required, so that the load on the dryer drying capacity is increased and the productivity is affected.

  The orifice diameter of the injection port 23 calculated by the above-described equation 1 is 0.5 to 1.1 mm, and more preferably 0.53 to 0.89 mm. If the orifice diameter of the injection port 23 exceeds 1.1 mm, the particles of the additive solution become too large, and coating unevenness tends to occur. In addition, the formation of the paper is easily broken. On the other hand, when the orifice diameter of the injection port 23 is less than 0.5 mm, the additive solution particles become too small, and the additive solution particles are formed in the gap between the injection port 23 and the wet paper web W. As a result, the particles of the additive solution are hardly fixed on the wet paper web W.

In addition, as a nozzle 21 having an orifice diameter of 0.5 to 1.1 mm and having an injection port 23 with 50 ≦ θ ₁ ≦ 110, TPU11001-SS manufactured by Spraying Systems Japan Co., Ltd. TPU110015-SS, TPU1102-SS, TPU11003-SS, TPU9501-SS, TPU95015-SS, TPU9502-SS, TPU9503-SS, TPU8001-SS, TPU80015-SS, TPU650067-SS, TPU65001-SS, TPU65015-SS, etc. are used. be able to.

As shown in FIG.4 and FIG.5, the injection angle (theta) ₁ [degree] in the long side direction of the injection port 23 which is a fan-shaped center angle which the solution of the additive injected from the injection port 23 comprises is 50-110 degree | times. And more preferably 65 to 110 degrees. If the angle θ ₁ [degree] in the long side direction of the ejection port 23 exceeds 110 degrees, the particles are scattered and the fixing rate is lowered. On the other hand, when the spray angle θ ₁ [degree] is less than 50 degrees, the coating area per nozzle is narrowed, so a larger amount of coating is required, resulting in an increased load on the dryer drying capacity. Affects productivity.

Then, the length L ₃ [mm] of the portion where the additive solution sprayed from the mutually adjacent spray ports 23 wraps in the additive solution reaching portion of the wet paper web W is calculated from the following formula (1). Value. However, the distance L ₁ [mm] between the wet paper web W and the ejection port 23, the pitch L ₂ [mm] between the centers of the ejection ports 23, and the center of the sector formed by the additive solution ejected from the ejection port 23. Each value of the injection angle θ ₁ [degree] in the long side direction of the injection port 23 that is an angle satisfies the following formulas (2) and (3). Thus, the length L ₃ [mm] of the portion where the solution of the additive injected from the mutually adjacent injection ports 23 wraps is a value calculated from the following formula (1), A highly viscous additive solution having a viscosity at a temperature of 30 ° C. of 1000 to 2500 mPa · s can be uniformly applied in the width direction of the line.

L ₃ = 2X−L ₂ (1)
Here, X is a value that satisfies Equation (2) and Equation (3) simultaneously.
_{X = L 1 tan (θ 1} /2) ··· (2)
_{X ≧ 3L 2/4 ··· (} 3)

In addition, angle (theta) in FIG. 5 is calculated | required by Formula (4).
θ = 2 arctan (X / L ₁ ) · 180 / π (4)

  Note that a plurality of shower pipes 20 may be installed, and preferably in the range of one to two. In this case, it is preferable that the shower pipe 20 is installed so that the separation distances of all the ejection ports 23 and the wet paper webs W are the same.

  When installing two shower pipes 20, it is preferable that the separation distance of each shower pipe 20 is 30 to 200 mm. Moreover, it is preferable to arrange | position each shower pipe 20 so that the injection nozzle 23 of each shower pipe 20 may not line up along a line direction. More preferably, the injection ports 23 of the shower pipes 20 are arranged so as to appear at equal intervals in the line width direction.

  It is important that the additive solution added to the wet paper W adheres to the wet paper W with a high yield in order to obtain the maximum effect of the additive on the resulting dried web W ′. From this point of view, in the present embodiment, it is preferable to spray the release agent in combination with the additive solution from the viewpoint of improving the yield and manufacturing stability of the additive solution to the wet paper web W.

  Examples of the additive used in the present embodiment include, for example, a water-soluble polymer having a carboxyl group, polyvinyl alcohol, starch or a derivative thereof, methylcellulose, hydroxypropylcellulose, sodium alginate, trant gum, guar gum, xanthan gum, gum arabic, carrageenan , Galactomannan, gelatin, casein, albumin, pull plan, polyethylene oxide, viscose, polyvinyl ethyl ether, sodium polyacrylate, sodium polymethacrylate, polyacrylamide, hydroxylated derivatives of polyacrylic acid, polyvinyl pyrrolidone / vinyl pyrrolidone acetic acid A vinyl copolymer etc. are mentioned. Of these water-soluble polymers, it is preferable to use a water-soluble binder having a carboxyl group from the viewpoint of good water decomposability and the ability to exhibit wet strength by a crosslinking reaction with a crosslinking agent described later. The additive solution has a viscosity of 1000 to 2500 mPa · s at a temperature of 30 ° C.

  The water-soluble polymer having a carboxyl group is an anionic water-soluble binder that easily forms a carboxylate in water. Examples thereof include polysaccharide derivatives, synthetic polymers, and natural products. Examples of the polysaccharide derivative include carboxymethylcellulose (CMC) or a salt thereof, carboxyethylcellulose or a salt thereof, carboxymethylated denven or a salt thereof, and an alkali metal salt of carboxymethylcellulose is particularly preferable. Examples of the synthetic polymer include a salt of an unsaturated carboxylic acid polymer or copolymer, a salt of a copolymer of an unsaturated carboxylic acid and a monomer copolymerizable with the unsaturated carboxylic acid, and the like. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic anhydride, maleic acid, and fumaric acid. Examples of monomers that can be copolymerized with these include esters of these unsaturated carboxylic acids, vinyl acetate, ethylene, acrylamide, and vinyl ether. Particularly preferred synthetic polymers are those using acrylic acid or methacrylic acid as the unsaturated carboxylic acid. Specifically, polyacrylic acid, polymethacrylic acid, acrylic acid-methacrylic acid copolymer salt, acrylic acid or methacrylic acid. Examples thereof include a salt of a copolymer of an acid and an alkyl acrylate or an alkyl methacrylate. Examples of natural products include sodium alginate, xanthan gum, gellan gum, tarragant gum, pectin and the like.

  CMC, which is a water-soluble polymer added to the wet paper W, has a degree of etherification of 0.6 to 2.0, particularly 0.9 to 1.8, and more preferably 1.0 to 1.5. Is preferable from the viewpoint of good performance as a binder.

  CMC is impregnated with an aqueous detergent containing a specific divalent metal ion, such as calcium ion or zinc ion, and a water-soluble organic solvent. It is insolubilized and can exhibit the strength of paper that can withstand cleaning and wiping operations. On the other hand, the water-soluble polymer having no carboxyl group is an aqueous cleaning in which a predetermined amount of an inorganic salt such as sodium sulfate, potassium sulfate or magnesium sulfate or an organic acid salt such as sodium citrate, potassium citrate or sodium tartrate is blended. By impregnating the agent, the water-soluble polymer is salted out and insolubilized, and the strength of the paper that can withstand cleaning and wiping operations can be expressed.

  In order to improve the yield of CMC to pulp fibers, a cationic polymer can be added. However, some cationic polymers improve the wet strength, and at the same time, the water solubility deteriorates, so care must be taken.

  As the water-soluble polymer added to the wet paper W, water-swellable CMC can also be used. This is due to the cross-linking of specific metal ions and borate ions, etc., to exhibit water-soluble polymer function (function to hold fibers) while remaining unswelled, and to develop paper strength that can withstand cleaning and wiping operations. Can do. When using a water-swellable CMC, it is preferable to use a salting-out substance together because the yield can be improved.

  In order to produce a water-degradable cleaning article from the water-degradable sheet thus obtained, a water-soluble polymer insolubilizing substance (crosslinking agent, gelling agent, salting-out substance, organic solvent) is added. For example, at least one agent selected from a crosslinking agent, a gelling agent, a salting-out substance, and an organic solvent that makes the water-soluble polymer insoluble or makes it difficult to swell the water-swellable polymer is added. As a result of insolubilization and non-swelling of the water-soluble polymer, the wet strength of the water-decomposable sheet obtained by this production method can be increased, and it is durable enough to withstand cleaning and wiping even under impregnation with an aqueous detergent. Can do. Moreover, at the time of washing and discarding, the water-soluble polymer insolubilized / unswelled substance is diluted with a large amount of water, and the water-soluble polymer is dissolved in water again, and quickly disintegrates to the fiber level. .

  It is manufactured by impregnating a water-degradable sheet manufactured through the above-described steps with a water-soluble detergent. The impregnation with the cleaning agent can be carried out by, for example, a continuous sheet hitting process, spray transfer of the cleaning agent, or an appropriate method. The impregnation with the cleaning agent may be performed continuously on the continuous water-decomposable sheet or may be impregnated after cutting into a product size.

  An appropriate solvent can be used for the aqueous cleaning agent for impregnating the water-decomposable sheet according to the present embodiment to obtain a wiping sheet. Here, the cleaning agent according to the present invention characteristically contains a polyvalent metal cation. In particular, it is desirable that one or more ions for polyvalent metals selected from the group consisting of alkaline earth metals, manganese, zinc, cobalt and nickel are contained. In particular, a divalent metal cation is desirable, and calcium, strontium, barium, zinc, cobalt, nickel ions are particularly suitable. Of these, calcium ions are desirable.

When such a polyvalent metal cation is contained, a wet strength that can withstand use is developed due to the cross-linking effect caused by the action of CMC fixed on the water-decomposable sheet and the fibers are sufficiently bonded when impregnated with the detergent. This means that sufficient strength is developed during the wiping operation.
And after wiping operation, when touching a large amount of water, such as when flowing into the toilet, the cross-linking effect is diminished and effective water disintegration is expressed.

The ion for polyvalent metal can be contained in the aqueous detergent in the form of a water-soluble metal salt such as hydroxide, chloride, sulfate, nitrate, carbonate, formate, and acetate.
The ion for polyvalent metal is preferably contained so as to be in an amount of 1/2 mol or more, particularly 1/1 mol or more with respect to 1 mol of the carboxyl group in the component contained in the chemical solution. Sufficient cross-linking reaction occurs, and sufficient wet strength is exhibited.

[Other Embodiments]
The coating method of the high-viscosity solution according to the present invention can be applied to the coating of a high-viscosity softening agent, a high-viscosity lotion agent, etc. in addition to the production of the water-degradable sheet described above. As components of the solution applied to the above, surfactants, natural polymers, synthetic polymers, natural polymer salts, synthetic polymer salts, substances cross-linked with natural polymers, and cross-linked synthetic polymers. It is desirable to use at least one kind that is washed from the material group.

  The surfactant is preferably a polyglycerin saturated fatty acid ester having a saturated fatty acid chain length of C12-22. For example, hexaglycerin monostearate, hexaglycerin sesquistearate and the like are preferably used. be able to. From the viewpoint, it is desirable to use a polysaccharide such as agarose, pectin, carrageenan, xanthan gum, gellan gum, locust bean gum or farcelan, or a substance obtained by crosslinking these as a natural polymer. Furthermore, as other natural polymers or synthetic polymers, gelatin, chitosan, hyaluronic acid, alginic acid, polyvinyl alcohol, polyacrylic acid, polyacrylamide, carboxyvinyl polymer, polymethacrylic acid, carboxymethylhydroxyl cellulose, etc. are preferably used. can do.

Below, the application method of the high-viscosity solution according to the present invention is applied to the production of the above-described water-decomposable sheet, and the working effects of the present invention will be clarified while showing examples thereof.
The example manufactured with the manufacturing method of the water-decomposable sheet according to the embodiment shown in Table 1 and the comparative example manufactured with the manufacturing method of other water-decomposable sheets shown in Table 2 are shown in FIG. Manufactured with a felt paper machine, various conditions were changed, and paper strength, water disintegration, CMC fixing amount, and CMC fixing rate were measured. The measuring method is as follows.

In Tables 1 and 2, wet paper strength / longitudinal (cN / 25 mm) and wet paper strength / horizontal (cN / 25 mm) were measured based on JIS P 8135, respectively. The water used here was an aqueous 8% by weight calcium chloride solution, and the applied aqueous solution was 170% of the base paper weight.
About the water disintegration (second) in Table 1 and 2, it measured according to the test of the ease of loosening of JISP4501.
The fixing ratios in Tables 1 and 2 are the estimated amount of CMC adhering to the web with respect to the amount of CMC applied by shower application. The estimated amount of CMC adhesion was estimated in advance by preparing a calibration curve for the increase in wet paper strength (%) due to CMC adhesion, and the ratio (%) of wet paper strength after coating to the wet paper strength of base paper before coating. Is.
Regarding the row of “value of X” in Tables 1 and 2, “X” is given to those in which the value of X simultaneously satisfies the formulas (2) and (3), and “x” is given to those that do not.

  Regarding the row of “continuous operability” in Tables 1 and 2, if there is no particular problem when making paper with an actual machine, ○, if it cannot be uniformly applied in the spray width direction and cannot be used as a product, or some trouble such as paper breakage When the sample occurred and no sample was collected, it was marked as x.

In both the examples and comparative examples, as the raw material pulp constituting the paper stock, a mixture ratio of 9: 1 softwood kraft pulp and hardwood kraft pulp was used, and the freeness of the paper stock was 5 to 15 cc. Further, the paper making was performed at a speed of 250 m / min, and the crepe rate was adjusted to 15%.
In both Examples and Comparative Examples, those having a basis weight of 30 g / m ² measured based on JIS P 8124 were used.
In both Examples and Comparative Examples, an aqueous solution of CMC Daicel 1330 manufactured by Daicel Chemical Industries, Ltd. was used as an additive.

  As the nozzle 21, TPU11001-SS (manufactured by Spraying Systems Japan Co., Ltd.) is used in Example 1 and Comparative Example 13, and TPU11002-SS (manufactured by Spraying Systems Japan Co., Ltd.) is used in Example 2 and Comparative Example 10. ) In Examples 3 and 4 and Comparative Examples 3, 4, 6, and 7, TPU11003-SS (manufactured by Spraying Systems Japan Co., Ltd.) is used in Examples 5 and 6, and Comparative Examples 11 and 13 are TPU650067-SS. (Manufactured by Spraying Systems Japan), TQ150015-SS (manufactured by Spraying Systems Japan) in Comparative Example 9, and TPU1100050-SS (manufactured by Spraying Systems Japan) in Comparative Example 1. In Comparative Example 2, TPU11004-SS (spraying Systems Japan Co., Ltd.), TPU6501-SS (manufactured by Spraying Systems Japan Co., Ltd.) was used in Comparative Example 5, and TPU400067-SS (manufactured by Spraying Systems Japan Co., Ltd.) was used in Comparative Example 8. .

  Example 1 was taken as an example when two shower pipes 20 were installed. Two shower pipes were installed in parallel to the pump. The amount added per pipe is 17.5 kg / t, and the pitch of the injection holes is 115 mm. In these examples, the separation distance between the spray port 23 of each shower pipe 20 and the wet paper W is the same. The distance between the shower pipes 20 was 100 mm, and the shower pipes 20 were installed so that the injection ports 23 of the shower pipes 20 appeared at equal intervals in the line width direction.

  As is apparent from Tables 1 and 2, the water-decomposable sheets according to Examples 1 to 6 coated with CMC by the high viscosity solution coating method according to the present invention have a higher CMC fixing rate than the comparative example. I found out.

  The high viscosity solution coating method according to the present invention can be suitably used for coating high viscosity softeners, high viscosity lotions, and the like.

DESCRIPTION OF SYMBOLS 10 ... Top felt 11 ... Bottom felt 12 ... Top roll 13 ... Bottom roll 15 ... Yankee dryer 16 ... Touch roll 19 ... Hood 20 ... Nozzle and shower pipe W ... Wet paper W '... Web after drying

Claims (2)

The wet paper or paper is separated from the wet paper by a distance L ₁ [mm] and is arranged in parallel in the line width direction at an interval L ₂ [mm], and is conveyed from an injection port having an orifice diameter of 0.5 to 1.1 mm. A high-viscosity solution having a viscosity of 1000 to 2500 mPa · s at 30 ° C. is jetted in a fan shape with an injection pressure of 3.0 to 20.0 kPa and an angle θ ₁ [degrees] on a wet paper or paper. A method of applying a viscous solution,
The high-viscosity solution is jetted so that the fan-shaped surfaces of the high-viscosity solution jetted from the jet nozzles are parallel to each other and intersect at an angle θ ₂ [degree] with respect to the line width direction,
The length L ₃ [mm] of the portion where the high-viscosity solution sprayed from the mutually adjacent spray ports wraps at the high-viscosity solution reaching portion of the wet paper is 50 ≦ L ₁ ≦ 250, 50 ≦ L ₂ ≦ 120. Satisfying the formula (1) under the condition of 50 ≦ θ ₁ ≦ 110,
A method for applying a high-viscosity solution.
L ₃ = 2X−L ₂ (1)
Here, X is a value that satisfies Equation (2) and Equation (3) simultaneously.
_{X = L 1 tan (θ 1} /2) cos (θ 2) ··· (2)
_{X ≧ 3L 2/4 ··· (} 3) The coating method of the high-viscosity solution according to claim 1, wherein the angle θ ₂ [degree] is 5 to 30 degrees.

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