JP2003081262A - Roller carton with paper blade and paper blade - Google Patents

Abstract

(57) [Problem] To make it possible to efficiently form a paper blade having a saw-toothed blade that is free from peeling, hard to set, and hard to break, while suppressing wear of a used device. SOLUTION: A paper base material is impregnated and hardened with a reinforcing resin containing spherical inorganic particles to strengthen the paper base material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting blade used for cutting sheets such as wrap film, aluminum foil, and cooking paper, and a paper blade having a serrated blade based on paper, and The present invention relates to a roll carton containing a roll of the above-mentioned sheets, which roll has a paper blade.

[0002]

2. Description of the Related Art Conventionally, a paper base material having a saw-toothed blade is strengthened by impregnating and hardening a resin for hardening treatment, and further abrasive grains are contained only on the upper end surface of the blade or on the upper end surface and side surfaces. It is known to apply and harden the fixing resin to be used as a paper blade for cutting the sheets drawn out from the roll carton to a required length (JP-A-7-315373).

[0003]

By the way, the paper blade using the above paper as a base material, like a general metal cutting blade, separates the paper roll carton from the cutting blade when the roll carton is discarded. It has the advantage of not having to be discarded.

However, the above-mentioned conventional paper blade has the following problems.

(1) In the above-mentioned conventional paper blade, abrasive grains are fixed to the surface impregnated and cured with a curing resin with a fixing resin, and good sharpness can be obtained by utilizing sharp edges of the abrasive grains. When the blade edge comes into contact with another object as well as when cutting the sheets, the fixed abrasive grains are easily caught, and the abrasive grains are likely to be peeled off.

(2) It is preferable that the hardening treatment resin that is impregnated and hardened to reinforce the serrated blade is hard for reinforcing the blade, but if it is too hard,
It is difficult to use a curing resin having an appropriate hardness, because the blade tip is likely to crack and, on the contrary, if the blade is too soft, the blade is easily set.

(3) The productivity is poor because the coating and curing must be carried out for two kinds of resin for curing treatment and fixing resin.

(4) Since the abrasive grains are amorphous particles having sharp edges, the equipment used for applying the fixing resin containing the abrasive grains, auxiliary equipment, cutting dies, etc. are easily damaged. For example, if the abrasive grains enter a bearing portion such as a guide roller, the bearing portion may be worn in a short time operation.

The present invention has been made in view of the above-mentioned problems of conventional paper teeth, and is a paper blade having a saw-toothed blade that does not cause peeling, is hard to set, and is hard to break.
An object of the present invention is to enable efficient formation while suppressing wear of the used device.

[0010]

For the above-mentioned purpose, the present invention is characterized in that a reinforcing resin containing spherical inorganic particles is impregnated and cured into a paper base material having a saw-toothed blade. It provides a paper blade that does.

According to the above-mentioned invention, even if the reinforced resin is not so hard as to cause cracking of the blade edge, the contained spherical inorganic particles act as an aggregate, so that the blade can be sufficiently reinforced. It is possible to prevent the blade from sagging. Further, due to this reinforcing action, the sharp tip state of the saw-toothed blade is maintained for a long period of time, so that good sharpness can be obtained simply by impregnating and hardening the reinforcing resin containing the spherical inorganic particles, thereby improving productivity. Excel. Furthermore, the inorganic particles used in the present invention are not irregular particles having sharp edges such as abrasive grains, but are spherical particles having roundness as a whole,
Although the sharpness cannot be expected, it does not get caught and peeled off, or the used device is worn in a short time.

In the present invention, the spherical inorganic particles have an average particle diameter of 1 to 50 μm and are contained in an amount of 3 to 30 parts by weight in the reinforcing resin containing the spherical inorganic particles, and the paper base material is bamboo pulp. 50% by weight or more, and the reinforcing resin is a cured product of a moisture-curable silicone-acrylic resin containing at least a tertiary amino group-containing acrylic resin and an epoxy group-containing silicon compound. It is included as.

The present invention also provides a roll carton with a paper blade, characterized by having any of the above paper blades.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The paper blade of the present invention is one in which a reinforcing resin containing spherical inorganic particles is impregnated and cured on a paper base material having a sawtooth-shaped blade.

The spherical inorganic particles in the present invention refer to inorganic particles in the form of particles having a roundness as a whole with almost no sharp edges. As the inorganic particles, for example, alumina,
Although silicon carbide, silicon nitride, aluminum, cerium oxide, titanium oxide, titanium nitride, titanium carbide, zirconium oxide and the like can be mentioned, alumina is preferable from the viewpoint of availability and cost.

The spherical inorganic particles have an average particle size of 1 to 50.
It is preferably μm. If the average particle size is too small,
If it is difficult to obtain good dispersibility in the reinforcing resin and the average particle size is too large, it becomes difficult to obtain a good reinforcing effect due to the action of the aggregate and peeling easily occurs. Further, the spherical inorganic particles are preferably contained in the reinforcing resin containing the spherical inorganic particles in an amount of 3 to 30 parts by weight. If the content of the spherical inorganic particles is too small or too large, it becomes difficult to obtain a sufficient reinforcing effect.

As the reinforcing resin in the present invention, an ultraviolet curable resin, a thermosetting resin, a two-component reaction curable resin or the like can be used, but it has excellent water resistance and has an appropriate flexibility such that it does not easily crack. Moisture-curing silicone-acrylic resin obtained by mixing at least a tertiary amino group-containing acrylic resin-based main agent and an epoxy group-containing silicon compound-based curing agent, because the spherical inorganic particles exert an excellent reinforcing effect by the aggregate effect. Is preferred.

The moisture-curable silicone / acrylic resin will be further described below.

The tertiary amino group-containing acrylic resin used as the main agent is a polymer of a tertiary amino group-containing acrylic monomer, and the tertiary amino group-containing acrylic monomer is, for example, 2- Dimethylaminoethyl (meth)
Acrylate, 2-diethylaminoethyl (meth) acrylate, 3-dimethylaminopropyl (meth) acrylate, 3-diethylaminopropyl (meth) acrylate and the like can be mentioned.

As the epoxy group-containing silicon compound used as a curing agent, a compound having both an epoxy group and a hydrolyzable silyl group is suitable, and a vinyl polymer having both reactive groups of these types and , A silane coupling agent having an epoxy group, or a silicone resin having both reactive groups of both types.

In order to prepare the vinyl polymer having both the epoxy group and the hydrolyzable silyl group, various known and conventional methods can be applied.

Examples of the epoxy group-containing silane coupling agent include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, and γ-glycine. Sidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyl Various epoxysilane compounds such as diethoxysilane; γ-isocyanatopropyltriisopropenyloxysilane or γ-
Two or more epoxies in one molecule obtained by partially hydrolyzing and condensing various isocyanate silane compounds such as isocyanate propyltritrimethoxysilane and glycidol; or various epoxy silane compounds described above. Examples thereof include a compound having both a group and a hydrolyzable silyl group.

Examples of the silicone resin having both the epoxy group and the hydrolyzable silyl group include compounds such as cyclic tetrasiloxanes represented by the following structural formulas.

[0024]

[Chemical 1] (However, Gly in the formula represents a 3-glycidoxypropyl group.)

In preparing the moisture-curable silicone-acrylic resin preferably used in the present invention, (the number of moles of the tertiary amino group in the tertiary amino group-containing acrylic resin)
It is preferable to mix such that / (the number of moles of epoxy groups in the epoxy group-containing silicon compound) is in the range of about 0.3 to about 3.0, and more preferably 0.5 to 2.0.
The ratio is preferably within the range of 0.8, and more preferably within the range of 0.8 to 1.2.

The above-mentioned moisture-curing type silicone-acrylic resin is one which is cured at room temperature by the following reaction mechanism.

[0027]

[Chemical 2]

As described above, the moisture-curable silicone-acrylic resin that can be preferably used in the present invention is one in which the reaction proceeds and cures due to the moisture in the air.
It is particularly excellent in water resistance as compared with the conventionally used ultraviolet curable resin or ionizing radiation curable resin.

Further, a compound having a hydrolyzable silyl group and / or a silanol group other than the epoxy group-containing silicon compound may be added to the moisture-curable silicone / acrylic resin. This makes it possible to obtain a paper blade that is more excellent in terms of various properties such as water resistance and hardness.

If necessary, various types of curing catalysts, fillers, thickeners,
A water repellent, a dispersant, or the like can be appropriately added and used.

The moisture-curable silicone-acrylic resin obtained as described above is used in a so-called two-component type in which a curing agent composed of an epoxy group-containing silicon compound is mixed with other components immediately before use. .

The paper edge of the present invention is a solution of a reinforcing resin in which the spherical inorganic particles are dispersed (hereinafter referred to as "reinforcing treatment liquid").
Is adhered to and impregnated into the paper base material in a raw paper state before being cut, and then the strengthening resin in the strengthening treatment liquid is cured under heating or at room temperature, and then the paper base material is cut into a necessary width and sawtooth. By forming the blades in the shape of a circle, it can be obtained with high productivity. Further, although the productivity is slightly inferior, it can be obtained by cutting the paper substrate to a required width in advance and subjecting the paper base material having the sawtooth-shaped blade to the impregnation hardening treatment of the strengthening treatment liquid.

The reinforcing resin solution is preferably adjusted with a solvent so that the solid content is 20 to 50% by weight. If the solid content is too low, it is difficult to obtain a sufficient amount of the reinforcing resin to be impregnated and impregnated into the paper base material. Conversely, if the solid content is too high, it will be difficult to penetrate into the interior of the paper base material and the amount of adhesion to the surface will be reduced. Is likely to be excessive. The solvent may be selected according to the reinforcing resin used, but a mixed solution of methyl ethyl ketone and ethyl acetate can be used as the solvent of the moisture-curable silicone-acrylic resin. The mixing ratio of both is 30 to 50% by weight of methyl ethyl ketone and 70 to 50 of ethyl acetate.
It is preferable to mix them so as to add up to 100% by weight.

Brushing, roller coating, dip coating, gravure coater coating, roll coater coating and the like can be used as a means for adhering and impregnating the reinforcing treatment liquid to the paper substrate, but it can be uniformly applied to the paper substrate. The dip coating method of immersing the paper base material in the strengthening treatment liquid is preferable because it is easy to impregnate the strengthening treatment liquid. Further, it is preferable to impregnate the inside of the paper base material with the strengthening treatment liquid as much as possible, and in particular, the paper base material taken out from the strengthening treatment liquid is sandwiched between the squeezing rollers to squeeze out the remaining excess strengthening treatment liquid. ,
It is preferable to push the strengthening treatment liquid into the paper substrate.

The application of the strengthening treatment solution to the paper substrate is preferably carried out such that the 8~40g / m ² approximately in terms of solid content contained, and particularly preferably 10 to 30 g / m ² . If this coating amount is too small, it is difficult to obtain the necessary reinforcing effect, and the sharpness and durability are likely to deteriorate, and conversely, if it is too large, the sharpness tends to be poor, and the curing period becomes longer and the productivity decreases. , Surface cracks and cracks tend to occur after curing.

As the paper base material, any paper material that can be impregnated with the above-mentioned strengthening treatment liquid can be used, and for example, bamboo pulp paper, kenaf paper, medium density paper, etc. can be suitably used. . In particular, a paper base material containing 50% by weight or more of bamboo pulp is preferable because it is elastic and has a short fiber, so that there is little risk of fluffing at the tip when processed into a paper blade, and excellent sharpness and strength can be obtained.

The weight of the paper base material is 200 to 400 g / m ^2.
Is preferred. If the weight of the paper substrate is too small,
Even if it is reinforced with the reinforcing resin containing the spherical inorganic particles, it becomes difficult to obtain the necessary blade strength and it becomes difficult to maintain the sharpness. Further, even if the weighing is too large, an appropriate resin impregnation amount cannot be obtained and the sharpness becomes poor, or a large amount of the strengthening treatment liquid is impregnated, the curing period becomes long and the productivity decreases, or the surface of the surface after curing is reduced. Cracks and cracks are more likely to occur.

The paper blade of the present invention obtained as described above can be suitably used as a cutting blade attached to a roll carton for storing rolls such as wrap film, aluminum foil and cooking paper.

As shown in FIG. 1, the roll carton with a paper blade of the present invention has a paper blade 2 of the present invention adhered to a predetermined position of a paper-made roll carton 1, and has a conventional appearance. It is exactly the same as the roll carton with the cutting blade of. Incidentally, FIG.
In the example shown in, the paper blade 2 is adhered to the inside of the lower end portion of the lid front piece 3 of the roll carton 1, but the adhering position of the paper blade 2 is the upper or lower end portion of the front wall 4 of the main body or the like. It may be at any position similar to the conventional one.

The method of adhering the paper blade 2 to the paper roll carton 1 is not particularly limited, and may be ultrasonic sealing, high frequency sealing, thermocompression bonding with a polyethylene adhesive or heat sealing agent, or ethylene. A hot melt adhesive such as a vinyl acetate copolymer, an adhesive or a cold sealant can be used.

As an example of a specific method for adhering the cutting blade, a method for adhering the paper blade 2 when a water-based cold sealant is used will be described below.

As the aqueous cold sealant, a copolymer of methyl methacrylate and acrylic acid (component A) and a copolymer of acrylic acid ester and methacrylic acid (component B)
And rubber-modified polymethacrylic acid ester (C component),
The thing containing the silica powder is mentioned.

The component A forms the base of the adhesive resin, and the modified acrylic water-based cold sealant based on this is used to eliminate the deterioration over time of conventional natural rubber-based water cold sealants. be able to.

The component B is for improving the printing characteristics of the water-based cold sealant and enabling coating with a gravure coater, and is 12 to 6 per 100 parts by weight of the component A.
It is preferably contained in an amount of 0 part by weight.

Component C is modified by mixing a modified rubber with polymethacrylic acid ester, and the heat resistance can be improved by adding this. C component is 80 to 23 relative to 100 parts by weight of A component.
It is preferred that 0 parts by weight is blended.

The aqueous cold sealant preferably used in the present invention preferably contains 7 to 35 parts by weight of silica powder with respect to 100 parts by weight of the total amount of the above-mentioned components A to C. By adding the silica powder within this range, it is possible to prevent blocking after the coating and drying of the present aqueous cold sealant.

It is preferable that the components A and C are emulsions, and the component B is an aqueous solution. A
The present water-based cold sealant containing component (C) and silica powder is supplied to a gravure coater by diluting it with water as needed. The dilution is preferably performed so that the water content by weight is 4 to 6 times that of the silica powder contained.

The roll carton with a paper blade of the present invention as shown in FIG. 1 can be easily manufactured as follows when the above-mentioned aqueous cold sealant is used.

First, the roll carton 1 and the paper blade 2 are each provided with a coating and drying surface of the aqueous cold sealant.

The formation of the coated and dried surface on the roll carton 1 is performed at a predetermined position (the position where the paper blade 2 should be attached) or the roll carton 1 on the base paper to be the roll carton 1.
The water-based cold sealant is applied to a predetermined position (same as above) on the blank and dried. These coating operations can be performed with a roll coater as in the conventional case, but can be performed with a gravure coater by using the aqueous cold sealant. When the coating work is performed with the gravure coater, the position and shape of the coating can be set easily and accurately, and the workability can be improved.

On the other hand, the work efficiency is good when the coated and dried surface is formed on the paper blade 2 with respect to the long raw material before the saw teeth are formed.

Drying after application of the aqueous cold sealant is
For example, it can be performed by blowing warm air.

After the dry coating surface of the water-based cold sealant is formed on the predetermined position of the roll carton 1 and the paper blade 2 as described above, when the roll carton 1 is in a blank state, The paper blade 2 can be adhesively fixed to the roll carton 1 by pressing and pressing the coated and dried surfaces together. The subsequent assembly of the roll carton 1 and the like are exactly the same as the conventional one.

[0054]

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

Example 1 "BZ1161" manufactured by Dainippon Ink and Chemicals, Inc. as a main agent composed of a tertiary amino group-containing acrylic resin, and manufactured by Dainippon Ink Chemicals, Inc. as a curing agent composed of an epoxy group-containing silicon compound. Moisture-curable silicone-acrylic resin using "BZ1163" of No. 3 was used as a reinforcing resin.

2 parts of the above-mentioned curing agent are added to 100 g of the above-mentioned base material.
Add 5g and mix methyl ethyl ketone and ethyl acetate 4: 6.
The solvent is mixed in the weight ratio of, and the average particle diameter is 12μ with respect to the reinforced resin solution diluted so that the solid content becomes 25% by weight.
The spherical alumina particles of m were dispersed so as to be 5% by weight in the total solid content to obtain a strengthening treatment liquid.

To the above-mentioned strengthening treatment liquid, "KT Kent" (weighing 250
g / m ² ) is dipped as a paper substrate, surplus strengthening treatment liquid adhering to the surface is scraped off with a doctor blade, and then left at room temperature for 1 week to cure the moisture-curable silicone / acrylic resin. To No. Ten test pieces of 1 to 10 were cut out, and the compressive strength of each of them was measured by the ring crush method of JIS P8126.

The results are shown in Table 1.

Comparative Example 1 From the paper base material used in Example 1, No. Ten test pieces 1 to 10 were cut out, and the compressive strength of each was measured by the ring crush method of JIS P8126.

The results are shown in Table 1.

Comparative Example 2 The paper base material of Example 1 was immersed in a resin solution having the same composition as that of the reinforcing resin solution used in Example 1 except that spherical alumina particles were not included, and the paper substrate was attached to the surface. After scraping off the excess strengthening treatment liquid with a doctor blade, it was left at room temperature for 1 week to cure the moisture-curable silicone-acrylic resin. Cut out 1 to 10 test pieces,
The compressive strength of each of them was measured by the ring crush method of JIS P8126.

The results are shown in Table 1.

Example 2 The same measurement as in Example 1 was carried out in the same manner as in Example 1 except that the basis weight of the paper was 300 g / m ² .

The results are shown in Table 2.

Comparative Example 3 From the paper base material used in Example 2, No. Ten test pieces of 1 to 10 were cut out, and the compressive strength by the ring crush method of JIS P 8126 was measured for each of them.

The results are shown in Table 2.

Comparative Example 4 The paper base material of Example 2 was immersed in a resin solution having the same composition as that of the reinforcing resin solution used in Example 1 except that spherical alumina particles were not contained, and the paper substrate was adhered to the surface. After scraping off the excess strengthening treatment liquid with a doctor blade, it was left at room temperature for 1 week to cure the moisture-curable silicone-acrylic resin. Cut out 1 to 10 test pieces,
The compressive strength of each of them was measured by the ring crush method of JIS P8126.

The results are shown in Table 2.

[0069]

[Table 1]

[0070]

[Table 2]

When the wrap film was accommodated, fed out to an appropriate length and cut 100 times, no peeling of the inorganic particles occurred in both Example 1 and Example 2.

[0072]

The present invention is as described above and has the following effects. (1) The paper blade of the present invention can sufficiently reinforce the blade because the contained spherical inorganic particles act as an aggregate even if the reinforced resin is not so hard as to cause cracks in the blade edge. It is possible to prevent the blade from sagging.

(2) Since the sharpened tip of the saw-toothed blade is maintained for a long period of time by this reinforcing action, good sharpness can be obtained only by impregnating and hardening the reinforcing resin containing spherical inorganic particles. And is excellent in productivity.

(3) Since the inorganic particles used in the present invention are not spherical particles having sharp edges such as abrasive grains but spherical particles having a roundness as a whole, improvement in sharpness cannot be expected. It does not get caught and peeled off, nor does it wear the used device in a short time.

(4) The roll carton with a paper blade provided with the paper blade of the present invention has excellent sharpness when cutting the sheets drawn out from the roll carton, and this sharpness can be maintained for a long period of time.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a roll carton with a paper blade according to the present invention.

[Explanation of symbols]

1 roll carton 2 paper blades 3 Front piece 4 body front wall

Claims (5)

[Claims] 1. A paper blade, characterized in that a reinforcing resin containing spherical inorganic particles is impregnated and cured into a paper base material having a sawtooth-shaped blade. 2. The spherical inorganic particles have an average particle size of 1 to 50.
The paper blade according to claim 1, characterized in that the content is 3 to 30 parts by weight in a reinforcing resin containing spherical inorganic particles. 3. The paper blade according to claim 1, wherein the paper substrate contains bamboo pulp in an amount of 50% by weight or more. 4. The reinforced resin is a cured product of a moisture-curable silicone-acrylic resin containing at least a tertiary amino group-containing acrylic resin and an epoxy group-containing silicon compound. The paper blade according to any one of 1. 5. A roll carton with a paper blade, comprising the paper blade according to claim 1.