JPH08157302A - Production of sheet for keeping freshness of cut flower - Google Patents

Abstract

PURPOSE: To provide a process for producing a sheet for keeping the freshness of a cut flower by using aluminum sulfate as a life-prolonging agent for cut flower. CONSTITUTION: A sheet for keeping the freshness of a cut flower can be produced by applying a layer of a life-prolonging agent for cut flower composed mainly of aluminum sulfate to a surface substrate. The life-prolonging layer is especially preferably produced by using an aqueous solution of aluminum sulfate having a pH adjusted to 2.5-3.5 by the addition of a salt of a weak acid and a strong alkali.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cut flowers in the case of using aluminum sulfate as a life-prolonging agent for cut flowers in order to put the cut flowers into water for use in a vase or the like, clarify the water and maintain the freshness of the cut flowers. The present invention relates to a method for producing a freshness maintaining sheet.

[0002]

2. Description of the Related Art Conventionally, various methods have been tried to extend the life of cut flowers. For example, cutting the stems of cut flowers in water to improve landing, exchanging fresh water at appropriate times to avoid contact with rotten water, or burning the cut ends of cut flower stems. Has been taken. However, in general, methods such as cutting in water or baking a cut to improve landing are extremely ineffective. In addition, frequent water replacement is cumbersome, and the life-prolonging effect cannot be expected to a great extent.

On the other hand, many kinds of agents called cut flower life-prolonging agents are commercially available in florists and garden shops. The life-prolonging effect and action of these life-prolonging agents on cut flowers are different, and when roughly divided into the action functions of the life-prolonging agents, life-prolonging agents mainly for sterilization and growth inhibition of bacteria, purification, and clarification are the main. Life prolonging agents, nutrients and the like can be mentioned. As a life prolonging agent, chlorine-based chemicals are often used. Although chlorine-based chemicals have excellent bactericidal activity, most of them are volatile and are consumed in the process of use or diffuse into the air. Therefore, the activity is likely to be lost over time, and the life-prolonging effect of the cut flowers is weakened. Therefore, a large amount of life-prolonging agent is required to maintain the effect. In addition, chlorine-based chemicals are likely to cause harmful chlorine gas and are likely to be accompanied by problems such as harming the surrounding atmosphere. Therefore, in order to suppress the chlorine odor, there is no choice but to limit the amount used. As a result, it is used by eluting it little by little, but in that case, there is a drawback that a satisfactory life prolonging effect cannot be obtained. Incidentally, examples of such a bactericide include sodium dichloroisocyanurate, hypochlorite, chlorite and the like.

As the life prolonging agent, a water-soluble inorganic aluminum compound is generally used. This kind of compound
It has the function of aggregating impurities and dust in the water, keeping the water in which cut flowers are always active in a clear state, eliminating the blockage of cut flower conduits due to impurities, and actively promoting clean landing on the stems of cut flowers. Since it has odor and is generally non-volatile, it does not lose its efficacy over time unlike the above-mentioned life prolonging agent. However, the life prolonging agent is generally liquid, has a low pH, and has problems such as being difficult to handle. Examples of this type of life prolonging agent include polyaluminum chloride, aluminum sulfate, potassium alum and the like.

The nutrient of (1) positively supplies nutrients to cut flowers to prolong the life, but has almost no effect of removing various bacteria and impurities existing in water, and rather, the growth of bacteria. Leads to. Since the nutritional supplement alone has little effect on the survival of cut flowers, it is necessary to use the above fungicides in combination. By the way, as a nutrient for cut flowers, glucose, sucrose, urea, potassium salt and the like are exemplified.

In recent years, since it is convenient to carry and easy to use,
Providing a life-prolonging agent layer containing a chlorine-based bactericide on one side of the base material,
A sheet for maintaining the freshness of cut flowers is also developed, in which an adhesive layer and a release sheet are laminated on the other side. In this cut flower freshness-retaining sheet, the pressure-sensitive adhesive layer of the laminate, from which the release sheet has been peeled off, is wrapped around the stem and used as it is in a vase.

The surface layer (life-prolonging agent layer) of the freshness-maintaining sheet contains a chlorine-based bactericide, and when handling it, the chlorine-based bactericide is often touched with bare hands, which is unsanitary. When this sheet is put into a vase together with cut flowers, most of the chlorine-based disinfectants are dissolved in water within a short time because the chlorine-based bactericide is exposed on the surface. When a large amount of the chlorine-based bactericide is dissolved in water in this way, there is a risk that a chlorine odor will drift around and give an unpleasant odor, or may adversely affect cut flowers. In addition, since the chlorine-based bactericide gradually loses its activity and the effect cannot be maintained for a long time, if most of the bactericide is released in a short time after the introduction, it becomes difficult to maintain the life-prolonging effect for a long time. . In order to make up for such drawbacks of the freshness-retaining sheet, most of the periphery of the life-prolonging agent layer containing a chlorine-based bactericide is covered with a water-impermeable layer so that the chemical is gradually added through a specific portion. It has been proposed to dissolve it in water, but this is also insufficient in terms of the life-prolonging effect of cut flowers.

Therefore, an aluminum compound such as aluminum sulfate (cut flower prolonging agent), which has an extremely high effect of prolonging the life of cut flowers, is provided on the surface base material, and a protective layer is further provided on the cut flower prolonging agent layer to ensure safety and hygiene. Moreover, it is easy to use,
The inventors of the present invention have previously proposed a freshness-preserving sheet having an excellent effect of extending the life of cut flowers.

[0009]

[Problems to be Solved by the Invention] However, sulfuric acid
Cut containing a flower-sustaining agent layer with a low pH, such as luminium
The flower freshness preservation sheet has various difficulties in its production.
I'm holding. Especially, aluminum sulfate, which has an excellent life-prolonging effect on cut flowers.
A preferable coating amount (use
The size of the freshness preservation sheet is 3 cm x 5 cm,
(If the amount of water for activating cut flowers is 500 cc)
For Al₂(SO_Four)₃10-60 g / m in conversion²And
It Below, the coating amount and concentration of aluminum sulfate are all
Al₂(SO_Four) ₃Converted display (aluminum sulfate
Usually has a significant amount of water of crystallization, and that amount is
It is easy to change due to various conditions).

From the above, the coating amount is a considerable amount, and a high concentration of aluminum sulfate (concentration = 27% by weight, p
It is difficult to obtain a desired coating amount unless H = 2 and viscosity = 20 cps) are used. By the way, when the concentration of aluminum sulfate is low, the viscosity is greatly reduced and the coating amount is small, so that the coating work must be repeated many times in order to obtain the required coating amount. As a result, the workload is high and inefficient. Therefore, it is possible to apply a binder or a thickener mixed with an aqueous solution of aluminum sulfate, but when the binder or the thickener is dissolved or dispersed in water, the dispersion or the like may block the conduit of cut flowers. And
It has a negative effect on the life prolonging effect. Further, aluminum sulfate has a strong acidity, and it is also a great cause that it is extremely difficult to use a binder together and to increase the viscosity. Also,
The high-concentration aluminum sulfate aqueous solution has a low pH of 1.5 to 2, which causes a problem that the guide rolls of the coating device and the drying oven are rusted during coating, and the high-concentration aqueous solution of aluminum sulfate on work clothes and bare hands of workers. If touched, work clothes may be damaged or the hands may be rough. On the other hand, since aluminum sulfate contains water of crystallization, when the aluminum sulfate layer of the sheet obtained by coating is exposed to the air, the aluminum sulfate layer absorbs water, resulting in curling of the product, making it unusable. Can also happen. In order to solve this, a specific porosity is required for the aluminum sulfate layer after coating, and various measures (for example, twice coating or constantly changing coating temperature during coating) are required to satisfy the porosity. Is. From the above, there is a strong demand for the production (method) of a freshness-maintaining sheet for cut flowers, which can safely and simply process a life-prolonging agent layer containing aluminum sulfate as a main component and has a sufficient life-prolonging effect.

[0011]

The present invention provides a method for producing a sheet for maintaining freshness of cut flowers, which comprises a surface flower and a cut flower life-prolonging agent layer containing aluminum sulfate as a main component.
To provide a cut flower prolongation agent layer using an aqueous solution whose pH is adjusted by adding a weakly acidic strong alkaline salt so that the pH of the aqueous solution containing aluminum sulfate used for forming the cut flower prolongation agent layer is 2.5 to 3.5. A method for producing a sheet for maintaining the freshness of cut flowers, which comprises:

[0012]

From the above, the present inventors diligently studied the conditions under which the strongly acidic aluminum sulfate can be safely processed, and the life-prolonging effect on cut flowers can be sufficiently maintained. As a result, a weakly acidic strong alkali salt, especially sodium carbonate, was added to the aqueous solution of aluminum sulfate to adjust the pH of the solution to 2.5 to 3.5 (equivalent to a 3 to 30-fold dilution of a 27 wt% aqueous solution of aluminum sulfate). It was found that, when adjusted to 3.0 to 3.5, more preferably, the solution can be easily applied to the surface of the substrate without lowering the viscosity of the solution. It was also found that its preparation was easy. When the aluminum sulfate aqueous solution thus prepared is used for coating, curling of the product after coating due to the influence of aluminum sulfate crystallization water can be avoided.
Moreover, it has been found that a freshness-keeping sheet for cut flowers can be obtained at almost the same level as the life-prolonging effect when finished with a solution of aluminum sulfate alone (pH about 2).

Thus, the present invention relates to a method for producing a sheet for maintaining the freshness of cut flowers, which comprises a surface base material and a cut flower life-preserving agent layer containing aluminum sulfate as a main component. Manufacture of a sheet for keeping freshness of cut flowers, which is characterized in that an aqueous solution containing aluminum as a main component is adjusted to pH 2.5 to 3.5 with a weakly acidic strong alkaline salt and then applied and formed on the back surface of a front surface base material. Is the way.

The freshness-keeping sheet for cut flowers (hereinafter, simply referred to as a freshness-keeping sheet) obtained by the method of the present invention is used when a flower shop or the like wraps a flower in a wrapping paper and gives it to a customer. By attaching the sheet to the wrapping paper, when the customer brings back the cut flowers at the same time as adding fashionability and advertising effects, the effect that the cut flowers last longer only by peeling the sheet from the wrapping paper and putting it in a vase in which the cut flowers are arranged Further, it can be used as a sheet with cut flower prolonging agent by adhering or perforating the sheet as an attachment such as a catalog or an appendix to be inserted into postcards or various weekly magazines.

[0015] As a surface substrate which is a component of a cut flower freshness retaining sheets, water permeability is 1000g / m ² · Hr or less, preferably using a substrate in the range of 100~500g / m ² · Hr Is desirable. In particular, a preferable base material has a wet tensile strength of 1.0 kg / 15 in addition to the above requirements.
It is a water resistant paper having a thickness of at least mm, preferably at least 2.0 kg / 15 mm. The cut flower freshness retaining sheet obtained by the method of the present invention is not particularly limited in terms of constitution, but two typical examples are shown below. A structure in which a synthetic resin film is provided as a protective layer on the cut flower life-prolonging agent layer (a cross-sectional view of the structure is shown in FIG. 1). A structure in which an adhesive layer and a release sheet (also serving as a protective sheet) are laminated on a cut flower life-prolonging agent layer (a sectional view of the structure is shown in FIG. 2).

The manufacturing method according to the present invention, that is, the surface substrate 2
When the life prolonging agent layer 1 is applied to the life prolonging agent, the life prolonging agent has a pH of 2.5 to 3.
5, the use of an aqueous solution of aluminum sulfate adjusted to preferably 3.0 to 3.5 reduces the occurrence of rust in the guide roll of the coating device, the drying oven, or the processing step (winder, etc.), and It has been found that even if it adheres to a hand or the like, the roughness of the hand or the like is significantly reduced.

From the standpoint of life prolonging effect and ease of pH adjustment, it is most preferable to add sodium carbonate as a weakly acidic strong alkaline salt to an aqueous solution of aluminum sulfate. Application of the life prolonging agent thus prepared to the substrate is simple,
The coated sheet obtained did not curl, and the life-prolonging effect on cut flowers was almost the same level as when using aluminum sulfate alone. The obtained freshness-keeping sheet can be used as it is, but since the life-prolonging agent layer is exposed, there is a problem that the life-prolonging agent layer falls off from the surface base material during handling or processing. Therefore, the embodiment in which the protective layer is provided as described above is more preferable.

That is, since the cut flower life-prolonging agent layer is sandwiched between the surface base material and the protective layer, there is no concern that the life-prolonging agent layer directly touches the hands, etc., and it is hygienic and extremely easy to handle. .

The life prolonging agent in the present invention is, as described above, prepared by adding a weak acid strong alkali salt to aluminum sulfate. Particularly, a high-concentration aluminum sulfate aqueous solution (concentration = 27% by weight, pH = 2, viscosity = 20 c
The pH can easily be raised by adding sodium carbonate to ps). In the present invention, the pH of the life prolonging agent liquid is 2.5 to 3.5 using a weak acid strong alkali salt,
The desired effect can be obtained by adjusting the amount to preferably 3.0 to 3.5.

By the way, when the pH is less than 2.5, the effect of prolonging the life of cut flowers is not affected, but the effect of reducing the rusting of the metal part of the coating device and the roughness of the hands is small.
On the other hand, when the pH exceeds 3.5, the life-prolonging effect on cut flowers was considerably reduced. From the above, the pH of the life-prolonging agent coating liquid mainly composed of aluminum sulfate is 2.5 to
If it is adjusted to 3.5, especially 3.0 to 3.5 (equivalent to diluting a 27% by weight aluminum sulfate aqueous solution by 10 to 30 times), the concern about rust of the coating device is reduced.
Moreover, it was found that the life-prolonging effect was hardly affected. Further, when the thus prepared aqueous solution of life-prolonging agent was applied, almost no curling due to water of crystallization was observed when the solution was applied using a stock solution of aluminum sulfate (concentration = 27% by weight).

The reason why the effect is remarkable when sodium carbonate is added as a weak acid strong alkali salt is not clear, but the main cause is the generation of carbon dioxide gas by adding sodium carbonate to the aluminum sulfate aqueous solution. It is estimated to be. That is, when sodium carbonate is added to a high-concentration aluminum sulfate aqueous solution, carbon dioxide gas is generated, and a large amount of sodium carbonate is dissolved in the life-prolonging agent aqueous solution, resulting in a pH change.
Adjustment is extremely easy. Since the generated carbon dioxide gas goes out of the life prolonging agent aqueous solution phase, carbonate ions do not remain in the life prolonging agent aqueous solution, so that it is considered that the original life prolonging effect of aluminum sulfate is effectively maintained.

By the way, a weak acid strong alkali salt such as sodium borate is difficult to dissolve in a high-concentration aqueous solution of aluminum sulfate, and even if it is dissolved, borate ions and the like are eluted together with a life-prolonging agent in the water in which cut flowers are used to dissolve in the aqueous solution. It is thought that it will remain in the, and adversely affect the life prolonging effect.

Of course, in the present invention, coating is carried out using a commercially available basic aluminum compound (for example: basic aluminum sulfate) or an aluminum sulfate compound prepared by a general pH adjusting method (addition of sodium hydroxide). You can also However, the life-prolonging effect on cut flowers of the freshness-maintaining sheet obtained by these methods is compared with the sheet obtained by applying the pH-adjusted aluminum sulfate compound using sodium carbonate as a life-prolonging agent.
It was experimentally observed that the life-prolonging effect was low. In addition, when a general pH adjusting method, that is, when solid sodium hydroxide is added to a high-concentration aluminum sulfate aqueous solution, sodium hydroxide is hardly dissolved and it is difficult to obtain a satisfactory aqueous solution of life prolonging agent for coating. This is probably because the high concentration of aluminum sulfate (concentration = 27% by weight) was almost a saturated aqueous solution. Therefore, if a low-concentration aluminum sulfate aqueous solution is used, or if sodium hydroxide is made into an aqueous solution and added to the aluminum sulfate aqueous solution, p
Although H adjustment is possible, the concentration and viscosity of the obtained aqueous solution are greatly reduced, and to provide a life prolonging agent layer with a desired coating amount,
Since it is necessary to apply the resin over a large number of times, the productivity is remarkably reduced, and at the same time, the life prolonging effect is reduced, which is a problem.

Next, the preparation of an aqueous solution of life prolonging agent containing aluminum sulfate as a main component will be described with reference to specific examples.
That is, 100 parts by weight of a high-concentration aluminum sulfate aqueous solution (concentration = 27% by weight, PH = 2, viscosity = 20 cps),
When 10 parts by weight of solid sodium carbonate is added and stirred, carbon dioxide gas is generated, and the generation of carbon dioxide gas is stopped, and at the same time, a stable life prolonging agent aqueous solution (concentration = about 33% by weight, pH = 3,
A viscosity of 20 cps) is obtained. When the life-prolonging agent aqueous solution thus obtained is applied using a coating device so as to have a desired coating amount, the appearance is good and the porosity is irrelevant,
A flat sheet is obtained. Of course, a plurality of coatings can be performed relatively easily if necessary.

The life prolonging agent thus obtained has a pH higher than that of the aluminum sulfate stock solution, and there is no concern about rust of the coating apparatus or rough hands during the work. Also, unlike the case of applying a high-concentration aluminum sulfate aqueous solution, it is not necessary to consider various application conditions to control the application surface and curl control, and it is relatively easy to produce a freshness-preserving sheet with a good life-prolonging effect. can do.

A method for forming a life-prolonging agent layer on a surface substrate by using the aluminum sulfate life-prolonging agent aqueous solution whose pH is adjusted by the above-mentioned method will be specifically described below. First,
Applying pH-adjusted life-sustaining agent aqueous solution to one side of the surface base material,
Dry to form a film. In this case, in order for the freshness-preserving sheet of a predetermined size to exert an excellent life-prolonging effect on cut flowers, as a result of the experiment, the dry-application amount of the life-prolonging agent was 10 to 150.
It is desirable to adjust to the range of g / m ² (calculation assuming that the size of one sheet = 15 cm ² is effective). Incidentally, if it is less than 10 g / m ^2, it is difficult to obtain a desired life prolonging effect. On the other hand, if it exceeds 150 g / m ² , it is not preferable because the life prolonging agent is likely to cause chemical damage.

When the coating amount is as high as 150 g / m ² , it cannot be obtained by one coating, so that it can be obtained by a plurality of coatings. Also, as the coating device,
For example, an air knife coater, a roll coater, a bar coater, a slot die coater, etc. are used as appropriate.

As the life prolonging agent, other life prolonging agent may be appropriately used in combination with aluminum sulfate. Other life prolonging agents in this case include, for example, sugars such as sucrose and fructose,
Inorganic salts such as nitrates, calcium salts, magnesium salts, iron salts, potassium dihydrogen phosphate, primary potassium phosphate, aluminum salts, sodium salts, anions, cations,
Surfactants such as nonion, 8-hydroxyquinoline sulfate, sodium dichloroisocyanurate, boric acid, porcelain powder, benzoic acid, salicylsorbic acid, dihydroacetic acid, propionic acid, chlorous acid, hypochlorous acid, hexachlorophenpythiol Examples thereof include preservatives, fungicides and bactericides such as knoll and tribromosalicylanilide, ethylene gas inhibitors such as STS (silver thiosulfate), and plant hormone agents such as kinetin.

The freshness-retaining sheet obtained by the method of the present invention is a freshness-retaining sheet having many features by variously devising the surface base material 2 and further the protective layer 3 as its constituent members. Obtainable. Below, as a freshness retention sheet obtained by the method of the present invention,
Among the constituents, the constituents other than the life prolonging agent layer will be described in detail.

First, as the surface base material 2, for example, high quality paper, water resistant paper, art paper, coated paper, cast paper, metal foil paper, kraft paper, polyethylene laminated paper, impregnated paper, etc. Water-insoluble materials such as metal foil and synthetic paper, and synthetic resin films such as cellophane, soft polyvinyl chloride, hard polyvinyl chloride, polypropylene and polyethylene terephthalate are appropriately used.

However, when the aqueous solution of the life prolonging agent is directly applied to the surface of the surface base material, it is desirable to use a base material which is restricted to some extent in consideration of coating suitability and application suitability. That is, when the pH-adjusted life-prolonging agent aqueous solution as described above is applied to the surface base material, for example, when it is applied to ordinary high-quality paper and dried and dried, the life-prolonging agent layer becomes foamy and the life is prolonged when it becomes severe. There is a disadvantage that the agent layer easily peels off from the coated surface. On the other hand, when a film having chemical resistance, for example, a film such as polyethylene or polyethylene terephthalate is used as the surface substrate, the familiarity between the aqueous solution of aluminum sulfate and the film is poor and the adhesion between the two is poor, and satisfactory coating cannot be performed. However, there is also a problem that the printing method is restricted when printing is performed on it.

When a freshness-keeping sheet is finished by using a normal high-quality paper as a surface substrate, when the sheet is put into water to be used as a life prolonging agent sheet,
There is a problem that fine fibers of the surface base material float out in water and the water for use is easily contaminated with fiber waste. Such a phenomenon is particularly remarkable in the case of high-quality paper or the like having low water resistance and weak interlayer strength. In particular, when a transparent vase or the like is used, it gives an unpleasant feeling and is not preferable. Furthermore, there is a concern that contamination of the water will affect the cut edges of cut flowers and reduce the life-prolonging effect.

As described above, the surface base material 2 has coating suitability, excellent printability and workability, and does not change its shape when immersed in water for a long time. It is particularly preferable to use a material that can be easily processed thereafter and, of course, is as inexpensive as possible. The above-mentioned problems can be solved by using a paper having a specific wet tensile strength (having water resistance) of 1 kg / 15 mm or more and a paper having a water permeability of 1000 g / m ² · Hr or less.

That is, as the surface base material, the preferred material is J
According to IS-P-8135, by using a paper having a wet tensile strength of 1 kg / 15 mm or more, more preferably 2 kg / 15 mm or more after being immersed in water of about 20 ° C. for 1 hour, the above-mentioned problems Is eliminated. By the way, if a paper of less than 1 kg / 15 mm is used, when it is dipped in water, the peripheral parts of the paper will be easily broken easily with the passage of time, and some fine pulp fibers will float in the water to contaminate the water. There is a possibility. As a result, in particular,
If a transparent vase is used, its appearance will be significantly impaired.Furthermore, fine fibers in the water may contaminate the cut edges of the cut flowers, resulting in a diminished life-prolonging effect of the cut flowers. all right.

The water permeability is 1000 g / m ² · Hr
If a paper having a weight of 100 to 500 g / m ² · Hr is used, the life prolonging agent can be easily applied. By the way, when the water permeability exceeds 1000 g / m ² · Hr, the surface base material is excessively porous, and the life prolonging agent oozes out to the surface of the base material (the surface opposite to the coated surface), and a satisfactory product cannot be obtained. . In addition, the substrate is wavy after coating and drying, and satisfactory printing cannot be performed. On the other hand, in the case of a synthetic resin film having a water permeability of zero, the adhesiveness is poor and the life prolonging agent layer may fall off from the surface substrate.

Here, the water permeability is a value calculated as follows. That is, a transparent glass tube having a length of 150 mm opened vertically and an inner diameter of 17 mm and a wall thickness of 2 mm is prepared, and a measurement test piece (25 mmφ) is provided on one side of the glass tube so that water does not leak around the periphery. Adhesive (product name: Scotch strong adhesive (multipurpose) / Sumitomo 3M Limited). Separately, a glass tube having the same specifications is prepared, and a water-impermeable PET film (trade name: polyester film E5100 / 50μ / Toyobo Co., Ltd.) is brought into contact with one side of the glass tube, and the Scotch strong adhesive ( The thing which stuck the circumference was prepared using (multipurpose).

After the above preparation, a constant temperature and humidity chamber (20
(° C / RH 65% condition), each glass tube is fixed so that the open part faces upward, and then 10 g of distilled water is charged from the upper part of each glass tube. Then, the weight of each glass tube was measured immediately after charging and after 5 hours, and the reduced water amount was calculated by the following formula to obtain the water permeability T.
It was shown as (g / m ² · Hr).

T = [(A0-A1)-(B0-B1)] / 5πR ² R = inner diameter of glass tube (m) / 2 (= 0.0085 m) A0 = whole glass tube filled with a test piece Initial weight (g) A1 = weight of the entire water-filled glass tube with the test piece set after 5 hours (g) B0 = initial weight of the entire water-filled glass tube with the PET film (g) B1 = Weight (g) of the entire water-filled glass tube set with the PET film after 5 hours (however, B0-B1 indicates the amount of water evaporated from the upper open portion of the glass tube after 5 hours)

The method for obtaining a paper having a specific water permeability or a water-resistant paper having a specific wet strength as described above is not particularly limited, but it is not limited to wood pulp, hemp, bagasse, kenaf, bamboo and the like. Natural pulp such as wood pulp,
Furthermore, using non-wood pulp such as rayon and synthetic pulp,
The proportion and beating degree, the kind and the amount of the internal filler, the kind and the amount of the wet paper strength enhancer or the dry paper strength enhancer which is added as necessary, and further, the drying conditions are appropriately adjusted,
Obtained by making paper.

Further, in order to obtain a water resistant paper having a specific wet strength, various wet paper strength enhancers and the like are applied by an on-machine size press coating method in addition to the above-mentioned method of adding a paper strength enhancer. You can also get by method. Of course, the smoothing processing in the machine calender can be appropriately combined if necessary.

As the wet paper strength enhancer, general commercial products can be used as appropriate and are not particularly limited. Specific examples include those having an epoxy group such as polyamide-epichlorohydrin resin, polyamide-polyamine-epichlorohydrin resin and epoxidized polyamide resin, and further melamine-formaldehyde resin and urea-
A wet paper strength enhancer such as formaldehyde resin or polyethyleneimine is appropriately used.

As the dry paper strengthening agent, for example, a salt of acrylamide and an aminomethyl acrylamide copolymer, a quaternary ammonium salt, an acrylamide and a quaternary ammonium salt group-containing alkyl (meth) acrylate copolymer, acrylamide. And a polyacrylamide type such as sodium acrylate copolymer, a raw starch type, a modified starch type, a vegetable gum type and the like are also appropriately used.

The wet paper strength enhancer and the dry paper strength enhancer are generally used in an amount of about 0.2 to about 0.
It is adjusted in the range of about 1.5% by weight. Of course, a dry paper strength enhancer and a wet paper strength enhancer can be used in combination. Since the non-coated layer surface of the surface base material provided with the life prolonging agent layer is appropriately printed, it is not necessary to unnecessarily add chemicals to enhance the wet paper strength. Since excessive addition may cause poor printability and poor workability, a method in which the effect is as small as possible should be appropriately adopted.

Further, it is preferable to form a life prolonging agent layer on the surface base material 2 with as little binder as possible. When a binder such as starch or a synthetic polymer is used in combination, there is a concern that the binder may be eluted in the water in which the cut flowers are used, which may cause a blockage of the cut flower conduits and reduce the life prolonging effect.

The sheet for freshness preservation obtained by the method of the present invention does not require a protective layer as an essential requirement, but as an embodiment,
It is more preferable to provide a protective layer from the viewpoints of handling, prevention of falling of the life prolonging agent layer, safety and hygiene. The material and structure of the protective layer are not particularly limited, but may be one layer, multiple layers, or an adhesive finish structure as long as it has the function as described above. All those having functions other than the protective layer, such as the above, can also be the target.

Two typical embodiments of the freshness-keeping sheet obtained by the method of the present invention will be described below (FIGS. 1 and 2).
I will give you an explanation. That is, each of the products of FIGS. 1 and 2 is an embodiment example in which the cut flower life-prolonging agent layer 1 is sandwiched between the surface base material 2 and the protective layer 3. First, in the product of FIG. 1, the protective layer 3 is made of a synthetic resin layer, and the surface substrate 2 /
The product comprising the cut flower life-prolonging agent layer 1 / protective layer 3 is put into water as it is for use. The product name, usage, etc. of the product can be printed on the surface of the surface base material. The synthetic resin layer forming the protective layer 3 may be composed of one synthetic resin layer or plural synthetic resin layers (two layers), but the latter is generally the latter. preferable. Synthetic resin (layer) used for the protective layer 3
Include polyolefin resin, polyethylene resin, polypropylene resin, polyester resin and the like.

A laminating method is usually employed to form the protective layer 3 as a synthetic resin layer. Examples of the laminating method in this case include a wet laminating method, a dry laminating method, a hot melt laminating method, an extrusion laminating method, a solvent laminating method, and the like. Among them, the extrusion laminating method is preferable in the present invention. .

The protective layer 3 is formed on the back surface of the synthetic resin layer,
Water-resistant paper, high-quality paper, art paper, coated paper, metal foil paper, impregnated paper and other papers, polypropylene, polyethylene terephthalate and other films, metal foils, laminated paper and other supports may also be laminated. Good. Further, the back surface of the protective layer 3 may be printed. Of course, protective layer 3
As a substitute, various types of paper can be used instead of the synthetic resin (film). In that case, it is necessary to use an appropriate adhesive to bond the paper serving as the protective layer and the cut flower prolongation agent layer.

Next, FIG. 2 shows the case where the protective layer 3 is a combination of the pressure-sensitive adhesive layer 4 and the release sheet 5, and the pressure-sensitive adhesive layer 4 is in contact with the cut flower life-prolonging agent layer 1. In this product, the release sheet 5 is peeled off, and the laminate 6a composed of the surface substrate 2 / cut flower life-prolonging agent layer 1 / adhesive layer 4 is put into water for use. The pressure-sensitive adhesive layer 4 may be wound around the stem of a cut flower and put into water as it is for use.

The pressure-sensitive adhesive layer 4 is not particularly limited, but for example, acrylic, rubber-based, silicone-based, vinyl ether-based emulsion or various solvent or solventless pressure-sensitive adhesives can be used. From the viewpoint of price, it is desirable to use an acrylic emulsion adhesive.

The method for forming the pressure-sensitive adhesive layer is not particularly limited, but it is generally formed appropriately by any one of various coating methods. For example, a roll coater, an air knife coater, a bar coater, a slot die coater or the like which is generally publicly known and used can be used. The pressure-sensitive adhesive layer is preferably formed to a dry weight of about 5 to 50 g / m ² . By the way, if it is less than 5 g / m ² , the adhesive force may be weakened and it may be impractical. On the other hand, 50g
If it exceeds / m ² , the effect is saturated and the necessity is low from the economical aspect.

As the release sheet 5, a commercially available release sheet can be used. Further, if necessary, a release sheet can be prepared by coating a fluororesin or a silicone resin. For example, high-density base paper such as glassine paper, clay-coated paper, kraft paper, or laminated paper in which a resin such as polyethylene is laminated on high-quality paper is used, and a fluororesin or silicone resin is used in a dry weight of 0.05 to 3
A coating material having a peeling layer formed by thermal curing, ionizing radiation curing, or the like, which is applied so as to have a g / m ² level, is appropriately used.

The product shown in FIG. 1 and FIG.
The outline of the production using the adjusted cut flower prolongation agent aqueous solution containing aluminum sulfate as the main component will be described. In the product of FIG. 1, a cut flower life-prolonging agent aqueous solution having a predetermined concentration is applied to the surface of the base material 2 and dried to form a cut flower life-prolonging agent layer 1, and then the surface of the cut flower life-prolonging agent layer 1 is corona-discharged, It is manufactured by laminating a synthetic resin such as polyethylene by an extrusion laminating method to form the protective layer 3 made of a synthetic resin layer.

The product of FIG. 2 is similar to the product of FIG.
After forming the cut flower life-prolonging agent layer 1 on the surface of, the pressure-sensitive adhesive is separately applied to the release surface of the release sheet 5 to form the pressure-sensitive adhesive layer 4,
After drying, the cut flower life-prolonging agent layer 1 and the pressure-sensitive adhesive layer 4 are joined so as to face each other, and thus manufactured.

When the method for producing a freshness keeping sheet according to the present invention is used, aluminum sulfate (27
% Stock solution was directly applied to the surface base material to produce it, and it was possible to significantly improve the corrosion of the application device and the irritation of the worker's skin due to the life prolonging agent.
Further, the freshness-maintaining sheet obtained by the method of the present invention had almost the same level of life-prolonging effect as that obtained when aluminum sulfate alone was used as a life-prolonging agent for cut flowers.

[0056]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.
Unless otherwise specified, the concentrations and coating amounts of aluminum sulfate and the pressure-sensitive adhesive are all solids, and the other parts and% are parts by weight and% by weight, respectively. Further, since aluminum sulfate contains water of crystallization, the solid content is expressed (converted) as Al ₂ (SO ₄ ) ₃ in this example, as described above.

[Preparation of Cut Flower Life-Prolonging Agent Aqueous Solution] The cut flower life-prolonging agent aqueous solution used in the present invention was prepared as follows. (Life-prolonging agent aqueous solution 1) Aluminum sulfate aqueous solution (concentration = 2
7%, pH = 2, viscosity = 20 cps) To 100 parts of solid sodium carbonate, 3 parts of solid sodium carbonate was added and reacted to completely dissipate carbon dioxide gas, and an aqueous solution of aluminum sulfate life-prolonging agent (concentration: about 29%, pH = 2.6, viscosity = 20 cps) was obtained.

(Life-prolonging agent aqueous solution 2) Aluminum sulfate aqueous solution (concentration = 27%, pH = 2, viscosity = 20 cps) 10
Solid sodium carbonate (10 parts) was added to 0 part and reacted to completely dissipate carbon dioxide gas, and an aqueous solution of aluminum sulfate life-prolonging agent (concentration: about 33%, pH = 3, viscosity = 20 cp)
s) was obtained.

(Life-prolonging agent aqueous solution 3) Aluminum sulfate aqueous solution (concentration = 27%, pH = 2, viscosity = 20 cps) 10
Solid sodium carbonate (15 parts) was added to 0 part and reacted to completely dissipate carbon dioxide gas, and an aluminum sulfate life-prolonging agent aqueous solution (concentration: about 36%, pH = 3.4, viscosity = 20c) was added.
ps) was obtained.

(Life-prolonging agent aqueous solution 4) Aluminum sulfate aqueous solution (concentration = 27%, pH = 2, viscosity = 20 cps) 10
20 parts of solid sodium carbonate was added to 0 parts and reacted to completely dissipate carbon dioxide gas, and an aqueous solution of life-prolonging agent for aluminum sulfate (concentration about 39%, pH = 4.2, viscosity = 20c
ps) was obtained.

(Aqueous solution of life-prolonging agent 5) Aqueous solution of aluminum sulfate (concentration = 27%, pH = 2, viscosity = 20 cps) 10
30 parts of a 1N aqueous solution of sodium hydroxide was added to 0 parts, and an aluminum sulfate life-prolonging agent aqueous solution (concentration: about 22%, pH = 3,
Viscosity = 15 cps) was obtained.

[Preparation of Release Paper] A part of the glassine release paper used in the present invention was prepared by the following method. 15 parts of a commercially available silicone (trade name: KS-830E / Shin-Etsu Chemical Co., Ltd., silicone content concentration: 30%), 0.15 parts of a platinum-based catalyst, and 84.85 parts of toluene are mixed to prepare a silicone solution. Then, the solution was added to glassine base paper (70
g / m ² ) using a bar coater, coating amount is 1.0 g
By coating and drying so that / m ^2, to obtain a glassine release paper 1.

[Surface Base Material Used in Examples] The surface base material 2 used in the examples is label paper manufactured by Hokuetsu Paper Mills Ltd. (US tsubo: 80 g / m ² , wet tensile strength: 3.0 Kg /
15 mm, water permeability = 150 g / m ² · Hr).

[Adhesive used in Examples] The adhesive A used in Examples is an acrylic ester copolymer emulsion type adhesive (trade name: manufactured by Nippon Carbide Industry Co., Ltd.).
L-145).

Example 1 A sheet for keeping freshness of cut flowers having the structure shown in FIG. 1 was prepared.
That is, the life prolonging agent aqueous solution 2 was applied to one surface of the surface base material 2 for the first time by a bar coater so that the dry coating amount was 20 g / m ^2, and dried at 120 ° C. for 2 minutes. In addition, ² with a bar coater so that the total coating amount becomes 40 g / m 2.
The second coating was applied and dried at 120 ° C. for 2 minutes. While corona-discharging the surface of the life-prolonging agent layer provided in this way, a synthetic resin polyethylene (trade name: “SHO-REX L18
2 "manufactured by Showa Denko Co., Ltd.) was formed by an extrusion lamination method to form a protective layer 3 having a thickness of 20 μm to prepare a sheet for keeping the freshness of cut flowers.

Example 2 A sheet for maintaining the freshness of cut flowers having the structure shown in FIG. 1 was prepared in the same manner as in Example 1 except that the life prolonging agent aqueous solution 2 was changed to the life prolonging agent aqueous solution 1.

Example 3 A sheet for maintaining the freshness of cut flowers having the structure shown in FIG. 1 was obtained in the same manner as in Example 1 except that the life-prolonging agent aqueous solution 2 was changed to the life-prolonging agent aqueous solution 3.

Example 4 In Example 1, one side of the surface base material 2 was coated only once with a bar coater so that the coating amount after drying was 40 g / m ^2, and dried at 120 ° C. for 2 minutes. Others were the same as in Example 1 to obtain a sheet for keeping the freshness of cut flowers having the configuration shown in FIG.

Example 5 In Example 5, a freshness keeping sheet having the structure shown in FIG. 2 was prepared. That is, the cut flower life-prolonging agent layer 1 was formed on one surface of the surface base material 2 in the same manner as in Example 1. Separately, the amount of adhesive A applied is 25 g
/ M ² is applied to the release paper 1 to be the release sheet 5 to form the pressure-sensitive adhesive layer 4, and then the pressure-sensitive adhesive layer 4 and the cut flower life-prolonging agent layer 1 are attached to each other, Material 2
A cut flower freshness-maintaining sheet consisting of / cut flower life-prolonging agent layer 1 / adhesive layer 4 / release sheet 5 was obtained.

Comparative Example 1 A sheet for keeping freshness of cut flowers having the constitution shown in FIG. 1 was prepared.
That is, an aqueous solution of aluminum sulfate (concentrated
Degree = 27%, pH = 2, viscosity = 20cps)
The amount is 15g / m²The first time with a bar coater
It was applied and dried at 120 ° C. for 2 minutes. In addition, Barco
Total coat amount is 30 g / m ²So that
The second coating was applied and dried at 120 ° C. for 2 minutes. This
While corona discharging on the surface of the life-prolonging agent layer provided in this way,
Synthetic resin polyethylene (Product name: "SHOREX L1"
82 ", manufactured by Showa Denko KK)
Form the protective layer 3 with a thickness of 20 μm by the minate method.
A sheet for keeping the freshness of cut flowers was prepared.

Comparative Example 2 In Comparative Example 1, one side of the surface base material 2 was coated only once with a bar coater so that the coating amount after drying was 30 g / m ^2, and dried at 120 ° C. for 2 minutes. In the same manner as in Comparative Example 1 except for the above, a sheet for maintaining the freshness of cut flowers having the configuration shown in FIG. 1 was obtained.

Comparative Example 3 A cut flower freshness-keeping sheet having the structure shown in FIG. 1 was obtained in the same manner as in Example 1 except that the life-prolonging agent aqueous solution 2 was changed to the life-prolonging agent aqueous solution 4.

Comparative Example 4 A sheet for maintaining the freshness of cut flowers having the structure shown in FIG. 1 was obtained in the same manner as in Comparative Example 1 except that the aqueous solution of life-extending agent 5 was changed to the aqueous solution of aluminum sulfate.

Comparative Example 5 A life-prolonging effect evaluation test was carried out by the following method using only tap water, and the obtained results are shown in the table.

[Evaluation Test Method for Life-Prolonging Effect of Cut Flowers] The cut flowers used in the evaluation test are roses, spray carnations,
Chrysanthemum was used. Also, all cut flowers were grown in a greenhouse, and when the buds grew under normal growth conditions, cut out the ones that were in a perfect growing condition and cut them with scissors so that they would form a 30 ° angle with the stem in water. The cut flowers were tested. Into a 1 liter wide-mouthed bottle containing 500 ml of tap water, put 5 cut flowers of the same type and a sheet (3 cm x 5 cm) according to the present invention, observe the situation of cut flowers every day, until it is worth watching. The number of days is defined as the cut flower life, and the results are shown in Table 1.

[Rust Evaluation of Coater] In producing the sheet of the present invention, after the aqueous solution of life prolonging agent was applied (total application time: 150 Hrs), the rust condition of the guide roll of the coater and the oven was observed. ◯: No rust observed at all Δ: Slight rust observed ×: Many rust observed

[Hand Roughness] In the production of the sheet of the present invention, after applying the life prolonging agent aqueous solution, a coater worker was investigated to check the hand roughness. ◯: Rarely observed. Δ: Slightly rough. X: Roughness is observed and itching is felt.

[Curl] The coated sheet of the present invention is left in a thermostatic chamber (20 ° C., 65%) for 24 hours, and the curled state of the sheet is observed. ◯: Flat state Δ: There is curl, but there is no particular problem in practical use. ×: curl is severe and difficult to handle

[0079]

[Table 1]

[0080]

[Table 2]

[0081]

As is clear from the results shown in Tables 1 and 2, the manufacturing method according to the present invention is very simple and easy to work with. In addition, the sheet for keeping the freshness of cut flowers obtained by the production method was a sheet that could be used easily and safely, and had an excellent effect of extending the life of cut flowers.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a sheet for maintaining the freshness of cut flowers obtained by the method of the present invention.

FIG. 2 is a cross-sectional view showing an example of a sheet for maintaining the freshness of cut flowers obtained by the method of the present invention.

[Explanation of symbols]

1: Cut flower life-prolonging agent layer 2: Surface base material 3: Protective layer 4: Adhesive layer 5: Release sheet 6a: Laminate body composed of surface base material-cut flower life-prolonging agent layer-adhesive layer

Claims (3)

[Claims] 1. A method for producing a sheet for maintaining freshness of cut flowers, which comprises a surface base material and a cut flower prolongation agent layer containing aluminum sulfate as a main component, and an aqueous solution containing aluminum sulfate used for forming the cut flower prolongation agent layer. The method for producing a sheet for maintaining freshness of cut flowers, which comprises providing a cut flower life-prolonging agent layer using an aqueous solution in which a weak acid strong alkali salt is added so that the pH of the cut flower is 2.5 to 3.5. . 2. The method for producing a sheet for keeping the freshness of cut flowers according to claim 1, wherein the pH of the aqueous solution containing aluminum sulfate is adjusted to 3.0 to 3.5. 3. The method for producing a sheet for keeping the freshness of cut flowers according to claim 1, wherein the weakly acidic strong alkali salt is sodium carbonate.