JPS5869240A - Agricultural vinyl chloride resin film - Google Patents

Abstract

PURPOSE:To provide an agricultural vinyl chloride resin film exhibiting excellent non-tackiness between films, prepared by adding a specified amide compd. to a plasticizer-contg. vinyl chloride resin compsn. CONSTITUTION:At least one amide compd. selected from among N, N'-dioleyl adipamide. N, N'-distearyl adipamide and ethylene bislauryl amide is added to a vinyl chloride resin compsn. consisting of 100pts.wt. vinyl chloride resin and about 30-60pts.wt. liquid plasticizer (e.g. di-n-octylphthalate) and the mixt. is formed into a non-tacky agriculturual film of about 0.05-0.3mm. thickness. Heat insulating property of the film can be improved by the addition of inert solid particles which absorb infrared light with a wave length of 5-25mu and have a bulk density of 0.1g/cm<2> or higher, an average particle diametr of 0.5-10mu and a Mohs hardness of 4 or lower (e.g. powdered calcium carbonate having the above-specified bulk bensity and particle size).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an agricultural vinyl chloride resin film, and more specifically, an agricultural vinyl chloride resin film that is less likely to stick to each other when overlapped (has excellent non-adhesive properties). The present invention relates to a vinyl chloride resin film, and more particularly to an agricultural vinyl chloride resin film that is non-adhesive and has excellent heat retention properties.

In recent years, farmers cultivating useful plants have widely adopted methods of promoting the cultivation of useful plants in greenhouses or tunnels in order to increase profitability. As the covering material for this house or tunnel, vinyl chloride resin film, polyethylene film, ethylene-vinyl acetate copolymer film, polyethylene terephthalate film, etc. are used. Among them, soft vinyl chloride resin films have -
It is used the most because it has excellent weather resistance, transparency, heat retention, and strength.

Soft vinyl chloride resin film is soft and elastic, so it can be used in any shape of house or tunnel.
Although it has the advantage of being able to be spread easily, it has the disadvantage that it has a tendency to stick to each other when it overlaps (so-called adhesiveness), which is greater than that of polyethylene film or ethylene-vinyl acetate copolymer film. be. The film is very sticky.

Efficiency in extending work to greenhouses or tunnels decreases.

There is also a problem in that the work efficiency of bonding the films together using the high-frequency adhesive method is reduced, and that after being spread in the house or tunnel, the ventilation work in the house or tunnel and the work of opening and closing the house or tunnel are reduced.

Examples of cases in which soft vinyl chloride resin films exhibit the property of adhering to each other, that is, adhesion, are as follows.

(1) Adhesion at low temperatures A phenomenon observed when handling soft vinyl chloride resin films at relatively low temperatures below θC. In this case, no fusion phenomenon is observed.

(2) Adhesive at high temperatures When a soft vinyl chloride resin film is used as a covering material for a house or tunnel, the films may be stacked on top of each other outdoors to ventilate the inside of the house or tunnel.
It is often tied up in bundles and exposed to direct sunlight.

In this case, the film temperature rises to 9θ to 0°C. At such high temperatures, the films adhere to each other and in some cases fuse, and even if the temperature of the films falls, it takes considerable effort to separate the films from each other.

(3) Adhesion at high temperatures and in wet conditions This is the same phenomenon as in (2), but when stacked or bundled films are exposed to high temperatures while in a wet condition, moisture between the films increases. After evaporation, a severe adhesive phenomenon occurs.

Many techniques have been proposed in the past for eliminating the tackiness of such soft vinyl chloride resin films to make them exhibit non-adhesiveness (improving the non-adhesiveness), and some of them have been put to practical use.

Techniques for making agricultural vinyl chloride resin films exhibit non-adhesive properties include a method of blending various anti-blocking agents with the base vinyl chloride resin to form a film, and a method of blending inert solid fine particles to form a film. , and a method of combining both.

The method of forming a film by blending various anti-blocking agents with the base vinyl chloride resin has a problem in that it is difficult to improve the non-stick properties at low temperatures. The reason why a film containing an anti-adhesive agent exhibits an anti-adhesive effect is that the anti-adhesive agent is ejected onto the surface of the film. Adhesives are generally
It is difficult to spray out onto the film surface at low temperatures, and in order to exhibit non-stick properties even at low temperatures, the blending amount must be increased. If a large amount of anti-adhesive is added, the anti-adhesive will spray out more at high temperatures and the transparency of the film will decrease, and while it is being used as a covering material for a house or tunnel, dust will adhere to it, further reducing the transparency. The disadvantage is that the value decreases.

In a method of blending various inert solid fine particles to form a film and improving non-adhesion, the surface of the film is roughened by the inert solid fine particles. In order to roughen the film surface, it is necessary to increase the amount of inert solid fine particles added, which inevitably reduces the transparency of the film. This method can improve the non-stick properties of the film at low temperatures, but the non-stick properties at high temperatures can be improved.
It is not very effective in improving non-stick properties at high temperatures and in wet conditions.

As a method that combines both of these,
The methods described in Japanese Patent Application Laid-Open No. 069f and Japanese Patent Application Laid-Open No. 2006-069113 are proposed.

The method described in Japanese Patent Publication No. Shoj'l-301,9♂ is based on the basic composition for producing soft polyvinyl chloride film.
It is made into a film by blending a lubricant with a melting point of 6θC or higher and inert solid fine particles with a particle diameter of θ, θ~10 μm. However, a lubricant with a melting point of 6θC or higher and a particle size of 0.05~
In all of the above three cases where the film exhibits tackiness, the combined use of inert solid fine particles of 70 microns cannot exhibit the effect of improving non-tackiness.

Recently, agricultural vinyl chloride resin films are required not only to have the above-mentioned excellent non-adhesive properties but also to exhibit even better heat retention properties.

In order for agricultural vinyl chloride resin films to exhibit excellent heat retention properties, (a) during the day when sunlight is irradiating the film,
To be able to transmit sunlight into the tunnel or tunnel as much as possible. (b) To prevent the release of heat accumulated in the soil heated by sunlight as much as possible3. It is necessary to have two properties: (a) above
In order to satisfy property (b) above, the vinyl chloride resin film is required to be transparent, and in order to meet property (b) above, heat rays emitted from soil (5 microns to 25
Corresponds to wavelengths in the infrared region in the micron range. )of,
All you have to do is keep it out of the house or tunnel.

As a method for improving the heat retention of a synthetic resin film for covering a house or a tote/box, a technique described in Japanese Unexamined Patent Application Publication No. 1999-1973/9' has been proposed. In this method, inert solid fine particles having an ability to absorb in the infrared region are added to a synthetic resin film serving as a base. However, these conventional techniques have the following problems.

(1) When blending and mixing inert solid particles with synthetic resin raw materials, powdering of the solid particles is likely to occur, reducing the efficiency of blending and mixing.

(2) Furthermore, since the solid fine particles have a small bulk specific gravity, they are lightweight and bulky, and even if they are blended and mixed with the raw material synthetic resin, it is difficult to uniformly disperse the two.

(3) In order to improve the disadvantages of (1) and (2) above, if solid particles with a large particle size are used, the final film surface will become rough and pinholes will occur on the film surface. As a result, the tear strength of the film decreases. Furthermore, the transparency of the film also decreases.

(4) Inert solid fine particles generally have a high hardness, so they wear out and damage the mixer and film-forming machine during the process of blending and mixing with raw synthetic resin and forming a film. Metal powder gets mixed into the synthetic resin film,
The film may become discolored or have reduced weather resistance.

(5) In order for an agricultural synthetic resin film to exhibit heat retention properties, it is necessary to have properties (a) (transparency of the film) and properties (0) (heat retention), and (1)) In order to improve the properties of (a), inert solid fine powder particles are blended, but this is not preferred because the properties of (a) deteriorate. Further, with the prior art, it is difficult to prevent heat rays in the range of 25 microns from being emitted outside the entire range.

Under such circumstances, the present inventors have aimed to eliminate the problems of the film forming process in the prior art, provide an agricultural synthetic resin film with improved non-adhesiveness, and excellent quality. With the aim of providing a synthetic resin film for agricultural use with improved heat retention and excellent quality, the present invention was completed as a result of intensive studies.

Therefore, the first object of the present invention is to add N,N'-dioleyladipamide, N,N'-distearyladipamide, ethylenebis This is achieved by an agricultural vinyl chloride resin film that is formed into a film containing at least one kind of laurylamide.

Furthermore, the second object of the present invention is to add N,N'-, dioleyl adipamide, N, N'-distearyl adipamide, ethylene bis to a vinyl chloride resin composition containing a plasticizer. At least one type of laurylamide has absorption in the infrared region with wavelengths ranging from 5 microns to 25 microns, and has a bulk specific gravity of o, /l/CI! The film is made by blending inert solid particles with an average particle diameter in the range of 0.005 microns to 70 microns and a Mohs hardness of 9 or less, and has a straight light transmittance of 759b or more at the wavelength j Tatami microns. This is achieved by an agricultural polyvinyl chloride resin film characterized by the following.

The present invention will be explained in detail below.

In the present invention, the vinyl chloride resin refers to polyvinyl chloride, a copolymer mainly composed of vinyl chloride and a monomer copolymerizable with this; and a copolymer mainly composed of polyvinyl chloride,
This term also includes blends of this and other polymers and copolymers.

The film of the present invention is formed from a flexible blended vinyl chloride resin composition.

To obtain a soft blend, about 30 to 60 parts by weight of a liquid plasticizer is blended with 700 parts by weight of the vinyl chloride resin.

Preferred liquid plasticizers in the present invention include phthalic acid derivatives such as di-n-octyl phthalate, di-2-ethylhexyl phthalate, dibenzyl phthalate, diisodecyl phthalate, didodecyl phthalate, and diisodecyl phthalate; diisooctyl isophthalate; Isophthalic acid derivatives such as di-n-butyl adipate,
Adipic acid derivatives such as diocteradipate; di-n
- maleic acid derivatives such as butyl maleate; citric acid derivatives such as trilobyl citrate; itaconic acid derivatives such as monobutyl itaconate; oleic acid derivatives such as butyl oleate; ricinoleic acid derivatives such as glyceryl monolysyllate; Examples thereof include diyl phosphate, epoxidized Taidan oil, epoxy resin plasticizers, and the like.

In addition, before the film forming process, heat stabilizers, antistatic agents, antifogging agents, ultraviolet absorbers, etc. are added to the vinyl chloride resin as necessary.
Pigments, dyes, etc. can be added.

Heat stabilizers that can be blended include stearic acid, lead stearate, fatty alcohols, cal and rum stearate,
Examples include barium stearate, barium ricinoleate, dibutyltin dilaurate, dibutyltin simalate, etc. Antistatic agents or antifogging agents include nonionic surfactants, polyoxyethylene glycerin monostearate, etc. Examples of the absorbent include hydroquinone-based ultraviolet absorbers, salicylic acid-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, and benzo)IJ azole-based four-ray absorbers. Of course, these resin additives are not limited to those exemplified.

These resin additives are added in the usual amount, for example, resin IOθ
It is used in an amount of 5 parts by weight or less based on the weight of the fir.

The agricultural vinyl chloride resin film according to the present invention includes N,
At least one of N'-dioleylacifamide, N,N'-distearylazibamide, and ethylenebislaurylamide is blended and mixed. These additives function to provide the film with significant non-stick properties.

At least one of the above compounds is blended or mixed, if one of the three compounds is blended or mixed, one of the three compounds and another anti-adhesion compound are blended, When mixed, a combination of two or more of the above three types, two or more of the above three types,
Furthermore, combinations with other anti-blocking agents, etc. are included.

When using a combination of two or more of these anti-blocking agents, a compound with a melting point of 720'Q or less and a compound with a melting point of 1300'
It is preferable to combine the above compounds.

When two or more types are combined, the above combination is preferred because the film exhibits adhesive properties and can exhibit non-adhesive properties in all of the above three aspects. In other words, when two or more compounds with different melting points are used in combination, the compound with a higher melting point mainly exhibits (2) non-stickiness at high temperatures, and (3) non-stickiness at high temperatures and humidity. Non-stick properties in the state can be significantly improved. On the other hand, a compound with a low melting point can significantly improve (1) non-stick property at low temperatures among the three aspects in which the film exhibits stickiness.

If the amount of the above-mentioned compound added to the base vinyl chloride resin is too small, the non-adhesive property improving effect will not be exhibited, which is undesirable. On the other hand, if it is too large, the problem of °C spraying onto the film surface will occur, which is undesirable. The blending amount varies depending on the thickness of the film, but it is preferably O, OS to 8 parts by weight based on the base resin.

In order to achieve the second object of the present invention, in addition to blending the above-mentioned compound into the base vinyl chloride resin, inert solid particles are also blended.

These inert solid particles absorb in the infrared region with wavelengths ranging from 5 microns to 25 microns, and have a bulk specific gravity of o,
yt/crA or more, average particle size 0.5 micron to 7
The hardness is within the range of 0 microns and the Mohs hardness is 9 or less. These inert solid particles absorb heat rays with wavelengths in the infrared region ranging from 5 microns to 2j microns.
It not only prevents the film from being released outside the house, but also functions to improve the anti-stick properties of the film, especially, together with the above-mentioned compounds, the non-stick properties of the film at low temperatures.

If the bulk specific gravity of the inert solid particles is smaller than θ, //crA, they are lighter and bulkier than the vinyl chloride resin powder that is generally used as the base material, so they tend to cause dusting.
This is because the working efficiency during blending and mixing is reduced, and it becomes difficult to uniformly disperse the resin in the vinyl chloride resin base.

Furthermore, if the average particle size is O,S microns to 10 microns, it is difficult to roughen the film surface and the non-adhesive property improvement effect at low temperatures cannot be eliminated. This is because the transparency of the film decreases, pinholes are likely to occur on the film surface, and the strength decreases significantly. Next, the reason why the Mohs hardness is less than 9.9 g is because if the hardness exceeds 9, it will wear out and damage these devices during the mixing process with the base vinyl chloride resin and the process of forming the mixture into a film. This is because the metal powder mixed with the vinyl chloride resin film may cause problems such as coloring of the film and deterioration of weather resistance.

Specific examples of inert solid particles include feldspar, calcium carbonate, magnesium carbonate, magnesium silicate, talc, aluminum hydroxide, etc., but are limited to the exemplified ones as long as they meet the above requirements. The four inert solid particles absorb heat rays in the infrared region with wavelengths ranging from 5 microns to 25 microns, and prevent them from being emitted outside the world.
Since it is difficult for one type to satisfy this property, it is preferable to use two or more types in combination.

If the blending ratio of inert solid particles is too small, it will be difficult to roughen the film surface, and the non-adhesive property improvement effect at low temperatures will not be exhibited. On the other hand, if the amount is too large, the non-adhesive property can be improved at low temperatures, but the transparency of the film will be lowered (It is not preferable). Although it varies depending on the thickness etc., θ,
It is 70 parts by weight.

In order to blend and mix each of the above-mentioned additive components with the base vinyl chloride resin, use the usual blending and mixing techniques, such as a ribbon blender, kunnokuri mixer, and other compounding machines and mixers. be able to.

The agricultural vinyl chloride resin film according to the present invention is made by blending and mixing the above-mentioned additive components, and has a straight light transmittance of 7 sq6 or more at a wavelength of j5. If the straight light transmittance is less than 7s%, no.
This is because it is not suitable as a material for covering the wood.

The thickness of the agricultural vinyl chloride resin film according to the present invention is preferably 0.05 mm or more, since if it is too thin, the heat retention will not improve and pinholes will easily occur in the film.
The upper limit is preferably about 0.3101.

In order to manufacture the agricultural vinyl chloride resin film according to the present invention, ordinary film manufacturing methods such as calendar molding, extrusion molding, inflation molding, etc. can be appropriately employed.

The agricultural vinyl chloride resin film according to the present invention has the following characteristics, and its industrial utility value is extremely high.

■ The agricultural vinyl chloride resin film according to the present invention is
Because it contains specific compounds.

The non-stick properties of the film are significantly improved. In particular, when a compound with a low melting point and a compound with a high melting point are combined and blended, the non-adhesiveness of the film at low temperatures and the non-adhesive properties at high temperatures, high temperatures, and humidity are simultaneously improved.

■ The agricultural PVC resin film according to the second aspect of the present invention contains inert solid particles that absorb heat rays, so that the heat rays emitted from the soil are not released outside the greenhouse or tunnel. It has excellent heat retention.

■ The agricultural vinyl chloride resin film according to the second aspect of the present invention uses inert solid particles having a specific bulk specific gravity, so the film manufacturing efficiency does not decrease and the solid particles are dispersed. can also be made uniform.

■ Since the inert solid fine particles have a specific particle size, the agricultural vinyl chloride resin film according to the second aspect of the present invention not only has improved non-stick properties at low temperatures. , pinholes are less likely to occur on the film surface, and the film has excellent transparency and tear strength.

■ The agricultural vinyl chloride resin film according to the second aspect of the present invention uses inert solid particles having a specific hardness, so the molding machine is not worn out during the film manufacturing process. Undamaged, abrasion and damaged metal powder can cause the film to become colored.

Weather resistance will not deteriorate.

Hereinafter, the agricultural vinyl chloride resin film according to the present invention will be described in detail based on Examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof.

Example/~7, Comparative Example/~6 Polyvinyl chloride (I5=/4tθθ)...
...100 parts by weight dioctyl phthalate ...
・・・・・・・・・・・・・・・ ￥Event Tricresyl Phosphate ・・・・・・・・・・・・・・・J
p-epoxy resin stabilizer (product name KP-♂d)...
/〃Barium-zinc composite liquid stabilizer ・・・・・・・・・
・・・・・・／ 〃Barium stearate ・・・・・・
・・・・・・・・・・・・・・・θ6.2 〃Zinc stearate ・・・・・・・・・・・・・・・・・・・・・
...θ, Ri〃Sorbitan Monostearate ...
A resin composition consisting of .

After mixing each formulation with a super mixer for 70 minutes,
Knead on a mill roll heated to 0.10r
A film of trm thickness was prepared.

Table 1 shows the quality evaluation results for each film. The evaluation and judgment methods for these qualities were as follows.

(b) Spraying of additives after 6 months The film surface, which had been left in a room for 2 months, was lightly rubbed with a fingertip to judge. ``○'' indicates that there are almost no finger marks left on the surface, ``08'' indicates that finger marks are slightly observed, ``△'' indicates that finger marks are significantly observed, and ``△'' indicates that finger marks are significantly observed. was set as 1×.

(Middle) Two adhesive films of 3θT×/θ0rtrpn were stacked and pressed together with rubber rolls to eliminate air between the films and bring them into close contact. This tightly adhered film was placed in an oven set at a predetermined temperature (3θC, θC1!0C) and maintained at this temperature for 2 hours. The film is then removed from the oven and brought to room temperature. After being left for a minute, the two films were peeled off using a tensile tester and the peeling stress was measured.
When overlapping two films, moisture was added between the films, and the films were brought into close contact using the same procedure as above, and the peel stress was measured using the same procedure as above.

From Table 1, the following becomes clear.

(11) The agricultural vinyl chloride resin film according to the present invention has a small amount of additives ejected onto the film surface, and
Extremely good non-stick properties in both dry and wet conditions.

(2) On the other hand, in the case of a film that does not use an anti-blocking agent, the additives are less likely to be ejected onto the film surface, but the films stick to each other significantly (see Comparative Example 6).

(3) When a compound other than the essential compounds of the present invention is used as an anti-adhesive agent, a large amount of adhesive sprays onto the surface of the film, and the non-adhesive effect of the film is insufficient (Comparative Example/ ~j).

Example Z/3, Comparative Example 7/3 Polyvinyl chloride (P=/9tθθ)...
...700 parts by weight dioctyl phthalate ...
・・・・・・・・・・・・・・・・・・・Rij #tricresyl phosphate ・・・・・・・・・・・・・・・・・・
・j〃Epoxy resin stabilizer (product name Ep-♂2♂)
・・・／ 〃Barium-zinc composite liquid stabilizer ・・・・
・・・・・・・・・l 〃Barium stearate ・・・
・・・・・・・・・・・・・・・・・・ 0.2 parts by weight Zinc stearate ・・・・・・・・・・・・・・・・・・
・・・・・・θ, Ri〃Sorbitan Monostearate ・
A resin composition consisting of .

After stirring and mixing each formulation with a super mixer for 10 minutes,
Knead on a mill roll heated to /6°C. θja
A film of r thickness was prepared.

Table 2 shows the quality evaluation results for each film. The evaluation and judgment methods for these qualities were as follows.

(/RA) The presence or absence of powdery flesh [observed by K. Those with no powdery appearance [
It was rated as ○-1, and those in which dusting was observed were rated as "×".

B) An anti-blocking agent and inert solid particles were blended into a dispersible resin composition of inert solid particles, stirred and mixed in a super mixer, and a portion of the mixture was taken and visually evaluated. Almost a dispersion of inert solid particles.

If the dispersion was uniform, it was marked as "○", and if the dispersion was extremely non-uniform, it was marked as "x".

(e) Raw materials worn out from the molding equipment were stirred and mixed in a super mixer, and then a portion of the mixture kneaded on a mill roll was taken and qualitatively analyzed for metals using a conventional method.

Those in which metal derived from the molding equipment material was not detected were marked as "○J", and those in which metal was detected were marked as "×".

(f) Presence or absence of pinholes When visually observed, no pinholes were observed as ``○'', and those with pinholes observed as 1×''.

(g) Coloring status was observed with the naked eye. Those that were not colored were marked as "○", those that were colored were marked as "x", and the color tone was also written.

(a) Straight ray transmittance at mμ
Measurements were made using a spectrophotometer model 323.

(Male) Splashing of additives after 6 months Same as described in (a) in Examples 7-7.

(nu) Adhesiveness Same as described in (b) in Examples 1 to 7.

2) Heat retention Mie system - An open tunnel with a diameter of 2 m and a length of 2 m was established in a field in Shigun, and this tunnel was covered with each film.
The temperature inside the tunnel at night was measured at the center of the tunnel. The period of measurement is from 2θ day of month// of 1980/
For j days up to January 2nd, the temperature was determined every hour from 6:00 pm to 6:00 am the next day, and the daily average value was calculated by averaging the temperatures during this period. , and 3°, which is shown as the average temperature for j days. From Table 2, the following is clear.

(1) The agricultural vinyl chloride resin film according to the present invention has no trouble during film production, has excellent film quality, and exhibits excellent non-adhesion in a wide temperature range from room temperature to θC, Moreover, it also exhibits excellent heat retention (see Examples ♂ to 3).

(2) On the other hand, in order to improve the non-adhesiveness of the film, an anti-adhesive agent which is not essential in the present invention,
Products containing anti-stick agents with low melting points do not significantly improve non-stick properties at low temperatures (compared to comparative examples), and increasing the amount added improves non-stick properties at low temperatures, but the additive film Spraying on the surface gets worse (comparative example wa,
10).

(3) When adding inert solid fine particles in addition to the anti-blocking agent, if the bulk specific gravity of the particles is smaller than θ,/f/d, the film will become dusty and will not be uniformly dispersed in the film. Defects occur (Comparative Example 1/Reference)
. Furthermore, when inert solid fine particles with high Mohs' hardness are used, molding equipment is abraded and damaged (see Comparative Example 12). If inert solid fine particles having an average particle diameter of more than 10 microns are included, the film will have many pinholes, resulting in poor quality (see Comparative Example 3).

Applicant Mitsubishi Monsanto Chemicals Co., Ltd. Representative
Person Patent attorney - (1 other person)

Claims (1)

[Scope of Claims] (11) A vinyl chloride resin composition containing a plasticizer, N,N'-dioleylazibamide, N,N'-distearylazibamide, and ethylenebislaurylamide. A vinyl chloride resin film for agricultural use, characterized in that it is formed into a film by blending at least one of the above. At least one of amide, N,N'-distearyl adipamide, and ethylene bislauryl amide (1), which absorbs in the infrared region with wavelengths ranging from 5 microns to 25 microns, and has a bulk specific gravity of θ.
, /f/ cd1 or more, an average particle size in the range of 0.5 microns to 70 microns, and a Mohs hardness of 1 or less, formed into a film, and formed into a film.
An agricultural vinyl chloride resin film characterized by having a linear light transmittance of 75 coefficients or more in r millimicrons. (3) The agricultural vinyl chloride resin film according to claim (2), wherein the inert solid fine particles are talc.