JPH0352779B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a soft vinyl chloride resin film with improved adhesiveness. More specifically, when a soft vinyl chloride resin film is continuously produced, an anti-blocking agent is sprayed on at least one side of the film before the film is wound into a roll, thereby impairing the smoothness of the resulting film surface. Also, it relates to a method for producing a soft vinyl chloride resin film with improved tackiness, which does not impair the appearance and transparency of the resulting film even if the film sprayed with an anti-tack agent is recycled. It is. Soft vinyl chloride resin film, which is made by blending a large amount of plasticizer with vinyl chloride resin, is generally produced continuously by a calendar molding method, and the film is wound up into a roll and transported as a roll. Stored and traded. Soft vinyl chloride resin films have a wide variety of uses, including everyday goods, clothing, and covering agricultural greenhouses. and,
Depending on the intended use, the material is unwound from the roll, cut, and subjected to so-called secondary processing such as welding. Add 30PHR of plasticizer to the base vinyl chloride resin.
The soft vinyl chloride resin film formed into a film with the above blend exhibits adhesiveness on the film surface, and the surfaces of the film wound into a roll adhere to each other. Rolled films with surfaces that adhere to each other in this way are difficult to unwind during secondary processing, resulting in extremely poor workability and, in some cases, The surfaces of the products often stuck to each other, resulting in defective products. As a method to eliminate the above problem, a method has been proposed in which a soft vinyl chloride resin film is continuously manufactured and an anti-blocking agent such as starch or talc is sprayed on the surface of the film immediately before it is wound into a roll. , has been put into practical use. However, these starches, talc, etc. are not compatible with soft vinyl chloride resins, so if the scraps generated from films sprayed with these anti-blocking agents are recycled, they may become sticky or lose their transparency. Problems such as damage may occur. Therefore, the above method can only be applied to products where transparency is not important, such as colored products and opaque products. In addition, the soft vinyl chloride resin film used to cover agricultural greenhouses needs to transmit as much sunlight as possible into the greenhouse. Therefore, the anti-adhesive powder sprinkled on the surface of the film during film production will be removed from the surface of the film along with rainwater or water droplets generated inside the greenhouse within a short period of time after it is used to cover agricultural greenhouses. must be removed. From this perspective,
Soft vinyl chloride resin films used for covering agricultural greenhouses are often used during secondary processing without spraying anti-blocking agents such as starch during film production. In order to eliminate the above problems when performing secondary processing,
When a film is unwound from a roll, a method is used in which fine powder such as starch or talc is sprinkled on the surface of the unwound film. However, when dusting anti-adhesive powder such as starch or talc on the surface of the film, the fine powder not only scatters into the air and makes the working environment extremely bad, but also causes loss of fine powder. The problem is that it's big. In order to prevent the scattering of fine powder into the air, some secondary processing plants have adopted the method of using a dedicated fine powder spreader, but in most secondary processing plants, such a method is not used. It is not adopted and processing work is carried out under adverse conditions. Under such circumstances, there has been a demand for a soft vinyl chloride resin film that is free of stickiness and has better workability during secondary processing. Under such circumstances, the present inventors have found that the surface smoothness of the soft vinyl chloride resin film is not impaired, and even if the film is recycled, the appearance and transparency of the resulting film can be improved. The present invention has been completed as a result of extensive research aimed at providing a method for producing a soft vinyl chloride resin film that does not damage the film and has improved adhesiveness. However, the gist of the present invention is to form a resin composition containing 30 to 100 parts by weight of a plasticizer per 100 parts by weight of vinyl chloride resin into a film, and before winding this film into a roll, at least A method for producing a soft vinyl chloride resin film with improved tackiness, characterized in that tetrasilicon mica having an average particle diameter in the range of 3 to 20 microns is dispersed on one side. The present invention will be explained in detail below. In the present invention, the vinyl chloride resin refers to polyvinyl chloride and a copolymer mainly composed of vinyl chloride. Monomers copolymerizable with vinyl chloride include vinyl esters, vinyl ethers, acrylic acid or methacrylic acid and their esters, maleic acid or fumaric acid and their esters, maleic anhydride, aromatic vinyl compounds, Examples include halogenated vinylidene compounds, acrylonitrile, methacrylonitrile, ethylene, and propylene. To soften the above vinyl chloride resin, resin
30 to 80 parts by weight of plasticizer is added to 100 parts by weight. Examples of plasticizers that can be used include phthalate esters such as dioctyl phthalate, dibutyl phthalate, butylbenzyl phthalate, dibenzyl phthalate, diisodecyl phthalate, didodecyl phthalate, and diundecyl phthalate; dioctyl adipate, n-butyl adipate, Aliphatic dibasic acid esters such as dibutyl sebacate; glycol esters such as pentaerythritol ester and diethylene glycol benzoate; fatty acid esters such as methyl acetyl ricinoleate; phosphate esters such as tricresyl phosphate and triphenyl phosphate ;Epoxidized soybean oil,
Epoxidized oil such as epoxidized linseed oil; citric acid esters such as acetyl tributyl citrate, acetyl trioctyl citrate, tri-n-butyl citrate; trialkyl trimellitate,
Examples include plasticizers with various structures such as tetra-n-octyl promelitate, polypropylene adipate, and other polyester-based plasticizers. In addition to the above-mentioned plasticizers, the vinyl chloride resin may contain various usual resin additives, such as lubricants, as needed.
Antioxidants, ultraviolet absorbers, light stabilizers, dyes, pigments, fillers, flame retardants, etc. can be added. These resin additives can be selected in the usual amount, for example, within the range of 5 parts by weight or less per 100 parts by weight of the base vinyl chloride resin. To blend plasticizers and various resin additives into the base vinyl chloride resin, use conventional mixing and blending techniques such as a ribbon blender, Banbury mixer, super mixer, and other conventionally known blenders and mixers. Bye. In the method of the present invention, the vinyl chloride resin composition containing the plasticizer is formed into a film. To form a film from the vinyl chloride resin composition,
Techniques such as extrusion molding methods such as T-die method and inflation method, calender molding method, and casting method can be employed. The film is preferably wide and long, and its thickness is preferably selected from the range of 0.005 mm to 1 mm. In the method of the present invention, before the long film is wound into a roll, tetrasilicon mica having an average particle diameter in the range of 3 to 20 microns is sprinkled on at least one side of the film. This tetrasilicon mica powder adheres to the surface of a soft vinyl chloride resin film and has the function of preventing the film surfaces from adhering to each other. Or it swells and cleaves due to water droplets, becoming a fine scale-like powder with a thickness of 30 mm or less,
It is preferred because it exhibits the property of being easily removed from the film surface. According to the present invention, tetrasilicon mica was selected as the anti-blocking agent to be sprayed on at least one side of the film surface because its refractive index is similar to that of the soft vinyl chloride resin composition that is the base material. Since the refractive index of the two is similar, not only is it not noticeable even if tetrasilicon mica powder is attached to the surface of the film, but the film with this powder attached to the surface can be recycled and used to form a film, and the powder can be transferred inside the film. Even if it is mixed into the film, deterioration of the film appearance and transparency can be prevented. According to the present invention, the tetrasilicon mica powder sprinkled on at least one surface of the film has an average particle size in the range of 3 to 20 microns. If the average particle diameter is smaller than 3 microns, the particles tend to aggregate with each other, and when actually sprayed on the film surface, many particles will aggregate together, reaching several tens of microns in diameter, and sometimes forming large clumps. This is undesirable because when it is sprayed on the film surface, the smoothness of the film surface is impaired. If the average particle size is larger than 20 microns, even if the particles are evenly distributed over the film surface, the winding pressure during the process of winding the film into a roll and storing the film will embed the particles into the film surface, causing the film surface to become grainy (surface grained). This is undesirable because small irregularities are formed on the surface of the surface of the surface, resulting in a loss of smoothness and a significant decrease in commercial value. In the present invention, tetrasilicon mica is defined by the general formula (), that is, XYSi ₄ O ₁₀ F ₂ ... () (Here, X and Y are
Mg2.5, when X is Na2/3, Y is Mg2 1/3Li2/3,
When X is Na1/3, Y is selected from Mg2 2/3Li1/3. ). In order to prepare tetrasilicon mica having the above average particle diameter, the tetrasilicon mica made into a sol is dried by spray drying or other methods to form a solid, and if necessary, it is pulverized using a pulverizer. Pulverizers that can be used in this case include a gas jet mill, an impact crusher that crushes by impact force, etc., but are not limited to these examples. After pulverization, particles with an average particle size in the range of 3 to 2 microns can be classified by using an air classifier or by slurrying the tetrasilicon mica in a solvent that does not swell or cleave it. Any conventionally known powder classification method may be used. The tetrasilicon mica particles absorb moisture and swell,
Since it has the property of cleaving, if a film on which it has been sprinkled is stored for a long period of time, the particles may cleave and the film's ability to prevent adhesion between films may deteriorate. In order to prevent or suppress this change over time, it is preferable to coat the surface of the tetrasilicon mica particles with another substance. Preferred substances for coating the surfaces of tetrasilicon mica particles include silicone oil and fluorine compounds. Specific examples of silicone oils include silicone oils with a skeleton of siloxane bonds and silicon atoms containing methyl groups, phenyl groups, hydroxyl groups, etc., such as dimethylpolysiloxane, diphenylpolysiloxane, methylphenylpolysiloxane, dimethyl- Examples include methylphenylpolysiloxane, dimethyl-diphenylpolysiloxane, methylhydrodienepolysiloxane, but are not limited to these examples. Examples of the fluorine-based compound include oligomers of tetrafluoroethylene resin and fluorine compounds containing a perfluoroalkyl group having a functional group such as acrylate or methacrylate at the end. In order to coat the surface of the tetrasilicon mica particles with the above substance, the above silicone oil, fluorine compound, etc. are dispersed or dissolved in a solvent, the tetrasilicon mica particles are added thereto, mixed, and the solvent is evaporated. good. According to the present invention, the tetrasilicon mica powder is sprinkled on at least one surface of the film before the film is wound into a roll. The spraying method is
A method using a conventionally known device such as an electrostatic duster that utilizes electrostatic charging of particles or a spray machine that uses a rotating drum may be used. The amount of spraying on the film surface can be selected depending on the type of plasticizer mixed in the film, the amount of plasticizer mixed, the secondary processing method of the film, etc.
It is preferably in the range of 0.01gr/m ² to 1.5gr/m ² . If the spray amount is less than 0.01gr/ ^m2 , there will be little effect on preventing adhesion on the film surface, and 1.5gr/ ^m2
A larger amount is not preferable because the amount of spraying is too large and the fine powder is partially deposited on the film, impairing the smoothness of the film surface. A small amount of a conventionally known anti-blocking agent such as starch or talc may be mixed into the tetrasilicon mica powder to be sprinkled on the surface of the film. The mixing ratio in this case can be appropriately selected depending on the intended use of the film. After the tetrasilicon mica powder is sprinkled on the surface of the film, the film is wound up using a conventional film winding method such as a center winder, a surf S winder, etc. to form a roll-shaped product. The anti-adhesive soft vinyl chloride resin film thus obtained can be widely used as daily necessities, clothing, agricultural house coatings, and the like. The present invention has particularly remarkable effects as described below, and its industrial utility value is extremely large. (1) Since the soft vinyl chloride resin film obtained by the method of the present invention has tetrasilicon mica powder of a specific particle size sprinkled on the film surface, the tackiness of the film surface is significantly improved. Become. Therefore, even if this film is wound into a roll and stored for a long period of time, the film surfaces will not stick to each other, and the workability when performing secondary processing while unwinding the film wound into a roll is also improved. Often, the surfaces of secondary processed products do not stick to each other. (2) In the method of the present invention, tetrasilicon mica, which has a refractive index similar to that of the soft vinyl chloride resin composition, is made into powder with a specific particle size and used as an anti-blocking agent, which improves the transparency and surface smoothness of the film. Moreover, even if the film to which this powder is attached is recycled and used, the appearance and transparency of the film will not deteriorate. (3) It is preferable to treat the surface of the tetrasilicon mica powder with silicone oil or a fluorine-based compound before use, since it is possible to suppress the deterioration of the tetrasilicon mica powder over time. (4) The tetrasilicon mica powder used in the method of the present invention is
Since it has the property of swelling and cleaving with water, it can be easily removed from the film surface after secondary processing by wetting the film surface with water. Therefore, when the soft vinyl chloride resin film obtained by the method of the present invention is used as a covering material for agricultural greenhouses, etc., the powder adhering to the film surface swells and cleaves with rainwater and water droplets, resulting in a thickness of 30 mm or less. It becomes a fine scale-like powder and is washed away, improving the transparency of the film. Hereinafter, the present invention will be explained in detail based on Examples and Comparative Examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof. Examples 1 to 6, Comparative Examples 1 to 7 Polyvinyl chloride (=1400) 100 parts by weight of dioctyl phthalate Barium-zinc composite stabilizer as shown in Table 1 2 parts by weight of epoxidized soybean oil 3 Raw materials consisting of; The resin additives were weighed. Stir and mix these in a super mixer for 10 minutes at 165℃.
The mixture was kneaded on a heated roll, and then a transparent soft polyvinyl chloride film having a width of 1000 mm and a thickness of 0.05 mm was produced using an L-shaped calender. The film after it comes out of the calendar roll,
Bring the film temperature to 40°C by contacting it with a cooling roll.
Cooled below ℃. One side of this film was sprayed with various fine powders shown in Table 1 using a drum-type fine powder spray machine (Nitsuka Spray Equipment) at different amounts.
The spray was adjusted to 0.7 gr/m ² . (However, in Comparative Example 7, it was not sprayed.) This film was slit at 50 mm on both ends, recycled and made into a film, and finally a film with a width of 900 mm was made.
It was wound into a roll with a length of 1000 m. The 13 types of films wound into a roll were left in an atmosphere with a temperature of 40°C and a relative humidity of 90% for two weeks, and then the adhesiveness of the film was determined by the following method. Surface smoothness, transparency, and transparency after washing with water were evaluated. The results are shown in Table 1. "Adhesiveness"...Cut a 100cm square film from a roll, fold it into four, stack it on top of each other, apply a load of 30kg on top of it, leave it in an atmosphere maintained at 40℃ for 24 hours, and then remove the load. The state of adhesion between the film surfaces was observed when the film was unraveled. The evaluation results shown in Table 1 have the following meanings. ○: Almost no tackiness Δ: Slight tackiness ×: Significant tackiness "Surface smoothness": The surface of the film evaluated for tackiness above was observed with the naked eye. The evaluation results shown in Table 1 have the following meanings. ○...Surface is extremely smooth. △...Slight unevenness is observed on the surface. ×...Significant unevenness is observed on the surface. XX... Traces of powder clumping and falling are observed on the surface. "Transparency": A film cut from a roll was held up to a light source, and its transparency was determined visually. The evaluation results shown in Table 1 have the following meanings. ○...Good transparency △...Slightly poor transparency ×...Poor transparency "Transparency after washing"...After cutting a 50cm square film from a roll and immersing it in water at room temperature for 10 minutes The dried film was evaluated in the same manner as the "transparency" evaluation method above. The display of the evaluation results was also the same as above.

【table】

[Table] From Table 1, the following becomes clear. (1) The film obtained by the method of the present invention has significantly improved adhesiveness and has excellent film surface smoothness and transparency. (2) Even if recycled film is used by mixing it with virgin materials, the appearance and transparency of the film will not be adversely affected. (3) When conventionally known anti-blocking agents such as starch, talc, and magnesium carbonate are used, the smoothness of the film surface and the transparency of the film decrease. (4) If the average particle diameter of tetrasilicon mica is larger than 20 microns, the smoothness of the film surface will deteriorate.

Claims (1)

[Claims] 1. Plasticizer per 100 parts by weight of vinyl chloride resin
A resin composition containing 30 to 100 parts by weight is made into a film,
A soft vinyl chloride resin film with improved adhesion, characterized in that tetrasilicon mica with an average particle size in the range of 3 to 20 microns is sprinkled on at least one side of the film before the film is wound into a roll. manufacturing method. 2 A compound in which tetrasilicon mica is represented by the following formula (), that is, XYSi ₄ O ₁₀ F ₂ ... () (Here, X and Y are
Mg2.5, when X is Na2/3, Y is Mg2 1/3Li2/3,
When X is Na1/3, Y is selected from Mg2 2/3Li1/3. ) A method for producing a soft vinyl chloride resin film with improved tackiness according to claim 1. 3. Soft chloride with improved tackiness according to claims 1 and 2, characterized in that the tetrasilicon mica powder is surface-treated with silicone oil, a fluorine compound, etc. A method for producing vinyl resin film.