JP6181479B2 - Heat-resistant film manufacturing method and polybutylene terephthalate heat-resistant film - Google Patents

Description

The present invention relates to a method for producing a heat resistant film. More specifically, the present invention relates to a method for producing a crystalline thermoplastic resin film excellent in heat resistance, and a polybutylene terephthalate film excellent in heat resistance.

Conventionally, a decorative film is pasted on a base material made of a wood-based material such as wood, plywood, laminated board, particle board, or hard board. Moreover, in order to improve the three-dimensional feeling and texture of such a decorative plywood, a convex portion is provided on the decorative film by live-up printing. However, in order to perform boost printing, the film used as a printing substrate needs to have excellent heat resistance, and “use of a polyester resin typified by polyethylene terephthalate resin” has been proposed (for example, a patent Reference 1) was not sufficient. In addition, such a printing substrate is required to be colored in accordance with the design of the decorative film. However, a biaxially stretched film such as a polyethylene terephthalate-based biaxially stretched film has a manufacturing problem that it is difficult to handle a small lot. It was.

JP 2001-322222 A

The subject of this invention is providing the manufacturing method of the crystalline thermoplastic resin film excellent in heat resistance.

As a result of diligent research, the present inventor has continually held a crystalline thermoplastic resin film in a preheated preheating roll for a long time to promote secondary crystallization of the crystalline thermoplastic resin film. I found that I can achieve the task.

That is, this invention is a manufacturing method of a heat resistant film, Comprising: The process which hold | maintains a crystalline thermoplastic resin film continuously for 1.0 second or more to the preheating roll pre-heated at the temperature of 100-200 degreeC. It is the method of including. The present invention also provides a heat-resistant film which is a polybutylene terephthalate heat-resistant film and has a thermal deformation rate (α) at a temperature of 30 to 120 ° C. of −3.0 to 3.0%. To do.

By the method of the present invention, the heat resistance of the crystalline thermoplastic resin film can be greatly increased. Therefore, the heat-resistant film obtained by the method of the present invention can be suitably used as a base material for build-up printing. Moreover, since the method of the present invention can be carried out with a relatively simple apparatus, it can deal with small lots.

This invention is a manufacturing method of a heat resistant film, Comprising: The process of making a crystalline thermoplastic resin film continuously hold for 1.0 second or more to the preheating roll pre-heated at the temperature of 100-200 degreeC.

The crystalline thermoplastic resin film is embraced by the preheating roll and annealed to promote secondary crystallization, and for the annealing temperature, that is, a temperature equivalent to the preheating temperature of the preheating roll, You will be able to endure at least. Since heat resistance at least 100 ° C. is necessary to perform the build-up printing, the preheating temperature of the preheating roll is 100 ° C. or higher, preferably 110 ° C. or higher, more preferably 115 ° C. or higher. . On the other hand, from the viewpoint of cost and work safety, the preheating temperature of the preheating roll is 200 ° C. at most. Further, from the viewpoint of preventing molding trouble such as sticking of the film to a roll or the like, the preheating temperature of the preheating roll is preferably not higher than the melting start temperature of the crystalline thermoplastic resin film.

In the present invention, the melting start temperature of the crystalline thermoplastic resin film refers to a Diamond DSC type differential scanning calorimeter manufactured by PerkinElmer Japan Co., Ltd., held at 25 ° C. for 5 minutes, and 280 at 10 ° C./min. The temperature at the lowest temperature peak of the direct melting curve measured by a program that raises the temperature to ° C is the intersection of the baseline and the tangent of the inflection point of the melting curve on the melting start side, and the onset melting point Sometimes called.

The preheating roll is a roll whose surface is mirror-finished or satin-finished, and may be made of metal, ceramic, silicon rubber, or the like. Further, the surface of the preheating roll can be subjected to chrome plating, iron-phosphorus alloy plating, hard carbon treatment by PVD method or CVD method, etc. for the purpose of protection from corrosion and scratches.

The preheating roll can be preheated by any method. For example, it can be performed using steam, hot oil, electric heat, an infrared heater, or the like.

In addition, the crystalline thermoplastic resin film may be preheated before the crystalline thermoplastic resin film is held on the preheating roll. The method for preheating the crystalline thermoplastic resin film is arbitrary, and examples thereof include a method of winding around another preheating roll; a method of preheating in a non-contact manner using an infrared heater, a hot air blower, and the like.

When the pre-heating roll is allowed to hold the crystalline thermoplastic resin film (hereinafter, may be abbreviated as annealing time) continuously for 1.0 second or longer, sufficient secondary crystallization is achieved. As a result, heat resistance necessary for the build-up printing is imparted to the crystalline thermoplastic resin film. Preferably it is 1.5 seconds or more, More preferably, it is 2.0 seconds or more. On the other hand, the upper limit of the annealing time is determined from the viewpoint of the line speed (productivity), and although it depends on the radius and holding angle of the preheating roll, 10.0 seconds is sufficient.

The method for continuously setting the annealing time to 1.0 second or longer is arbitrary and is not limited. As a preferable method, for example, a method of increasing the radius of the preheating roll can be exemplified. Usually, the radius of the preheating roll is about 125 to 150 mm, but it is preferably 180 mm or more, more preferably 240 mm or more, and even more preferably 300 mm or more, thereby ensuring a sufficient annealing time even if the line speed is increased. can do. On the other hand, the upper limit of the radius of the preheating roll is not particularly limited, but is 1000 mm at most because of the cost of the apparatus.

As another preferable method, a method of increasing the holding angle (the angle from the point where the film touches the preheating roll to the point where the film is released from the preheating roll) can be given. Usually, the holding angle of the film in the preheating roll is about 90 to 120 degrees, but it is preferably 135 degrees or more, more preferably 180 degrees or more, and further preferably 225 degrees or more to increase the line speed. However, a sufficient annealing time can be secured. Further, in order to increase the holding angle, a touch roll or a feed roll may be used. On the other hand, the upper limit of the holding angle is 330 degrees at most due to physical limitations.

The thickness of the crystalline thermoplastic resin film is usually 10 to 500 μm, preferably 20 to 200 μm, more preferably 30 to 100 μm, for the purpose of imparting heat resistance by annealing.

The crystalline thermoplastic resin film may be a stretched film, but an unstretched film is preferable from the viewpoint of preventing troubles caused by heat shrinkage.

The crystalline thermoplastic resin film is not limited as long as it can be continuously held in a preheating roll preheated at a temperature of 100 to 200 ° C. for 1.0 second or longer. For example, films such as polyolefin resins such as polypropylene and poly-4-methylpentene-1; polyester resins such as polyethylene terephthalate and polybutylene terephthalate;

Of these, polybutylene terephthalate is preferred. Polybutylene terephthalate is a crystalline thermoplastic resin mainly composed of terephthalic acid and 1,4-butanediol. In recent years, some are produced using 1,4-butanediol derived from biomass raw materials and are commercially available. It is preferable to use such a biomass raw material resin when the biomass ratio of the biomass plastic defined by the Japan Organic Resource Association is 10% by mass or more because it becomes a target of the biomass mark. More preferably, it is 25% by mass or more, and is a target of the biomass plastic mark of the Japan Bioplastics Association.

The polybutylene terephthalate has a core-shell structure such as a polyester resin other than polybutylene terephthalate; a methacrylate ester / styrene / butadiene rubber graft copolymer, as long as the object of the present invention is not adversely affected. Rubber having: Pigment such as titanium oxide; inorganic filler, organic filler, resin filler; additive such as lubricant, antioxidant, weathering stabilizer, thermal stabilizer, mold release agent, antistatic agent, and surfactant May be included. The blending amount of these optional components is usually about 0.1 to 30 parts by mass when polybutylene terephthalate is 100 parts by mass.

The polybutylene terephthalate-based film is prepared by melt-kneading polybutylene terephthalate and the above-mentioned optional components used as desired using an arbitrary melt-kneader, pelletizing by an arbitrary method, and using, for example, a calendar processing machine. Alternatively, it can be obtained by forming into a film using an extruder and a T die or a spiral die. Alternatively, the melt-kneaded resin composition may be directly sent to a calendar processing machine, a T die, or a spiral die and formed into a film.

Examples of the melt kneader include batch kneaders such as a pressure kneader and a mixer; extrusion kneaders such as a co-rotating twin screw extruder and a different direction rotating twin screw extruder; and a calender roll kneader. These may be used in any combination. The pelletization can be performed by methods such as hot cut, strand cut, and underwater cut.

Any calendar processing machine can be used, for example, upright three rolls, upright four rolls, L four rolls, inverted L four rolls, and Z rolls. Can do. The said extruder can use arbitrary things, For example, a single screw extruder, the same direction rotation twin screw extruder, a different direction rotation twin screw extruder, etc. can be mention | raise | lifted. Any T die can be used, and examples thereof include a manifold die, a fishtail die, and a coat hanger die. Any spiral die can be used, and any of top blowing, bottom blowing, air cooling, and water cooling can be arbitrarily selected.

The polybutylene terephthalate heat-resistant film of the present invention is characterized in that the thermal deformation rate (α) at a temperature of 30 to 120 ° C. is −3.0 to 3.0%.

In this specification, the thermal deformation rate (α) at a temperature of 30 to 120 ° C. is a value measured in the following (A). Since the polybutylene terephthalate heat-resistant film of the present invention has an α value of −3.0 to 3.0%, it can be suitably used as a base material for boost printing. The α value is preferably −2.0 to 2.0%, more preferably −1.5 to 1.5%.

Moreover, since it uses suitably as a base material for live-up printing, the thickness of the said polybutylene terephthalate-type heat resistant film is 10-500 micrometers normally, Preferably it is 20-200 micrometers, More preferably, it is 30-100 micrometers.

As a method of obtaining the polybutylene terephthalate heat-resistant film of the present invention, a method of annealing a polybutylene terephthalate film obtained by an arbitrary method at a temperature of 100 to 200 ° C. can be mentioned, preferably a temperature of 100 And a step of continuously holding the polybutylene terephthalate film in a preheated roll preheated to ˜200 ° C. for 1.0 second or longer. More preferably, a first chill roll temperature of the above-described winding device is used, which includes an extruder, a T-die, a winding device, and a preheating roll, and is capable of continuously performing T-die extrusion film formation and annealing treatment. 70 ° C. or higher, preferably 80 ° C. or higher, more preferably 90 ° C. or higher to form a polybutylene terephthalate film; and the polybutylene terephthalate film obtained above is heated to a temperature of 100 ° C. or higher. Preferably, the above-mentioned preheating roll preheated to 110 ° C. or higher, more preferably 115 ° C. or higher, is continuously held for 1.0 second or longer. By doing as described above, the α value can be reduced. The upper limit of the first chill roll temperature is 200 ° C. or less, preferably 160 ° C. or less from the viewpoint of preventing molding troubles such as the film sticking to a roll or the like. In addition, the upper limit of the preheating roll temperature is 200 ° C. or less, preferably 160 ° C. or less, from the viewpoint of preventing molding troubles such as the film sticking to a roll or the like.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to this.

Measurement method (a) Thermal deformation rate Measured according to JIS K 7197: 1991. A thermomechanical analyzer (TMA) “Thermoplus 8310 (trade name)” manufactured by Rigaku Corporation was used. The test piece was 15 mm long and 5 mm wide, and the heat-resistant film was sampled so that the machine direction (MD) was the vertical direction of the test piece. The tensile stress was 400 mN, the distance between the initial chucks was 10 mm, and the temperature program was held at a temperature of 20 ° C. for 3 minutes, and then increased to a temperature of 200 ° C. at a rate of temperature increase of 5 ° C./min. From the obtained temperature-test piece length curve, the thermal deformation rate (α) was determined by the following equation.
α = (L1-L0) / L0 × 100 (1)
L1: Vertical length of the test piece when the temperature is 120 ° C. L0: Vertical length of the test piece when the temperature is 30 ° C.

(B) Heating dimensional change According to JIS K 7133: 1999, the rate of change after heating for 30 minutes at 120 ° C. was measured for each of the machine direction (MD) and the transverse direction (CD) of the heat-resistant film.

(C) Tensile properties In accordance with JIS K 7127: 1999, test piece type 5 was used as a test piece, and the test direction was 50 mm / min, respectively for the machine direction (MD) and the transverse direction (CD) of the heat resistant film. Tensile yield stress, tensile fracture stress, and tensile fracture strain were measured.

(D) Tear strength Measured according to JIS K 7128-3: 1998 under the conditions of a tensile speed of 50 mm / min for each of the case where the tear direction is the machine direction (MD) and the transverse direction (CD) of the heat resistant film. did.

(E) Impact strength measured according to ASTM D-1790 under the condition of -20 ° C. The number of fractures in 10 test pieces is shown in the table.

(F) According to 60 ° gloss JIS K 7105-1981, the metal roll (first chill roll) surface of the heat resistant film was measured.

Raw materials used (A) Polybutylene terephthalate (A-1) Polybutylene terephthalate “Torcon 1200S (trade name)” manufactured by Toray Industries, Inc., melting start temperature 212 ° C.
(B) Optional component (B-1) Titanium oxide (white pigment) “Taipeku CR-60-2 (trade name)” from Ishihara Sangyo Co., Ltd.

Example 1
A conceptual diagram of the apparatus used is shown in FIG. Extruder; T-die 3; Nip-type take-up device between metal roll 4 and rubber roll 5; Preheating roll 1 having a radius of 300 mm and a surface having a satin finish (number 300 mesh); T-die extrusion film forming and annealing treatment It is a device that can continuously. Feed rolls 6 to 8 are arranged so that the holding angle 2 of the preheating roll 1 is 250 degrees. Using a resin composition of 100 parts by mass of (A-1) and 20 parts by mass of (B-1), a film having a thickness of 50 μm is manufactured under the conditions of a T-die outlet resin temperature of 240 ° C. and a metal roll temperature of 90 ° C. Filmed. The surface in contact with the metal roll 4 during film formation is the measurement surface of the above test (f). The obtained film was continuously held in a preheating roll 1 preheated to a preheating temperature of 115 ° C. to obtain a heat resistant film. At this time, the line speed was 40 m / min. The above tests (a) to (f) were conducted. The results are shown in Table 1.

Examples 2 to 4, Comparative Examples 1 and 2
As shown in Table 1, one of the preheating temperature, the holding angle (the holding angle was changed by changing the position of the feed rolls 6 to 8), and the line speed were changed (the holding angle and the line The annealing time was changed along with the change in the speed. The results are shown in Table 1.

The heat-resistant film of the present invention has a small α value, and can be suitably used as a base material for build-up printing. On the other hand, in Comparative Example 1 in which the annealing time is shorter than the specified value and in Comparative Example 2 in which the preheating temperature is lower than the specified value, the α value is out of the specified range, and it is difficult to use it as a base material for live print.

1 is a conceptual diagram of an apparatus used in Example 1. FIG.

1: Preheating roll 2: Holding angle 3: T die 4: Metal roll (first chill roll)
5: Rubber roll 6: Feed roll 7: Feed roll 8: Feed roll 9: Film

Claims (7)

A method of manufacturing a heat-resistant film, the preheating roll preheated to a temperature 100 to 200 ° C., a crystalline thermoplastic resin film, the step of continuously embraced 1.0 seconds; see contains a
The method in which the biomass ratio of the biomass plastic defined by the Japan Organic Resource Association is 10% by mass or more for the crystalline thermoplastic resin film.
A method for producing a heat-resistant film, comprising a step of continuously holding a crystalline thermoplastic resin film for 1.0 second or more in a preheating roll preheated to a temperature of 100 to 200 ° C .;
Here, the crystalline thermoplastic resin film is a polybutylene terephthalate film.
A method of manufacturing a decorative film,
Producing a heat-resistant film by continuously holding a crystalline thermoplastic resin film in a preheated roll preheated to a temperature of 100 to 200 ° C. for 1.0 second or longer; and
Using the heat-resistant film produced in the above process;
Including methods.
A method for producing a heat-resistant film, comprising a step of continuously holding a crystalline thermoplastic resin film for 1.0 second or more in a preheating roll preheated to a temperature of 100 to 200 ° C .;
Here, the crystalline thermoplastic resin film is a polybutylene terephthalate film, and the biomass ratio of the biomass plastic defined by the Japan Organic Resource Association is 10% by mass or more.
A method of manufacturing a decorative film,
Producing a heat-resistant film by the method according to claim 1, 2 or 4 ;
Using the heat-resistant film produced in the above process;
Including methods.
The method according to any one of claims 1 to 5, wherein a holding angle of the crystalline thermoplastic resin film in the preheating roll is 135 degrees or more.
The method according to any one of claims 1 to 6, wherein a radius of the preheating roll is 180 mm or more.

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