JP2006341595A - Molding method and molding device of sheet for thermoforming - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a formation at low temperatures which have no influence to the design nature, and obtain a molded body without no wrinkle or the like. <P>SOLUTION: After a part containing a portion 2 to be die-molded of a thermoforming sheet 1 which is a laminate of one or more thermoplastic resin layers (A) and a decorative layer (B) is heated and plasticized within a temperature range of (Tg(A)-30)°C-(Tg(A)+10)°C to a glass transition temperature Tg(A) of the thermoplastic resin layer (A), the entire periphery of the portion 2 to be die-molded is held and fixed by using a pair of frame-like clamps 14, 24 from both surfaces of the sheet 1, and a part of a die 20 of one side is pressed on one surface of the heated and plasticized portion, by which the heated and plasticized portion is elongated between the die of one side and the frame-like clamp. Thereafter, a die 10 of the other side contacts the heated and plasticized portion from an opposite direction against the surface of the heated and plasticized portion on which the die of one side abuts. The molding is carried out by sandwiching the heated and plasticized portion by both dies 10, 20. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is a method for forming a laminated sheet having a decorative layer, such as a laminated sheet having a decorative layer, which is useful as a sheet that does not require an outer layer coating used for automobile-related members, construction-related members, home appliances, and the like. And a molding apparatus. In particular, the present invention relates to a forming method and a forming apparatus for a forming laminated sheet having a metallic or printing design.

In general, when a colored resin molded body is manufactured, there are a method of kneading a pigment into the resin itself, coloring it and molding it by injection molding or the like, and a method of spraying the molded body. For example, when a metallic design is required, a coating method is often used rather than a coloring method because of the difficulty of kneading metal pigments and the tendency of pigment flow to be noticeable. In the case of the coating method, the effect of surface protection can be expected by baking the coating film to crosslink the polymer component. In recent years, from the viewpoint of protecting the working environment against the discharge of volatile organic solvents and protecting the external environment, the use of water-based paints and powder paints instead of paints using volatile organic solvents has also been attempted. It has been. However, it is still difficult to express a metallic design by a solvent-free coating method.
On the other hand, the method of applying a complicated design such as printing on the surface of the molded body cannot be handled by the coloring method or the coating method.

  On the other hand, a method is known in which a colored sheet on which a moldable support resin layer is laminated is molded integrally with a resin molded body at the time of injection molding. According to this method, it is possible to produce a resin-molded member having a metallic or printing design without solvent.

Conventionally, a thermoforming sheet is formed by a vacuum forming method in which the thermoforming sheet is sufficiently thermoplasticized and then the sheet and the mold are formed in a vacuum state, or the sheet is pressed against the mold by air pressure. There are a pressure forming method for forming, a press forming method (match mold forming method) for forming by sandwiching between a concave mold and a convex mold. Although the press molding method is a mechanical shaping method, the mold reproducibility is good. However, since the sheet is drawn into the mold during molding, wrinkles are easily generated, and the elongation of the sheet is not uniform. Therefore, there was a problem that the obtained molded body was unevenly thickened.
In order to prevent such excessive stretching of the sheet for thermoforming, to maintain the sheet thickness and to reduce wrinkles, etc., for example, at the upper and lower point clamps, the boundary portions of the individual molds of a plurality of male and female molds, respectively. Then, after clamping and clamping the plasticized thermoplastic foamed resin sheet to the minimum, the male and female molds are closed and molding is performed (for example, see Patent Document 1), or the peripheral portion of the resin sheet is used as the resin sheet. The resin sheet is sandwiched between the upper and lower pressing plates with a slightly wider interval, and then the end of the resin sheet is released from the sheet clamper, and the plug is lowered to slide the peripheral edge of the resin sheet between the upper and lower pressing plates. A method of pressing down the resin sheet, then fixing the peripheral edge of the resin sheet with the upper and lower pressing plates, lowering the upper and lower pressing plates, and performing vacuum and / or pressure forming (for example, special Document 2 reference) are known.

  Any of these methods is effective when molding is performed after sufficiently plasticizing or softening the thermoforming sheet. The term “sufficiently plasticized or softened” as used herein specifically refers to a state after the heated thermoforming sheet is heated to the extent that it is drawn down, and is used at least for the thermoforming sheet. This represents a state after sufficiently applying heat of the glass transition temperature of the resin plus 20 ° C. or higher.

However, the above method cannot be applied to a molded sheet to which a high temperature cannot be applied. For example, as a sheet having a metallic design with high brightness, a laminated sheet having an ink film in which thin metal thin pieces are dispersed in a binder resin varnish and having excellent spreadability at the time of thermoforming is known (for example, The gloss of the metal thin film strip ink used in the sheet is lost due to high heat. In addition, since a laminated sheet having a print-like design uses a pigment for the printed layer, discoloration or the like may occur due to high temperature, and the resulting molded product may have uneven color or discoloration. Moreover, about a complicated design, there also exists a problem that a pattern will deform | transform by excessive elongation of the sheet | seat for thermoforming.
When the molding is performed at a low temperature, for example, near the Tg of the resin used for the thermoforming sheet in the above method, the design is maintained, but thermoforming becomes difficult. For example, in the method of Patent Document 1, an excessive force is applied between the partial clamp and the unclamped portion, and the sheet may be torn or a molded article obtained by drawing the sheet may be wrinkled. Further, in the method of Patent Document 2, since the sheet is not completely held, the mold does not follow the mold and the mold reproducibility is inferior. I can't get it.
Japanese Patent Laid-Open No. 06-226834 Japanese Patent Laid-Open No. 10-166436 JP 2002-46230 A

  It is an object of the present invention to obtain a molded body that can be molded at a low temperature that does not affect the design properties and that does not generate wrinkles.

  As a method of obtaining a molded article excellent in thermoformability while maintaining design properties, the present inventors have used a glass transition temperature of a thermoplastic resin used in a thermoforming sheet (herein, the glass transition temperature is Using dynamic viscoelasticity measurement measured according to JIS K7244-1 method, the mechanical attenuation measured under the measurement conditions of frequency 1 Hz, measurement start temperature 0 ° C., temperature increase rate 3 ° C./min is the maximum value. A temperature close to Tg), specifically, a part of the thermoforming sheet including a portion to be molded is glass of the thermoplastic resin layer (A). After heat plasticizing within the temperature range of (Tg (A) -30) ° C. to (Tg (A) +10) ° C. with respect to the transition temperature (Tg (A)) (the thermoforming sheet in this state is Partially plasticized but not flowing, viscoelastically storage modulus It is a state from the transition region that has started to fall slightly to the rubber region.) In a state where the entire circumference of the portion to be molded is sandwiched and fixed from both sides by using a pair of frame clamps, At least a part of the mold is pressed against the heat-plasticized part inside the frame-shaped clamp to extend the heat-plasticized part between the one mold and the frame-shaped clamp, and accordingly After that, the above-mentioned problem can be solved by bringing the other mold into contact with the heat plasticized portion and sandwiching and molding the heat plasticized portion between the one mold and the other mold. I found it.

That is, the present invention is a method of thermoforming a sheet for thermoforming obtained by laminating one or a plurality of thermoplastic resin layers (A) and a decorative layer (B) between a pair of molds,
According to JIS K7244-1 method, when dynamic viscoelasticity is measured under the measurement conditions of frequency 1 Hz, measurement start temperature 0 ° C., temperature increase rate 3 ° C./min, when the mechanical attenuation shows a maximum value. When the temperature is the glass transition temperature (Tg),
A part of the thermoforming sheet including a portion to be molded is taken as a glass transition temperature (Tg (A)) of the thermoplastic resin layer (A) (however, the thermoforming sheet is made of the thermoplastic resin layer (A). ) In a plurality of layers, the highest glass transition temperature of the plurality of thermoplastic resin layers (A) is defined as Tg (A)), with respect to (Tg (A) -30) ° C. to (Tg ( A) After heat plasticization within the temperature range of +10) ° C.,
The entire circumference of the portion to be molded of the thermoforming sheet is clamped and fixed from both sides of the thermoforming sheet using a pair of frame clamps,
By pressing a part of one mold against one surface of the heat plasticized part, the heat plasticized part is stretched between the one mold and the frame clamp,
After that, the other mold is brought into contact with the heat plasticized portion from the direction opposite to the surface of the heat plasticized portion with which the one mold contacts,
Provided is a thermoforming sheet molding method in which the thermoplasticized portion is sandwiched and molded by the one mold and the other mold.

In addition, the present invention is based on JIS K7244-1 method, and the dynamic attenuation is measured when dynamic viscoelasticity is measured under the measurement conditions of a frequency of 1 Hz, a measurement start temperature of 0 ° C., and a temperature increase rate of 3 ° C./min. When the temperature at which the maximum value is shown is the glass transition temperature (Tg),
A portion of the thermoplastic resin layer (A) including a portion to be mold-molded of one or more thermoplastic resin layers (A) and a decorative layer (B) is laminated on the glass of the thermoplastic resin layer (A). Transition temperature (Tg (A)) (However, when the thermoforming sheet has a plurality of the thermoplastic resin layers (A), the highest temperature among the glass transition temperatures of the plurality of thermoplastic resin layers (A) is Tg. (A)), after heat plasticizing within a temperature range of (Tg (A) -30) ° C. to (Tg (A) +10) ° C., the mold for the thermoforming sheet should be molded. It is a device that molds by contacting a pair of molds on both sides of the part,
A frame-like clamp that holds and fixes the entire periphery of the portion to be molded of the thermoforming sheet is provided around each die, and the frame-like clamp is relatively movable with respect to the die. A thermoforming sheet forming apparatus is provided.

  According to the molding method of the present invention, the thermoforming sheet is heat plasticized within a temperature range of (Tg (A) -30) ° C. to (Tg (A) +10) ° C. of Tg of the thermoplastic resin. In addition, since the entire circumference of the portion of the thermoforming sheet to be molded is sandwiched and fixed by the frame-shaped clamp, the metal is applied to the thermoforming sheet inside the frame-shaped clamp with the sheet firmly fixed. The mold can be pressed. This makes it possible to optimize (homogenize) the tension of the thermoforming sheet immediately before molding, thereby reducing wrinkles due to drawing of the sheet into a pair of molds and deterioration of design properties due to uneven spreading. Can be suppressed. Since the temperature during molding can be controlled by appropriately selecting the Tg of the thermoplastic resin used for the thermoforming sheet, it is possible to set the molding temperature according to the heat resistance of the pigment and ink used in the decorative layer. . Since the frame-shaped clamp is movable, the tension of the sheet can be optimized by holding and fixing the thermoforming sheet by the frame-shaped clamp after heat plasticization.

  Since the apparatus of the present invention can be molded at a low temperature, it is possible to obtain a molded body having a good design.

The present invention will be described below with reference to the drawings based on the best mode.
1 and 2 are schematic cross-sectional views illustrating a first embodiment of the molding method and molding apparatus of the present invention. Although the molding method differs between FIG. 1 and FIG. 2, the same molding apparatus is used.
1 and 2, reference numeral 1 represents a thermoforming sheet. The molding apparatus used in the present invention includes a convex mold 10 and a concave mold 20 as one match mold molding mold, fixing plates 13 and 23 to which the respective molds 10 and 20 are fixed, and a thermoforming sheet 1. A pair of frame clamps 14 and 24 for clamping and clamping the entire periphery of the portion 2 to be molded from both sides from both sides, and cylinders 16 and 26 as drive means for driving the frame clamp to the mold Is provided.

  As shown in FIG. 4, the convex mold 10 includes a convex main body 11 that contacts the thermoforming sheet 1 to shape the shape of the concave portion of the molded body, and a box 12 that houses the convex main body 11. A block 12 a (see FIGS. 1 and 2) is inserted between the back surface of the convex body 11 and the bottom surface of the box 12, and the box 12 is fixed to the fixing plate 13. The convex body 11 has a horizontal surface 11a provided on the outer peripheral portion, a top surface 11c provided at the center of the convex body 11, and a slope 11b connecting the horizontal surface 11a and the top surface 11c. 11b and the top surface 11c are in a position higher than the horizontal surface 11a. In order to adjust the temperature of the mold, the convex mold 10 is provided with a flow path (not shown) of a medium such as water or oil, and can be connected to a mold temperature controller. The temperature control method for the mold is not particularly limited, and other methods may be used. An air vent hole or a vacuum hole (not shown) may be provided at the joint between the horizontal surface 11a and the slope 11b of the convex mold 10 as necessary. These holes are preferably as small as possible so that no trace remains on the molded body. Specifically, the diameter of the hole is preferably in the range of 0.3 to 1.2 mm, more preferably in the range of 0.3 to 0.6 mm.

  A frame clamp 14 is provided around the convex mold 10. A pair of overhanging portions 14a project outward from both sides of the frame-shaped clamp 14, and the tip of a drive shaft (rod) 16a of the cylinder 16 is fixed to the overhanging portion 14a. Thereby, the frame-shaped clamp 14 is configured to be relatively movable with respect to the convex mold 10. 4A shows a state in which the frame-shaped clamp 14 is lowered with respect to the convex mold 10, and FIG. 4B shows a state in which the frame-shaped clamp 14 is raised with respect to the convex mold 10. The cylinder 16 that drives the frame clamp 14 is fixed to a fixed plate 13 that is common to the box 12 of the convex mold 10. For this reason, both the convex mold 10 and the frame-shaped clamp 14 can be simultaneously approached and moved away from the thermoforming sheet 1 by driving the fixing plate 13 by a driving means (not shown).

As shown in FIG. 5, the concave mold 20 includes a concave mold body 21 that contacts the thermoforming sheet 1 and molds the shape of the convex portion of the molded body, and a box 22 that houses the concave mold body 21. A block 22 a (see FIGS. 1 and 2) is inserted between the back surface of the concave body 21 and the bottom surface of the box 22, and the box 22 is fixed to the fixing plate 23. The concave body 21 has a horizontal surface 21a provided on the outer periphery, a bottom surface 21c provided in the center of the concave body 21, and a slope 21b connecting the horizontal surface 21a and the bottom surface 21c. The slope 21b and the bottom surface 21c. Is at a position lower than the horizontal plane 21a. The concave mold 20 is provided with a flow path (not shown) for a medium such as water or oil in order to adjust the temperature of the mold, and can be connected to a mold temperature controller. The temperature control method for the mold is not particularly limited, and other methods may be used.
An air vent hole or a vacuum hole (not shown) may be provided at the joint between the slope 21b and the bottom surface 21c of the concave mold 20 as necessary. These holes are preferably as small as possible so that no trace remains on the molded body. Specifically, the diameter of the hole is preferably in the range of 0.3 to 1.2 mm, more preferably in the range of 0.3 to 0.6 mm.

  A frame-shaped clamp 24 is provided around the concave mold 20. A pair of overhanging portions 24a project outward from both sides of the frame-shaped clamp 24, and the tip of a drive shaft (rod) 26a of the cylinder 26 is fixed to the overhanging portion 24a. Thereby, the frame-shaped clamp 24 is configured to be movable relative to the concave mold 20. 5A shows a state in which the frame-shaped clamp 24 is lowered with respect to the concave mold 20, and FIG. 5B shows a state in which the frame-shaped clamp 24 is raised with respect to the concave mold 20. The cylinder 26 that drives the frame clamp 24 is fixed to a fixed plate 23 that is common to the box 22 of the concave mold 20. For this reason, by driving the fixing plate 23 by a driving means (not shown), both the concave mold 20 and the frame-shaped clamp 24 can be simultaneously approached and moved away from the thermoforming sheet 1.

In the match mold molding, the surface shape of the convex mold 10 and the surface shape of the concave mold 20 are the same. However, the clearance between the two molds when the convex mold 10 and the concave mold 20 are combined needs to be appropriately adjusted in consideration of the thickness of the thermoforming sheet 1 to be used and the expansion rate during thermoforming. Specifically, the clearance between the convex mold 10 and the concave mold 20 is preferably in the range of −50 to + 30% with respect to the thickness distribution of the actually obtained three-dimensional molded body, and more preferably −30 It is better to design within a range of ~ 10%. If the clearance between the molds is too large, the sheet cannot be sandwiched between the two molds at the time of thermoforming, the mold reproducibility of the resulting molded body is deteriorated, and deformation of the molded body is increased due to cooling unevenness. Conversely, if the clearance is too small, compression marks and vacuum hole marks are likely to remain on the molded body. In particular, when a decorative sheet having design properties is used as the thermoforming sheet 1, by making the clearance appropriate, a change in design properties at the time of molding is reduced, and a molded article having the desired design properties is obtained. It becomes easy.
Further, when the mold is heated and used, it is necessary to perform mold design (particularly clearance adjustment) in consideration of the coefficient of thermal expansion of the mold.

  In the present invention, the specific shapes and dimensions of the molds 10 and 20 can be appropriately designed according to the shape and dimensions of the molded body, and depend on the thermoformability of the thermoforming sheet 1, and thus are particularly limited. Although not intended, in order to obtain a three-dimensional molded body having sufficient mold reproducibility, the R value of the corner portion of the mold is 0.2 mm or more, the development rate is within 500%, the maximum drawing ratio (maximum high (The minimum length of the bottom / bottom) is preferably 1.5 or less and the maximum inclination angle is within 87 °. More preferably, the R value of the corner portion is 0.5 mm or more, the development rate is within 350%, the maximum aperture ratio is 1.0 or less, and the maximum inclination angle is within 85 °.

  In the present invention, in addition to the convex mold 10 and the concave mold 20 for molding the thermoforming sheet 1, the movable frame-shaped clamps 14 and 24 are used in combination, which is a problem unique to match molding. Generation | occurrence | production (this generate | occur | produces by the sheet drawing in in a metal mold | die) can be suppressed effectively. Moreover, generation | occurrence | production of the molding flaw by the sheet slack at the time of low temperature shaping | molding can also be suppressed simultaneously.

Since the movable frame clamps 14 and 24 are movable, the sheet 1 can be clamped and fixed after heating, so that the thermoforming sheet 1 can be strongly fixed, and the sheet into the molds 10 and 20 can be fixed. It is possible to remarkably suppress molding wrinkles due to pulling of 1. In general-purpose continuous molding machines, there are few cases where a frame clamp is used as a sheet fixing method at the time of heating, and even when a frame clamp is used, the sheet is clamped before heating. It was insufficient. In addition, the sheet for thermoforming 1 generally has a problem that the sheet is easily loosened due to thermal expansion below the glass transition temperature of the thermoplastic resin layer (A), and molding wrinkles occur due to this loosening. If the movable frame-shaped clamps 14 and 24 which are characteristic elements of the above are used, the heated thermoforming sheet 1 is pressed against the convex mold 10 or the concave mold 20 while being held by the frame-shaped clamps 14 and 24. The wrinkles in front (before fitting the concave mold 20 and the convex mold 10) can be removed.
The structure of the movable frame clamps 14 and 24 is preferably a shape that can fix the sheet 1 after heating and does not collide with the convex mold 10 and the concave mold 20 when moving. Specifically, the distance between the movable frame clamps 14 and 24 and the boxes 12 and 22 (the convex mold 10 and the concave mold 20 when there is no box) depends on the properties and thickness of the sheet, but is not limited. Since the previous wrinkles can be effectively suppressed, it is preferably within the range of 20 mm or less than the sheet thickness.

As shown in FIG. 7, for example, the frame-shaped clamps 14 and 24 have a combination of a convex portion 31 and a concave portion 32 on the surface of the sheet fixing portions 15 and 25 for sandwiching and fixing the thermoforming sheet 1. It is preferable to have. Thereby, when the sheet | seat 1 for thermoforming is clamped and fixed between both frame-shaped clamps 14 and 24, the convex part 31 protrudingly provided by one frame-shaped clamp is recessed part 32 recessedly provided by the other frame-shaped clamp. The thermoforming sheet 1 can be fixed more strongly. As a method of combining the convex portion 31 and the concave portion 32, the convex portion 31 may be provided with the convex portion 31 and the concave side frame clamp 24 may be provided with the concave portion 32. Conversely, the convex side frame clamp 14 may be provided. The concave portion 32 and the concave side frame clamp 24 may be provided with the convex portion 31, or these may be used in combination.
The shape of the convex part 31 and the recessed part 32 is not specifically limited, As the convex part 31, various shapes, such as pin shape, rib shape, serrated shape, mountain shape, triangular shape, column shape, are employable. Further, as the recess 32, various shapes such as a groove, a hole having a bottom, and a through hole can be adopted. At the time of clamping, a form in which the thermoforming sheet 1 is sandwiched between the convex part 31 and the concave part 32 may be used, or a form in which the thermoforming sheet 1 is broken and opened.

The movable direction of the frame clamps 14 and 24 is not particularly limited, but the vertical direction perpendicular to the horizontal surfaces 11a and 21a of the molds 10 and 20 is due to the pressure with which the tension of the sheet 1 is brought into contact with the molds. It is possible to adjust, and the molding wrinkles can be effectively suppressed, and it is preferable from the viewpoint of cost. Further, the power for moving the frame clamps 14 and 24 is not particularly limited, but a method using cylinders 16 and 26 using pneumatic pressure or hydraulic pressure is preferable because it is simple, and in particular, a pneumatic cylinder (hereinafter referred to as an air cylinder). Is preferable because the execution speed is faster. Moreover, when using a cylinder, since the clamping force of a sheet | seat becomes uniform, it is preferable to use 2 or more cylinders, and 4 or more uses are more preferable.
The clamping force for fixing the molding sheet using the frame-shaped clamps 14 and 24 is not limited because it depends on the properties of the thermoforming sheet 1 and the shape of the frame-shaped clamp, but the sheet is drawn into the mold during match molding. Since the defect due to wrinkles can be satisfactorily suppressed, 5 kgf {about 50 N} or more is preferable. Further, the clamping stress is preferably 0.05 kgf / cm ² {about 5 kPa} or more.
The materials of the molds 10 and 20 and the movable frame clamps 14 and 24 of the present invention are not particularly limited, and various metals that are conventionally used in molds for match molding can be used. Specific examples include aluminum-based steel materials, iron-based steel materials, thermosetting resins, and the like. In particular, a hard aluminum steel material is preferable as a material for the mold. If necessary, surface treatment such as polishing treatment, fluororesin treatment, alumite treatment, nitriding treatment, boriding treatment, plating treatment, etc. can be performed.

The match mold molding die and molding method according to the present invention can be used in various molding machines equipped with a sheet heating device, a lower mold movable device, and an upper mold movable device. A molding machine (with a plug mechanism) or a vacuum / pressure forming machine is preferred. As the sheet heating device, an indirect heating method from one side or both sides of the sheet is preferable because no trace of the heating device remains on the sheet surface. Moreover, since various molding methods are possible, it is preferable that a vacuum mechanism is provided in at least one of the lower mold movable device and the upper mold movable device. One of the movable devices having a vacuum mechanism may be provided with a pressure air mechanism. Moreover, the drive system of a lower mold | type movable apparatus and an upper mold | type movable apparatus is not specifically limited, An air cylinder type, a hydraulic cylinder type, a servo motor type, etc. can be used. However, although the mold closing force of the lower mold and the upper mold depends on the properties of the thermoforming sheet 1 and the mold shape, it usually requires 10 kgf {about 100 N} or more, and the mold reproducibility is good. 100 kgf or more {about 1 kN or more}. The mold closing stress is preferably 0.05 kgf / cm ² {about 5 kPa} or more. In addition, the mold closing force said here shows the maximum compressive force at the time of fitting a concave mold | type and a convex mold | type. Specifically, the thrust is obtained by subtracting the larger maximum thrust of the concave and convex movable frame clamps from the smaller maximum thrust of the lower mold movable device and the upper mold movable device.
That is, if the molding apparatus of the present invention is used, the sheet clamping force and molding speed can be adjusted by adjusting the thrust of the lower mold movable apparatus, the upper mold movable apparatus, the concave movable frame clamp, and the convex movable frame clamp. The mold closing force can be freely selected. For example, if the thrust of the movable frame clamp is increased, the clamping force of the sheet is high, the forming speed is slow, and the mold closing force is low. Conversely, if the thrust of the movable frame clamp is decreased, the clamping force of the sheet is reduced. Is low, the molding speed is fast, and the mold closing force is high.

As the molding method according to the present invention, it is preferable to use match mold molding according to the following procedures (1) to (9).
(1) The thermoforming sheet 1 is fixed with a clamp (not shown) attached to the molding machine.
(2) The heater (not shown) is moved to a position above and / or below the sheet 1.
(3) The sheet 1 is heated with the heater until a predetermined temperature is reached.
The predetermined temperature here is preferably a temperature at which the designability of the thermoforming sheet to be used is maintained. For example, the thermoforming sheet to be used has at least a thermoplastic resin layer (A) and a decorative layer ( B), and when the glass transition temperature of the thermoplastic resin layer (A) is expressed as (Tg (A)), (Tg (A) -30) ° C. to (Tg (A)) It is preferably within a temperature range of +10) ° C. Moreover, although the heating part of a sheet | seat is a part which should be mold-formed at least, generally it is preferable to heat uniformly to the frame-shaped clamp part of a sheet | seat.
(4) The heater is moved out of the molding machine.
(4 ′) When the heating position and the molding position are different, the heated sheet is moved to the mold position.
(5) The concave mold 20 arranged on the upper side of the sheet 1 is lowered, and the convex mold 10 arranged on the lower side of the sheet 1 is raised.
(6) After the thermoforming sheet 1 is clamped and fixed by the frame clamps 14 and 24 from both sides, the sheet 1 is sandwiched between the concave mold 20 and the convex mold 10 by using the lowering of the concave mold 20 and the rising of the convex mold 10. In a three-dimensional shape,
(7) The sheet 1 is held between the concave mold 20 and the convex mold 10 and held for a predetermined time.
(8) After raising the concave mold 20 and lowering the convex mold 10 to separate the molded body having a three-dimensional shape from both the molds 10 and 20 and both frame clamps 14 and 24, the molded body is predetermined with air or the like. Cool for hours.
(9) Open the clamp attached to the molding machine.

In (6), when the sheet is clamped and fixed, it is preferable that the sheet is not in contact with the mold because the sheet elongation tends to be uniform.
In (2) to (4), the height of the frame clamps 14, 24 is adjusted manually or by operating the solenoid valve to move the cylinders 16, 26 up and down, and the frame clamps 14, 24 during operation Contact with the heater can be avoided.
Instead of the procedure (2), the sheet 1 may be retracted from between the molds 10 and 20 and moved to the position of a heater (not shown) installed outside the molding machine. In this case, instead of the procedure (4), the sheet 1 is moved from the outside of the molding machine to a position between the molds 10 and 20.
In (8), when the mold release speed is increased by the operation of the cylinder 16 and the mold release property between the molded body and the convex mold is inferior, the operation of the cylinder 16 is opened manually or by operating the solenoid valve, and then the concave mold. Can be lowered.
It is also possible to arrange the convex mold 10 on the upper side of the sheet 1 and the concave mold 20 on the lower side of the sheet 1. In this case, in steps (5) and (6), the convex mold 10 is lowered and the concave mold 20 is raised, and in procedure (8), the convex mold 10 is raised and the concave mold 20 is lowered.

  In step (6), the following two molding methods A and B can be selected by selecting the shape of the movable frame clamps 14 and 24 and adjusting the thrust. Any molding method can be applied, and it is desirable to select a more appropriate method in consideration of a mold design, a sheet configuration, and the like.

(Forming method A)
As shown in FIG. 1A, after the thermoforming sheet 1 is sandwiched and fixed from both sides by frame clamps 14 and 24, the downward thrust of the concave side frame clamp 24 is applied as shown in FIG. By making it smaller than the upward thrust of the convex side frame clamp 14, the thermoforming sheet 1 fixed by the movable frame clamps 14 and 24 after heating is pressed against the concave mold 20 first. That is, the horizontal surface 21a of the concave mold 20 is pressed against the center portion of the thermoforming sheet 1, and the portion 2 of the thermoforming sheet 1 to be molded is projected to the convex mold 10 side. Thereby, in the thermoforming sheet 1, a level difference is generated between the portion that is in contact with the horizontal surface 21 a of the concave mold 20 and the portion that is sandwiched and fixed by the frame-shaped clamps 14 and 24, thereby extending the wrinkles of the sheet 1. Can do. After that, as shown in FIG. 1C, the sheet 1 is sandwiched between the convex mold 10 and the concave mold 20 to be formed into a three-dimensional shape.
In FIG. 1B, the difference in height between the horizontal surface 21a of the concave mold 20 and the surface 25 on which the concave frame clamp 24 holds and fixes the sheet 1 depends on the properties of the thermoforming sheet 1 and the mold shape. Therefore, although not particularly limited, it is preferably in the range of 2 to 30 mm because sheet loosening during low-temperature molding can be effectively removed. The height difference sign is positive when the horizontal surface 21a of the concave mold 20 protrudes toward the convex mold 10 from the clamp surface 25 of the concave frame clamp 24.
According to this forming method A, when a decorative sheet having a decorative layer is used, it is easy to obtain a molded article with good decorative sharpness by directing the design surface on which the decorative layer becomes visible toward the concave mold 20. Furthermore, when using a decorative sheet having a printed pattern as a decorative layer and partially decorating the resulting molded body, it is easy to align the pattern position, and uneven thickness during molding is less likely to occur. Non-uniform deformation is also reduced.
The same applies to the concave mold 20 on the lower side and the convex mold 10 on the upper side.

(Forming method B)
As shown in FIG. 2A, after the thermoforming sheet 1 is sandwiched and fixed from both sides by the frame clamps 14 and 24, the downward thrust of the concave side frame clamp 24 is applied as shown in FIG. By making it larger than the upward thrust of the convex side frame clamp 14, the thermoforming sheet 1 fixed by the movable frame clamps 14, 24 after heating is pressed against the convex mold 10 first. That is, the top surface 11c of the convex mold 10 is pressed against the central portion of the thermoforming sheet 1, and the portion 2 of the thermoforming sheet 1 to be molded is projected to the concave mold 20 side. Thereby, in the thermoforming sheet 1, a step is generated between the portion 2 a in contact with the top surface 11 c of the convex mold 10 and the portion clamped and fixed by the frame clamps 14 and 24, thereby causing the step of the sheet 1. You can stretch your heels. After that, as shown in FIG. 2C, the sheet 1 is sandwiched between the convex mold 10 and the concave mold 20 to be formed into a three-dimensional shape.

In FIG. 2B, the height difference between the horizontal surface 11a of the convex mold 10 and the surface 15 on which the convex side frame-shaped clamp 14 clamps and fixes the sheet 1 is the property of the thermoforming sheet 1 and the mold shape. However, it is preferably within the range of -30 to 15 mm because sheet slack during low-temperature molding can be effectively removed. The sign of the height difference is positive when the horizontal surface 11a of the convex mold 10 protrudes toward the concave mold 20 from the clamp surface 15 of the convex frame clamp 14, and the horizontal plane 11a is lower than the clamp surface 15. Negative when in position. In the example shown in FIG. 2B, the horizontal surface 11a of the convex mold 10 and the clamp surface 15 of the convex side frame clamp 14 are substantially on the same plane, and the height difference is approximately 0 mm. Further, the height difference between the convex side frame-shaped clamp 14 and the surface 15 for sandwiching and fixing the sheet 1 is set to less than 0 mm, and the vacuum is sucked from the vacuum hole provided in the convex mold, thereby further improving the mold reproducibility. May be better.
According to this forming method B, the sheet 1 can be stretched between the top surface 11c of the convex mold 10 and the frame-shaped clamps 14 and 24 without contacting the inclined surface 11b of the convex mold 10 or the horizontal surface 11a. Therefore, a sheet having a larger area can be allocated to the slope portion (portion formed by the slopes 11b and 21b of the molds 10 and 20) of the molded body. Therefore, when a mold having a shape with a high development rate or a portion with a large gradient is used, a molded product with good mold reproducibility is easily obtained.
The same applies to the concave mold 20 on the lower side and the convex mold 10 on the upper side.

Next, a second embodiment of the molding method and molding apparatus of the present invention will be described.
FIG. 3 is a schematic cross-sectional view illustrating a second embodiment of the molding method of the present invention. FIG. 6 is a perspective view showing a concave mold provided with a frame-like clamp used in FIG.
In the present embodiment, as the convex mold 10 and the convex side frame clamp 14, those shown in FIG. 4 can be used as in the first embodiment. As shown in FIGS. 3 and 6, the concave side frame-shaped clamp 24 has a flange portion 27 extending to the inner peripheral edge of the frame-shaped clamp 24, and the flange portion 27 is located inside the convex side frame-shaped clamp 14. A frame clamp located inside the peripheral edge is used. In this case, the concave mold 20 </ b> A is used in which the height of the horizontal surface 21 a of the concave mold body 21 is more than the thickness of the flange portion 27 and protrudes from the edge of the box 22. As a method of adjusting the height of the concave body 21, there is a method of inserting a height adjusting plate 22b on the back side of the concave body 21, and according to this method, the plate is placed in the box 22 of the concave mold 20 of FIG. The concave mold 20A shown in FIG. 6 can be configured simply by adding 22b.

  The frame clamps 14 and 24 in the present embodiment are fitted to each other on the surfaces of the sheet fixing portions 15 and 25 for sandwiching and fixing the thermoforming sheet 1 as described in the molding apparatus of the first embodiment. It is preferable to have a combination of the convex portion 31 and the concave portion 32 (see FIGS. 8 and 9). Thereby, when the sheet | seat 1 for thermoforming is clamped and fixed between both frame-shaped clamps 14 and 24, the convex part 31 protrudingly provided by one frame-shaped clamp is recessed part 32 recessedly provided by the other frame-shaped clamp. The thermoforming sheet 1 can be fixed more strongly. As a method of combining the convex portion 31 and the concave portion 32, the convex portion 31 may be provided with the convex portion 31 and the concave portion side frame clamp 24 may be provided with the concave portion 32, or the convex side frame clamp 14 may be provided with the concave portion 32. The convex part 31 may be provided on the concave side frame clamp 24, or these may be used in combination.

In this embodiment, the sheet 1 can be formed by the same method as the above-described forming method B (the convex mold is first pressed against the sheet). That is, as shown in FIG. 3 (a), the thermoforming sheet 1 is clamped and fixed from both sides by frame clamps 14 and 24, and then the concave side frame clamp 24 is clamped as shown in FIG. 3 (b). By making the pressure larger than the clamping pressure of the convex side frame-shaped clamp 14, the thermoforming sheet 1 fixed by the movable frame-shaped clamps 14 and 24 after heating is pressed against the convex mold 10 first. That is, the top surface 11c of the convex mold 10 is pressed against the center of the thermoforming sheet 1, and the portion 2 of the thermoforming sheet 1 to be molded is protruded toward the concave mold 20A. As a result, in the thermoforming sheet 1, a level difference is generated between the portion 2a in contact with the top surface 11c of the convex mold 10 and the portion clamped and fixed by the frame-shaped clamps 14 and 24, thereby extending the wrinkles. be able to. Thereafter, as shown in FIG. 3 (c), the sheet 1 is sandwiched between the convex mold 10 and the concave mold 20A and formed into a three-dimensional shape. Further, in the stage of FIG. 3B, when the thermoforming sheet 1 fixed by the movable frame clamps 14 and 24 after heating is pressed against the convex mold 10 first, the concave side frame clamp 24 The thermoforming sheet 1 is sandwiched and fixed (clamped) between the flange portion 27 of the inner peripheral edge portion and the outer peripheral edge portion 17 (here, the edge of the box 12) of the convex mold 10, and further, the skirt of the convex mold 10 The heat plasticized portion of the thermoforming sheet 1 is vacuum-sucked from the convex mold 10 through a vacuum hole 18 (see FIG. 3 (b)) provided in the (joint portion between the horizontal surface 11a and the slope 11b).
According to this configuration, a convex-side vacuum can be used effectively, and a molded product with better mold reproducibility can be easily obtained. At the time of vacuum suction, the distance between the convex part of the convex mold 10 and the flange part 27 (horizontal direction in FIG. 3B) can suppress the generation of wrinkles and further improve the mold reproducibility. 5-50 mm is preferable. Further, as the shape of the flange portion 27, the interval between the convex portion of the convex mold 10 and the flange portion 27 does not need to be uniform, and the interval between the portions having a high development rate is intentionally increased or a bridging failure occurs. The design retention and mold reproducibility can be further improved by intentionally shortening the interval between the easy-to-do portions.

When a decorative sheet having design properties is used, the molding property is less likely to change as the molding is performed at a lower temperature, and a molded article having excellent decorative sharpness is easily obtained. According to the present invention, the mold reproducibility is good even at a relatively low temperature. Therefore, the thermoforming temperature is preferably lower by 10 ° C. or more than the vacuum forming temperature of the sheet (the optimum temperature when forming the sheet by vacuum forming). Specifically, when the sheet having design properties is a thermoforming sheet having at least a thermoplastic resin layer (A) and a decorative layer (B), the glass transition temperature (Tg) of the thermoplastic resin layer (A). When (A)) is molded within a temperature range in which (Tg (A) -30) ° C. is the lower limit and (Tg (A) +10) ° C. is the upper limit, the design is not affected. In the case of a sheet, a highly glossy molded product can be obtained, and in the case of a printed decorative sheet using a pigment, a molded product free from uneven color and discoloration can be obtained. Furthermore, it is preferable because it is easy to match the pattern in the case of a decorative sheet having a printed pattern for the purpose of partial decoration of the molded body as a decorative layer.
However, the glass transition temperature (hereinafter referred to as Tg) referred to here is a film-like or viscoelasticity measurement (hereinafter referred to as DMA) measured according to JIS K7244-1 method. For the sheet-like sample piece, the temperature at which the mechanical attenuation (hereinafter referred to as tan δ) measured under the measurement conditions of a frequency of 1 Hz, a measurement start temperature of 0 ° C., and a temperature increase rate of 3 ° C./min shows a maximum value ( Called peak temperature).

  When the thermoforming sheet has a plurality of thermoplastic resin layers (A), the highest temperature among Tg of the plurality of thermoplastic resin layers (A) is defined as Tg (A). Further, at least one of the plural thermoplastic resin film layers (A) is required to have a resin layer having Tg. Therefore, when there is a layer in which tan δ does not show the maximum value among the plural thermoplastic resin layers (A) (crystalline resin such as PP), the Tg of the layer having Tg is used as the reference of the above temperature range. Further, the thermoforming temperature is more preferably (Tg (A) -25) ° C. as the lower limit and (Tg (A) +5) ° C. as the upper limit.

  More specifically, when a far infrared heater is used, the heater temperature is 200 to 500 ° C., the indirect heating time is 5 to 30 seconds, and the temperature at which the sheet can be molded by match molding, for example, the storage elastic modulus of DMA. It is preferable to set the temperature at which (E ′) is 10 to 500 MPa.

  In general, the molding temperature of the thermoplastic resin sheet depends on the viscoelasticity of the thermoplastic resin and the shape of the molded body. However, in the case of the vacuum molding method, the temperature at which the storage elastic modulus (E ′) of DMA is 50 MPa or less, pressure molding In the case of the method, a temperature at which the storage elastic modulus (E ′) of DMA is 250 MPa or less is a standard, and molding is difficult below that temperature. Specifically, in order to make the storage elastic modulus 50 MPa or less, it is necessary to heat the thermoforming sheet to Tg plus 20 ° C. or higher of the thermoplastic resin layer.

  On the other hand, the thermoforming sheet molding method of the present invention can be molded at a temperature at which the storage elastic modulus is 500 MPa or less. Specifically, the thermoforming sheet is formed from the thermoplastic resin layer (A). Molding is possible by heating to (Tg (A) -30) ° C. or higher with respect to (Tg (A)).

In general, when a thermoplastic resin sheet is heated, it often goes through the steps of primary expansion, thermal contraction, and secondary expansion (drawdown). In general-purpose thermoforming methods such as vacuum forming, the mold is shaped in the temperature range from thermal shrinkage to secondary expansion, but the molding method of the present invention is to shape in the temperature range from primary expansion to heat shrinkage. Is a feature and enables molding at a low temperature that does not affect the design.
That is, the bag that is one of the problems of the present invention is different from the bag that is solved and solved in Patent Documents 1 and 2. That is, the generation of wrinkles at the time of forming solved in Patent Document 1 and Patent Document 2 is caused by sheet slack due to secondary expansion, but wrinkles solved in the present invention are sheet slack due to primary expansion. This is due to the fact that a sheet that is difficult to stretch due to a relatively low temperature is drawn into the mold and cannot be solved by a known method such as the above method.

  The mold temperature is not particularly limited because it depends on the properties of the thermoforming sheet 1, and may be appropriately adjusted depending on the appearance, mold reproducibility, molding shrinkage, and deformation of the resulting molded body. For example, in the case of a laminated sheet having a thermoplastic resin layer having a Tg of 0 ° C. or higher, the mold temperature on the side in contact with the layer is in the range of (Tg-50) ° C. to (Tg-10) ° C. Therefore, it is preferable because mold reproducibility is improved, and a temperature gradient may be provided between the other mold as necessary. Moreover, it is preferable to cool the obtained molded object with air etc. after completion | finish of press molding. Specifically, in the range of 20 to 200 ° C., if the time for sandwiching the sheet between the convex mold and the concave mold (corresponding to the above step (7)) is 10 seconds to 5 minutes, it can be molded satisfactorily. it can.

When a laminated sheet having a decorative layer is used, there is no particular limitation as to which surface is brought into contact with the mold, but the thermoplastic resin layer (A) (the side of the design surface where the decorative layer (B) is visible) If it is made to contact with a metal mold | die, since the state in which the orientation of the metal thin-film strip of the decoration layer was aligned is easy to maintain with a metal mold | die, it is easy to obtain the molded object with favorable decoration sharpness. In addition, there are a plurality of thermoplastic resin layers (A) described later, a transparent or translucent thermoplastic resin layer (A-1), a decorative layer (B), and a thermoplastic resin layer (A -2) is a laminated sheet laminated in this order, the deformation of the decorative layer (B) becomes mild when deformed from the side of the thermoplastic resin layer (A-2) serving as the support substrate, and the design It is considered that the effect of maintaining the sex is high. On the other hand, from the viewpoint of mold reproducibility, it may be better to deform from the side of the thermoplastic resin layer having Tg (AM), that is, the one that is difficult to deform.
Therefore, it is desirable to select a more appropriate method in consideration of the mold design and the sheet configuration.

(Thermoforming sheet)
In the present invention, the thermoforming sheet may be a single layer sheet made of a resin or the like, or a laminated sheet formed by laminating a plurality of layers, but it is a decorative sheet having design properties. The effect of the present invention can be exhibited most preferably. Although there is no limitation in particular in the coloring agent which comprises the decoration layer which provides designability, when the shaping | molding method of this invention is used, a coloring agent weak to a heat | fever can also be used. Examples of heat-sensitive colorants include metal vapor deposition films, metal inks using metal flakes and metal particles, inorganic pigments such as iron oxide, azo-based organic pigments, and oil-soluble dyes.

(Decoration layer)
Specifically, the decorative layer (B) is obtained by spreading ink or paint on the thermoplastic resin layer (A) by a conventional method. In the case of a metallic design, the metal thin film may be formed by a vacuum deposition method, a sputtering method, a plating method, or the like. Moreover, there are a plurality of thermoplastic resin layers (A), which will be described later, a transparent or translucent thermoplastic resin layer (A-1), a decorative layer (B), and a thermoplastic resin layer (A- In the case of using a laminated sheet in which 2) and 2 are laminated in this order, a method of spreading on a transparent or translucent thermoplastic resin layer (A-1) is preferable from the viewpoint of design.
Examples of methods for spreading ink or paint on the thermoplastic resin film layer include gravure printing, flexographic printing, screen printing, and other printing methods, gravure coaters, gravure reverse coaters, flexo coaters, blanket coaters, roll coaters, knife coaters. Coating methods such as air knife coater, kiss touch coater, kiss touch reverse coater, comma coater, comma reverse coater, and micro gravure coater can be used.

  If the decorative layer is too thin, the concealability may be inferior and the design may be impaired. If the decorative layer is too thick, color unevenness is likely to occur during thermoforming. Therefore, when ink or paint is used as the decorative layer, the thickness of the layer is 0. 0.1 to 5 μm is preferable, more preferably 0.5 to 3 μm. When a metal thin film is used, 0.01 to 0.1 μm is preferable, and 0.02 to 0.08 μm is more preferable. Further, for the purpose of controlling the adhesion between the thermoplastic resin film layer and the decorative layer, the surface of the thermoplastic resin film may be subjected to a surface treatment such as corona treatment or primer coating.

(High gloss ink)
As a decorative layer for imparting a metallic design, a metal thin film layer formed by vacuum vapor deposition or the like can be used. In that case, the components of the metal thin film include aluminum (Al), gold (Au), platinum (Pt), silver (Ag), copper (Cu), brass (Cu—Zn), titanium (Ti), chromium (Cr ), Nickel (Ni), indium (In), molybdenum (Mo), tungsten (W), palladium (Pd), iridium (Ir), silicon (Si), tantalum (Ta), nickel chromium (Ni-Cr), Examples of the metal include stainless steel (SUS), chromium copper (Cr—Cu), and aluminum silicon (Al—Si).
If the molding method and molding apparatus of the present invention are used, it is possible to remarkably suppress the reduction in luminance due to cracks in the metal thin film layer in the high extension portion, but the above-described reduction in luminance is further suppressed by using a high-brightness ink layer made of high-brightness ink. It is preferable because it is possible. Here, the high gloss ink is an ink having a mirror-like metallic luster that is obtained by dispersing metal thin film strips in a binder resin. The content of the metal thin film strip with respect to the nonvolatile content in the ink is preferably in the range of 3 to 60% by mass. High-gloss inks using metal thin film strips are aligned with the metal thin film strips in a direction parallel to the surface of the object when the ink is printed or applied. An unobtainable high-brightness mirror-like metallic luster is obtained.

(Metal thin film strips in high brightness ink)
As the metal of the metal thin film strip used for the high-brightness ink, various metals exemplified above as the components of the metal thin film can be preferably used. As a method for forming the metal into a thin film, vapor deposition is performed in the case of a metal having a low melting point such as aluminum, and foil is formed in the case of a malleable metal such as aluminum, gold, silver, or copper, and the melting point is high and the malleability is poor. In the case of a metal, sputtering etc. can be mentioned. Especially, the metal thin film strip obtained from the vapor deposition metal thin film is used preferably. The thickness of the metal thin film is preferably 0.01 to 0.1 μm, more preferably 0.02 to 0.08 μm. The size in the surface direction of the thin metal thin film dispersed in the ink is preferably 5 to 25 μm, more preferably 10 to 15 μm. If the size of the metal thin strip is less than 5 μm, the brightness of the coating film of high-brightness ink will decrease, and clogging of the plate will occur when the ink is printed or applied by gravure or screen printing. Cause.

  Hereinafter, a method for producing a metal thin film strip will be described by way of an example in which a particularly preferable vapor deposition method is used. A polyolefin film, a polyester film, etc. can be used for the support body film which vapor-deposits a metal. First, a release layer is provided on the support film by coating or the like, and then a metal is deposited on the release layer to have a predetermined thickness. A top coat layer is applied to the surface of the deposited film to prevent oxidation. As the coating agent for forming the release layer and the topcoat layer, the same one can be used, or different ones can be used.

  Resin used for the said peeling layer or the said topcoat layer is not specifically limited. Specific examples include cellulose derivatives such as nitrocellulose, acrylic resins, vinyl resins, polyamides, polyesters, ethylene-vinyl alcohol (EVA) resins, chlorinated polyethylene, chlorinated EVA resins, petroleum resins, and the like. Can do. Solvents used for the release layer or topcoat layer include aromatic hydrocarbons such as toluene and xylene; aliphatic or alicyclic hydrocarbons such as n-hexane and cyclohexane; esters such as ethyl acetate and propyl acetate; Alcohols such as methanol, ethanol and isopropyl alcohol; ketones such as acetone and methyl ethyl ketone; alkylene glycol monoalkyl ethers such as ethylene glycol monoethyl ether and propylene glycol monomethyl ether are preferably used.

  The metal vapor deposition film is immersed in a solvent that dissolves the release layer and the top coat layer and stirred to separate the metal vapor deposition film. Further, the peeled metal vapor-deposited film is stirred in a solvent to form a metal thin film strip having a size in the plane direction of about 5 to 25 μm, filtered and dried. The solvent used for peeling is not particularly limited as long as it dissolves the peeling layer and the topcoat layer. Also when a metal thin film is produced by sputtering, it can be made into a metal thin film strip by the same method as described above. When using a metal foil, it may be immersed in a solvent and pulverized to a predetermined size with a stirrer.

  The metal thin film strip is preferably surface-treated in order to enhance dispersibility in the ink. Examples of the surface treatment agent include organic fatty acids such as stearic acid, oleic acid, and palmitic acid; isocyanates such as methylsilyl isocyanate; and cellulose derivatives such as nitrocellulose, cellulose acetate propionate, cellulose acetate butyrate, and ethyl cellulose. It is made to adsorb | suck to the surface of a metal thin film strip by a well-known and usual method.

(Binder resin in high brightness ink)
As the binder resin used for the high gloss ink, those conventionally used in conventional gravure ink, flexo ink, screen ink, paint, and the like can be used. Specific examples include acrylic resins for paints, vinyl chloride resins, vinylidene chloride resins, vinyl chloride-vinyl acetate resins, ethylene-vinyl acetate resins, polyolefin resins, chlorinated olefin resins, ethylene-acrylic resins and the like; or A polyurethane resin for coating, a polyamide resin, a urea resin, an epoxy resin, a polyester resin, a petroleum resin, a cellulose derivative resin and the like are preferably used. Further, those obtained by chemically bonding polar groups such as carboxylic acid group, phosphoric acid group, sulfonic acid group, amino group, quaternary ammonium base to these resins may be used or used in combination.

(Additive in high gloss ink)
If necessary, the high-brightness ink has no defoaming, settling prevention, pigment dispersion, fluidity modification, anti-blocking, antistatic, antioxidation, light stability in the ink as long as it does not impair the design and spreadability. Various additives used in conventional gravure inks, flexo inks, screen inks, paints, etc. may be added for the purpose of properties, ultraviolet absorption, internal crosslinking and the like. Examples of such additives include coloring pigments, dyes, waxes, plasticizers, leveling agents, surfactants, dispersants, antifoaming agents, chelating agents, polyisocyanates, and the like.

(Solvent in high brightness ink)
As the solvent used in the high gloss ink, known conventional solvents used in conventional gravure ink, flexo ink, screen ink, paint, and the like can be used. Specifically, aromatic hydrocarbons such as toluene and xylene; aliphatic or alicyclic hydrocarbons such as n-hexane and cyclohexane; esters such as ethyl acetate and propyl acetate; methanol, ethanol and isopropyl alcohol Examples include alcohols; ketones such as acetone and methyl ethyl ketone; alkylene glycol alkyl ethers such as ethylene glycol monoethyl ether and propylene glycol monomethyl ether.

(Preparation method of high brightness ink)
Generally, in order to stably disperse the ink blending raw material, the pigment and other additives are finely divided to submicron by kneading using a roll mill, ball mill, bead mill, or sand mill. However, in the above-mentioned high-brightness ink, the metal thin film strip to be blended for expressing the metallic luster is preferably 5 to 25 μm, and when the above-mentioned kneaded meat is formed, the metal thin film strip becomes fine particles. In addition, the metallic luster may be extremely lowered. Therefore, it is desirable not to perform kneading when preparing a high-brightness ink, but to simply mix the above blended raw materials to obtain an ink. For this purpose, for the purpose of improving dispersibility, it is preferable to surface-treat the metal thin film strip as described above.

In the present invention, in particular, when a laminated sheet having a configuration in which a decorative layer is sandwiched between thermoplastic resin layers is used, it can be molded into a desired shape without impairing the excellent design of the laminated sheet. This is preferable.
Specifically, a transparent or translucent thermoplastic resin layer (A-1), a decorative layer (B), and a thermoplastic resin layer (A-2) serving as a support substrate are laminated in this order. A laminated sheet is preferred.
In this laminated sheet, the transparent or translucent thermoplastic resin layer (A-1) side becomes the surface layer, and the decorative layer (B) having a high design property is visually observed through the transparent or translucent thermoplastic resin layer (A-1). It is possible. One or more decorative protective layers, ink layers, adhesive layers, and the like may be provided between the transparent or translucent thermoplastic resin layer (A-1) and the decorative layer (B). In addition, on the transparent or translucent thermoplastic resin layer (A-1), one or more surface protective layers (topcoat layers) may be provided on the side that becomes the surface layer during molding.

In addition, since the three-dimensional molded body obtained by the molding method of the present invention has excellent decorative sharpness, it is used for in-mold molding (insert molding) in which the molded body is inserted into an injection mold and integrally injection molded. It can be used suitably. In that case, since the thermoplastic resin layer (A-2) serving as the support substrate is the layer closest to the injection molding resin side of the obtained molded article, it may have heat-fusibility with the injection resin. preferable. In addition, the thermoplastic resin layer (A-2) serving as the support substrate also has the role of protecting the decorative layer and assisting the strength and rigidity of the laminated sheet or the molded article to be obtained.
One or more other ink layers, adhesive layers, and the like may be provided between the decorative layer (B) and the thermoplastic resin layer (A-2) serving as the support substrate. Moreover, when using the lamination sheet which has this structure, the temperature of the heat plasticization at the time of shaping | molding is the higher one of the said layer (A-1) and the said layer (A-2) that the said temperature of heat plasticization When the glass transition temperature is expressed as Tg (AM), it is preferably within the temperature range of (Tg (AM) -30) ° C to (Tg (AM) +10) ° C.

(Transparent or translucent thermoplastic resin layer (A-1))
The thermoplastic resin layer (A-1) that can be used for the thermoforming sheet is preferably in the form of a film, and a film having spreadability by heating is used. The thermoplastic resin film is preferably a transparent or translucent single layer or multilayer film, and may contain a colorant. In the match molding, a film mainly composed of a thermoplastic resin having a Tg in the range of 30 to 300 ° C. is preferable because a molding process by heat is performed, and a more preferable Tg is 50 to 250 ° C. Examples of the thermoplastic resin include polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, acrylic resins such as polymethyl methacrylate and polyethyl methacrylate, ionomer resins, polystyrene, polyacrylonitrile, Acrylonitrile-styrene resin, methyl methacrylate-styrene resin, polyamide resin such as nylon, ethylene-vinyl acetate resin, ethylene-acrylic acid resin, ethylene-ethyl acrylate resin, ethylene-vinyl alcohol resin, polyvinyl chloride, polyvinylidene chloride, etc. Chlorine resin, fluororesin such as polyvinyl fluoride and polyvinylidene fluoride, polycarbonate resin, cyclic polyolefin resin, modified poly Niren'eteru resins, methylpentene resins, and cellulose-based resin is preferably used. Among these thermoplastic resins, one or two or more selected from the group of acrylic resins, polyester resins, polycarbonate resins, and cyclic polyolefin resins are the main components because of their excellent thermoformability and sharpness of the decorative layer. A film is preferred.
In addition, two or more of the exemplified resins may be mixed or multilayered as long as the transparency of the film is not impaired.
Further, for the purpose of improving the impact resistance, the various resins exemplified above used as the thermoplastic resin film may be modified with rubber within a range that does not impair the transparency. There are no particular restrictions on the method of making a rubber-modified product, but a method in which a rubber component monomer such as butadiene is added and copolymerized at the time of polymerization of various resins, and the resin and synthetic rubber or thermoplastic elastomer are heat-melt blended. A method is mentioned. In addition, the thermoplastic resin film may contain various additives that are commonly used for film applications such as an antioxidant, an ultraviolet absorber, and a lubricant as long as the transparency is not impaired. Furthermore, from the viewpoint of designability, a colorant such as a pigment or a dye can be contained, and the transparency can be intentionally lowered. The method for producing the thermoplastic resin film is not particularly limited, and may be formed into a film by a conventional method. Further, the thermoplastic resin film may be stretched in a uniaxial direction or a biaxial direction within a range that does not impair the extensibility during thermoforming. good.
The thickness of the thermoplastic resin film is not particularly limited, but it is 30 to 2000 μm because the decorative protective layer (described later) and the coating layer when the decorative layer is a spreading layer such as ink and the thermoformability are good. The range is preferably 50 to 500 μm.

(Thermoplastic resin layer (A-2) serving as a support substrate)
As the thermoplastic resin layer (A-2) serving as a supporting substrate used in the thermoforming sheet, a film mainly composed of a thermoplastic resin having a Tg in the range of 30 to 300 ° C. is used for performing match mold molding. A more preferable Tg is 50 to 250 ° C. Examples of the thermoplastic resin include acrylonitrile / butadiene / styrene (ABS) resin, acrylonitrile / acrylic rubber / styrene (AAS) resin, acrylonitrile / ethylene rubber / styrene (AES) resin, (meth) acrylic ester / styrene. (MS) resin, styrene / butadiene / styrene (SBS) resin, styrene / isoprene / butadiene / styrene (SIBS) resin, polyethylene (PE) resin, polypropylene (PP) resin, vinyl chloride (PVC) resin, etc. General-purpose resin, olefin elastomer (TPO), vinyl chloride elastomer (TPVC), styrene elastomer (SBC), urethane elastomer (TPU), polyester elastomer (TPEE), polyamide elastomer It can be a thermoplastic elastomer (TPE), etc. (TPAE) and the like. Further, two or more kinds of the exemplified resins may be mixed or multilayered. Among these, since the forming property is excellent even in a molded body having a complicated shape typified by automobile exterior parts, polypropylene resins, polyethylene resins, blends thereof, AAS resins, ABS resins, etc. More preferably used. These resins may contain rubber modifiers such as ethylene propylene rubber (EPR), SBS, SIBS, styrene / ethylene / butadiene / styrene (SEBS) for the purpose of improving impact strength and the like. . Although the thickness of the thermoplastic resin layer (A-2) used as a support base material is not specifically limited, For example, 10 micrometers-3000 micrometers is preferable.

(Inorganic filler in the thermoplastic resin layer (A-2) serving as a support substrate)
The laminated sheet for thermoforming becomes a three-dimensional shaped body by thermoforming. At this time, when the molding shrinkage of the thermoplastic resin layer (A-2) and the thermoplastic resin film layer (A-1) used as the supporting base material are different, the molded body is deformed and good. It is difficult to keep a simple shape. In this case, when an inorganic filler is added to the resin of the thermoplastic resin layer (A-2) serving as the support base material, the molding shrinkage can be finely controlled, and the support base resin layer and the thermoplastic resin film layer Since the difference in the molding shrinkage rate of the thermoplastic resin can be reduced, deformation during and after molding can be prevented. The kind of inorganic filler that can be used in the present invention is not particularly limited, and examples thereof include talc, calcium carbonate, clay, diatomaceous earth, mica, magnesium silicate, and silica.

  The amount of the inorganic filler added to the thermoplastic resin layer (A-2) serving as the support substrate is set to a mass percentage of the resin of the layer (A-2) from the viewpoint of the balance between moldability and molding shrinkage. 5-60 mass% is preferable. The particle size of the inorganic filler is not particularly limited, but if the particle size is too large, the surface of the layer (A-2) is uneven, and in the case of a decorative sheet having a decorative layer, the decorative sharpness may be impaired. . For this reason, since the layer (A-2) which is the base of the decoration layer is required to have smoothness, the average particle size of the inorganic filler added to the layer (A-2) is preferably 8 μm or less, and more preferably 4 μm or less. preferable. In particular, in the case of a decorative sheet having a mirror-like metallic luster, 2 μm or less is preferable.

(Colorant in the thermoplastic resin layer (A-2) to be the support substrate)
It is preferable to add a colorant to the thermoplastic resin layer (A-2) serving as the support base material because the concealability of the base color of the molded article is improved. The colorant used here is not particularly limited, and customary inorganic pigments, organic pigments, dyes and the like used for coloring general thermoplastic resins can be used in accordance with the intended design. For example, inorganic pigments such as titanium oxide, titanium yellow, iron oxide, complex oxide pigments, ultramarine, cobalt blue, chromium oxide, bismuth vanadate, carbon black, zinc oxide, calcium carbonate, barium sulfate, silica, talc; azo Pigments, phthalocyanine pigments, quinacridone pigments, dioxazine pigments, anthraquinone pigments, isoindolinone pigments, isoindoline pigments, perylene pigments, perinone pigments, quinophthalone pigments, thioindigo pigments, diketopyrrolo Organic pigments such as pyrrole pigments; metal complex pigments and the like. Moreover, as a dye, it is preferable to use 1 type, or 2 or more types mainly selected from the group of oil-soluble dyes.

  The amount of the colorant added to the thermoplastic resin layer (A-2) serving as the support base varies depending on the type of the colorant, the thickness and color tone of the target thermoforming sheet, and the hue and background color. In order to ensure the concealment property and maintain the impact strength, the mass percentage with respect to the resin constituting the layer (A-2) is preferably in the range of 0.1 to 20% by mass, more preferably 0. It is in the range of 5 to 15% by mass. When the addition amount of the colorant exceeds 20% by mass with respect to the resin, the impact strength decreases, and when the addition amount of the colorant is less than 0.1% by mass, the hue and the background color are not sufficiently concealed. There is a tendency.

(Other additives in the thermoplastic resin layer (A-2) to be the support substrate)
Further, the thermoplastic resin layer (A-2) serving as a supporting substrate has a plasticizer, an antioxidant, an ultraviolet absorber, an antistatic agent, a flame retardant, and a lubricant as long as its impact strength and moldability are not impaired. Such additives may be added, and these additives may be used alone or in combination of two or more.

(Decorative protective layer)
Between the thermoplastic resin film layer (A-1) and the decorative layer (B), one or more decorative protective layers are provided for the purpose of improving heat resistance, solvent resistance, design properties, weather resistance, and the like. Also good. In particular, when the decorative layer (B) is made of high-brightness ink, it is desirable to provide the following decorative protective layer as the ink protective layer. The type of resin that can be used in the decorative protective layer is not particularly limited as long as it does not impair the spreadability of the thermoforming sheet, but the ease of adjusting the crosslink density, weather resistance, and the thermoplastic resin film layer (A-1 Acrylic resin is preferable from the viewpoint of adhesiveness to the above. The crosslinking mechanism of the resin is not particularly limited, and in the case of an acrylic resin, UV curing, EB curing, hydroxyl group-containing copolymer / isocyanate curing, silanol / water curing, epoxy / amine curing, and the like can be used. Of these, hydroxyl group-containing copolymer / isocyanate curing is preferred from the viewpoints of easy adjustment of the crosslinking density, weather resistance, reaction rate, presence or absence of reaction byproducts, production cost, and the like.

  Further, in order to impart designability to the decorative protective layer, a coloring agent may be added to the decorative protective layer to form a colored layer. In this case, the amount of colorant added varies depending on the type of colorant, the target color tone, the thickness of the decorative protective layer, etc., but the total light transmittance of the decorative protective layer is not concealed by the decorative layer (B). It is preferably 20% or more, and more preferably the total light transmittance is 40% or more. As the colorant that can be added to the decorative protective layer, a pigment is preferable. The pigment used here is not particularly limited, and known and commonly used pigments such as colored pigments, metallic pigments, interference color pigments, fluorescent pigments, extender pigments, and antirust pigments can be used.

  Examples of the coloring pigment include quinacridone pigments such as quinacridone red, azo pigments such as pigment red, organic pigments such as phthalocyanine pigments such as phthalocyanine blue, phthalocyanine green, and perylene red; inorganic pigments such as titanium oxide and carbon black. Is mentioned. Examples of metallic pigments include aluminum powder, nickel powder, copper powder, brass powder, and chromium powder. Examples of the interference color pigment include pearl luster-like pearl mica powder and pearl luster-like colored pearl mica powder.

  As fluorescent pigments, quinacridone pigments, anthraquinone pigments, perylene pigments, perinone pigments, diketopyrrolopyrrole pigments, isoindolinone pigments, condensed azo pigments, benzimidazolone pigments, monoazo pigments, Insoluble azo pigments, naphthol pigments, flavanthrone pigments, anthrapyrimidine pigments, quinophthalone pigments, pyranthrone pigments, pyrazolone pigments, thioindigo pigments, anthanthrone pigments, dioxazine pigments, phthalocyanine pigments, indones Organic pigments such as Ron-based pigments; metal complexes such as nickel dioxin yellow and copper azomethine yellow; metal oxides such as titanium oxide, iron oxide and zinc oxide, metal salts such as barium sulfate and calcium carbonate, carbon black, aluminum and mica Inorganic pigments such as It is.

(Lamination of laminated sheets)
In order to join the decorative layer (B) or other ink layer and the thermoplastic resin layer (A-2) serving as a supporting substrate, it is preferable to bond them through an adhesive layer or a pressure-sensitive adhesive layer.
As a bonding method using an adhesive layer, lamination can be performed by a dry lamination method, a wet lamination method, a hot melt lamination method, or the like using a conventional solvent-type adhesive. The adhesive constituting the adhesive layer is a conventional phenol resin adhesive, resorcinol resin adhesive, phenol-resorcinol resin adhesive, epoxy resin adhesive, urea resin adhesive, polyurethane adhesive, Thermosetting resin adhesives such as polyaromatic adhesives; reactive adhesives using ethylene-unsaturated carboxylic acid copolymers; vinyl acetate resins, acrylic resins, ethylene vinyl acetate resins, polyvinyl alcohol, polyvinyls Thermoplastic resin adhesives such as acetal, vinyl chloride resin, nylon, cyanoacrylate resin; rubber adhesives such as chloroprene adhesive, nitrile rubber adhesive, SBR adhesive, natural rubber adhesive, etc. It is done. In particular, an acrylic urethane adhesive is preferable because the adhesiveness between the acrylic resin and the polypropylene resin is good and the followability of elongation at the time of vacuum molding and match molding is good.

The adhesive coating methods are gravure coater, gravure reverse coater, flexo coater, blanket coater, roll coater, knife coater, air knife coater, kiss touch coater, kiss touch reverse coater, comma coater, comma reverse coater, micro reverse coater, etc. The coating method can be used. The coating amount of the adhesive, the adhesive is sufficient, for drying is good is preferably in the range of 0.1 to 30 g / ^{m 2,} particularly preferably from 2 to 10 g / ^{m 2.} If the applied amount of the adhesive is too small, the adhesive strength is weakened, and if the applied amount of the adhesive is too large, the drying property tends to decrease. The thickness of the adhesive layer is preferably in the range of 0.1 to 30 μm, more preferably 1 to 20 μm, and particularly preferably 2 to 10 μm.

  Plasma treatment, corona treatment, flame treatment, electron beam irradiation is performed on the adhesive surface of the thermoplastic resin layer (A-2) serving as a support substrate for the purpose of improving the affinity with the adhesive constituting the adhesive layer. Surface treatment such as treatment, roughening treatment, ozone treatment, etc .; dry plating treatment such as vacuum deposition, sputtering, ion plating, etc. may be applied.

  Moreover, it can replace with an adhesive bond layer and can also provide an adhesive layer. As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, acrylic pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, polyalkyl silicon-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, polyester-based pressure-sensitive adhesives, and the like are preferably used.

(Surface protective layer)
In the sheet for thermoforming used in the present invention, performance such as designability, abrasion resistance, scratch resistance, weather resistance, stain resistance, water resistance, chemical resistance, and heat resistance is provided on the surface side during molding. In order to impart, one or more transparent, translucent or colored clear topcoat layers can be provided as the surface protective layer. As the topcoat agent, a lacquer type, a crosslinking type with isocyanate or epoxy, a UV crosslinking type, or an EB crosslinking type is preferably used as long as the spreadability of the thermoforming sheet is not hindered.

  EXAMPLES Hereinafter, although this invention is demonstrated with a specific example, this invention is not limited to the Example shown below. In addition, the physical property evaluation in each Example and Comparative Example was performed by the following measurement method or test method. Unless otherwise specified, both “parts” and “%” are based on mass.

Example 1
A method for producing a laminated sheet and a match mold forming method are shown below.
(A-1) Thermoplastic resin film layer As a transparent or translucent thermoplastic resin film layer (A-1), a rubber-modified PMMA film (trade name “Technoloy S-001” having a haze of 0.1% and a thickness of 125 μm is used. ”, Manufactured by Sumitomo Chemical Co., Ltd., Tg = 125 ° C.).

(A-1 / B intermediate layer) decorative protective layer In order to improve the adhesion between the thermoplastic resin film layer (A-1) and the decorative layer (B), an acrylic polyol resin “6KW-032E” (trade name, large To a mixed solution of 46 parts by solid content 38% (solvent: ethyl acetate), hydroxyl value 30 KOHmg / g) and 46 parts of 4-methyl-2-pentanone manufactured by Nippon Ink Chemical Industry Co., Ltd., isocyanurate ring-containing polyisocyanate “BURNOCK” DN-981 "(trade name, manufactured by Dainippon Ink & Chemicals, Inc., solid content 75% (solvent: ethyl acetate), functional group number 3, NCO concentration 14%) 8 parts were mixed (100 parts in total) to protect the decoration A layer solution (primer) was prepared.

(B) Decoration layer 10 parts of aluminum thin film strip (thickness 0.04 μm, size in the surface direction 5 to 25 μm), 37.25 parts of ethyl acetate, 30 parts of methyl ethyl ketone, 31.5 parts of isopropyl alcohol, nitrocellulose 1 25 parts were mixed (a total of 110 parts) to prepare an aluminum thin film strip slurry.
30 parts of the obtained aluminum thin-film strip slurry, 3 parts of carboxylic acid-containing vinyl chloride-vinyl acetate resin ("Vinylite VMCH" manufactured by UCC) as a binder resin, urethane resin ("Polyurethane 2593" manufactured by Arakawa Chemical) non-volatile content 32%) is mixed with 8 parts of ethyl acetate, 23 parts of ethyl acetate, 26 parts of 4-methyl-2-pentanone, and 10 parts of isopropyl alcohol (total 100 parts), and the decoration of the aluminum thin film strip concentration in the nonvolatile content is 35% by mass A layer solution (high gloss ink) was prepared.

(B / A-2 intermediate layer) Adhesive As the main agent for adhering the thermoplastic resin film layer (A-1) having the decorative layer (B) and the thermoplastic resin layer (A-2) serving as the supporting substrate. , 15 parts of aromatic polyester polyol resin “LX-703VL” (trade name, manufactured by Dainippon Ink & Chemicals, Inc.) As a curing agent, aliphatic polyisocyanate “KR-90” (trade name, manufactured by Dainippon Ink & Chemicals, Inc.) ) 1 part of ethyl acetate as a diluent and 18 parts of ethyl acetate were mixed (a total of 34 parts) to prepare a polyester urethane adhesive.

(A-2) Thermoplastic resin layer serving as a supporting substrate As the thermoplastic resin layer (A-2) serving as a supporting substrate, propylene-ethylene random copolymer “FS3611” (trade name, manufactured by Sumitomo Chemical Co., Ltd.) is used. Two types in which the first layer (C-1) containing the main component and the second layer (C-2) containing the propylene-butene random copolymer “SP7834” (trade name, manufactured by Sumitomo Chemical Co., Ltd.) as the main component are laminated. A two-layer sheet was used.
For the first layer (C-1), 80 parts of “FS3611”, 10 parts of low density polyethylene “F200” (trade name, manufactured by Sumitomo Chemical Co., Ltd.), ethylene propylene rubber “P-0480” (trade name, Mitsui) Chemical) 10 parts, black masterbatch "Peony Black F31246" (trade name, manufactured by Dainippon Ink & Chemicals, low density polyethylene / carbon black = 60/40) 2 parts dry blended with a drum tumbler (total 102 parts) Thus, a resin for the layer (C-1) was produced.
For the second layer (C-2), 35 parts of “SP7834”, 10 parts of “F200”, 15 parts of “P-0480”, talc masterbatch (talc with an average particle size of 1.8 μm / “SP7834”) ”= 60/40) For 100 parts in total of 40 parts, 2 parts of“ Peony Black F31246 ”were dry blended using a drum tumbler (a total of 102 parts) to obtain a resin for the layer (C-2). Produced. Talc contained in the layer (C-2) was 24% by mass.
Next, using two extruders, a 50 mmφ single screw extruder and a 65 mmφ single screw extruder, the raw material resins for the above two types of layers (C-1) and (C-2) are respectively 210 ° C. Melt and laminate two layers so that the layer composition ratio of layer (C-1) / layer (C-2) = 30/70 with a feed block made by Clawren, and extrusion into a sheet through a T-die Then, it was immediately cooled with a metal roll whose temperature was adjusted to 40 ° C. to obtain a sheet for a supporting base resin layer having a thickness of 0.30 mm.
The laminate (A-2) composed of the layer (C-1) and the layer (C-2) did not show a maximum value when tan δ was 0 ° C. or higher in the DMA measurement.

(Sheet stacking method)
The rubber-modified PMMA film (A-1) was coated and dried with a solution for the decorative protective layer (A-1 / B intermediate layer) using a microgravure coater to a dry film thickness of 2.0 μm, and then 50 Aging treatment was carried out at 3 ° C. for 3 days. Next, the high-gloss ink as the decorative layer (B) was applied and dried on the decorative protective layer using a gravure coater to a dry film thickness of 2.0 μm. Further, the corona so that the wetting index is 40 dyne / cm on the adhesive surface (layer (C-1) containing propylene-ethylene random copolymer as a main component) of the sheet for the thermoplastic resin layer (A-2) to be the supporting substrate. After the treatment, the adhesive (B / A-2 intermediate layer) was applied and dried to a dry film thickness of 5 μm using a micro gravure coater, and the high-brilliance ink coated surface of the rubber-modified PMMA film was And aged for 3 days at 50 ° C. to obtain a laminated sheet for molding (S-1). The 20 ° gloss value (measurement angle: 20 degrees) of the sheet (S-1) was 1050%.

(Measurement method of 20 ° gloss value)
Here, the 20 ° gloss value was measured according to JIS Z8741 using “Micro-TRI-gloss” manufactured by BYK Gardner (the same applies to each of the following examples and comparative examples).

(Match mold molding method)
(Evaluation mold)
The horizontal surface 11a and the box 12 are a rectangle (area 373 cm ² ) with a circumference of 183 × 204 mm (the outer periphery of the inclined surface 11b of the convex portion is 113 × 158 mm), the top surface 11c is a rectangle with 51 × 66 mm, and the horizontal surface 11a to the top surface 11c The height is 50 mm, the slope of the slope 11b is 35, 55, 60, 70 °, the joint between the top surface 11c and the slope 11b is 0.5, 1, 5, 3 mmR, and the joint between the slopes 11b is 5 mmR. A trapezoidal convex mold 10 having a joint of the slope 11b and the horizontal surface 11a of 0.5 mmR was used. Also, two types of concave molds were designed so that the clearance when the concave mold and the convex mold were combined was 400 μm and 200 μm, and the former was used for the moldability evaluation of this example. Further, a vacuum hole having a diameter of 0.5 mm was provided at the joint between the convex horizontal surface 11a and the slope 11b, and an air vent hole having a diameter of 0.5 mm was provided at the joint between the concave bottom surface 21c and the slope 21b.
Also, as the frame clamps 14 and 24, a frame clamp having an inner edge of a rectangle of 190 × 210 mm and a width of 10 mm and having no flange portion is used, and the fitting between the concave frame clamp and the convex frame clamp is performed. The part was made into the shape shown to 32 and 31 of FIG. The area of the clamp part was 84 cm ² .
In addition, as a steel material for the mold and frame clamp, a hard aluminum alloy “Alumino HARD” (trade name) manufactured by Daido Amister is used, and a vertical machining center “NV5000” (trade name) manufactured by Mori Seiki is used. Produced.
In addition, as a method of operating the frame clamp, four sets of movable cylinders 16 and 26 are used. Specifically, the air cylinder “Jig Cylinder C Series CDA50 × 50” (trade name, cylinder diameter 50 mm, Stroke 50 mm, rods (16a and 17a) diameter 20 mm) were used.
The mass of the entire concave mold including the movable frame clamp and the air cylinder and the total mass of the convex mold were both about 25 kg (both weighed about 25 kgf).

(Molding condition)
For the match molding of this example, a small vacuum forming machine of FE38PH manufactured by Hermis was used. Attach the concave and concave movable frame clamps to the plug movable device (upper side), and the convex and convex movable frame clamps to the mold movable device (lower side). Carried out.
(1) The laminate sheet (S-1) is fixed with a clamp of a molding machine so that the thermoplastic resin film layer (A-1) side is on the upper side.
(2) The upper heater (not shown) is moved above the sheet (S-1) (the lower heater is not used).
(3) The sheet (S-1) is heated to a predetermined temperature.
(4) Retract the heater.
(5) The concave mold 20 fixed to the fixed plate 23 is lowered, and the convex mold 10 fixed to the fixed plate 13 is raised.
(6) Using the lowering of the concave mold 20 and the raising of the convex mold 10, the sheet 1 is sandwiched between the movable frame clamps 14 and 24 of the mold, and then the sheet is sandwiched between the concave mold 20 and the convex mold 10 as they are. To obtain a three-dimensional shape.
(7) Hold the sheet between the concave mold 20 and the convex mold 10 for 1 minute.
(8) After raising the concave mold 20 and lowering the convex mold 10, the molded body having a three-dimensional shape is cooled with air for 5 seconds.
(9) Open the molding machine clamp.
A match mold molded body was obtained by the steps (1) to (9).

Specifically, the heater temperature was 370 ° C., the distance between the sheet and the heater was 130 mm, the heating time was 12 seconds, and the sheet temperature at the start of molding was 115 ° C. In addition, sheet temperature uses the infrared radiation thermometer IT2-80 (emissivity (epsilon) = 0.95) by Keyence Corporation, and the sheet | seat temperature near the upper part of a metal mold | die lower side (heat used as a support base material). It measured from the plastic resin layer (A-2) side. The maximum temperature when the sheet was heated with a heater was taken as the molding temperature.
Also, using a mold temperature controller, the concave mold temperature was 95 ° C. and the convex mold temperature was 75 ° C. Furthermore, as the concave movable frame clamp, a frame clamp (FIG. 5) having no flange portion is used, and the lowering pressures of the four air cylinders (50 mmφ) for moving the frame clamp are all 1 kgf / cm. ² {about 0.1 MPa} (thrust: about 80 kgf {about 800 N}), the rising pressures of four convex air cylinders (50 mmφ) are all 2 kgf / cm ² {about 0.2 MPa} (thrust: about 160 kgf { About 1600 N}), the rising pressure of the concave movable air cylinder (104 mmφ) and the rising pressure of the convex movable air cylinder (112 mmφ) are 5 kgf / cm ² {about 0.5 MPa} (thrust: about 425 kgf {about 4250 N}) 492kgf {about 4920N}), and press the sheet fixed by the movable frame clamp after heating to the concave shape first That it was used molding A (Figure 1). The clamping force for fixing the sheet with the frame clamp is about 80 kgf {about 800 N} (the stress is about 0.95 kgf / cm ² {about 95 kPa}), and the mold closing force between the concave mold and the convex mold at the time of molding is ( Concave thrust 425 kgf + concave mold weight 25 kgf−convex frame clamp thrust 160 kgf = 290 kgf) {about 2.9 kPa} (stress is about 0.78 kgf / cm ² {about 78 kPa}).

(Method for evaluating moldability)
As a method for evaluating the moldability of a molded body obtained by the above method, the state of occurrence of wrinkles was visually evaluated.
[Evaluation Criteria] ○: No wrinkle is generated, Δ: Wrinkles of less than 3 mm are generated at the rising portion of the molded body, ×: Wrinkles of 3 mm or more are generated in the molded body, or other remarkable appearance defects are generated (specifically, , Generation of cooling marks called chilled marks, generation of compression marks, generation of vacuum hole marks, etc.)

(Method for evaluating mold reproducibility of molded products)
As a method for evaluating the mold reproducibility of the molded body obtained by the above method, R reproducibility was measured for a 3 mmR portion at the four-side corner portion of the top surface of the molded body.
[Evaluation Criteria] A: R reproducibility 80% or more, O: R reproducibility 60% or more and less than 80%, Δ: R-type reproducibility 40 or more and less than 60%, X: R reproducibility 40% or less

(Glossiness evaluation method for molded products)
The 20 ° gloss value at a development rate of 110% and a development rate of 150% was measured at the top and slope portions of the molded product, and the gloss retention was calculated from the change in gloss value before and after molding. As a method for measuring the development rate, the thickness change rate was calculated.
[Evaluation criteria] ◎: Gloss retention 80% or more, ○: Gloss retention 60% or more and less than 80%, Δ: Gloss retention 40% or more and less than 60%, X: Gloss retention 40% or less

(Evaluation results)
As a result of evaluating the molded body (M-1) by the above-described evaluation method, the evaluation of molding feasibility was ○, the mold reproducibility evaluation was ○, the 20 ° gloss value of the 110% development ratio was 850%, and the gloss retention was 81%. Yes, the gloss evaluation at a development rate of 110% was ◎. Further, the 20 ° gloss value at a development rate of 150% was 750%, the gloss retention was 71%, and the gloss evaluation at a development rate of 150% was ◯.
From the above results, it was found that the molded product (M-1) obtained in Example 1 had good mold reproducibility and metallic gloss.

Example 1a
A molded body (M-1a) was obtained in the same manner as in Example 1 except that a black grid pattern with an interval of 1 mm was previously printed on the decorative layer (B) side of the thermoplastic film layer (A-1). . When the development rate was 110%, almost no distortion of the grid pattern was observed. When the development rate was 150%, the grid pattern itself was deformed, but almost no distortion of the ruled line was observed.

(Example 2)
Using the frame-shaped clamp 24 with the flange portion 27 shown in FIG. 6 as the concave frame-shaped clamp, the descending pressures of the four air cylinders that move the frame-shaped clamp are all 0.2 MPa, and the four convex air All the rising pressures of the cylinders were set to 0.1 MPa, and the same method as in Example 1 was used except that the molding method B (FIG. 3) in which the sheet fixed by the movable frame clamp after heating was pressed against the convex mold first. Thus, a laminated sheet for molding (S-2) and a molded body (M-2) were obtained. The clamping force for fixing the sheet with a frame clamp is about 800 N (stress is about 95 kPa), and the mold closing force between the concave mold and the convex mold at the time of molding is about 2.9 kPa (stress is about 85 kPa (horizontal plane 21a is Next, as a result of evaluating the molded body (M-2), the molding propriety evaluation was ◯, the mold reproducibility evaluation was ◎, and 110% of the developed part was a rectangular shape with a circumference of 175 × 196 mm (area 343 cm ² ). The 20 ° gloss value was 800%, the gloss retention rate was 76%, and the gloss evaluation of the 110% developed portion was ○, and the 20 ° gloss value of the 150% developed portion was 650%, and the gloss retention rate was It was 62%, and the gloss evaluation of the 150% developed portion was good.

Example 2a
A molded body (M-2a) was obtained in the same manner as in Example 2 except that a black grid pattern with an interval of 1 mm was previously printed on the decorative layer (B) side of the thermoplastic film layer (A-1). . Almost no distortion of the grid pattern was observed at the development rate of 110%, but the ruled lines looked slightly distorted at the development rate of 150%.

(Example 3)
The thermoplastic resin film layer (A-1) (Tg = 125 ° C.) has a thickness of 75 μm, and the thermoplastic resin layer (A-2) serving as the support base is made of a transparent ABS resin (methyl methacrylate-acrylonitrile- A butadiene-styrene copolymer, trade name “SXH-290”, manufactured by Nippon A & L Co., Ltd., Tg = 115 ° C.), which is a single-layer sheet having a thickness of 200 μm formed using only a 65 mmφ single-screw extruder. A laminated sheet for molding (S-3) was obtained in the same manner as in Example 1 except that the adhesive coating side was changed to the high glitter ink coating surface. The 20 ° gloss value of the sheet (S-3) was 950%. Further, a molded body (M-3) was obtained in the same manner as in Example 1 except that a concave mold designed to have a clearance of 200 μm was used.
As a result of evaluation of the molded product (M-3), the evaluation of moldability was ○, the mold reproducibility evaluation was ◎, the 20 ° gloss value of the 110% developed part was 800%, and the gloss retention was 84%, 110%. The gloss evaluation of the developed part was ◎. Further, the 20 ° gloss value of the 150% developed part was 600%, the gloss retention was 63%, and the gloss evaluation of the 150% developed part was ○.

Example 4
The same as in Example 1 except that the primer and the high-brightness ink were not used, and a 0.04 μm aluminum thin film was previously laminated on the thermoplastic resin film layer (A-1) as a decorative layer (B) by vacuum deposition. Thus, a laminated sheet for molding (S-4) was obtained. The 20 ° gloss value of the sheet (S-4) was 1450%. Further, a molded body (M-4) was obtained in the same manner as in Example 1.
As a result of evaluating the molded product (M-4), the evaluation of moldability was ○, the mold reproducibility evaluation was ○, the 20 ° gloss value of the 110% developed portion was 1350%, and the gloss retention was 93%, 110%. The gloss evaluation of the developed part was ◎. Further, the 20 ° gloss value of the 150% developed portion was 650%, the gloss retention was 45%, and the gloss evaluation of the 150% developed portion was Δ.

(Example 5)
Without using the above-mentioned primer and high-gloss ink, the gravure printing ink “Univia NT” (Dainippon Ink) was used as the decoration layer (B) in advance on the decoration layer (B) side of the thermoplastic resin film layer (A-1). Example 3 except that a black grid pattern with an interval of 1 mm was printed on the first plate and a white solid pattern was printed on the second and third plates by a gravure printing method using In the same manner as above, a molding laminated sheet (S-5) was obtained. Further, a molded body (M-5) was obtained in the same manner as in Example 1.
As a result of evaluating the molded product (M-5), the evaluation of molding possibility was “good”, and the mold reproducibility evaluation was “good”. Further, at the development rate of 110%, almost no distortion of the grid pattern was observed, and at the development rate of 150%, the grid pattern itself was deformed, but almost no distortion of the ruled line was observed. Further, there was no significant difference in whiteness between the development rate of 110% and the development rate of 150%.

(Example 6)
A molded body (M-6) was obtained in the same manner as in Example 1 except that the sheet temperature at the start of molding was 100 ° C.
As a result of evaluating the molded product (M-6), the evaluation of molding feasibility was ○, the mold reproducibility evaluation was ○, the 20 ° gloss value of the 110% developed part was 1000%, and the gloss retention was 95%, 110% The gloss evaluation of the developed part was ◎. The 20 ° gloss value of the 150% developed portion was 850%, the gloss retention was 81%, and the gloss evaluation of the 150% developed portion was ◎.

(Example 7)
A molded body (M-7) was obtained in the same manner as in Example 1 except that the sheet temperature at the start of molding was 130 ° C.
As a result of evaluating the molded product (M-7), the evaluation of moldability was ○, the mold reproducibility evaluation was ◎, the 20 ° gloss value of the 110% developed portion was 650%, and the gloss retention was 62%, 110% The gloss evaluation of the developed part was ○. Further, the 20 ° gloss value of the 150% developed portion was 600%, the gloss retention was 57%, and the gloss evaluation of the 150% developed portion was Δ.

(Comparative Example 1)
A comparative molded body (M-1 ′) was obtained in the same manner as in Example 1 except that the molding temperature was 140 ° C. As a result of evaluating the comparative molded body (M-1 ′) by the same method as in Example 1, the evaluation of molding feasibility was ○, the mold reproducibility evaluation was ◎, the 20 ° gloss value of the 110% developed portion was 400%, and the gloss The retention rate was 38%, and the glossiness evaluation of the 110% developed portion was x. Further, the 20 ° gloss value of the 150% developed portion was 250%, the gloss retention was 24%, and the gloss evaluation of the 150% developed portion was x. In addition, a trace of the air vent hole remained at the joint between the top surface portion and the inclined surface of the molded body (M-1 ′), and a pressure trace when the sheet was sandwiched between the concave and convex shapes remained on a part of the top surface. .

(Comparative Example 1a)
Comparative molded body (M-1a ′) in the same manner as in Comparative Example 1 except that a black grid pattern having a 1 mm interval was previously printed on the decorative layer (B) side of the thermoplastic film layer (A-1). Got. Although the distortion of the ruled line was hardly recognized at the development rate of 110%, the grid pattern was slightly deformed, and the clear ruled line distortion was recognized at the development rate of 150%.

(Comparative Example 2)
The same sheet as in Example 1 was vacuum-formed only with a convex shape without using a movable frame clamp. The molding temperature was 140 ° C. to obtain a comparative molded body (M-2 ′). As a result of evaluating the comparative molded body (M-2 ′) in the same manner as in Example 1, the molding propriety evaluation was Δ, the mold reproducibility evaluation was ○, the 20 ° gloss value of the 110% developed portion was 300%, and the gloss retention rate. Was 29%, and the glossiness evaluation of 110% developed portion was x. Further, the 20 ° gloss value of the 150% developed portion was 200%, the gloss retention was 19%, and the gloss evaluation of the 150% developed portion was x.

(Comparative Example 2a)
Comparative molded body (M-2a ′) in the same manner as in Comparative Example 2 except that a black grid pattern with an interval of 1 mm was previously printed on the decorative layer (B) side of the thermoplastic film layer (A-1). Got. When the development rate was 110%, deformation of the grid pattern was recognized along with the ruled line distortion, and apparently non-uniform ruled line distortion was observed when the development rate was 150%.

(Comparative Example 3)
About the same sheet | seat as Example 1, the match mold shaping | molding was implemented using the concave type | mold and a convex type | mold, without using a movable frame-shaped clamp. In the same manner as in Example 1, the molding temperature was 115 ° C. to obtain a comparative molded body (M-3 ′). As a result of evaluating the comparative molded body (M-3 ′) in the same manner as in Example 1, the evaluation of molding feasibility was x, the mold reproducibility evaluation was Δ, the 20 ° gloss value at a development rate of 110% was 800%, and gloss retention The gloss ratio was 76%, and the glossiness evaluation at a development ratio of 110% was ◯. Further, the 20 ° gloss value at a development rate of 150% was 500%, the gloss retention was 48%, and the gloss evaluation at a development rate of 150% was Δ. Further, due to the drawing of the sheet during molding, a part of the sheet was released from the clamp of the molding machine, and chilled marks (cooling marks) due to contact between the sheet and the concave mold were generated on all the slopes of the molded body.

(Comparative Example 4)
For the same sheet as in Example 1, the movable frame clamp of the present invention was removed from the air cylinder, and only four rods (diameter 20 mm) of the air cylinder were operated to perform match mold molding under the same molding conditions as in Example 1. A comparative molded body (M-4 ′) was obtained. As a result of evaluating the comparative molded body (M-4 ′) in the same manner as in Example 1, the evaluation of molding feasibility was x, the mold reproducibility evaluation was Δ, the 20 ° gloss value at a development rate of 110% was 800%, and gloss retention The gloss ratio was 76%, and the glossiness evaluation at a development ratio of 110% was ◯. Further, the 20 ° gloss value at a development rate of 150% was 500%, the gloss retention was 48%, and the gloss evaluation at a development rate of 150% was Δ. Further, due to the drawing of the sheet during molding, a part of the sheet was released from the clamp of the molding machine, and chilled marks (cooling marks) due to contact between the sheet and the concave mold were generated on all the slopes of the molded body.

(Comparative Example 5)
For the same sheet as in Example 1, the short side portions of the movable frame clamps 14 and 24 are removed, and only two sides of the sheet can be fixed, and match mold molding is performed under the same molding conditions as in Example 1 for comparison. A molded product (M-5 ') was obtained. As a result of evaluating the comparative molded body (M-5 ′) in the same manner as in Example 1, the evaluation of moldability was ×, the mold reproducibility evaluation was Δ, the 20 ° gloss value at a development rate of 110% was 800%, and gloss retention The gloss ratio was 76%, and the glossiness evaluation at a development ratio of 110% was ◯. Further, the 20 ° gloss value at a development rate of 150% was 550%, the gloss retention was 52%, and the gloss evaluation at a development rate of 150% was Δ. In addition, sheet tearing occurred in a portion that was not clamped, and chilled marks (cooling marks) were generated on the two slopes on the side where sheet clamping was not possible during molding due to contact between the sheet and the concave mold.

(Comparative Example 6)
A comparative molded body (M-6 ′) was obtained in the same manner as in Example 5 except that the molding temperature was 140 ° C. As a result of evaluating the comparative molded body (M-6 ′) by the same method as in Example 5, the evaluation of molding feasibility was “○” and the mold reproducibility evaluation was “◎”. In addition, although the distortion of the ruled line was hardly recognized at the development rate of 110%, the grid pattern was slightly deformed, and the clear ruled line distortion was recognized at the development rate of 150%. Further, when the development rate was 150%, the base was seen through, and a difference in whiteness from the development rate of 110% was recognized. Further, a chilled mark (cooling mark) was generated on the part of the molded body (M-6 ′) near the top surface due to contact between the sheet and the convex mold.

(Summary)
Tables 1 and 2 summarize the main points and the evaluation results of the implementation conditions of the above examples and comparative examples.

In Examples 1 to 4, by using a movable frame clamp, match molding is performed at a relatively low temperature, the molded body is free of wrinkles, mold reproducibility is good, and the metallic luster of the decoration layer is maintained. I was able to.
In Example 5, the metallic luster layer was not used as the decorative layer, but a molded article having a good appearance with little change in color pattern was obtained.
In Comparative Example 1, by using the movable frame clamp, the molded body was free of wrinkles and good mold reproducibility was obtained, but the gloss retention was poor because the molding temperature was relatively high. It became.
In Comparative Example 2, when the vacuum molding was performed without the movable frame clamp and the concave mold, wrinkles of less than 3 mm were generated on the molded body. Further, in vacuum forming, the optimum temperature for forming is high, and the spreadability of the sheet is not uniform.
In Comparative Example 3, when the movable frame-shaped clamp was omitted and the match mold was formed, the sheet slack could not be sufficiently extended after the sheet was heated, and the sheet could not be pulled into the mold. As a result, a large number of wrinkles of 3 mm or more occurred in the molded body. In addition, the gloss retention of the 150% developed part was inferior because the spreadability of the sheet was non-uniform due to the same cause as described above.
In Comparative Examples 4 and 5, when match mold molding was performed using a movable clamp that was not a frame shape, the sheet slack after heating could be extended to some extent, but the effect of preventing the sheet from being pulled into the mold Was insufficient, so that molding flaws occurred frequently as in Comparative Example 3. Further, for the same reason as in Comparative Example 3, the gloss retention at the 150% developed portion was inferior.
In addition, in the case of a decorative sheet having a printed pattern as a decorative layer by comparing Examples 1a and 2a and Comparative Examples 1a and 2a, deformation of the printed pattern can be suppressed by performing match mold molding at a relatively low temperature. It was solved.
Further, the same results were obtained in comparison between Example 5 and Comparative Example 6 in which no metallic luster layer was used.

  The present invention is particularly useful for the production of molded articles that are used in applications such as automobile-related members, construction-related members, and household electrical appliances, have excellent decorative sharpness, and do not require outer layer coating. In particular, it is useful as a molding method and molding apparatus for a laminated sheet for molding having a specular metallic gloss.

It is typical sectional drawing explaining the shaping | molding method A of the 1st form example of the shaping | molding method of this invention, (a) is the state which clamped and fixed the sheet | seat with the frame-shaped clamp, (b) is the sheet | seat clamped and fixed on one side The state in contact with the mold, (c) shows the state in which the clamped and fixed sheet is clamped with both molds. It is typical sectional drawing explaining the shaping | molding method B of the 1st example of the shaping | molding method of this invention, (a) is the state which clamped and fixed the sheet | seat with the frame-shaped clamp, (b) is the sheet | seat fixed by clamping one side. The state in contact with the mold, (c) shows the state in which the clamped and fixed sheet is clamped with both molds. It is typical sectional drawing explaining the 2nd example of the shaping | molding method of this invention, (a) is the state which clamped and fixed the sheet | seat with the frame-shaped clamp, (b) contacted the sheet | seat clamped and fixed to one metal mold | die. (C) shows a state where the sandwiched and fixed sheet is clamped by both molds. It is a perspective view which shows an example of the convex type | mold which provided the frame-shaped clamp, (a) is the state which lowered | hung the frame-shaped clamp with respect to the metal mold | die, (b) is the state which raised the frame-shaped clamp with respect to the metal mold | die. Indicates. It is a perspective view which shows an example of the concave mold | type which provided the frame-shaped clamp, (a) is the state which lowered the frame-shaped clamp with respect to the metal mold | die, (b) is the state which raised the frame-shaped clamp with respect to the metal mold | die. Show. It is a perspective view which shows the other example of the concave type | mold which provided the frame-shaped clamp, (a) is the state which lowered | hung the frame-shaped clamp (it is notched and shown in figure) with respect to a metal mold | die, (b) Indicates a state in which the frame-shaped clamp is raised with respect to the mold. It is the schematic which shows an example in case the frame-shaped clamp has a recessed part and a convex part which mutually fit in the shaping | molding apparatus of a 1st form example. It is the schematic which shows an example in case the frame-shaped clamp has a recessed part and a convex part which mutually fit in the shaping | molding apparatus of a 2nd form example. It is the schematic which shows the other example in case a frame-shaped clamp has a recessed part and a convex part which mutually fit in the shaping | molding apparatus of a 2nd form example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Thermoforming sheet | seat, 2 ... The part which should mold-mold, 10 ... Convex type, 11 ... Convex-type main body, 12 ... Box, 13 ... Fixed plate, 14 ... Frame clamp, 15 ... Clamp surface, 17 ... Convex Outer peripheral edge of mold, 18 ... vacuum hole, 20 ... concave mold, 21 ... concave body, 22 ... box, 23 ... fixing plate, 24 ... frame clamp, 25 ... clamp surface, 27 ... flange, 31 ... convex, 32 ... concave portion.

Claims (11)

A method for thermoforming a sheet for thermoforming in which one or more thermoplastic resin layers (A) and a decorative layer (B) are laminated, between a pair of molds,
According to JIS K7244-1 method, when dynamic viscoelasticity is measured under the measurement conditions of frequency 1 Hz, measurement start temperature 0 ° C., temperature increase rate 3 ° C./min, when the mechanical attenuation shows a maximum value. When the temperature is the glass transition temperature (Tg),
A part of the thermoforming sheet including a portion to be molded is taken as a glass transition temperature (Tg (A)) of the thermoplastic resin layer (A) (however, the thermoforming sheet is made of the thermoplastic resin layer (A). ) In a plurality of layers, the highest glass transition temperature of the plurality of thermoplastic resin layers (A) is defined as Tg (A)), with respect to (Tg (A) -30) ° C. to (Tg ( A) After heat plasticization within the temperature range of +10) ° C.,
The entire circumference of the portion to be molded of the thermoforming sheet is clamped and fixed from both sides of the thermoforming sheet using a pair of frame clamps,
By pressing a part of one mold against one surface of the heat plasticized part, the heat plasticized part is stretched between the one mold and the frame clamp,
After that, the other mold is brought into contact with the heat plasticized portion from the direction opposite to the surface of the heat plasticized portion with which the one mold contacts,
A method for forming a thermoforming sheet, wherein the heat-plasticized portion is sandwiched and formed by the one mold and the other mold.   The method for molding a thermoforming sheet according to claim 1, wherein the one mold is a convex mold and the other mold is a concave mold.   The method for molding a thermoforming sheet according to claim 1, wherein the one mold is a concave mold and the other mold is a convex mold. Using the frame-shaped clamp in which the inner peripheral edge of the concave frame-shaped clamp is inside the inner peripheral edge of the convex-shaped frame clamp,
At least a part of one mold is pressed against the heat plasticized portion inside the frame-shaped clamp to extend the heat-plasticized portion between the one mold and the frame-shaped clamp. At the time, in a state where the thermoforming sheet is sandwiched and fixed between the inner peripheral edge of the frame-shaped clamp on the concave side and the outer peripheral edge of the convex mold, the heat-plasticized portion is vacuumed from the convex mold side. The method for forming a thermoforming sheet according to claim 2, wherein suction is performed.   In the thermoforming sheet, a transparent or translucent thermoplastic resin layer (A-1), a decorative layer (B), and a thermoplastic resin layer (A-2) serving as a supporting substrate are laminated in this order. When the temperature at which the heat plasticization is performed represents the higher glass transition temperature of the layer (A-1) and the layer (A-2) as (Tg (A-M)), 2. The method for forming a thermoforming sheet according to claim 1, which is within a temperature range of Tg (A−M) −30) ° C. to (Tg (A−M) +10) ° C. 3.   The method for forming a thermoforming sheet according to claim 1, wherein the decorative layer (B) is a metallic decorative layer made of an ink film in which metal thin film strips are dispersed in a binder resin. According to JIS K7244-1 method, when dynamic viscoelasticity is measured under the measurement conditions of frequency 1 Hz, measurement start temperature 0 ° C., temperature increase rate 3 ° C./min, when the mechanical attenuation shows a maximum value. When the temperature is the glass transition temperature (Tg),
A portion of the thermoplastic resin layer (A) including a portion to be mold-molded of one or more thermoplastic resin layers (A) and a decorative layer (B) is laminated on the glass of the thermoplastic resin layer (A). Transition temperature (Tg (A)) (However, when the thermoforming sheet has a plurality of the thermoplastic resin layers (A), the highest temperature among the glass transition temperatures of the plurality of thermoplastic resin layers (A) is Tg. (A)), after heat plasticizing within a temperature range of (Tg (A) -30) ° C. to (Tg (A) +10) ° C., the mold for the thermoforming sheet should be molded. It is a device that molds by contacting a pair of molds on both sides of the part,
A frame-like clamp that holds and fixes the entire periphery of the portion to be molded of the thermoforming sheet is provided around each die, and the frame-like clamp is relatively movable with respect to the die. An apparatus for forming a thermoforming sheet.   The said frame-shaped clamp is a shaping | molding apparatus of the sheet | seat for thermoforming of Claim 7 supported by the fixed plate common to the said metal mold | die.   The inner peripheral edge of the concave frame clamp is located inside the inner peripheral edge of the convex frame clamp, and the gap between the inner peripheral edge of the concave frame clamp and the outer peripheral edge of the convex mold. The thermoforming sheet according to claim 7 or 8, wherein the thermoforming sheet is configured to be clampable, and the convex mold has a vacuum hole for sucking the thermoforming sheet from the convex mold side using vacuum. Molding equipment.   The frame-shaped clamp has a concave portion and a convex portion that are fitted to each other on the surface for sandwiching and fixing the thermoforming sheet. When the thermoforming sheet is sandwiched and fixed between the two frame-shaped clamps, The molding apparatus for a thermoforming sheet according to any one of claims 7 to 9, wherein the convex portion protruding from the clamp can be fitted into a concave portion provided in the other frame-shaped clamp.   In the thermoforming sheet, a transparent or translucent thermoplastic resin layer (A-1), a decorative layer (B), and a thermoplastic resin layer (A-2) serving as a supporting substrate are laminated in this order. When the temperature at which the heat plasticization is performed represents the higher glass transition temperature of the layer (A-1) and the layer (A-2) as Tg (A-M), (Tg ( The thermoforming sheet molding apparatus according to any one of claims 7 to 10, which is within a temperature range of (A-M) -30) ° C to (Tg (AM) +10) ° C.

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