JP5845403B2 - Film decoration parts - Google Patents

Description

  The present invention relates to a decorative molded part in which a film is bonded and decorated by vacuum forming or vacuum / pressure forming.

  As a means for improving the appearance quality of a molded part, decorating the appearance surface with a film having a design property is performed. Generally, methods for decorating a molded product having a three-dimensional shape include vacuum molding or vacuum / pressure forming, insert molding, and in-mold molding.

  Vacuum forming is to soften the film by applying heat and drawing the air between the film and the molded product from the component side to create a state close to vacuum and to adhere to the component. Further, the air pressure is applied from the film side on the upper part of the component (hereinafter referred to as vacuum forming). In insert molding, a film is shaped in advance, inserted into a mold, heated molten resin is applied under pressure (injection molding), cooled and solidified, and the film and molded product are integrated. This is a method for producing a component. Further, in-mold molding is performed by inserting a film with design printing into a mold through a release layer, injection molding and cooling and solidifying, and then peeling the film to transfer the design to produce an integrated part. Is the method.

  The insert molding and in-mold molding are characterized by being decorated at the same time as the molding of the part and firmly integrated. On the other hand, vacuum forming is a method of decorating by bonding a heated film after completion of a molded part (for example, Patent Document 1).

Japanese Patent No. 3924760

  However, in the vacuum forming method, the resin film that has been softened by heating to about 100 to 200 ° C. is stretched and bonded to a molded part at room temperature (hereinafter, a decorated part), and then cooled, the film shrinks, A large internal stress is generated in the decorated part. This is a stress resulting from the difference in internal shrinkage between the film orientation and the heat shrinkage ratio between the heating film and the part to be decorated.

  There has been a problem that dimensional changes such as deformation of the molded product occur due to the stress inherent in the film molded body.

  In order to suppress this, the structural strength is ensured by increasing the thickness of the part to be decorated or combining it with another member.

  In addition, if a flexible film (for example, with low orientation) is used, the internal stress can be reduced and the dimensional change can be suppressed. However, the soft and soft film has a low surface hardness, and even an HB pencil can be scratched. Therefore, a flexible film cannot be used.

The present invention has been made to solve such a problem, and when a predetermined ABS molded base and a predetermined surface hardness are desired, the storage elastic modulus of the film is 5 MPa or more and 30 MPa or less at 130 ° C. It aims at providing the film decorative component which suppressed the dimensional change by doing.

  In order to solve the above-mentioned conventional problems, the film decorative molded part of the present invention is a part decorated by vacuum forming or vacuum / pressure forming, and has a thickness of 1.0 mm or more and 2.5 mm or less constituting the part main body. A decorative film part having an ABS molded base material, a film harder than pencil hardness HB covering the molded base material, and an adhesive layer between the molded base material and the film, The hem is exposed to the design surface of the molded substrate, and the storage elastic modulus of the film is 5 MPa or more and 30 MPa or less at 130 degrees Celsius.

  Here, the storage elastic modulus is based on JIS K7244-1 and 7244-4, and a sheet having a test piece width of 5 mm and a length of 20 m is started at a temperature of 25 ° C., an end temperature of 160 to 200 ° C., and a rate of temperature increase of 2 ° C. / This is a value measured under conditions of a minute and a measurement frequency of 1 Hz.

  As a result, even when decorative molding is performed on a member whose end face portion (trimming peripheral portion) is not fixed, the internal stress of the film decorative molded body can be reduced, and dimensional changes such as warping of the film decorative component can be suppressed.

  The film decorative molded part of the present invention can realize dimensional stability by suppressing internal stress while ensuring surface hardness.

Whole perspective view of the vacuum cleaner in Embodiment 1 of this invention The perspective view of the vacuum cleaner main body in Embodiment 1 of this invention, and a dust cover Sectional drawing of the film decorating components in Embodiment 1 of this invention Sectional drawing explaining the film decoration process in Embodiment 1 of this invention Sectional drawing explaining the film decoration process in Embodiment 1 of this invention Sectional drawing explaining the film decoration process in Embodiment 1 of this invention

  The first invention comprises an ABS molded base material having a thickness of 1.0 mm or more and 2.5 mm or less constituting a component main body, a film harder than pencil hardness HB covering the molded base material, and the molded base material, A decorative film part having an adhesive layer between the film and the hem of the film is exposed on the design surface of the molded substrate, and the storage elastic modulus of the film is 5 MPa at 130 ° C. Above and below 30 MPa.

  Here, the film decorative part is a part in which a film having a design property is adhered by vacuum forming, and the hem part of the film is a part of the cut line after removing the excess film after vacuum forming, The design surface is a surface that is touched by human eyes.

  If the storage elastic modulus of the film at 130 degrees Celsius is less than 5 MPa, the surface hardness of the film decorative part is low and easily damaged, and if it is greater than 30 MPa, the internal stress after molding is large, The dimensional change, particularly the dimensional change at the bottom of the film, becomes large.

  On the other hand, even if the ABS molded substrate is a thin member having a thickness of 1.0 to 2.5 mm, if the storage elastic modulus of the film is 5 to 30 MPa at 130 ° C., the surface pencil hardness HB It is harder than or equal to and can suppress the dimensional change of the skirt of the film.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
As an example of an embodiment of a film decorative component, a case where a dust cover of a vacuum cleaner is decorated with a film will be described.

  FIG. 1 is a perspective view of the cleaner according to the first embodiment of the present invention, FIG. 2 is a perspective view of the cleaner body with the dust cover open, and FIG. 3 is the dust cover of FIG. FIG. 3 is a cross-sectional view taken along the X plane.

  In FIG.1 and FIG.2, the cleaner body 1 has the shaping | molding base material 2 which comprises a dust cover. The dust cover is a lid for taking out the dust scraps sucked by the vacuum cleaner, and can be freely opened and closed. Further, the molded base 2 is decorated with a decorative film 3 and constitutes a film decorative component 4.

  Here, since the film decoration component 4 is a component that opens and closes, the cut portion of the film does not hide inside, but appears on the surface that can be seen by human eyes.

  Hereinafter, the film decoration method of the dust cover which is the film decoration component 4 is demonstrated.

  The decorative film 3 to be used is characterized in that the storage elastic modulus is 5 to 30 MPa at 130 ° C. When the film is a laminated film, the storage elastic modulus of each film does not need to be the above value, and the value as a laminated film may be as described above.

  Each film needs to be a resin film that is softened by heating. For example, acrylic (polymethyl methacrylate, polyethyl methacrylate, polypropyl methacrylate, polybutyl methacrylate, etc.), ABS (acrylonitrile-butadiene- Styrene), PC (polycarbonate), polyester (polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycyclohexyldimethylene terephthalate, etc.), polyolefin, and the like.

  As an outermost layer film, an acrylic film is excellent in terms of transparency, scratch resistance, and weather resistance, and thus is preferable as a film used for the outermost layer for decoration purposes. Moreover, when using an acrylic film, it is desirable to laminate | stack an ABS film from the point of storage elastic modulus.

  In the printing method for the decorative film 3, gravure printing, silk screen printing, offset printing, and the like can be used, and can be selected depending on the required design of appearance, printability on the film, and the number of films produced.

  Examples of the adhesive layer include a hot melt system, a pressure sensitive system, a reactive type, and the like, but a pressure sensitive type is desirable because of its ability to follow a three-dimensional shape. Moreover, since the pressure sensitive system can be bonded and peeled off at room temperature, it is easy to cut off (trim) the excess film. Furthermore, since peeling occurs at the interface with the molding substrate at the time of peeling, there is an advantage that no adhesive remains on the surface of the molding substrate and the appearance quality is not impaired.

  Here, the material of the adhesive layer is not particularly specified, and examples thereof include acrylic, silicone, rubber, and urethane. In particular, an acrylic resin having excellent adhesion, weather resistance, heat resistance, and solvent resistance is desirable.

  The molding substrate 2 is an ABS resin having a wall thickness of 1.0 to 2.5 mm, and is excellent in mechanical strength (surface hardness), surface smoothness (sink is unlikely to occur), and the like.

  Using the above materials, film decoration can be performed by a general vacuum / pressure forming method. Next, the film decoration process will be described.

  First, as shown in FIG. 4, the receiving jig 11 on which the molding substrate 2 is placed is placed on the lower table 13 in the lower box 12, and the decorative film 3 is set on the upper surface of the lower box 12. Thereafter, the upper box 14 is lowered to make the upper and lower boxes airtight.

  And the inside of an upper and lower box is made into a vacuum state (decompression state) with the vacuum pump 15 (arrow), the heater 16 is turned on, and the decoration film 3 is heated.

  When the temperature reaches a predetermined temperature at which the decorative film 3 softens, the lower table 13 in the lower box 12 rises as shown in FIG. 5, and the molding substrate 2 comes into contact with the decorative film 3. Thereafter, by opening the vacuum of the upper box 14 to an atmospheric pressure state, the decorative film 3 can be uniformly pressed against the molding substrate 2 by the atmosphere, and thereby the coating can be applied along the shape. At this time, the decorative film 3 can be brought into close contact with the molded substrate 2 with a larger force by putting compressed air from the compressed air tank 17 into the upper box 14.

  Then, the heater 16 is turned off and cooled. As shown in FIG. 6, the inside of the lower box 12 is returned to the atmospheric pressure state, and the upper box 14 is raised.

  After that, along the protruding portion of the molding substrate 2, a cutting line is cut from the side by the cutting jig 18 to perform trimming. As a result, the protrusions serve as guides, and the excess film can be removed with good workability in a single process. It is also possible to perform rough cutting in the box, take it out of the box, fix it to a trimming jig or the like, and perform trimming. The cutting jig 18 used for trimming only needs to be able to cut a resin film. For example, a sharp metal cutter (cutter), a hot knife, an ultrasonic cutter, a laser, or the like can be used.

  Hereinafter, the result derived by experiment about the storage elastic modulus of a film is demonstrated.

The molding base material 2 used for the experiment was a rectangular flat plate made of ABS resin with a side of 100 mm, and the thickness was 0.5 mm, 1.0 mm, 2.5 mm, or 3.5 mm. The decorative film 3 is a laminated film of acrylic and ABS, and the total thickness of the film including the adhesive layer is 0.3 to 0.4 mm.

  The storage elastic modulus as a laminated film was changed by changing the thickness of each film of acrylic and ABS and the grade of the film. The storage elastic modulus of the obtained laminated film was 1 MPa, 5 MPa, 30 MPa, and 80 MPa at 130 degrees Celsius.

  The decoration was formed at 140 ° C. by the above-described vacuum / pressure forming method, and trimmed with the same dimensions as the flat plate to obtain an evaluation sample.

  In the evaluation, the amount of warpage of the flat plate was determined by using a gap gauge having a thickness of 0.80 mm and 0.50 mm in accordance with JIS7524. That is, if the gap is equal to or less than 0.50 mm, the dimensional change is ○, if the gap is equal to or less than 0.80 mm, the dimensional change is Δ, and if the gap is greater than 0.80 mm, the dimensional change is ×. Here, the clearance of 0.8 mm is a value that can be calculated from the clearance required to open and close, for example, when the film decorative part is a dust cover of a vacuum cleaner.

  Further, the evaluation sample was marked with ○ when the pencil hardness was equal to or higher than HB (no scratching with HB), and x when the pencil hardness was softer than HB.

  Here, as described above, the storage elastic modulus is based on JIS K7244-1 and 7244-4, and the temperature of the sheet having a test piece width of 5 mm and a length of 20 m is increased at a rate of 2 ° C./min, and at 130 ° C. It is a measured value, and the pencil hardness is a value measured according to JIS K5600-5-4.

  The experimental results are shown in Tables 1 and 2.

  As shown in the experimental results, when the thickness of the ABS molded substrate is 0.5 mm, a dimensional change occurs even if the storage elastic modulus of the film is as small as 1 MPa. Further, the pencil hardness does not depend on the thickness of the ABS molded base material, and depends on the storage elastic modulus of the film.

Next, with respect to each storage elastic modulus, dimensional change, and pencil hardness, when the storage elastic modulus is 5 MPa, the dimensional change is suppressed when the thickness of the ABS molded substrate is 1.0 mm to 2.5 mm, and the pencil hardness is reduced. Is equal to or better than HB. Even when the storage elastic modulus is as large as 30 MPa, the dimensional change is small and the pencil hardness is equal to or higher than that of HB when the thickness of the ABS molded substrate is between 1.0 mm and 2.5 mm. However, when the storage elastic modulus is 80 MPa, the dimensional change is large even when the thickness of the ABS molded substrate is 2.5 mm (the dimensional change is ◯ at the thickness of 3.5 mm).

  Considering the above factors, if the storage modulus of the film is reduced to 5 MPa, the internal stress derived from the orientation of the film is reduced, so the stress (warping force) on the flat plate due to film shrinkage after molding is reduced. Even if the thickness of the flat plate is 1.0 mm, the dimensional change is difficult to occur. On the other hand, when the storage elastic modulus of the film is 80 MPa, the internal stress of the film is large, so the ABS resin physical properties and the resistance as a structure depending on the thickness of the flat plate are 2.5 mm, and the dimensional change occurs. It will be. In addition, the film having a storage elastic modulus of 1 MPa is presumed to have a result that the pencil core for measuring the pencil hardness is likely to sink due to its low elasticity and is easily damaged.

  As described above, the decorative film part according to the present invention can be applied to a part with improved appearance design. For example, it can be used for household appliances such as a vacuum cleaner, an air conditioner, a warm water washing toilet seat, a refrigerator, and a washing machine. Furthermore, the configuration of the present invention is particularly suitable for a part that moves like a part that the film decorative part opens and closes, and that the film hem part touches the human eye. For example, it can be used for a dust cover of a vacuum cleaner or a panel of an air conditioner.

DESCRIPTION OF SYMBOLS 1 Vacuum cleaner main body 2 Molding base material 3 Decorating film 4 Film decorating part 11 Receiving jig 12 Lower box 13 Lower table 14 Upper box 15 Vacuum pump 16 Heater 17 Pressure air tank 18 Cutting jig

Claims (1)

It is a part that is decorated by vacuum forming or vacuum / pressure forming, and has a thickness of 1.0 mm or more and 2.5 mm or less constituting the part body, and a pencil hardness HB that covers the forming base is equal to or higher than that. A decorative film part having a hard film and an adhesive layer between the molded substrate and the film, wherein the hem of the film is exposed on the design surface of the molded substrate, A film decorative part having a storage elastic modulus of 5 MPa to 30 MPa at 130 ° C.