JP4578128B2 - Plastic molded product - Google Patents

Description

  The present invention relates to a resin molded product provided with a decorative sheet for insert on the surface, and particularly relates to a resin molded product with less flow or peeling of a decorative part in the decorative sheet for insert during insert molding.

Conventionally, insert molding using a decorative sheet for insert has been widely employed as a method for producing a decorated resin molded product. More specifically, after forming a decorative portion and a binder layer on the base material to obtain a decorative sheet, it is mounted in a mold, and an injection molding machine or the like is used to inject molten resin, A resin molded product having a decorative sheet on the surface can be obtained.
However, in order to firmly laminate the decorative sheet on the surface of the resin molded product, it is effective to heat the decorative sheet above its softening point when injecting the molten resin. When is made of a thermoplastic resin, there have been problems that laminar flow occurs or the mold does not accurately follow due to a decrease in strength.

Therefore, a thermoplastic film (base material) having a thickness of 0.02 to 0.8 mm, a colored layer (decoration part) showing a softening temperature higher than the softening temperature of the thermoplastic film, and adhesiveness at room temperature. A laminate having a thickness of 0.2 to 20 mm including a polyurethane layer not shown and a thermoplastic layer having a thickness of 0.1 to 19 mm is disclosed (see Patent Document 1).
Further, as shown in FIGS. 5 and 6, a decorative sheet 102 including a decorative portion 105 having a specific breaking strength and breaking elongation is provided on a thermoplastic resin sheet 104 with ultraviolet curable coloring ink. A resin molded product 103 or a resin molded product 103 further provided with a binder layer 106 on the back surface of the decorative sheet 102 is disclosed (see Patent Documents 2 and 3). More specifically, an ultraviolet curable colored ink is composed of a urethane-based (meth) acrylate oligomer, a monofunctional acrylic monomer, a photopolymerization initiator, a carbon black pigment, and the like, and an additive composed of the ultraviolet curable colored ink. A resin molded article is disclosed in which a decorative part is a film having a thickness of 100 μm and includes a decorative sheet having a breaking strength of 1.0 kg / cm or more and a breaking elongation of 130% or more at 25 ° C.
JP-A-8-25599 (Claims) JP 2003-145574 A (Claims, FIG. 1) Japanese Patent Laying-Open No. 2003-326591 (Claims, FIG. 1)

However, the laminate disclosed in Patent Document 1 must be provided with a colored layer (decorating portion) having a softening temperature higher than the softening temperature of the thermoplastic film. However, there is a problem that it is difficult to follow the forming die with high accuracy because of excessive limitation or a decrease in elongation at break. Also, if a colored layer having a softening temperature higher than the softening temperature of the thermoplastic film is provided, the value of elongation at break decreases significantly when the amount of pigment added in the colored layer is increased, and insert molding is performed. Moreover, the problem that it was easy to peel between the thermoplastic film in a decorating sheet and a colored layer was also seen. Furthermore, although a colored layer may be made into a multilayer structure, when the softening temperature of the colored layer was high, the problem that it was easy to peel between the colored layers which comprise a multilayer structure was also seen.
Moreover, since the resin molded product provided with the decorating sheet disclosed in Patent Documents 2 and 3 does not consider the relationship between the softening temperature of the base material and the softening temperature of the decorating part, the decorating part. There was a problem that the value of breaking strength and elongation at break must be strictly limited. Conversely, simply limiting the values of the breaking strength and elongation at break of the decorative part to the specified ranges in this way, the flow and peeling of the decorative part in the decorative sheet are effective during insert molding of the decorative part. It was difficult to prevent. That is, when the amount of pigment added in the decorative part is increased, the value of elongation at break is remarkably lowered, and the insert film is easily peeled between the thermoplastic film and the colored layer in the decorative sheet. There was also a problem.

Therefore, unlike the conventional knowledge, the inventors of the present invention have a softening temperature that is lower than the softening temperature of the substrate and within a predetermined range, and the decorative portion is formed from the three-dimensional crosslinked product of the ultraviolet curable composition. By forming, the flow and peeling of the decorative part is reduced, and it is found that even when the amount of pigment added in the decorative part is increased, the decrease in the elongation at break is reduced, and the present invention It came to complete.
That is, the purpose of the present invention is the case where there is little flow or peeling of the decorative part in the insert decorative sheet during insert molding, and when the amount of pigment added is increased or a multilayer structure is used. Furthermore, it is to provide a resin molded product that can obtain a high elongation at break without peeling.

According to the present invention, there is provided a resin molded product having a decorative sheet for insert including a base material and a decorative portion on the surface, and a binder is provided between the surface of the resin molded product and the decorative portion. Layers, the softening temperature of the base material is T1 (° C.), the softening temperature of the decorative portion is T2 (° C.), and the softening temperature of the binder layer is T3 (° C.). T1) is a value within the range of 95 to 140 ° C., and the softening temperature (T2) of the decorative portion is a value within the range of 35 to 100 ° C.,
While satisfying the relationship of T2 + 100>T1> T2 + 10,
T1-T2 is set to a value within the range of 20 to 90 ° C.
And satisfies the relationship of T2 + 100>T3> T2 + 10,
Furthermore, the decorative part is formed from a three-dimensional cross-linked product of an ultraviolet curable composition containing at least a urethane acrylate oligomer, a reactive vinyl monomer, and a photopolymerization initiator, and the main component of the resin molded product is A resin molded product characterized in that it is an ABS resin or a polycarbonate resin and the binder layer contains a mixture of a polyester resin and a polyurethane resin is provided, and the above-mentioned problems can be solved.

  Further, in constituting the resin molded product of the present invention, the decorative portion includes a urethane acrylate oligomer having a number average molecular weight of 1,000 or more, a reactive vinyl monomer, and a photopolymerization initiator, and urethane acrylate. It is preferable that the weight ratio of the oligomer and the reactive vinyl monomer is a three-dimensionally crosslinked product of an ultraviolet curable composition having a value within a range of 1: 1 to 1: 3.

  Further, in constituting the resin molded product of the present invention, the ultraviolet curable composition contains titanium oxide, and the addition amount of the titanium oxide is in the range of 1 to 40 parts by weight with respect to 100 parts by weight of the urethane acrylate oligomer. It is preferable to set the value within the range.

  Further, in constituting the resin molded product of the present invention, the binder layer contains silica particles, and the content of the silica particles is in the range of 5 to 50 parts by weight with respect to 100 parts by weight of the main component of the binder layer. It is preferable to set the value within the range.

  Moreover, when comprising the resin molded product of this invention, it is preferable that a binder layer contains the mixture of a polyester resin and a polyurethane resin.

  In constituting the resin molded product of the present invention, the main component of the resin molded product is preferably an ABS resin or a polycarbonate resin.

According to the resin molded product of the present invention, the softening temperature (T1) of the base material and the softening temperature (T2) of the decorative portion satisfy a predetermined relationship, and the decorative portion is formed from a predetermined object. Thereby, the flow, peeling, etc. of the decoration part in the decorative sheet for inserts at the time of insert molding can be reduced. In addition, by satisfying such a relationship, the occurrence of cracking and peeling of the decorative part during insert molding is reduced, and the amount of pigment added is high, for example, 30% by weight or more based on the total amount Even when added, high elongation at break can be achieved.
Moreover, according to the resin molded product of the present invention, by setting the softening temperature (T2) of the decorative portion to a value within a predetermined range, it becomes easier to satisfy a predetermined relationship with the softening temperature (T1) of the base material. Moreover, the flow of a decoration part, peeling, etc. in the decorative sheet for inserts at the time of insert molding can be reduced.
Furthermore, according to the resin molded product of the present invention, the binder layer is included at a predetermined location, and the softening temperature (T3) of the binder layer satisfies the predetermined relationship, so that the space between the decorative portion and the resin molded product is satisfied. It is possible to improve the adhesion. Furthermore, since the predetermined decorative portion is formed between the base material having the predetermined softening temperature and the binder layer, the flow and peeling of the decorative portion in the insert decorative sheet at the time of insert molding Etc. can be further reduced.

  Further, according to the resin molded product of the present invention, the decorative portion is formed from a three-dimensional cross-linked product of an ultraviolet curable composition containing a urethane acrylate oligomer or a reactive vinyl monomer having a predetermined average molecular weight in a predetermined ratio. As a result, the manufacturing apparatus can be reduced in size, and the flow and peeling of the decorative portion in the decorative sheet for insert during insert molding can be further reduced.

  Moreover, according to the resin molded product of the present invention, by including titanium oxide, and by setting the addition amount of the titanium oxide to a value within a predetermined range, the decorative part in the decorative sheet for inserts at the time of insert molding The flow and peeling can be further reduced. Moreover, in a decoration part, concealment property and decoration property can be improved by including a predetermined amount of titanium oxide.

Further, according to the resin molded product of the present invention, the binder layer contains hydrophobic silica particles, and the addition amount of the hydrophobic silica particles is set to a value within a predetermined range, whereby the heat resistance and water resistance of the binder layer are increased. Can be improved.
Further, by containing silica particles in this way, fine irregularities can be formed on the surface, so that the adhesion with the molding resin injected during injection molding can be improved.

  Moreover, according to the resin molded product of the present invention, the binder layer contains a predetermined resin mixture, whereby the heat resistance of the binder layer can be further improved, and fine irregularities can be uniformly formed on the surface. Can do.

  Moreover, according to the resin molded product of this invention, since the main component of a resin molded product is predetermined resin, the adhesiveness between a decorating part and a resin molded product can be improved. Furthermore, the moldability of the resin molded product can be further improved.

[First embodiment]
1st Embodiment equips the surface with the decorating sheet 14 for inserts containing the base material 10, the decorating part 12, and the binder layer 13 so that it may illustrate in FIG.1 (b)-(c). When the softening temperature of the base material is T1 (° C.) and the softening temperature of the decorative part is T2 (° C.), the relationship of T2 + 100>T1> T2 + 10 is satisfied, and The decorative part is a resin molded product formed from a three-dimensional cross-linked product of an ultraviolet curable composition. More specifically, it is a resin molded product provided with a decorative sheet for insert including a base material and a decorative part on the surface, and a binder is provided between the surface of the resin molded product and the decorative part. Layers, the softening temperature of the base material is T1 (° C.), the softening temperature of the decorative portion is T2 (° C.), and the softening temperature of the binder layer is T3 (° C.). T1) is a value within the range of 95 to 140 ° C., and the softening temperature (T2) of the decorative portion is a value within the range of 35 to 100 ° C.,
While satisfying the relationship of T2 + 100>T1> T2 + 10,
T1-T2 is set to a value within the range of 20 to 90 ° C.
And satisfies the relationship of T2 + 100>T3> T2 + 10,
Furthermore, the decorative part is formed from a three-dimensional cross-linked product of an ultraviolet curable composition containing at least a urethane acrylate oligomer, a reactive vinyl monomer, and a photopolymerization initiator, and the main component of the resin molded product is , An ABS resin or a polycarbonate resin, wherein the binder layer contains a mixture of a polyester resin and a polyurethane resin .
1A is a configuration example that does not include the binder layer in the decorative sheet for insert 14, and FIG. 1B is a configuration example that includes the binder layer 13 in the decorative sheet for insert 14. Yes, FIG. 1C is a configuration example that further includes a second decorative portion 12 ′.

1. The decorative sheet for insert (1) base material The kind of the base material 10 illustrated in FIG. 1 is not particularly limited. For example, a thermoplastic resin mainly composed of a polyester resin or a polycarbonate resin, or these thermoplastic resins. It is preferable that it is a transparent thermoplastic resin which consists of a poromer alloy which mixed other thermoplastic resin and thermosetting resin with respect to resin.
Moreover, regarding the value of the softening temperature (T1) of the base material, a relationship with T2 described later is satisfied, and specifically, a value within a range of 95 to 140 ° C. is set.
The reason for this is that when the softening temperature (T1) of the base material is less than 95 ° C. , the decorative sheet shrinks or deforms due to the irradiation heat during ultraviolet curing or the heat during solvent drying. This is because the decorative portion may be displaced from a predetermined position during molding.
On the other hand, if the softening temperature (T1) of the base material exceeds 140 ° C., it cannot follow the mold with high accuracy, and it may be difficult to obtain a molded product having a desired shape. .
Therefore, regarding the softening temperature (T1) of a base material, it is more preferable to set it as the value within the range of 100-135 degreeC.
Further, the thickness of the base material is preferably determined in consideration of the use and configuration of the resin molded product, but specifically, it is preferably set to a value in the range of 0.05 to 5 mm. More preferably, the value is in the range of 1 to 2 mm.

(2) Decorating part Moreover, when the softening temperature of the base material 10 illustrated in FIG. 1 is T1 (° C.) and the softening temperature of the decorating part 12 is T2 (° C.), the relationship of T2 + 100>T1> T2 + 10 It is characterized by satisfying.
That is, when the softening temperature (T1) of the base material and the softening temperature (T2) of the decorative portion satisfy a predetermined relationship, the flow and separation of the decorative portion in the decorative sheet for inserts during insert molding This is because it is possible to reduce the number of the like. Moreover, it is because satisfying such a relationship can achieve a high elongation at break even when the amount of the pigment added to the decorative portion is made high.
Moreover, regarding the value of the softening temperature (T2) of this decoration part, while satisfying the relationship with T1 mentioned above, it is specifically taken as the value within the range of 35-100 degreeC.
The reason for this is that when the softening temperature (T2) of the decorative part is less than 35 ° C., the position of the decorative part may be shifted from a predetermined position or thermally deformed during insert molding. is there.
On the other hand, when the softening temperature (T2) of the decorative part exceeds 100 ° C., it may be difficult to accurately follow the mold or may be easily peeled off from the base material. It is.
Therefore, regarding the softening temperature (T2) of the decoration part, it is more preferable to set it as the value within the range of 45-90 degreeC, and it is more preferable to set it as the value within the range of 50-85 degreeC.

Here, with reference to FIG. 2, the relationship between (T1-T2) and the flowability and adhesion of the decorating part will be described in detail with a solid line and a dotted line, respectively. The horizontal axis of FIG. 2 shows (T1-T2) (° C.), the left vertical axis shows the flowability evaluation (relative value) of the decorative portion, and the right vertical axis Shows the adhesion evaluation (relative value) of the decorative portion. As shown by the solid line, the larger the difference of (T1−T2), the better the value of the flowability evaluation. However, when the value becomes excessively large, for example, 100 ° C. There is a tendency to decrease. Moreover, as the dotted line shows, the larger the difference of (T1-T2), the better the value of the adhesion evaluation. However, when the value becomes excessively large, for example, 120 ° C. or higher, the value of the adhesion evaluation increases rapidly. There is a tendency to decrease.
Therefore, in order to obtain comparatively good flowability evaluation and adhesion evaluation values, it is preferable that the difference of (T1−T2) exceeds 10 ° C., but is within a range of less than 100 ° C. Further, in order to obtain values of better flowability evaluation and adhesion evaluation, it is preferable to set the difference of (T1−T2) to a value within the range of 20 to 90 ° C.
In addition, the flowability evaluation (relative value) and the adhesion evaluation (relative value) of the decorative part are respectively 5 for ◎, 3 for ◯, 1 for △, and x for the evaluation criteria shown in Example 1. It is calculated as one point.

Moreover, the decoration part is formed from the three-dimensional crosslinked material of an ultraviolet curable composition, It is characterized by the above-mentioned. More specifically, the ultraviolet curable composition is configured by blending at least a urethane acrylate oligomer, a reactive vinyl monomer, and a photopolymerization initiator .
Here, the urethane acrylate oligomer is preferably a bifunctional polyester urethane (meth) acrylate having a finger ring urethane or an aliphatic urethane structure in the skeleton.
This is because moderate strength and flexibility can be imparted by using a polyester-based urethane (meth) acrylate oligomer. Further, by using bifunctional polyester-based urethane (meth) acrylate as a main component, it becomes easy to adjust the softening temperature (T2) of the decorative portion, and in relation to the softening temperature (T1) of the base material, it is predetermined. This is because it is easy to limit the range. Conversely, when a trifunctional polyester-based urethane (meth) acrylate is used as a main component, the crosslinking density increases, and the elongation required at the time of molding may be insufficient.
Moreover, it is preferable to make the number average molecular weight (measured using GPC) of a urethane acrylate oligomer into the value of 1,000 or more.
The reason for this is that when the number average molecular weight of the urethane acrylate oligomer is less than 1,000, the adhesion of the decorating part to the substrate may be reduced, or the flowability of the decorating part may be reduced. Because. However, when the number average molecular weight of the urethane acrylate oligomer is excessively large, the handleability may be lowered, or the curing reaction by ultraviolet rays may be lowered.
Therefore, the number average molecular weight of the urethane acrylate oligomer is more preferably a value within the range of 2,000 to 30,000, and even more preferably a value within the range of 3,000 to 10,000.
The bifunctional polyester urethane acrylate used in Example 1 and the like specifically has an average molecular weight of 3,000, and the isocyanate as a starting material is isophorone diisocyanate (IPDI). The polyol as is the content of polyester polyol.

As the reactive vinyl monomer, it is preferable to use a linear or cyclic single-capacity (meth) acrylate. This is because the addition of the acrylate monomer makes it easy to adjust the softening temperature (T2) of the decorative portion without lowering the elongation.
The monofunctional acrylate monomer (A) used in Example 1 and the like is specifically vinyl caprolactam, and the monofunctional acrylate monomer (B) is specifically phenoxyethyl acrylate and bifunctional acrylate monomer. (C) is specifically tripropylene glycol diacrylate.
The addition amount of the reactive vinyl monomer is preferably determined in consideration of the addition amount of the urethane acrylate oligomer. Specifically, the weight ratio of the urethane acrylate oligomer and the reactive vinyl monomer is 1: 1 to 1. : A value within the range of 3 is preferable.
The reason for this is that when the weight ratio is less than 1: 1, the curing reaction due to ultraviolet rays may be remarkably reduced, or the softening temperature (T2) value of the decorative portion to be obtained may be excessively reduced. Because. On the other hand, if the weight ratio exceeds 1: 3, it may be difficult to control the curing reaction by ultraviolet light, or the softening temperature (T2) of the resulting decorative part may be excessively high. is there.
In addition, in blending the ultraviolet curable composition, it is preferable that a solvent is not added and a so-called solventless ultraviolet curable ink is used.
This is because the manufacturing apparatus can be reduced in size and the problem of environmental pollution is reduced as compared with the solvent-containing ultraviolet curable ink.

In addition, for the purpose of coloring or decorating the decorative portion, it is also preferable to add a pigment, an extender pigment, various metal powders or fluorescent pigments for imparting various decorating properties and functionality, and further a luminous pigment.
In particular, by adding a predetermined amount of titanium oxide in the ultraviolet curable composition, as shown in FIG. 3, while maintaining a predetermined value of elongation at break, in the decorative sheet for inserts during insert molding It is possible to further reduce the flow and peeling of the decorative portion. Moreover, in a decoration part, concealment property and decoration property can be improved by including a predetermined amount of titanium oxide.
Further, the ultraviolet curable composition shown in FIG. 3 is in accordance with the composition of Example 1 described later, and is an ultraviolet curable composition formulated by changing the amount of titanium oxide added thereto. Even when the amount of addition is 30% by weight, the elongation at break shows a high value of 180% or more. That is, by changing the amount of titanium oxide added and configuring the decorating part, the flow and peeling of the decorating part in the insert decorating sheet during insert molding can be easily controlled.
Titanium oxide is usually hydrophilic, and if added as it is, the water resistance of the decorative part may be lowered. Therefore, it is more preferable to use hydrophobic titanium oxide obtained by surface-treating titanium oxide with a silane coupling agent or a titanium coupling agent.
Furthermore, regarding the configuration of the decoration part, as shown in FIG. 1C, it is preferable that the surface of the base material 10 further includes a second decoration part 12 ′.

(3) Binder layer Moreover, in comprising the resin molded product of this invention, while including a binder layer between the surface of a resin molded product, and a decoration part, the softening temperature of the said binder layer is T3 (degreeC). It is preferable that the relationship of T2 + 100>T3> T2 + 10 is satisfied.
That is, it is preferable to set the softening temperature (T3) of the binder layer to be slightly higher than the softening temperature (T2) of the decorative portion, and to be approximately the same as the softening temperature (T1) of the base material. The reason for this is that it is possible to prevent the flow of the decorative portion even in the injection of the high-temperature molten resin at the time of molding. Moreover, it is because the adhesiveness between a decoration part and a resin molded product can be improved with this binder layer. Furthermore, since the predetermined decorative portion is formed between the base material having the predetermined softening temperature and the binder layer, the flow and peeling of the decorative portion in the insert decorative sheet at the time of insert molding This is because it is possible to further reduce the above.

Here, the binder layer includes a mixture of a polyester resin and a polyurethane resin (weight ratio: 20:80 to 80:20) .
The reason for this is that by providing such a binder layer, adhesion between the decorative portion made of the ultraviolet curable ink cured film and the molding resin is imparted.
The polyester resin (A) used in Example 1 and the like specifically has an average molecular weight of 18,000 and a glass transition temperature of 84 ° C. The polyester resin (B) specifically has an average molecular weight of 15,000 and a glass transition temperature of 26 ° C., and the polyurethane resin (C) specifically has a polyester urethane resin having an average molecular weight of 40,000. The glass transition temperature is 83 ° C., and the polyurethane resin (D) is specifically a polyester urethane resin having an average molecular weight of 18,000, and the glass transition temperature is 34 ° C.

The binder layer contains silica particles, particularly hydrophobic silica particles, and the addition amount of the silica particles is set to a value in the range of 5 to 50 parts by weight with respect to 100 parts by weight of the main component of the binder layer. Is preferred.
The reason for this is that the heat resistance of the binder layer is improved by adding such an added amount of silica particles to the binder layer, for example, when a high-temperature molding resin of 200 ° C. to 300 ° C. is injected. This is because the flow of the decorative portion can be reduced. Moreover, it is because water resistance can be remarkably improved by adding a predetermined amount of hydrophobic silica to the binder layer as compared with the case where untreated (hydrophilic) silica particles are added. Furthermore, by containing hydrophobic silica particles in this way, fine irregularities can be formed on the surface, so that the adhesion with the molding resin injected during injection molding can be improved.
Silica particles are usually hydrophilic as they are, but can be made into hydrophobic silica particles by introducing a methyl group around them or treating them with a coupling agent.

Here, with reference to FIG. 4, the relationship between the addition amount of hydrophobic silica particles and the flowability and adhesion of the decorative portion will be described in detail. That is, the horizontal axis of FIG. 4 shows the amount (parts by weight) of hydrophobic silica particles added to 100 parts by weight of the main component of the binder layer, and the left vertical axis shows the flowability evaluation of the decorative part. (Relative value) is shown, and on the right vertical axis, the adhesion evaluation (relative value) of the decorative portion is shown. And as the solid line shows, the tendency for the value of fluidity | liquidity evaluation to become favorable is seen, so that the addition amount of hydrophobic silica particle increases. Moreover, as the dotted line shows, the greater the amount of hydrophobic silica particles added, the better the value of adhesion evaluation, but when it becomes excessively large, for example, 50 parts by weight or more, the value of flowability evaluation becomes There is a tendency to decrease rapidly.
Therefore, in order to obtain relatively good flowability evaluation and adhesion evaluation values, the amount of hydrophobic silica particles added should be within the range of 10 to 45 parts by weight with respect to the total amount. In order to obtain a better flowability evaluation and adhesion evaluation value, it is preferable to set the value within the range of 15 to 40 parts by weight.
In addition, the flowability evaluation (relative value) and the adhesion evaluation (relative value) of the decorative part are respectively 5 for ◎, 3 for ◯, 1 for △, and x for the evaluation criteria shown in Example 1. It is calculated as one point.

2. Plastic molded product
Moreover, ABS resin or polycarbonate resin is mentioned as a main component of a resin molded product.
The reason for this is that by making such a resin molded product, the adhesion between the decorative portion and the resin molded product can be enhanced. Furthermore, the moldability of the resin molded product can be further improved.

3. Production method (1) Creation of decorative sheet for insert The formation of the decorative portion made of ultraviolet curable ink is preferably performed by a screen printing method because it can be printed easily and accurately. For example, it is preferable to print using a 300-mesh screen, and to cure by ultraviolet exposure to form a decorative portion having a thickness of 10 to 20 μm.

Moreover, when forming the decoration part of another color, or when making thickness thicker, it is also preferable to set it as a multilayer structure.
That is, after printing a predetermined pattern made of a solvent-free ultraviolet curable ink on a substrate using a screen printing device, using a UV curing device, for example, a lamp height of 100 mm, a conveyor speed of 8 m / min, exposure It is preferable that the first decorative layer is formed by irradiating ultraviolet rays under a condition of an amount of 300 mJ / cm ² to cure the solventless ultraviolet curable ink. Next, on the obtained first decorative layer, under the same conditions, a second decorative layer having an average thickness of 10 μm is formed, and a decorative portion having an overlapping structure having a total average thickness of 20 μm; can do.
However, the method for forming the decorative portion is not limited to the screen printing method, and other known printing techniques such as a gravure printing method can also be used.
Moreover, when the decorating sheet for inserts contains a binder layer, it is preferable to form the said binder layer on a decorating part using a screen printing method. More specifically, it is preferable to screen-print a binder resin solution using a 200-mesh screen and dry the solvent, and then form a binder layer having a thickness of 6 to 10 μm.
In addition, regarding the solvent removal (it may include hardening) of a binder layer, it is preferable to heat-process on condition of 80 degreeC and 1 hour as an example using a dryer.

(2) Creation of resin molded article Next, it is preferable to preform the obtained decorative sheet for insert into a predetermined shape using a vacuum forming apparatus. This is because the surface of the resin molded product can be accurately followed in a mold such as an injection molding apparatus.
Next, in a state where the insert decorative sheet is inserted into a mold such as an injection molding apparatus, a molding resin, for example, an ABS resin is injection-molded from the outside into the mold to create a resin molded product. Is preferred.
Therefore, after injection molding, the resin molded product having a decorative sheet for insert on the surface can be obtained by taking it out from the mold and cooling it to room temperature.

[Example 1]
1. Preparation of decorative sheet for insert As shown in Table 1, 100 parts by weight of bifunctional urethane acrylate oligomer, 50 parts by weight of monofunctional acrylate monomer (A), 50 parts by weight of monofunctional acrylate monomer (B), and titanium oxide 100 parts by weight, 23 parts by weight of a silicone-based additive, and 23 parts by weight of a photopolymerization initiator were blended, and a solvent-free UV curable ink (type 1, softening temperature (T2) at curing: 55 ° C.) Prepared.
Next, using a screen printing apparatus (300 mesh screen), on a bi-hole (manufactured by Bayer, softening temperature (T1): 110 ° C., abbreviated as PC in Table 3) which is a polycarbonate film having a thickness of 125 μm. A predetermined pattern made of a solventless UV curable ink was printed. Then, using a conveyor type UV curing device (one metal halide lamp with a 120 W / cm heat ray cut filter), UV irradiation was performed under the conditions of a lamp height of 100 mm, a conveyor speed of 8 m / min, and an exposure amount of 300 mJ / cm ^2. Then, the solventless ultraviolet curable ink was cured to form a first decorative layer having an average thickness of 10 μm.
Next, on the obtained first decorative layer, under the same conditions, a second decorative layer having an average thickness of 10 μm is formed, and a decorative portion having an overlapping structure having a total average thickness of 20 μm; did.
Finally, as shown in Table 2, a solvent comprising a polyester resin (A), a polyurethane resin (C), hydrophobic silica particles, and an acrylic additive on the decorative portion of the overlapping structure. A mold binder resin coating solution was prepared, and then a 10 μm thick binder layer (type 1, softening temperature (T3): 110 ° C.) was formed as a decorative sheet for inserts.
The softening temperature (T1) of the polycarbonate film, the softening temperature (T2) of the decorative part, and the softening temperature (T3) of the binder layer are JIS K 7169-1991 “softening by mechanical analysis of thermoplastic film and sheet, respectively. Measured based on “temperature test method”.

2. Production of Resin Molded Product The obtained decorative sheet for insert was preformed into a predetermined shape by a vacuum molding device and then inserted into a mold of an injection molding device. In that state, the ABS resin was injection molded, taken out from the mold, and cooled to room temperature to obtain a resin molded product provided with a decorative sheet for insert on the surface.

3. Evaluation of resin molded product (1) Flowability of decorative part In the obtained resin molded product, a predetermined pattern of the decorative part was visually observed, and the flowability of the decorative part was evaluated according to the following criteria.
(Double-circle): The flow of a decoration part is not observed at all.
○: Almost no flow in the decorative part is observed.
(Triangle | delta): The flow of a decoration part is observed a little.
X: The flow of a remarkable decoration part is observed.

(2) Damage of decorative part In the obtained resin molded product, the appearance of the decorative part having an elongation of 180% to 200% is visually observed, and the damage (crack or crack) of the decorative part is as follows. Confirmed according to the criteria.
A: No cracks or cracks are observed.
○: Almost no cracks or cracks are observed.
Δ: Some cracks and cracks are observed.
X: A remarkable crack and a crack are observed.

(3) Adhesiveness of the decorative part A cut-out is cut with a cutter knife on the surface of the resin molded product, the decorative part with the cut is sandwiched and lifted with pliers, and the decorative part is in accordance with the following criteria Evaluation of adhesion was performed.
(Double-circle): A decoration part fractures | ruptures and peeling does not spread from a predetermined location.
○: The decorative portion is partially broken, and the peeling hardly spreads from the predetermined location.
(Triangle | delta): Separation partly spreads along the cut | interruption of a decoration part.
X: Peeling spreads along the cut line of the decorative part, and remarkable peeling of the decorative part is observed.

(4) Water resistance of decoration part The obtained resin molded product was immersed in 40 degreeC warm water for 1 week, and the water resistance evaluation of the decoration part was performed according to the following references | standards.
A: No change in appearance is observed.
○: Almost no change in appearance is observed.
Δ: A slight change in appearance is observed.
X: A remarkable change in appearance is observed.

[Example 2]
In Example 2, instead of the solventless UV curable ink (type 1) used in Example 1, as shown in Table 1, the amount of the monofunctional acrylate monomer (A) added was 67 parts by weight. A decorative sheet for inserts was prepared in the same manner as in Example 1 except that solvent-type ultraviolet curable ink (type 2, softening temperature: 40 ° C.) was used.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Example 3]
In Example 3, instead of the solventless UV curable ink (type 1) used in Example 1, as shown in Table 1, the addition amount of the bifunctional urethane acrylate oligomer was 100 parts by weight, and the monofunctional acrylate monomer Except for using solvent-free UV curable ink (type 3, softening temperature: 80 ° C.) with 29 parts by weight of (A) and 43 parts by weight of monofunctional acrylate monomer (B). A decorative sheet for insert was prepared in the same manner as in Example 1.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Example 4]
In Example 4, instead of the binder resin (Type 1) used in Example 1, the binder resin shown in Table 2 (Type 2, 30 parts by weight of hydrophobic silica, 15 parts by weight with respect to the main component) is used. A decorative sheet for insert was prepared in the same manner as in Example 1 except that.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Example 5]
In Example 5, instead of the binder resin (Type 1) used in Example 1, the binder resin shown in Table 2 (Type 3, 40 parts by weight of untreated silica, 20 parts by weight with respect to the main component) is used. A decorative sheet for insert was prepared in the same manner as in Example 1 except that.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Comparative Example 1]
In Comparative Example 1, instead of the solventless UV curable ink (type 1, softening temperature (T1): 130 ° C.) used in Example 1, the amount of trifunctional urethane acrylate oligomer added as shown in Table 1 Solvent-free UV curable ink (type 4, softening temperature (T1), wherein 100 parts by weight of the monomer, 50 parts by weight of the monofunctional acrylate monomer (A) and 50 parts by weight of the monofunctional acrylate monomer (C) ): 130 ° C.), an insert decorative sheet was prepared in the same manner as in Example 1.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Comparative Example 2]
In Comparative Example 2, instead of the solventless ultraviolet curable ink (type 1) used in Example 1, as shown in Table 1, type 5 solventless ultraviolet curable ink (softening temperature: 113 ° C.) was used. A decorative sheet for insert was prepared in the same manner as in Example 1 except that it was used.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Comparative Example 3]
In Comparative Example 3, instead of the solventless ultraviolet curable ink (type 1) used in Example 1, as shown in Table 1, type 5 solventless ultraviolet curable ink (softening temperature: 113 ° C.) was used. While using, the decorative sheet for inserts was created similarly to Example 1 except having used the binder resin (type 2) shown in Table 1 instead of the binder resin (type 1) used in Example 1. FIG.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Comparative Example 4]
In Comparative Example 4, instead of the solventless ultraviolet curable ink (type 1) used in Example 1, as shown in Table 1, type 5 solventless ultraviolet curable ink (softening temperature: 113 ° C.) was used. While using, the decorative sheet for inserts was created similarly to Example 1 except having used the binder resin (type 3) shown in Table 1 instead of the binder resin (type 1) used in Example 1. FIG.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Comparative Example 5]
In Comparative Example 5, instead of the solventless ultraviolet curable ink (type 1) used in Example 1, as shown in Table 1, type 5 solventless ultraviolet curable ink (softening temperature: 113 ° C.) was used. While using, the decorative sheet for inserts was created similarly to Example 1 except having used the binder resin (type 4) shown in Table 1 instead of the binder resin (type 1) used in Example 1. FIG.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Comparative Example 6]
In Comparative Example 6, instead of the solventless ultraviolet curable ink (type 1) used in Example 1, as shown in Table 1, type 5 solventless ultraviolet curable ink (softening temperature: 113 ° C.) was used. While using, the decorative sheet for inserts was created similarly to Example 1 except having used the binder resin (type 5) shown in Table 1 instead of the binder resin (type 1) used in Example 1. FIG.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

[Comparative Example 7]
In Comparative Example 7, instead of the solventless ultraviolet curable ink (type 1) used in Example 1, as shown in Table 1, type 5 solventless ultraviolet curable ink (softening temperature: 113 ° C.) was used. While using, the decorative sheet for inserts was created similarly to Example 1 except having used the binder resin (type 6) shown in Table 1 instead of the binder resin (type 1) used in Example 1. FIG.
Next, resin molded products were prepared and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3.

According to the resin molded product having the decorative sheet for inserts on the surface thereof, the softening temperature (T1) of the base material constituting the decorative sheet for inserts and the softening temperature (T2) of the decorative part are predetermined. By satisfying the relationship, the flow of the decorative part in the decorative sheet for inserts during insert molding that requires high elongation, even when the amount of pigment added is increased or a multilayer structure is used. And peeling can be reduced.
Therefore, it is expected to be applied to obtain a resin molded product having excellent decorativeness by vacuum molding or insert-in-mold molding.
In addition, the decorative part is formed from a three-dimensional cross-linked product of an ultraviolet curable composition, which reduces the burden on the environment, shortens the production line that is long, and increases production efficiency. Is expected to do.
Furthermore, since the water resistance can be improved by adding a predetermined amount of hydrophobic silica particles to the binder layer of the decorative sheet for inserts, it is expected that the resin molded product is used as a product around water.

(A) is sectional drawing which shows typically the example of the decoration sheet for inserts which does not contain a binder layer , (b)-(c) is the aspect example of the decoration sheet for inserts containing a binder layer. It is sectional drawing shown typically. It is a figure provided in order to demonstrate the relationship (T1-T2) of the softening temperature (T1) of a base material, and the softening temperature (T2) of a decoration part, and the flowability and adhesiveness of a decoration part. It is a figure provided in order to demonstrate the relationship between the addition amount of the titanium oxide in a decorating part, and the breaking elongation of a decorating part. It is a figure provided in order to demonstrate the relationship between the addition amount of the hydrophobic silica in a binder layer, the flow property of a decorating part, and adhesiveness. It is a figure provided in order to demonstrate the resin molded product provided with the conventional decorative sheet for inserts on the surface. It is a figure provided in order to demonstrate the conventional decorating sheet for inserts.

Explanation of symbols

10: Base material 12: Decorating part (first decorating part)
12 ': 2nd decoration part 13: Binder layers 14, 14', 14 ": Decoration sheet for insert 16: Resin molded product

Claims (4)

It is a resin molded product provided with a decorative sheet for insert including a base material and a decorative portion on the surface,
A binder layer is included between the surface of the resin molded product and the decorative portion,
When the softening temperature of the base material is T1 (° C), the softening temperature of the decorative portion is T2 (° C), and the softening temperature of the binder layer is T3 (° C),
The softening temperature (T1) of the base material is set to a value within a range of 95 to 140 ° C.,
The softening temperature (T2) of the decorative part is a value within the range of 35 to 100 ° C.,
While satisfying the relationship of T2 + 100>T1> T2 + 10,
T1-T2 is set to a value within a range of 20 to 90 ° C.,
And satisfies the relationship of T2 + 100>T3> T2 + 10,
Furthermore, the decorative part is formed from a three-dimensional cross-linked product of an ultraviolet curable composition containing at least a urethane acrylate oligomer, a reactive vinyl monomer, and a photopolymerization initiator ,
The main component of the resin molded product is ABS resin or polycarbonate resin,
A resin molded product , wherein the binder layer contains a mixture of a polyester resin and a polyurethane resin .   The decorative portion includes a urethane acrylate oligomer having a number average molecular weight of 1,000 or more, a reactive vinyl monomer, and a photopolymerization initiator, and a weight of the urethane acrylate oligomer and the reactive vinyl monomer. The resin molded article according to claim 1, comprising a three-dimensional crosslinked product of an ultraviolet curable composition having a ratio in a range of 1: 1 to 1: 3.   The ultraviolet curable composition contains titanium oxide, and the addition amount of the titanium oxide is set to a value within a range of 1 to 40 parts by weight with respect to 100 parts by weight of the urethane acrylate oligomer. Item 3. A resin molded article according to Item 1 or 2.   The binder layer contains hydrophobic silica particles, and the addition amount of the hydrophobic silica particles is set to a value in the range of 5 to 50 parts by weight with respect to 100 parts by weight of the main component of the binder layer. The resin molded product according to any one of claims 1 to 3.

Images