A mold tool for plastic injection and a method of using the mold tool for manufacturing a vehicle trim element

Abstract

The present invention relates to a mold tool (for plastic injection molding process comprising a mobile core and a base core of which at least one core configured to move and abut the other, a mold cavity configured to be provided inbetween the mobile core and base core, at least one injection channel for injecting plastic material into the mold cavity.

Description

A MOLD TOOL FOR PLASTIC INJECTION AND A METHOD OF USING THE MOLD TOOL FOR MANUFACTURING A VEHICLE TRIM ELEMENTFIELD OF THE INVENTION

[0001] The application relates to a mold tool for plastic injection and a method for fabricating a vehicle interior / exterior trim element comprising a thin glass sheet. In addition, the application relates to a vehicle trim element.BACKGROUND OF THE INVENTION

[0002] The invention is primarily intended to be used in production of automotive glazing but not limited to. It is known to use glass panels in vehicle interiors, for example as a mirror or as instrument glass. Glass is known for its high-quality optical and haptic appearance. Further, displays are commonly installed in vehicle interiors to provide a driver or a passenger with information. In some applications, a display may be arranged behind an optically transparent glass panel, e.g., to protect the display from food or beverage spills or from scratches.

[0003] However, glass panel today may be not only used as an optically transparent glass panel, e.g., to protect the display but also as a glass interior trim element into a motor vehicle or a center console or a glass exterior trim element also known as glass applique.

[0004] Interior or exterior trim vehicle refers to the items that can be added to the interior or exterior of an automobile or a motor vehicle in general (car, bus, train...) to increase its appeal. There are several types of vehicle trim. Some are used to protect some part of the interior vehicle from unwanted damage that can be caused by the passenger, while others are simply for aesthetics.

[0005] Moreover, today car manufacturers tend to use more and more glass inside and / or outside the vehicle and particularly as cover glass of the dashboard and this particularly to have display behind the cover as for example analog-digital hybrid touch panel apparatus and a recognition method thereof.

[0006] Also, not only for aesthetic point of view but particularly for adding more and more functionalities on some part on interior and / or exterior of vehicle, particularly on trim elements, car manufacturers are looking for replacing plastic, wood... trim element by glass which are more resistant to scratches and because more functionalities may be added on them.

[0007] Generally, the top part of the center console is made of plastics, polycarbonate elements (plastics materials are used as a cover to the whole console system). This solution is often aesthetic but does not allow adding directly some functions on the center console as such "touch screen functionalities" with good efficiency.... Furthermore, the disadvantages of having a plastic molded center console are the following: since there is no touch functionality permitted with plastics, an overload of useless buttons must be installed on the console. At the end of the day, the multitude of buttons confuses the driver (safety aspect). Additionally, because there is no seamless effect, it is more difficult to clean the center console as the dust is incrusted around the buttons, etc.... (hygiene downside). The plastic material used to cover the center console is hardly recyclable whereas glass is endlessly recyclable (environmental issue). The molding process of the plastic parts results in plastics ending up as wastes (recyclable plastics prices are not competitive with newer plastics prices, therefore there is currently no viable alternative to address this environmental concern). In general, plastics material used a glass cover are not highly resistant to UV and the transparent tint turns into yellow with time (deterioration of the design). Additionally, in order to present a similar stiffness than glass, a cover made of plastics will be heavier than one made of glass. Therefore, plastics material solutions are not optimal for this car part in order to lighten the car. As technology cycles go faster and faster, a glass center console would allow flexibility for IT upgrades to be made and allows for seamless connectivity with nomadic devices. By having a glass center console, it would allow to reconcile the many different software that are typically supported by the car into one Operating System located and commanded from the same place. Additionally, in contrast to most of the materials currently used as parts of the center console, glass can support the use of ambient light (improving the comfort / convenience of the passengers). Furthermore, the passenger does not want to see anymore plastic in his interior's car similarly to his house or his office interior's.

[0008] The current interior decorative or functional parts are mainly made of decorative plastics. Therefore, fixation elements can be directly integrated to these parts. However, the plastic parts have the disadvantage to be damaged when being touched and over the lifetime of the vehicle, due to their low resistance to abrasion. Furthermore, the effect of having plastic in the car for the user interface (visible decoration or functional panel) is not optimal for the high-end finishing, plastics being considered as a low-quality material. Another criteria is the feeling when touching plastic, user feels to touch a weak material, and the sensation atfingertips is hot and soft, giving the impression of a low end material. The current solutions therefore do not need to integrate specific intermediate parts for assembly.

[0009] Thus, glass trim elements or a glass console are preferred to have a better aesthetic and allow to increase the appeal of the vehicle. Glass trim elements are more difficult to fix to the interior's vehicle because they must comply with safety rules.

[0010] Glass trim elements are preferably curved glass panels. Curved glass panels may be formed by first heating a glass panel to a temperature above the softening point of the glass panel. Subsequently the glass panel may be deformed by either actively bending the glass panel using a bending device or by letting the glass bend due to its own weight. Alternatively, cold forming processes may be used when bending glass panels. These processes are known to consume less energy and time. In a cold forming process, a glass panel is typically bent at room temperature on a curved frame. After bending the glass panel, e.g., when a curvature of the glass panel corresponds to a curvature of the curved frame, the glass panel is strained and tends to gradually take back its initial shape. Therefore, the bent glass panel typically needs to be mechanically fixed to the curved frame after bending to retain the curvature of the glass panel.

[0011] A multitude of flexible, inorganic glass films are layered with an interposition of an adhesive layer between the glass films. In a molding tool the glass layers are compressed and held at a temperature below a glass transition temperature until the adhesive is cured such that a self-supporting molded glass part is formed.

[0012] When a glass panel comprising a functional element such as a display is bent, problems may occur relating to the strain exerted on a bonding interface between the functional element and the glass panel or on the functional element itself by the bending process. Consequently, a detachment or breakage of the functional element may occur. Similar problems may occur when a glass panel comprises a hole for receiving a functional element such as a display, an air vent, or a rotary knob. The panel is weakened due to the hole, and the stress in the panel around the hole may exceed critical values with the consequence of unwanted deformation or even breakage.

[0013] Today, double sided tape is mainly used in order to fix thin glass on a support called carrier plate. This carrier plate is then used to make the assembly of the module created in the vehicle. This allows a full surface connection between the glass and generally the plastic part used as carrier plate which is highly recommended for passing homologation tests. Thissolution leads to an acceptable bonding quality. However, the process used to make the assembly is difficult to implement industrially. Indeed, this kind of tape bonding has the disadvantage of having an immediate gluing of the glass on the tape as soon as the glass is touching this tape. It means that it is mandatory to fix the glass in the correct position at the early stage of the assembly process i.e. when the glass has to be fixed on the carrier plate.

[0014] Thus, overmolding soft plastic material inbetween the thin glass sheet and the carrier plate is realized to solve the above problems, such a method is disclosed in WO2020178383. However, even with injection of soft material inbetween the thin glass sheet and the carrier plate to bond / fix the thin glass sheet to the carrier plate, there are several issues which can be preventing the use of overmolding methods.

[0015] Basically, the yield of overmolding method cannot be guaranteed and the thin glass sheet may be broken inside the mold tool during the injection or even after injection due to stresses built up inside.

[0016] Moreover, the uneven stress distribution on the thin glass sheet inside the cavity mold due to the nature of the injection process may cause deformation on the end product that the yield is reduced even more.

[0017] Additionally, due to the high injection pressures, the holders / fixers that used to keep the thin glass sheet in fixed position during the injection process may leave a mark on the thin glass sheet surface that may affect the aesthetic appearance of the end product. Trace marks on the glass sheet surfaces are a very well-known issue in overmolding process.

[0018] On top of the marks left on the thin glass sheet surface, the holders / fixers of the current technology may not allow to produce trim elements with complex curvatures such as highly curved trim element or biaxially curved trim elements.

[0019] Furthermore, the current methods even with the highest level of control and precision, may not have a solution to the spring-back effect due to the nature of the injection process. Since the temperature of the injected material is higher than the thin glass sheet or the carrier plate, final shape of the end product may not comply with the requirements of the car manufacturer. The defects in the final shape of the end product needs to be compensated by the extra tolerances during the installation process.

[0020] W02020178383 describes a method for manufacturing a trim element for a vehicle wherein a thin glass panel is cold bended and soft material is injected inbetween a carrierplate and the thin glass panel. Vacuum cups are used to maintain the glass panel in its final shape and such vacuum cups leave marks on the final product.

[0021] CNl08237659 describes a moulding tool for forming and back-injecting a flexible sheet such as glass sheets. The moulding tool comprises retractable pins, which are preferably mounted in the half of the mould comprising the openings or recesses for injecting the melt. As the retractable pins are facing the injection cavity, there may be a flow into the bores while the injection process which requires constant maintenance. Moreover, since there is a contact with the flexible sheet, there may be marks on the sheet afterwards.

[0022] US11192341 describes a lamination method of a thin glass sheet having a thickness less than 1 mm with a thicker glass sheet by at least one thermoplastic film.

[0023] It is known from CN110520293 that a vehicle interior trim element comprising thin glass sheet wherein the thin glass is cold bended with the help of vacuum.

[0024] None of the prior art above suggest a solution to all the issues mentioned above at once during the manufacture / assembly step of the vehicle trim element.SUMMARY OF THE INVENTION

[0025] The goal of the present invention is to provide a mold tool for being used in plastic injection process to support cold bending of thin glass sheets and also to eliminate the aforementioned problems.

[0026] 0ne aspect of the present invention relates to a mold tool provided that the breakage of the thin glass sheet is minimized, or even eliminated. Therefore, the yield of the production is dramatically increased.

[0027] Another aspect of the present invention relates to the uniform distribution of the pressure over the thin glass sheet and in another aspect of the present invention relates to elimination of the marking of the holders / fixers traces on the thin glass sheet, thus therefore, the manufacturing defects are decreased and the aesthetic and also functionality of the end product is increased.

[0028] 0ne further aspect of the present invention relates to a mold tool that allows cold bending of thin glass sheet into complex curvatures with high precision and in another aspect of the present invention relates to a vehicle trim element comprising a thin glass sheet with precisely curved into desired curvature values and especially for biaxial curving / bending.

[0029] The mold tool of the present invention comprises plurality of openings preferably in the form of holes on the surface of the core plates of the mold tool. The said openings are used to create suction, especially uniform suction for the piece that will be overmolded. Therefore, full surface of the piece that will be overmolded may be supported. Plastic injection mold tools are very well known, in a simplified manner two core plates abut each other, and a cavity is formed inbetween and then the plastic material is injected into the cavity and the further details of the mechanism of the tool will not be described here in detail.

[0030] In the case of the piece that will be overmolded being a thin glass sheet, pre-shaping of the thin glass sheet is realized by the suction provided through the openings. Due to the selection of the parameters of the openings as small enough not to leave marking traces and big enough to enable sufficient suction, cold bending of thin glass sheets can be realized inside the mold tool with the ability of achieving high curvature values without glass breakage and trace markings of the vacuum elements.

[0031] Especially during the injection process, it is important to have a full surface support forthe thin glass sheet in orderto prevent breakage. In addition to the prevention of breakage, it is also very important to keep the thin glass sheet in the desired shape / curvature during the injection. The openings of the present invention provides the required full surface support to the thin glass sheet that substantially high curved structures can be manufactured and the glass breakage is substantially eliminated.

[0032] The present invention also provides a method for cold bending of a thin glass sheet in the mold tool provided with the openings for suction. With the proposed method, such cold bending can be realized inside the mold tool and therefore, two different operations are realized in only one step. However, thin glass sheet may also be bended at a bending station and then transferred to the mold tool as pretensioned and the injection is realized in the mold tool.

[0033] In another embodiment of the present invention, the core plate having the openings comprises two blocks of which one block serves as the base and connected to the suction means. The other block, namely the top block comprises the corresponding mold shape as well as the openings specialized to the corresponding mold shape. With this embodiment, parameters of the openings such as diameter, distance between adjacent openings and the pattern or the density of the openings can be determined according to the desired mold shape.

[0034] Thereto re, having the two blocks of the core plate not only enables the numerous mold shapes but also ensures the robustness of the cold bending and the injection process since the parameters of the openings defined based on the desired shape / curve. For instance, the distance between the adjacent openings can be determined based on the inclination of the desired shape / curvature that may help reduction of the stress built up inside the thin glass sheet during bending and injection process, i.e., that may help to compensate the reaction forces inside the thin glass sheet during cold bending and / or injection process.

[0035] In a version of this embodiment, thanks to the multiple structure of the mold tool, variable suction can be achieved, mainly, different suction power can be applied to different areas of the thin glass sheet that also supports highly curved structures and also eliminate the possibility of breakage.

[0036] Moreover, in a further embodiment of the present invention, the parameters of the openings can be defined based on the thickness of the thin glass sheet. With such a mold tool, thin glass sheets up to 3mm thickness can be cold bent during plastic injection process, in the preferred embodiment the thickness of the glass sheet is selected less than or equal to 2.1 mm, more preferably lower than 1.5 mm depending on the curvature to be achieved.

[0037] The mold tool of the present invention, as can be seen from the different embodiments, provides countless number of variations that serves defect -free manufacturing and also provides extra benefits mentioned above.

[0038] In addition to all above, the mold tool of the present invention provides a significant amount of cost reduction in the production of a vehicle trim element by decreasing number of operation steps.BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The invention will now be described further, by way of examples, with reference to the accompanying drawings, wherein like reference numerals refer to like elements in the various figures. These examples are provided by way of illustration and not of limitation. The drawings are a schematic representation and not true to scale. The drawings do not restrict the invention in any way. More advantages will be explained with examples. A better understanding of the present invention will be added upon reference to the following description in conjunction with the accompanying drawings.

[0040] Fig.1 is a schematic view of a mold tool according to one embodiment of the present invention.

[0041] Fig.2 is a perspective view of a core according to one embodiment of the present invention.

[0042] Fig.3 is a schematic view of the mold tool of the present invention during the injection process.

[0043] Fig.4 is a schematic view of the mold tool of the present invention after the injection process.

[0044] The elements illustrated in the figures are numbered as follows:100. Mold tool101. Mobile core102. Base core103. Mold cavity104. Injection channel105. Openings106. Top block107. Base block1. Thin glass sheet2. Carrier plate3. Trim elementDETAILED DESCRIPTION OF THE INVENTION

[0045] The present invention will be described with respect to particular embodiments and with reference to certain drawings, but the invention is not limited thereto but only by the claims.

[0046] While some embodiments described herein include some, but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0047] As used herein, spatial ordirectional terms, such as "inner", "outer", "above", "below", "top", "bottom", and the like, relate to the invention as it is shown in the drawing figures.However, it is to be understood that the invention can assume various alternative orientations and, accordingly, such terms are not to be considered as limiting. Further, all numbers expressing dimensions, physical characteristics, processing parameters, quantities of ingredients, reaction conditions, and the like, used in the specification and claims are to be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical values set forth in the following specification and claims are approximations that can vary depending upon the desired properties sought to be obtained by the present invention.

[0048] Moreover, all ranges disclosed herein are to be understood to be inclusive of the beginning and ending range values and to encompass any and all subranges subsumed therein. For example, a stated range of "1 to 10" should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more, e.g. 1 to 6.1, and ending with a maximum value of 10 or less, e.g., 5.5 to 10. Further, as used herein, the terms "deposited over" or "provided over" mean deposited or provided on but not necessarily in surface contact with. For example, a coating "deposited over" a substrate does not preclude the presence of one or more other coating films of the same or different composition located between the deposited coating and the substrate.

[0049] Where the term "comprising" is used in the present description and claims, it does not exclude other elements or steps. Where an indefinite or definite article is used when referring to a singular noun e.g. "a" or "an", "the", this includes a plural of that noun unless something else is specifically stated. In this document, "configured to (or set to)" may be interchangeably used in hardware and software with, for example, "appropriate to", "having a capability to", "changed to", "made to", "capable of", or "designed to" according to a situation. In any situation, an expression "device configured to do" may mean that the device "can do" together with another device or component.

[0050] Furthermore, the terms first, second and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequence, either temporally, spatially, in ranking or in any other manner. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein. When it is described that a constituentelement (e.g., a first constituent element) is "(functionally or communicatively) coupled to" or is "connected to" another constituent element (e.g., a second constituent element), it should be understood that the constituent element may be directly connected to the another constituent element or may be connected to the another constituent element through another constituent element (e.g., a third constituent element).

[0051] I n the following description, unless otherwise specified, expression "substantially" or "around" or "proximity" or "close to" preferably mean to within 10%, preferably to within 5% i.e., in this context the terms should be understood as in the range of ± 10%, even more ± 5%. Tolerance may be selected depending on the nature of the intended applications.

[0052] I n the following description, unless otherwise specified, expression "liquid adhesive", "optical coupling material", "optical resin", "optical coupling adhesive", "optical clear adhesive" and "liquid resin" are used interchangeably, further expression "functional film", "film", "electrically powered functional film" and "electrical functional film" are used interchangeably, further expression "flow", "fluidic flow", "liquid flow" and "liquid adhesive flow" are used interchangeably, further expression "primary part" and "hard component" are used interchangeably, further expression "secondary part" and "soft component" are used interchangeably, further expression "core plate" and "core" are used interchangeably, further expression "trim part" and "trim element" are used interchangeably, further expression "cavity" and "mold cavity" are used interchangeably, further expression "mold" and "mold tool" are used interchangeably.

[0053] A mold tool (100) for plastic injection molding process comprising a mobile core (101) and a base core (102) ofwhich at least one core (101, 102) configured to move and abut the other, a mold cavity (103) configured to be provided inbetween the mobile core (101) and base core (102), at least one injection channel (104) for injecting plastic material into the mold cavity (103). The mobile core (101) and the base core (102) may also be called as core plates since the shape of such is alike a plate. In the injection process, at least one of the cores (101, 102) moves and abuts the other to create the mold cavity (103) which is defined by the shape defined on the cores' surfaces, then the plastic material is injected through the injection channel (104). Moreover, two different plastic material may also be injected, which is also known as 2K process. Additionally, injection process may also serve to overmold plastic material onto another substance like thin glass sheet (1) in the preferred embodiments below.

[0054] According to the mold tool (100) of the present invention, the mold tool (100) comprises a plurality of openings (105) provided on a surface of at least one core (101, 102) facing the other, configured to provide suction. The openings (105) are manufactured on the surface of the core (101, 102) which is facing the other core (102, 101) with known machining techniques. The mold tool (100) further comprises a means for creating suction (not shown in the figures) through the openings (105). The said suction may be realized via various ways such as connecting a vacuum pump to the core or having venturi channels on the back side of the openings (105) and providing high pressure flow at the entry of the venturi channel.

[0055] The openings (105) preferably occupy substantially almost the whole surface of the core (101, 102) constituting the mold cavity (103). In the overmolding process, the substance is supported by the openings (105) and the substance is fixed on the core (101, 102). Therefore, the stability of the overmolding process is increased. Thanks to the openings (105) on the surface of at least one core (101, 102), the glass sheet (1) and / or the carrier plate (2) can be supported during the injection process.

[0056] In one embodiment of the present invention, diameter of the openings (105) is in the range of 0,5 to 10 mm. It has been found that the diameters of the openings (105) being the given range prevents trace marks left on the overmolded substance surface. Moreover, the given range also provides adequate suction power to support the substance. In the preferred version of this embodiment, the diameter of the openings (105) is in the range of 0.5 mm to 5 mm, and more preferably 1 mm to 2 mm and it has to be understood in the manufacturing tolerances.

[0057] In another embodiment of the present invention, the distance between adjacent openings (105) is in the range of 1 to 50 mm. In the preferred version of this embodiment, the distance between adjacent openings (105) is in the range of 1 to 10 mm. Before the injection process, the substance needs to be supported by or fixed onto the core (101, 102) surface and during the injection process, the substance needs to be immobile on the core (101, 102) surface for the sake of injection process. The substance is kept in place with the given range of the distance between adjacent openings (105), and therefore aforementioned problems are substantially eliminated.

[0058] In another embodiment of the present invention, the openings (105) facing inside the mold cavity (103). As the substance to be overmolded needs to be placed inside the mold cavity (103), the openings (105) are provided to be faced inside the mold cavity (103). Thisembodiment ensures that the suction is merely provided for the substance to be overmolded, and the energy requirements of powering suction is reduced.

[0059] In another embodiment of the present invention, the openings (105) are uniformly spread on the surface of the core (101, 102). Uniform distribution of the openings (105) enables uniform full surface support for the substance to be overmolded.

[0060] In another embodiment of the present invention, the openings (105) are nonuniformly spread on the surface of the core (101, 102), preferably with varying pattern. Within the different versions of this embodiment, the openings (105) may be provided with a varying pattern over the surface of the core (101, 102) and the varying pattern may be defined based on the parameters of the substance to be overmolded that the robustness of the cold bending and injection process is improved, further examples can be seen in the embodiments of the method below.

[0061] In another embodiment of the present invention, the core (101, 102) comprises a top block (106) wherein the openings (105) provided and a base block (107) wherein the top block (106) attached. In this embodiment, different top blocks (106) comprising openings (105) with different parameters may be utilized. Therefore, substances to be overmolded can be manufactured with different shapes and curvatures within the same mold tool (100).

[0062] In another embodiment of the present invention, as seen from the embodiments above, the mold tool (100) of the present invention may be used to cold bend thin glass sheets (1). The thin glass sheet (1) is the substance to be overmolded and it is placed inside the mold cavity (103) aligned with the openings (105). The thin glass sheet (1) is preformed / preshaped thanks to the openings (105) with suction. With the injection process, preshaped thin glass sheet (1) is permanently shaped by bonding with a carrier plate (2). In a version of this embodiment, the thin glass sheet (1) may be preformed / preshaped before it is provided inside the mold cavity (103) and the openings (105) may only support the preformed / preshaped thin glass sheet (1).

[0063] In another embodiment of the present invention, the suction level provided thru the openings (105) is configured to be selected proportional to the curvature value of the thin glass sheet (1). The more the glass sheet (1) needs to be curved, the more the suction level provided thru the openings (105). Therefore, the thin glass sheet (1) is supported well during the injection process.

[0064] In another embodiment of the present invention, the distance between adjacent openings (105) are configured to be selected inversely proportional to the thickness of the thin glass sheet (1) to be injected. Thicker glass sheets (1) require more support during the injection process, and as stated in the introduction, conventional systems / tools leave marks when the suction level is increased to a higher level than the predetermined level. In this embodiment, the distance between adjacent openings (105) are shortened, i.e., number of the openings (105) are increased for injection of thicker glass sheets (1) that the required support is provided without any marks on the glass sheet (1).

[0065] In another embodiment of the present invention, the distance between adjacent openings (105) are configured to be selected inversely proportional to the curvature value of the thin glass sheet (1) to be injected. Similar to the above embodiment, the more curvature of the glass sheet (1), the more support is needed. Therefore, in this embodiment, the distance between adjacent openings (105) are shortened, i.e., number of the openings (105) are increased for injection of highly curved glass sheets (1) that the required support is provided without any marks on the glass sheet (1). Furthermore, apart from providing adequate support for the glass sheet (1), the glass breakage is substantially reduced during the injection process as the surface of the glass sheet (1) is covered / supported in a large scale.

[0066] In another embodiment of the present invention, the distance between adjacent openings (105) are configured to be selected inversely proportional to the thickness and the curvature value of the thin glass sheet (1) to be injected. The combination of the embodiments above provide a competent support without any adverse effects like marks and / or breakage and / or etc. for any type of glass sheet (1) to be injected.

[0067] Therefore, the method disclosed in the present invention, comprises the steps of providing a carrier plate (2) onto the mold cavity (103) and providing a thin glass sheet (1) onto the mold cavity (103) with openings (105) to be preshaped by the suction provided through openings (105), and then cores (101, 102) abut each other to create the mold cavity (103), and then injecting of a plastic material inbetween the thin glass sheet (1) and the carrier plate (2). After cooling down, the cores (101, 102) move out and the final product has arisen as permanently shaped / curved thin glass sheet (1) as shown in Fig.4.

[0068] In another embodiment of the method of the present invention, the diameters of the openings (105) are defined proportionally with the thickness of the thin glass sheet (1).Therefore to be able to bend thicker glass sheets (1), the openings (105) are provided to have bigger diameters that the thicker glass sheets (1) are supported better.

[0069] In another embodiment of the method of the present invention, the suction level for the openings (105) are defined proportionally with the curvature value of the thin glass sheet (1). The mold tool (100) preferably comprises multiple suction circuits or a control unit (not shown) that controls the suction level for the openings (105), then the suction level, in other words, the vacuum level is defined based on the curvature of the thin glass sheet (1). For the high curvature values, the thin glass sheet (1) tends more to come back its flat position, therefore with this embodiment, more vacuum is provided where the thin glass sheet (1) has more curvature value.

[0070] In another embodiment of the method of the present invention, the distance between adjacent openings (105) selected inversely proportional to the thickness of the thin glass sheet (1). As the thinner glass sheets are easier to bend, a less dense openings (105) may help achieving the desired result. Therefore, manufacturing of both the mold tool (100) itself and the overmolded thin glass sheet (1) become more affordable.

[0071] In another embodiment of the method of the present invention, the distance between adjacent openings (105) selected inversely proportional to the curvature value of the thin glass sheet (1). Similar to the embodiment above, less curvature for the thin glass sheet (1) requires less openings (105) to help cost reduction.

[0072] In another embodiment of the present invention, a vehicle trim element (3) comprising the thin glass sheet (1) permanently shaped / curved and a carrier plate (2) made of plastic or metal, manufactured by the method of the invention using the mold tool (100) of the invention. The carrier plate (2) is provided onto a core (101, 102) and the thin glass sheet (1) is provided onto the other core (102, 101). The thin glass sheet is either cold bended in the mold tool (100) or just supported by the vacuum provided by the openings (105). Plastic material is injected inbetween the thin glass sheet (1) and the carrier plate (2) to produce the vehicle trim element (3).

[0073] In another embodiment of the present invention, the thin glass sheet (1) in the vehicle trim element (3) has a thickness less than 3 mm, preferably less than 1 mm.

[0074] In another embodiment of the present invention, the vehicle trim element (3) comprising a thin glass sheet (1) and a carrier plate (2), and a plastic material injected inbetween. In this embodiment the carrier plate (2) being hard plastic, injected plasticmaterial being soft plastic. In a preferred version of this embodiment, the hard plastic is chosen among PU, PP, PA, PC-PET, PC-ABS, PBT but not limited to and the soft plastic is chosen among TPE, TPV, PU but not limited to. Such materials are given as example, and material of injection may be any suitable thermoplastic or thermoset material. In a version of this embodiment, the carrier plate (2) is being metallic and plastic material is only injected inbetween the thin glass sheet (1) and the carrier plate (2).

[0075] With this invention, specifically assisting the cold bending of a thin glass sheet (1), cost of a manufacturing of a vehicle trim element (3) is reduced significantly as the two different processes are combined in the mold tool (100) of the present invention. Moreover, as the glass sheet (1) is supported on its front side, i.e., injection side is the back side, the injection process can be realized without any obstruction, in other words, there is no block / obstacle in the mold cavity (103) thanks to the present invention and more, the cleaning of any potential defects on the front side is possible afterwards.

[0076] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The foregoing description details certain embodiments of the invention. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the invention may be practiced in many ways. The invention is not limited to the disclosed embodiments.

Claims

CLAIMS1. A mold tool (100) for plastic injection molding process comprising a mobile core (101) and a base core (102) of which at least one core (101, 102) configured to move and abut the other, a mold cavity (103) configured to be provided inbetween the mobile core (101) and base core (102), at least one injection channel (104) for injecting plastic material into the mold cavity (103) characterized in that a plurality of openings (105) provided on a surface of at least one core (101, 102) facing the other, configured to provide suction.

2. A mold tool (100) for plastic injection molding process according to claim 1 or 2, characterized in that diameter of the openings (105) is in the range of 0,5 to 10 mm.

3. A mold tool (100) for plastic injection molding process according to any preceding claims, characterized in that the distance between adjacent openings (105) is in the range of 1 to 50 mm.

4. A mold tool (100) for plastic injection molding process according to any preceding claims, characterized in that the openings (105) facing inside the mold cavity (103).

5. A mold tool (100) for plastic injection molding process according to any preceding claims, characterized in that the openings (105) uniformly spread on the surface of the core (101, 102).

6. A mold tool (100) for plastic injection molding process according to claims 1 to 4, characterized in that the openings (105) nonuniformly spread on the surface of the core (101, 102).

7. A mold tool (100) for plastic injection molding process according to any preceding claims, characterized in that the core (101, 102) comprises a top block (106) wherein the openings (105) provided and a base block (107) wherein the top block (106) attached.

8. Use of the mold tool (100) for plastic injection molding process according to any preceding claims, for cold bending of a thin glass sheet (1).

9. A method for cold bending of a thin glass sheet (1) using a mold tool (100) for plastic injection molding process according to any preceding claims, characterized by the steps;- providing a carrier plate (2) onto the core (101, 102) of the mold tool (100),- providing a thin glass sheet (1) onto the core (101, 102) of the mold tool (100) with the openings (105) inline with the thin glass sheet (1),- providing suction of the thing glass sheet (1) via the openings (105),- providing a mold cavity (103) by moving at least one of the cores (101, 102) of the mold tool (100),- injecting plastic material into the mold cavity (103) to bond / fixthe carrier plate (2) and the thin glass sheet (1).

10. A method for cold bending of a thin glass sheet (1) according to claim 9, characterized in that the suction level selected proportional to the curvature value of the thin glass sheet (1).

11. A method for cold bending of a thin glass sheet (1) according to claims 9 or 10, characterized in that the distance between adjacent openings (105) selected inversely proportional to the thickness of the thin glass sheet (1).

12. A method for cold bending of a thin glass sheet (1) according to one of claims 9 to 11, characterized in that the distance between adjacent openings (105) selected inversely proportional to the curvature value of the thin glass sheet (1).

13. A vehicle interior and / or exterior trim element (3) comprising a thin glass sheet (1) and a carrier plate (2), manufactured by the method of claim 9 to 11.

14. A vehicle interior and / or exterior trim element (3) according to claim 13, characterized in that the thickness of the thin glass sheet (1) is less than 3mm, preferably less than 2 mm, more preferably less than 1,5 mm.

15. A vehicle interior and / or exterior trim element (3) according to claim 13 or 14, characterized in that the carrier plate (2) being plastic or metallic, injected plastic material being soft plastic.

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