CN103485073B - Automotive trim panel the sandwich layer system of processing of natural-fiber composite material felt and technique - Google Patents

Abstract

The invention discloses a processing system and process for a natural fiber composite material felt used for the core layer of an automobile interior trim panel. The system includes a fiber web generating device connected to an oven through a bottom curtain. The bottom curtain is provided with a driving structure, and the oven comes out. The fiber web passes through the hot-pressing device and is extended to the winding device. The oven is provided with a fabric guide roller and a support delivery roller for winding the fiber web into an S shape. The hot-pressing device is a pair of heated and pressurized rotating rollers. The fiber web forming device described above includes an opening device, a carding device and a web laying device connected in sequence. The invention is a low-cost, high-performance, environment-friendly technology for the preparation of natural fiber composite felts for the core layer of automotive interior panels, which can greatly improve the strength and toughness of natural fiber composite felts, and can be used as a felt with high strength requirements. The substrate of various types of automotive interior panels.

Description

Processing system and technology of natural fiber composite felt for core layer of automotive interior panels

technical field

The invention relates to a natural fiber composite material felt, in particular to a processing system and process for a natural fiber composite material felt for automotive interior panels, and belongs to the field of fiber composite material preparation.

Background technique

At present, the materials used to manufacture the substrates of automotive interior panels are mostly chemical synthetic materials such as polypropylene and polyurethane. On the one hand, the natural resources for preparing these materials are limited, non-renewable, and pollute the environment during processing; With the development of light weight, high strength, environmental protection and recyclability, the original polypropylene board and its composite board with wood powder and polyurethane board can no longer meet the needs of modern automobile development, so various natural fibers are further recognized by people And into the field of auto parts production.

Some natural fibers such as hemp fiber and palm fiber can be used as heat insulation, sound insulation and damping materials; especially when these natural fibers are used as filling and reinforcement materials for polymer matrix composites, because of their light weight, low price, environmental friendliness, It is favored by automobile manufacturers due to its advantages such as non-brittle fracture. Using this kind of mixing-gluing-hot-pressing technology of natural fibers and chemical synthetic fibers, fiber sheets for automotive interior parts can be processed, and its product characteristics are similar to those of traditional polypropylene sheets and their composite sheets with wood powder and polyurethane sheets. Compared with other products, it is newer, more practical, non-toxic and environmentally friendly, light in weight, good in hygroscopicity, and low in production cost.

The processing method of natural fiber composite board is usually to mix natural fiber and chemical fiber into felt and then heat press molding. The current fiber mats mostly adopt needle-punching pre-setting method. In the material preparation stage, independent pieces of rectangular fiber mats are obtained, and then hot-pressed one by one on the composite mold, which lacks the integrated design of composite material preparation and molding processing. , did not give play to the more direct help of the material preparation stage to the material forming stage, resulting in a low degree of automation during hot pressing, requiring additional and complicated conveying mechanisms, grippers, and positioners. The labor intensity of the workers is high, and the product quality is unstable. Production costs are high.

Contents of the invention

The purpose of the present invention is to overcome above-mentioned deficiencies in the prior art, provide a kind of processing system and technology of the natural fiber composite material mat for the core layer of automobile interior trim board.

To achieve the above object, the present invention adopts the following technical solutions:

The processing system of natural fiber composite felt for the core layer of automotive interior panels includes a fiber web generating device, which is connected to an oven through a bottom curtain, and the bottom curtain is equipped with a driving structure, and the fiber web coming out of the oven is extended to Winding device, the oven is provided with cloth guide rollers and supporting conveying rollers that wind the fiber web into an S shape, the hot pressing device is a pair of rotating rollers that can be heated and pressed, and the fiber web generating device includes sequentially Connected opening unit, carding unit and web laying unit.

The oven is provided with a spraying device for spraying additives on both sides of the fiber web.

The opening device is an opening machine, the carding device is a carding machine, and the web laying device is a web laying machine. The outlet of the opening machine is connected to the cotton mixing box through a fan, and the carding machine is provided with messy rollers to improve the fiber-free The degree of sequence entanglement increases the mechanical properties of the fiber web. The web-laying machine includes a web-laying curtain, and a bottom curtain is provided under the web-laying machine. The bottom curtain is provided with a driving structure, and the output end of the bottom curtain is located at the bottom of the oven.

Pressure rollers with adjustable gaps are also installed in the oven to gradually reduce the thickness of the natural fiber composite mat obtained after drying.

The spraying device is two sets of linear reciprocating nozzles, which are respectively installed at the entrance of the oven and above the "S"-shaped intermediate layer in the oven.

The process of applying the above-mentioned device for processing comprises the following steps:

After opening all kinds of fibers required by the opening device and mixing evenly in the cotton mixer, they are continuously sent to the carding device for carding, and then the web is laid by the web laying device, and the laid continuous fiber web is transported by the bottom curtain to the Heating in an oven, heating at 110-135°C until part of the fibers are heated and melted, so as to bond various fibers in the mixed fiber, and then heat-pressed and shaped by a pair of adjustable gap rotating rollers at 200-250°C, and then wound after cooling.

When the fiber web is sent into the oven, additives are sprayed on the upper surface and the lower surface of the fiber web respectively. The heating action of the oven accelerates the evaporation of water from the sprayed additives. The additives are preferably flame retardants, bacteriostats or a mixture of both. The antibacterial agent is preferably organosilicon quaternary ammonium salt antibacterial agent, and the flame retardant is phosphorus nitrogen flame retardant, preferably guanidine phosphate.

The fiber composition required in the above process is: 5-35 parts of basalt fiber and/or glass fiber, 5-35 parts of surface-modified natural plant fiber, 15-35 parts of polyester fiber, 15-35 parts of low melting point sheath-core composite fiber 25 parts, 15-25 parts of high melting point fiber, the melting point difference between the high melting point fiber and the low melting point sheath-core composite fiber is greater than 20°C.

The low melting point sheath-core composite fiber is ES fiber, 4080 fiber, EfpakalL90 fiber, N40 fiber, polyethylene fiber or polyester fiber with sheath-core structure. Preferably, ES fibers and 4080 fibers with a sheath-core structure. 4080 fiber (the skin layer is 50% polyester with low melting point, and the core layer is 50% semi-dull polyester). Low-melting polyester is a random copolymerized modified polyester with a relatively low melting point. It is a raw material for producing thermally bonded fibers, and its melting point is generally 110-135°C. It can be heated and melted at a lower temperature to bond other fibers, especially this sheath-core composite low-melting point sheath-core composite fiber will not bond like a single-component low-melting point sheath-core composite fiber The phenomenon of melting and shrinkage occurs, and the core layer can still maintain a fibrous shape when the skin layer is melted. Low-melting point composite fiber ES fiber is also a typical skin-core structure (the skin layer is polyethylene, with a melting point of about 130°C, and the core layer is polypropylene, with a melting point of about 160°C).

The high-melting-point fiber has better strength, wear resistance, and higher modulus of elasticity, preferably polypropylene fiber, and it has good acid resistance, alkali resistance, and corrosion resistance, low density, low price, and is easy to recycle. It plays a bonding role during shaping, and can meet the needs of the thermal molding process of automotive interior panels.

The surface-modified natural plant fiber uses maleic anhydride-polypropylene (MAH-PP) copolymer as a grafting agent, and the hydroxyl group in the natural plant cellulose and the carboxyl group of maleic anhydride are esterified and grafted. Sex gets. The natural plant fiber is one or more of hemp fiber, palm fiber and wood fiber.

In the oven, the fiber web is conveyed forward by a row of supporting conveying rollers rotating in the same direction, and its conveying direction is changed by the fabric guide rollers rotating clockwise or counterclockwise. By adjusting the gap between the pressing rollers, the natural fiber composite The thickness of the material mat; after that, a pair of heated and pressurized rotating rollers is used to further control the thickness of the natural fiber composite mat and make the surface smooth, improving the appearance performance and dimensional accuracy of the product.

The beneficial effect of the present invention is,

The present invention adopts the method of thermal bonding and reinforcement of skin-core composite fibers with low melting point to prepare continuous and strip-shaped natural fiber composite mats, which facilitates subsequent hot-pressing molding, improves production automation and product quality stability, and greatly simplifies operations. Forming devices such as personnel and conveying mechanisms, grippers, positioners, etc. The invention is a low-cost, high-performance, environment-friendly technology for preparing natural fiber composite felt for the core layer of automotive interior panels, which can greatly improve the strength and toughness of the natural fiber composite felt, and can be used as a felt with high strength requirements The base material of various types of automotive interior panels.

Description of drawings

Fig. 1 is the top view of processing system of the present invention;

Fig. 2 is the front view of processing system of the present invention;

Among them: 1. Fiber web generating device, 2. Bottom curtain, 3. Spraying device, 4. Oven, 5. Heating and pressurizing rotating roller, 6. Natural fiber composite felt, 7. Winding device, 8. Driving structure, 9 . Cloth guide roller, 10. Support conveying roller, 11. Pressure roller.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings. It should be noted that the following description is only for explaining the present invention and not limiting its content.

Example 1:

As shown in Figure 1, the processing system for the natural fiber composite mat used in the core layer of automotive interior panels includes a fiber web generating device 1, and the fiber web generating device 1 is connected to an oven 4 through a bottom curtain 2, and the bottom curtain 2 is provided with a driving structure 8 , the fiber web coming out of the oven 4 is extended to the winding device 7 through the hot pressing device, and the oven 4 is provided with a cloth guide roller 9 and a support delivery roller 10 that wind the fiber web into an S shape, and the hot pressing device is a pair of Heating and pressing the rotating roller 5, the fiber web forming device 1 includes an opening device, a carding device and a web laying device connected in sequence.

The opening device is an opening machine, the carding device is a carding machine, and the web laying device is a web laying machine. The outlet of the opening machine is connected to the cotton mixing box through a fan. The degree of knotting increases the mechanical properties of the fiber web. The web-laying machine includes a web-laying curtain, and a bottom curtain is provided under the web-laying machine. The bottom curtain is provided with a driving structure, and the output end of the bottom curtain is located at the bottom of the oven. The pressure roller 11 with adjustable gap size is also installed in the oven, which is used to gradually reduce the thickness of the natural fiber composite felt after drying.

The process of processing with the above-mentioned device, the steps are as follows:

After the required fibers are opened by the opening device and mixed evenly in the cotton mixer, they are continuously sent to the carding device for carding, and then laid by the web-laying device, and the laid continuous fiber web is transported to the oven by the bottom curtain Heating, heating at 110-135°C until part of the fibers are heated and melted, so that various fibers in the mixed fibers are bonded to form a natural fiber composite felt, and then heat-pressed and shaped by a pair of adjustable gap rotating rollers at 200-250°C, after cooling Winding. The required fiber composition is: surface modified hemp fiber 25kg, basalt fiber 15kg, hot melt fiber 408018kg, polypropylene fiber 17kg, polyester fiber 25kg.

The low-melting point sheath-core composite fiber is hot-melt fiber 4080, the skin layer is low-melting point polyester, and the core layer is semi-dull polyester. To bond each fiber, and the core layer, as a skeleton, can still maintain the fiber shape when the skin layer is melted, so that it will not produce shrinkage phenomenon like a single-component low-melting point sheath-core composite fiber. The present invention uses a low-melting point The sheath-core composite fiber is used as the binder in the preparation stage of the natural fiber composite fiber mat 6 .

When the natural fiber composite mat 6 is used for thermoforming, the low-melting point sheath-core composite fiber and the high-melting point fiber are both heated and melted, and together play the role of an adhesive. After cooling, it can be relatively dense, with high rigidity and strength. Composite automotive interior panels.

In the oven 4, the fiber web is conveyed forward by a row of supporting conveying rollers 10 rotating in the same direction, and its conveying direction is changed by the cloth guide roller 9 rotating clockwise or counterclockwise. Reduce the thickness of the natural fiber composite felt 6; after that, utilize a pair of heated and pressurized rotating rollers 5 to further control the thickness of the natural fiber composite felt 6, and make the surface smooth to improve the appearance performance and dimensional accuracy of the product.

Example 2

As shown in Fig. 1 and Fig. 2, the processing system of natural fiber composite felt for the core layer of automobile interior trim includes a fiber web generating device 1, and the fiber web generating device 1 is connected to an oven 4 through a bottom curtain 2, and the bottom curtain 2 is equipped with The driving structure 8, the fiber web coming out of the oven 4 is extended to the winding device 7 through the hot pressing device, and the oven 4 is provided with a cloth guide roller 9 and a supporting conveying roller 10 for winding the fiber web into an S shape. The hot pressing device It is a pair of heated and pressurized rotating rolls 5, and the fiber web generating device 1 includes an opening device, a carding device and a web laying device connected in sequence.

The opening device is an opening machine, the carding device is a carding machine, and the web laying device is a web laying machine. The outlet of the opening machine is connected to the cotton mixing box through a fan. The degree of knotting increases the mechanical properties of the fiber web. The web-laying machine includes a web-laying curtain, and a bottom curtain is provided under the web-laying machine. The bottom curtain is provided with a driving structure, and the output end of the bottom curtain is located at the bottom of the oven. The pressure roller 11 with adjustable gap size is also installed in the oven, which is used to gradually reduce the thickness of the natural fiber composite felt after drying.

The oven is provided with a spraying device 3 for spraying additives on both sides of the fiber web. The spraying device is two sets of linear reciprocating nozzles, which are respectively installed at the entrance of the oven and above the "S"-shaped intermediate layer in the oven.

The process of processing with the above-mentioned device, the steps are as follows:

After the required fibers are opened by the opening device and mixed evenly in the cotton mixer, they are continuously sent to the carding device for carding, and then laid by the web-laying device, and the laid continuous fiber web is transported to the oven by the bottom curtain Heating, heating at 110-135°C until part of the fibers are heated and melted, so as to bond various fibers in the mixed fiber, and then heat-pressed and shaped by a pair of adjustable gap rotating rollers at 200-250°C, and then wound after cooling. When the fiber web is sent into the oven, additives are sprayed on the upper surface and the lower surface of the fiber web respectively. The heating action of the oven accelerates the evaporation of water from the sprayed additives. The additive is a mixture of flame retardant and antibacterial agent. The antibacterial agent is preferably organosilicon quaternary ammonium salt antibacterial agent, and the flame retardant is phosphorus nitrogen flame retardant, preferably guanidine phosphate. The required fiber composition is: surface modified wood fiber 35kg, basalt fiber 10kg, hot melt fiber 408020kg, polypropylene fiber 20kg, polyester fiber 23kg.

In the oven 4, the fiber web is conveyed forward by a row of supporting conveying rollers 10 rotating in the same direction, and its conveying direction is changed by the cloth guide roller 9 rotating clockwise or counterclockwise. Reduce the thickness of the natural fiber composite felt 6; after that, utilize a pair of heated and pressurized rotating rollers 5 to further control the thickness of the natural fiber composite felt 6, and make its surface smooth to improve the appearance performance and dimensional accuracy of the product.

Although the specific implementation of the present invention has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the present invention. On the basis of the technical solution of the present invention, those skilled in the art can make various Modifications or variations are still within the protection scope of the present invention.

Claims (7)

1. The processing system of natural fiber composite felt for the core layer of automotive interior panels, characterized in that it includes a fiber web generating device, the fiber web generating device is connected to the oven through the bottom curtain, the bottom curtain is provided with a driving structure, and the fiber web coming out of the oven It is extended to the winding device through the hot pressing device. There are cloth guide rollers and supporting conveying rollers that wind the fiber web into an S shape in the oven. The hot pressing device is a pair of heating and pressing rotating rollers. The fiber web The generating device includes an opening device, a carding device, and a web laying device connected in sequence; the oven is provided with a spraying device for spraying additives on both sides of the fiber web, and the spraying device is two sets of linear reciprocating nozzles, which are respectively installed in the oven. The inlet and the top of the "S"-shaped middle layer in the oven, and the pressure roller with adjustable gap size is also installed in the oven. 2. The processing system of the natural fiber composite material felt for the core layer of automobile interior trim according to claim 1, wherein the opening device is an opening machine, the carding device is a carding machine, and the web laying device is a laying machine. The net machine, the outlet of the opener is connected to the cotton mixing box through the fan, the carding machine is equipped with messy rollers, the net lapper includes a net laying curtain, and a bottom curtain is provided under the net laying machine, and the bottom curtain is provided with a driving structure. The output end of the bottom curtain is located at the bottom inside the oven. 3. utilize the described system of claim 1 to carry out the process of processing, it is characterized in that, comprises the steps as follows: After the desired fiber is loosened through the opening device and mixed uniformly in the cotton mixer, it is continuously sent to the carding device for carding, Then the web is laid by the web laying device, and the laid continuous fiber web is transported to the oven by the bottom curtain for heating, and heated at 110-135 °C until part of the fibers are heated and melted, so as to bond various fibers in the mixed fiber, and then through a Heat-press the adjustable gap rotating roll at 200-250°C, and roll it after cooling. 4. The process according to claim 3, characterized in that, when the fiber web is sent into the oven, the upper surface and the lower surface of the fiber web are sprayed with additives. 5. The process according to claim 4, characterized in that the additive is selected from a flame retardant, a bacteriostat or a mixture of the two. 6. The process according to claim 3, wherein the required fiber composition is: 5-35 parts of basalt fiber and/or glass fiber, 5-35 parts of surface-modified natural plant fiber, 15-35 parts of polyester fiber 35 parts, 15-25 parts of low-melting point sheath-core composite fiber, 15-25 parts of high-melting point fiber, the melting point difference between the high-melting point fiber and the low-melting point sheath-core composite fiber is greater than 20°C. 7. The process according to claim 6, characterized in that, the low melting point sheath-core composite fiber is ES fiber, 4080 fiber, EfpakalL90 fiber, N40 fiber, polyethylene fiber or polyester fiber with a skin-core structure The natural plant fiber of described surface modification is to use maleic anhydride-polypropylene copolymer as grafting agent, the hydroxyl in the natural plant cellulose and the carboxyl generation of maleic anhydride are esterified and grafted and modified to obtain, so The natural plant fiber is one or more of hemp fiber, palm fiber and wood fiber.