JPH0250141B2 - - Google Patents

Description

[Detailed description of the invention]

〓Field of Industrial Application〓 The present invention is a thin film-like flame-retardant thermoplastic composite with a thickness of 0.1 mm, which has high strength and toughness, has excellent roll-formability, and is rich in flame retardant, heat-insulating, and sound-absorbing properties. Regarding resin film. 〓Conventional technology〓 Conventional flame retardant technology for synthetic resin films is as follows:
A method of blending flame retardants such as halogen compounds, phosphorus-containing compounds, nitrogen-containing compounds, and antimony oxide with synthetic resin raw materials is used, but such flame retardants are relatively expensive. Moreover, there is a danger that harmful gases may be emitted when the film is formed or exposed to high temperatures. In recent years, attempts have been made to make films flame retardant by using such non-hazardous inorganic fillers as fillers in synthetic resins; In this case, it is necessary to incorporate a large amount into the resin, which deteriorates the strength of the film and reduces the moldability of the film, making it impossible to obtain a thin film with a thickness of 0.1 mm. In order to improve this, attempts have been made to reduce the amount of inorganic filler by using the flame retardant and inorganic filler together, but not only is it difficult to obtain a sufficient flame retardant effect, but also thermoplastic The amount of inorganic filler used in the synthesis also cannot be reduced to a significant extent.
For this reason, attempts have been made to reduce the amount of inorganic filler blended, but these efforts have not been sufficiently effective and have not directly led to improvements in film moldability or performance. On the other hand, in order to improve the moldability of the film, relatively low molecular weight synthetic resins are sometimes added.
Since low molecular weight synthetic resins have a low softening point, the toughness of the film decreases. In addition, various lubricants and plasticizers such as aluminum stearate and metal soap are sometimes added, but these do not substantially improve the flame retardance and toughness of the film. 〓Problems to be solved by the invention〓 This invention solves problems that could not be solved by conventional flame-retardant synthetic resins, such as the generation of harmful gases that occur during molding or when exposed to high temperatures. The purpose of the present invention is to obtain a thin synthetic resin film that has high flame retardancy, toughness, heat insulation, and sound absorption properties without deterioration of moldability or deterioration of film strength and toughness caused by chemical reaction. 〓Means for solving the problem〓 30-60% by weight of a thermoplastic synthetic resin that does not contain halogen and has a glass transition temperature of 50-120°C, and 5.3 parts by weight of colloidal inorganic fiber for 100 parts by weight of heat-dehydrated inorganic powder. 40 to 70% by weight of an inorganic filler containing ~43 parts by weight was mixed and formed into a thin film with a thickness of 0.1 mm. That is, the film of the present invention has a glass transition temperature of 50
~120°C, 30-60% by weight of halogen-free thermoplastic synthetic resin and 40-70% by weight of inorganic filler containing 5.3-43 parts by weight of colloidal inorganic fiber based on 100 parts by weight of heat-dehydrated inorganic powder. The desired thin film with a thickness of 0.1 mm was obtained by blending and mixing, preforming using an extruder, and rolling molding, but the glass transition temperature used here was 50 ~120°C, halogen-free thermoplastic synthetic resins such as polyethylene, polypropylene, polystyrene, polymethacrylate, polycarbonate, polyethylene terephthalate, and copolymers thereof are advantageously used, and thermally dehydrated inorganic powder The particle size is
Aluminum hydroxide, magnesium hydroxide, hydrated calcium sulfate, or a mixture thereof with a particle size of 40 μ or less is used, and it may be partially replaced with talc, clay, calcium carbonate, etc., as long as it does not impede flame retardancy and moldability. do not have. Furthermore, colloidal inorganic fibers include potassium titanate fiber, boron nitride fiber, calcium metasilicate (wollastonite, sepiolite, magnesian silicate natural inorganic fiber known as Hetdman Fiber (manufactured by Hetdman Co., Ltd., Canada), etc.). The fiber diameter is 3μ or less, the fiber length is 30μ or less, and the aspect ratio is about 10.However, in the film of the present invention, colloidal inorganic fibers are added to 100 parts by weight of the heat-dehydrated inorganic powder.
40 to 70% by weight of an inorganic filler mixed with 5.3 to 43 parts by weight, and 30 to 60% by weight of a halogen-free thermoplastic synthetic resin with a glass transition temperature of 50 to 120°C,
The mixture is mixed by heating and kneading using a pressure roll, kneader, or extruder, and then preformed using an extruder, and then continuously rolled into a thin film with a thickness of 0.1 mm using a rolling machine such as a calendar roll. do. In addition, known heat stabilizers, ultraviolet stabilizers, plasticizers, lubricants, antistatic agents, thickeners, dispersants, etc. may be appropriately added to the composition to the extent that they do not impede the properties required for the film. May be combined. 〓Example〓 Next, an example will be shown about the film of the present invention, and the results of measuring the flammability, tensile strength, elongation, moldability, and smoothness in order to know the flame retardance of the obtained film will be shown in the first part. Shown in the table.

【table】

[Table] Water type inorganic powder: Aluminum hydroxide, Colloidal inorganic fiber: Potassium titanate fiber The thermoplastic synthetic resin used was a crystalline polypropylene ethylene copolymer with a density of 0.865 and an ethylene content of 12%. used high-density polyethylene with a density of 0.945. As the heat-dehydrated inorganic powder that is one component of the inorganic filler, aluminum hydroxide (trade name: Hygilite, manufactured by Showa Denko K.K.) with an average particle size of 30 μm was used. However, in Examples 2-4 and 5-5, calcium carbonate having an average particle size of 30 μm was used. The colloidal inorganic fiber, which is the other component of the inorganic filler, is a colloidal potassium titanate fiber with a fiber diameter of 3μ or less, fiber length of 30μ or less, and an aspect ratio of 10 [trade name:
manufactured by Otsuka Chemical Co., Ltd.], and in Example 5-5, glass fiber powder with an average fiber diameter of 5 μm and an average fiber length of 100 μm was used. Each composition was heated and kneaded using a pressure kneader, and a preformed product was produced using an extruder. Next, the preformed product was placed in a calendar roll type rolling molding machine, heated and pressed at 160°C for 5 minutes, and then
Films with a thickness of 0.1 mm were rolled and molded, and cut into appropriate sizes, which were used as samples for flame retardancy testing and tensile strength measurements, and five sheets of each were prepared. . Flame retardancy was measured using the horizontal ignition flame method in accordance with the Ministry of Transport's ``Vehicle Material Combustion Test Standard FMVSS-302.'' Each sample was measured five times, the times for the five measurements were added, and the total number of seconds was displayed. The tensile strength is the thickness molded in the same manner as above.
A 0.1 mm film was cut to a width of 15 mm, a tensile test was conducted, and the strength at break at a width of 15 mm and elongation at break were expressed. Confirmation of moldability is determined by the moldability when continuously molding a 0.1 mm thick film using a calendar roll type rolling molding machine equipped with a preforming device using an extruder and the smoothness of the film after molding, and is classified into the following symbol categories. Displayed by. Moldability ◎ Easily moldable 〇 Suitable for molding △ Can be made into sheets continuously regardless of appearance × Things that cannot be molded Smoothness ◎ Extremely smooth 〇 There is a small amount of hard eyes, but this is a problem in use Items that do not have △ Items that have pinholes, hard eyes, and poor topography × Items that have holes, bumps, etc. and are unusable As is clear from this table, heat-dehydrated inorganic materials are used as inorganic fillers for thermoplastic synthetic resins. When mixing only powder, the higher the mixing ratio, the lower the flammability and the higher the flame retardancy, but the lower the breaking strength and elongation, and the lower the film formability.
The smoothness of the film rapidly deteriorates and the film breaks or tears during rolling. On the other hand, 40-70% by weight of an inorganic filler consisting of heat-dehydrated inorganic powder and colloidal inorganic fiber is mixed with 30-60% by weight of thermoplastic synthetic resin, and after being preformed using an extruder, The film of the present invention that has been rolled and molded shows that as the amount of inorganic filler increases, the flame retardance decreases and the flame retardance improves, the breaking strength increases slightly, and the degree of elongation at break decreases, but There is no problem in film properties and film smoothness, and stable production is possible.Moreover, the greater the amount of inorganic filler, the lower the flammability, that is, the higher the flame retardance, and the higher the breaking strength. If the amount of inorganic filler is less than 40% by weight, flame retardant problems will occur, and if it exceeds 70% by weight, the breaking strength of the film will decrease, and the smoothness of the film will also deteriorate, causing the film to break or tear. wake up In addition, when the amount of colloidal inorganic fiber is less than 5.3% by weight based on 100 parts by weight of heat-dehydrated inorganic powder, the proportion of colloidal inorganic fiber to heat-dehydrated inorganic powder decreases, so the fine powder that occupies the film decreases. The amount of colloidal inorganic fibers increases, the film is not strengthened by the colloidal inorganic fibers, the strength of the film decreases, and the formability and surface smoothness of the film deteriorate.
If it exceeds % by weight, the ratio of colloidal inorganic fibers to the heat-dehydrated inorganic powder increases, resulting in an increase in the number of overlapping and entangling portions of colloidal inorganic fibers, which deteriorates the formability and surface smoothness of the film. It is not possible to obtain a film with characteristics such as uniform thickness, thinness, and strength sufficient for practical use. 〓Effects of the invention〓 As described in detail above, the glass transition temperature is 50~
Halogen-free thermoplastic resin at 120℃
30 to 60 parts by weight of inorganic filler containing 5.3 to 43 parts by weight of colloidal inorganic fibers to 100 parts by weight of heat-dehydrated inorganic powder are blended and mixed to form a thin film with a thickness of 0.1 mm. The film of the present invention molded into
Film formability Particularly, it can be formed into a thin film with a thickness of 0.1 mm by rolling.The obtained film has excellent surface smoothness, is flame retardant, does not emit harmful gases, and is made of inorganic materials. The combination of fillers, especially heat-dehydrated inorganic powder and colloidal inorganic fibers, provides high strength and toughness, as well as flame retardancy and
It has excellent heat-insulating and sound-absorbing properties, and is especially effective when used as a surface decorative film for interior materials.

Claims (1)

[Claims] 1. Inorganic filler containing 30-60% by weight of a thermoplastic synthetic resin with a glass transition temperature of 50-120°C and no halogen, and 5.3-43 parts by weight of colloidal inorganic fiber per 100 parts by weight of heat-dehydrated inorganic powder. Material 40~70
A flame-retardant thermoplastic synthetic resin film formed into a thin film with a thickness of 0.1 mm.