摘要:
The heat shrinkable polypropylene film having an isotactic polypropylene layer as surface layers and a layer mainly composed of a syndiotactic polypropylene as an intermediate layer, having a shrinkage of not less than 25% at 100.degree. C. in the machine and transverse directions and being stretched at least two times in the machine and transverse directions, respectively. The film has a good packaging machine applicability and excellent propagation tear resistance, low temperature shrinkability and heat resistance, and is suitably used as a shrink packaging material.
摘要:
A heat shrinkable polyolefin laminate film having surface layers made of a crystalline polypropylene resin, and an intermediate layer made of an ethylene resin composition consisting essentially of a linear low density polyethylene and a syndiotactic polypropylene, which is stretched at least two times in the machine and transverse directions, respectively, and which does not cause lowering of the transparency even if recovered films are incorporated into the intermediate layer, is excellent in low temperature shrinkability and packaging machine applicability, and is suitably used as a heat shrinkable packaging material.
摘要:
A process for preparing N.sup.6, 9-disubstituted adenines which comprises reacting a metal salt of N.sup.6 -substituted adenine with a benzyl halide compound, preferably in the presence of a phase transfer catalyst. According to the process, the N.sup.6,9-disubstuted adenines can be obtained in high yields and good selectivity.
摘要:
A multi-layer film having an intermediate layer containing, as a main component, a mixture of two kinds of specific linear low density polyethylenes, and innermost and outermost layers containing, as a main component, a mixture of a specific high pressure process polyethylene, a specific ethylene-.alpha.-olefin copolymer and a specific linear low density polyethylene. The film has an automatic packaging machine applicability and an excellent heat sealability at low temperatures without defects such as lowering of tuck in property, stretchability in the transverse direction and film slipping property and blocking, and is suitably employed as films for stretch packaging and shrink packaging which are used for prepackaging of retailed goods, mainly foods. Further, a multi-layer film prepared by incorporating a specific surfactant composition into at least two layers of the above multi-layer film has, in addition to these properties, an excellent antifogging effect (initial antifogging property and retainability of antifogging property) on various objects to be packaged.
摘要:
A biaxially stretched film of an ethylene copolymer, preferably a mixture of (A) 90 to 50% by weight of a linear ethylene-.alpha.-olefin copolymer having a density of 0.90 to 0.93 g/cm.sup.3 at 25.degree. C. and a melt index of 0.2 to 3.0 g/10 min. and (B) 10 to 50% by weight of an ethylene polymer having a density of 0.87 to 0.91 g/cm.sup.3 at 25.degree. C. and less than the density of the copolymer (A) by at least 0.014 g/cm.sup.3 and a melt index of 0.2 to 5.0 g/10 min., said copolymer or copolymer mixture giving a DSC curve with an endothermic area under the temperature lower than its melting temperature (main endothermic peak temperature) by 10.degree. C. accounting for at leat 55% of the total endothermic area. The stretched film is little varying in thickness and is excellent in heat shrinkability at low temperature.
摘要翻译:乙烯共聚物的双轴拉伸膜,优选(A)在25℃密度为0.90〜0.93g / cm 3的线性乙烯-α-烯烃共聚物的90〜50重量%的混合物,熔体指数 为0.2〜3.0g / 10min。 和(B)10至50重量%的在25℃密度为0.87至0.91g / cm 3的乙烯聚合物,并且小于共聚物(A)的密度至少为0.014g / cm 3,熔体 指数为0.2〜5.0g / 10min,所述共聚物或共聚物混合物在低于其熔融温度(主吸热峰温度)的温度下提供具有吸热面积的DSC曲线10℃,占55% 总吸热面积。 拉伸膜的厚度变化不大,在低温下的热收缩性优异。
摘要:
A stretchable, heat shrinkable ethylene-.alpha.-olefin copolymer film which has excellent stretchability as well as shrinkability at a low temperature and is useful as a good packaging material is prepared by melt extruding a composition including at least one ethylene-.alpha.-olefin copolymer as a main component to give a non-stretched film and biaxially stretching the film in a temperature region where an orientation can be induced and at an area stretching ratio of not less than 8 under conditions such that a tensile strength is from 30 to 170 kg/cm.sup.2. The film has an index of refraction N of 1.500 to 1.522, a degree of orientation Wk according to X-ray diffraction method of 0.78 to 0.93 and an area shrinkage of not less than 15% at 90.degree. C.
摘要翻译:通过将包含至少一种乙烯-α-烯烃共聚物的组合物熔融挤出成为包含至少一种乙烯-α-烯烃共聚物的组合物来制备在低温下具有优异的拉伸性和可收缩性的可伸缩的热收缩乙烯-α-烯烃共聚物膜, 在拉伸强度为30〜170kg / m 2的条件下,在可以诱导取向的温度区域中以不小于8的面积拉伸比得到非拉伸膜并双轴拉伸膜的主要成分, cm2。 该膜的折射率N为1.500〜1.522,根据X射线衍射法的取向度Wk为0.78〜0.93,90℃下的面积收缩率为15%以上。
摘要:
A process for preparing a heat shrinkable film which is made from a copolymer of ethylene and 0.5 to 10% by mole of an .alpha.-olefin having 4 to 12 carbon atoms, the copolymer having a g* value (i.e., intrinsic viscosity of the copolymer/intrinsic viscosity of a linear polyethylene having the same molecular weight) of 0.3 to 0.7, a melt index of 0.3 to 2.0 g/10 min., and a density at 25.degree. C. of 0.86 to 0.92 g/cm.sup.3, wherein a tubular film of the copolymer is stretched under the following conditions:(A) the film surface temperature at the starting point of expansion being within the range of 20.degree. to 30.degree. C. below the melting temperature;(B) the film in a stretching zone extending from the starting point to the finishing point of expansion having a temperature gradient such that the film surface temperature at a position of 1/4 to 1/3 the vertical length (L) of the stretching zone from the starting point is maximum, and the difference between the maximum film temperature and the film temperature at the starting point of expansion being not more than 5.degree. C.;(C) the temperature drop of the film from the maximum temperature position to the finishing point of expansion being within the range of 15.degree. to 20.degree. C.; and(D) the film being cooled rapidly so that its temperature drops to a value of not more than 60.degree. C. while traveling from the finishing point to a distnace of 0.8 time the vertical distance of the stretching zone.
摘要:
According to the method of the present invention, the clean gas is supplied between the support and the plate-like body to form the pressurized space, thereby preventing the surface of the support from being exposed to dust and allowing a conveyance path to be maintained at desired cleanliness. Specifically, the pressurized space between the support and the plate-like body is at the atmospheric pressure or higher, thereby preventing dust from being introduced.
摘要:
The present invention relates to a biaxially stretched film whose main component is a linear low density polyethylene showing, in measurement of a melting point by a differential scanning calorimeter, a main peak temperature (Tma) within the range of 118.degree..+-.5.degree. C. in a melting curve obtained when after a temperature of the polyethylene is kept at 190.degree. C. for 30 minutes, the temperature is dropped down to 20.degree. C. at a cooling rate of 100.degree. C./minute and subsequently raised at a heating rate of 10.degree. C./minute (hereinafter referred to as "melting curve after rapidly cooling") and showing a temperature difference between Tma and Tmb of at least 3.degree. C. wherein Tmb is a main peak temperature in a melting curve obtained when after the temperature of the polyethylene is kept at 190.degree. C. for 30 minutes, the temperature is dropped down to 20.degree. C. at a cooling rate of 10.degree. C./minute and subsequently raised at a heating rate of 10.degree. C./minute (hereinafter referred to as "melting curve after gradually cooling") (hereinafter referred to as "lowered melting point polyethylene in rapidly cooling"). Since this film is excellent in stability on stretching, the stretching can be stably conducted by a low tensile strength upon stretching, as a result a stretched film having excellent stretchability and shrinkability, and having excellent elastic restoration can be obtained.
摘要:
An extraction residue obtained by solvent deasphalting of a residual oil is mixed with a carrier gas and thermally cracked at a temperature of 400.degree. C. to 600.degree. C. in a tube-type cracking apparatus to obtain cracked oil and pitch. The use of the carrier gas, which may be either an inert gas such as nitrogen or a reactive gas such as hydrogen, permits a flow velocity through the cracking apparatus sufficient to substantially prevent coking. Preferably, the cracking conditions are controlled so that the yield of cracked oil is not more than about 30 to 35%.