環保油墨先鋒─黃豆油墨Pioneer of Environmentally Friendly Ink─Soy Ink Development in the World Market |
1979年美國報紙印刷者協會(American Newspaper Publishers' Association,目前改組為美國報紙協會Newspaper Association of America)的負責人提倡促進開發替代石油基質的印刷油墨(Printing ink)。當時由於OPEC (Organization of Petroleum Exporting Countries)環繞的有關事件使石油價格提升,而使其供應產生些問題,尤其油墨產業對於市場供應問題甚為敏感,以免影響其原料的供應。經幾年積極努力研討,黃豆油墨(Soy ink或稱Vegetable ink)被引進報紙產業使用。經研究採用許多種配方替代植物性油墨,黃豆油墨終於被認為無毒可應用,而且在烹調用的黃豆油(即大豆油)產量豐富,價格便宜(尤其在美國),安全性可靠,印刷效果良好並且符合印刷油墨的各項標準規格,尤其環保性絕佳。 如此,黃豆油墨的採用,首推報紙產業,在美國大約有10,000家報社,其中三分之一已使用黃豆油墨,尤其較大的1,500家日報的九成以上已肯定其效果而採用之。 大部份的報紙,係供它做彩色印刷,而且因彩色黃豆油墨的價格比較可與石油系彩色油墨競爭,其印刷效果確實優異,顏色甚為亮麗並且環保性佳為其特點。黑色黃豆油墨可供為報紙印刷,就長期而言,其印刷效率好(印刷份數較多,可降低成本),乃將甚具競爭優勢並受好評。 除了報紙印刷以外,其他印刷,諸如張頁油墨(Sheet-fed ink)、熱固型油墨(Heat-set ink)、冷固型油墨(Cold-set ink)、商用表格印刷油墨(Business forms ink)以及凸版油墨(Flexographic ink)等,亦可予以採用黃豆油墨,其效果佳而仍需由各廠商自行密集研究其配方以應其需。在美國從1989年以來,其使用範圍逐漸擴大而大約五萬家印刷業者的四分之一,經常使用黃豆油墨。大致100家較大的油墨廠商至少生產一種黃豆油墨產品。除了美國,在歐洲、澳洲、日本、韓國、等諸國亦經推展使用黃豆油墨,並繼續促銷中。 如是,黃豆油墨正在引導印刷油墨業者,以製造低揮發性有機成份(VOCs, Volatile Organic Compounds)的產品油墨。蓋因石油系油墨含有多量的VOCs及毒性成份,係為嚴重影響空氣污染的元凶所致。石油系油墨的VOCs係經美國環保署(EPA)及其他政府機關認定為空氣污染源主要成份(Hazardous Air Pollutants, HAPs)而採用黃豆油墨可謂解決印刷產業的環保,排除空氣污染,而獲得健康與安全的絕佳方案。 近來〝綠色(Green)〞為影響環境的原動力(Driving force)而黃豆油墨乃可佔有其重要的角色與價值。不管其目標係清潔空氣或為減少對進口石油的依靠度,或為使用可永續生產的可再生並為生物可分解(Renewable and biodegradable)的植物資源,而於此所提倡的黃豆油墨均可達成其目的。美國正在趨向於更為嚴格的環保政策,因此使用黃豆油墨,係為達成其政策的一種重要手段,而其他先進國家亦皆然。 黃豆油墨含有不同比率的黃豆油,係由於黃豆提油所得而供為食用油或食品加工之用,其安全性甚為可靠。油墨製造廠係將這種原來為食用黃豆油(或其他乾性或半乾性植物油脂)與顏料(pigments)、樹脂(Resin)、臘質(Waxes)等混合以製造油墨,而以黃豆油取代傳統使用的石油系礦物油,以避免石油系礦物油所含揮發性有害成份而排除影響環境清潔的空氣污染,確保作業人員健康,同時避免在油墨印刷廠的作業環境受到同樣的負面影響。更進一步對讀者(如報紙讀者)而言,傳統油墨印刷的報紙,通常閱讀時,時常感覺到石化異味揮發成份的困擾,係為一般報紙讀者的感受,同時其手亦易沾污(沾黑),蓋因傳統報紙印刷的黑色成份耐擦性較差所致。當採用黃豆油墨印刷的報紙,均無上述兩項缺點而易受讀者肯定與歡迎,理所當然 (一)黃豆油墨的特點: 可供為推展與應用黃豆油墨擁有技術上及應用上的多元特點。它由於具有在技術上,比傳統的石油系油墨為優的特點,以致已形成新穎的油墨市場規模。 (A)技術特點:
(B)應用特性:
(二)黃豆油墨的種類與用法: 各種形式的印刷須配合使用不同配方的黃豆油墨,猶如不能使用汽油在柴油引擎車輛的道理一樣。因此,可研擬各種配方油墨,隨其需求而選擇採用。
(三)黃豆油墨使用現況與展望: 在美國依照Hazard Communication Standard,若油墨產品含有致癌物質超過0.1%,則必須在產品上予以標示,而報紙亦不例外。通常石油系礦物油含有較多量的多環芳香族碳氫化合物(Poly Aromatic Hydrocarbons, PAH),係屬於致癌物質之一,因為傳統石油系油墨的這種負面因素,致使美國印刷業逐漸趨向於使用低PAH的原料油脂所構成的植物油墨,並以耐擦性佳的報紙印刷為訴求,以致必須開發新穎的油墨。於此,黃豆油墨,乃因應而出,而被採用為替代石油系油墨的革新油墨。 另外,在熱固型印刷,可予以解決VOCs揮發所導致的環境清潔問題,並在彩色印刷方面賦予特殊濃厚亮麗外觀與改進,係為美國報紙協會所推舉與使用。於1992年美國清潔空氣修訂案(Clean Air Amendment)規定化學發揮物的排放對報紙油墨配方的影響而獎勵採用非石油系的油墨。由此導致石油系礦物油基質的油墨減產,卻引起其漲價,而使業者逐漸轉換採用黃豆油墨,以符合排放廢氣的清潔空氣規定。目前報紙用黃豆油墨的用量已消耗46百萬磅黃豆油,其所製造的黃豆油墨約佔全美國黑色印刷報紙用油墨市場的13%。據估計,若整個美國印刷產業全部採用黃豆油墨,則其所需黃豆油的消費將達457百萬磅,而可拓展黃豆油的工業利用並益於環保。 黃豆油墨,對於回收廢紙的脫油墨較容易而且比較不會損傷紙質,同時脫油墨後的廢油墨殘渣比石油系的場合容易分解(按黃豆油係生物可分解,而石油係生物不可分解的物質),以利排水處理作業,而可掌控排放水品質。如此,使黃豆油墨成為經濟有效的選擇,係可由無毒性而可再生的資源(黃豆油)來配製油墨所致。 由美國環保署(EPA)及職業安全與健康管理局(Occupational Safety & Health Administration, OSHA)所主管的進行的National Toxicological Program經提示採用石油系印刷油墨所導致的潛在致癌效應,以警告石油系油墨的毒性。也許採用石油系油墨印刷的報紙,將被要求貼上有毒警告的標示,以利提醒讀者注意與關心。然而黃豆油墨並非萬能,仍有些因素(如價格較高)尚待研議改善與考量,以利更為順利推廣。 在日本,其黃豆油墨的使用剛起步,經美國黃豆協會的宣導,1998年的消費者已達859公噸/年,今後將加倍成長,乃順應日本人愛情潔環保性的國民性所致。 松下電器公司為日本最大的黃豆油墨使用業者,在其全球的電器製品的包裝說明、型錄,均採用黃豆油墨予以印刷,以顯示該公司對環保的重視與關心。同時在其印刷品上均貼上〝Soy Seal〞標誌,而顯示其印刷油墨係採用環保的新穎黃豆油墨,利於人類環境的清潔與健康效果,可見其用心程度。大日本印刷公司及凸版印刷公司為日本第一流的大印刷公司,亦採用黃豆油墨印刷而各已達80億日圓的規模。在1998年世界冬季運動會在日本長野市舉行時,曾了以宣導其環保性,以利再拓展。在日本,推動各項環保活動,尤其積極無比。 目前在日本已有230家油墨廠生產黃豆油墨並已有175個單位使用它。東洋油墨公司及板田油墨公司在日本生產黃豆油墨並在台灣設有分公司,另從日本總公司進口日製黃豆油墨在台灣銷售並貼有〝Soy seal〞標誌以宣示對環保的關心。 在台灣,黃豆油為食用油脂的龍頭,扮演甚重要的角色,約佔總植物油脂消費市場的六~七成。食用油脂的需求穩定而且飽和,將可進一步開拓黃豆油的工業利用,使植物油脂更為貢獻工業界並利於環保。如是,植物油墨(黃豆油墨Soy Ink)將是更美好明天的最佳選擇。 (四)商標〝Soy Seal〞(黃豆油墨標籤): 由美國Monsanto公司設立〝Soy Seal〞商標(如圖示),以表示在各種產品,包括油墨及各種印刷品上均有黃豆油的存在。該公司經由美國National Soy Ink Information Center授權美國黃豆協會(American Soybean Association,簡稱ASA),以利各有關廠商辦理〝Soy Seal〞商標採用登記,以顯示黃豆油的工業上新環保用途。 使用該商標,只要依〝Soy Seal User Agreement〞登記則可,並不需任何費用。為什麼要標示〝Soy Seal〞?猶如通常使用回收再生紙,均附有〝回收紙張〞標示,以顯示愛惜資源與重視環保的觀念與共識而使用〝Soy Seal〞係顯示該油墨或 印刷品,係採用由永續可再生的植物性黃豆油為原料製造的油墨,可謂新環保油墨,利於宣示環保政策與觀念並促銷產品。 "Soy Seal" 標籤 〝標示採用黃豆油墨印刷〞〝標示含有黃豆油墨〞 近來由於國民所得提高,對生活環境品質的要求日益殷切,環保意識高昂,石油系產品與日常生活息息相關,而環保與健康問題均已成為全球性課題。採用新環保的黃豆油墨以替代石油系油墨,以利用於確保清潔美好的生活環境,將是另一項最佳選擇,益於環保。 (資料來源:United Soybean Board (USB), USA National Soy Ink Information Center, USA, American Soybean Association (ASA), USA. |
2010年5月26日 星期三
[印刷知識]環保油墨先鋒─黃豆油墨
[印刷知識]
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2010年5月24日 星期一
DESCRIPTION OF WOOD PULP PRODUCTS
DESCRIPTION OF WOOD PULP PRODUCTS Mechanical Pulp Mechanical pulps are characterized by the fact that a very high percentage of the original wood components are retained in the finished product. For this reason they are often termed high yield pulps, with yields usually in the 85-95% range. Due to the high yield, mechanical pulps contain a number of different types of wood particles of various shapes and sizes, resulting in highly opaque products with good printing properties. However, the high yield also results in the presence of large percentages of lignin in the pulp, which yellows when exposed to heat or ultraviolet light. Given this, products which contain mechanical pulps tend to discolor over time. Also, mechanical processes cause considerable damage to wood fibers and result in a relatively weak pulp. In order to achieve adequate sheet strength it is often necessary to add a longer fiber chemical pulp to the mechanical pulp. Following is a list of the major mechanical pulping processes: 1) Stone Groundwood Pulp (SGW) (roundwood) 2) Pressurized Groundwood (PGW) (roundwood) 3) Refiner Mechanical Pulp (RMP) (chip) 4) Thermomechariical Pulp (TMP) (chip) 5) Chemi-Thermomechariical Pulp (CTMP) (chip) Each of these pulps is produced at relatively low cost when compared to chemical pulps. Typical end uses include newsprint, directory paper, supercalendered papers and lightweight coated paper (LWC). The CTMP process can also produce a pulp of high bulk and absorbency and is used in products such as tissue, toweling, and disposable diapers. CTMP is also used in the production of some paperboard grades such as those used in liquid packaging. Bleached CTMP is believed to have significant potential in printing and writing grades such as forms paper, uncoated bond and some book grades. Chemical Pulp The main grades of chemical pulp are kraft and sulfite. Chemical pulping removes fibers from wood by dissolving the lignin which holds them together. In contrast, mechanical pulping separates the fibers by a grinding action, leaving much of the lignin in the pulp. Chemical pulps are much stronger since individual fibers are not damaged to the extent that they are with mechanical pulping methods. The removal of lignin results in lower yields, and is typically between 40-55%, therefore leading to higher wood consumptions per unit and higher wood costs. In addition to resulting in a relatively stronger pulp, the removal of lignin makes chemical pulp less likely to lose its brightness over time as compared to mechanical pulp. Kraft Pulp (Sulphate): Kraft pulp is noted for its superior strength characteristics and can be used in virtually all paper and paperboard grades in order to improve strength properties. In fact, the word kraft is the Swedish and German word for strength. Kraft pulp can be produced from both hardwood and softwood species and is used in bleached, semi-bleached and unbleached forms. Unbleached kraft is usually made with softwood and is used primarily in the furnish of kraft linerboard, wrapping paper and bag papers such as grocery bags. Semi-bleached kraft is used in the furnish of grades which do not require high brightness, such as newsprint and other groundwood based papers. Bleached kraft is used in a much wider range of products than either unbleached or semi-bleached. Its greatest importance is in the printing and writing grades. In these grades softwood kraft is used for its strength characteristics, while hardwood kraft, having shorter fibers, is used for its superior printing properties. Sulphite Pulp: Sulphite was the most important pulping method until the 1930's, when kraft pulp began to dominate because it was able to utilize a wide variety of wood species not suitable for sulphite pulping. Today, sulphite is used much less than kraft. Sulphite is not as strong as kraft and is typically used in products which require good sheet formation and moderate strength. Historically, sulphite has been most widely used in newsprint furnish. However, its importance in newsprint has been declining in recent years with the increasing use of stronger mechanical pulps such as TMP and CTMP. Semi-Chemical Pulp: There are several types of semi-chemical pulps in production, but the most important of these is Neutral Sulfite Semi-Chemical (NSSC). NSSC is made primarily from hardwood species and is noted for its exceptional stiffness. Its primary use is for the production of corrugating medium. Dissolving Pulp: Not used in papermaking, dissolving pulp is chemically converted for use in such products as rayon, cellophane, cellulose acetate, cellulose nitrate and carboxymethyl cellulose. Softwoods are the major raw material for dissolving pulps, but some hardwood is used. DESCRIPTION OF PAPER AND PAPERBOARD PRODUCTS Kraft Paper Kraft papers can be grouped into three general categories: 1) Unbleached Packaging 2) Bleached Packaging 3) Special Industrial Papers Unbleached and bleached packaging papers are used for products such as wrapping, grocery bag, shipping sacks and other converted papers. Basis weights for these grades depend greatly on the end use and can range from 30 to 80 lbs per 3000 ft2 (49 to 130 g/m2). Special industrial papers include papers used in the manufacture of abrasives, electrical insulators, gaskets, filters and many other products. Bleached specialty papers include grades such as glassine, greaseproof and vegetable parchment Linerboard Linerboard is a relatively light weight board used for the outer plies of corrugated box stock and also as wrapping paper. The furnish for linerboard can be either kraft pulp or recycled material, usually old corrugated containers (OCC) or double lined kraft (DLK). The standard basis weight for linerboard is 42 lbs per 1000 ft2 (205 g/m2), but can range from 26 to 90 lbs. Linerboard is made with two layers and is typically manufactured on a two-headbox fourdrinier paper machines. In kraftliner, a lower quality high yield, unbleached kraft base sheet is formed from the first headbox. A better quality, lower yield layer is formed on top of the base sheet to provide a good printing surface. Where appearance is particularly important, mottled white, white top, bleached or coated liner can be used, depending upon the desired printing surface. Mottled white and white top liner have a top layer which is bleached, the top layer of mottled white liner does not provide full coverage of the base sheet, causing a "mottled" appearance, whereas white top does. With bleached liner, both the base and the top sheet are bleached. Coated liner is typically an unbleached liner with a white pigment coating. Corrugating Medium Corrugating medium is a light weight board used for the fluted inner plies of corrugated box stock. The basis weight for corrugating medium range from 18 to 36 lbs per 1000 ft2, with the standard being 26 lbs. Corrugating medium is typically made with semi-chemical pulp and or recycled material. About 75% of production utilizes a furnish containing about 80% semi-chemical pulp and 20% recycled fiber. The remainder of the production is made of 100% recycled material and is often termed "bogus medium". Boxboard Boxboard is a broad category encompassing coated and uncoated kraft paperboard, recycled paperboard and bleached paperboard. These boards have a wide range of basis weights, depending greatly upon the end use products. Typical end use products for kraft and recycled paperboard include beverage carriers, folding cartons, setup boxes, as well as tube, can and drum stock. Bleached kraft paperboard is commonly called solid bleached sulphate (SBS). The primary use for SBS is folding carton and milk carton. Other uses include disposable cups, plates and food containers. Newsprint Newsprint is an uncoated printing paper in which mechanical pulp and/or deinked recycled fiber is the main furnish component. The most common recycled furnish used is old news papers (ONP). Some chemical pulp is usually added to the sheet in order to increase strength, and this is usually unbleached sulphite or semi-bleached kraft. The standard basis weight for newsprint is 30 lb per 3000 ft2 (48.8 g/m2). Newsprint comes close to being a true commodity item. Most newsprint is the similar in terms of basis weight, brightness and price. The primary end users of newsprint are newspaper publishers, although some production goes to cormnercial printers. Uncoated Groundwood Uncoated groundwood papers (UCGW) are the next step in the value-added chain relative to newsprint. As with newsprint, the main furnish component is mechanical pulp, with chemical pulp being added to increase strength. The amount of chemical pulp used in the furnish depends upon the end product as well as the type of mechanical pulp used. The basis weight ranges from 18-40 1b per 500 sheets (24 x 36 in.) or 30-66 g/m2. UCGW papers are differentiated from newsprint with respect to printing properties and brightness, and are typically priced above standard newsprint. Some of the main UCGW grades are supercalendered papers (SC), directory papers and roto-news. Typical end uses for UCGW grades include free-standing inserts, telephone and other directories, Sunday news magazines, direct mail and commercial printing. Some of the trade names are: rotogravure (standard, premium, high brightness), offset (premium, high brightness), magazine (gravure, offset), paperback/book, directory (white, yellow) and computer. Coated Groundwood Coated groundwood papers are often referred to as lightweight coated (LWC). However, basis weights for coated groundwood can range from 32-50 lbs per 3,300 ft2. As with UCGW, the furnish for coated groundwood papers is primarily mechanical pulp with varying amounts of chemical pulp added for strength. The primary difference between coated and uncoated grades is the presence of a pigment layer which covers the base sheet. The main component of the coating is usually clay, however, calcium carbonate and titanium dioxide are also used in some formulations. Typically, the coating accounts for approximately 30% of the finished sheet by weight. Coated papers are broken down into 5 grades based on brightness and basis weight (#1 through #5). On the spectrum of coated printing grades, coated groundwood is #5, while #1 through #4 are primarily freesheet based. However, coated #4 can contain relatively high amounts of mechanical pulp. End uses for coated groundwood include magazines, Sunday news supplements, catalogs, newspaper inserts, directories, books and flyers. Uncoated Freesheet Uncoated freesheet papers (UCFS) are made primarily with chemical pulps and contain very little if any mechanical pulp. UCFS is produced in a wide range of basis weights and includes such end use products as personnel and business stationary, bond, ledger, envelopes, book paper, copy paper, laser printer papers, tablet paper, cigarette paper and base stock for products such as carbonless and thermal paper. In order to fill void spaces between fibers and improve the printing properties of the sheet, UCFS grades typically have filler contents of 10-15%. Fillers are usually comprised of clay, calcium carbonate and/or titanium dioxide, depending upon the desired sheet properties. If an alkaline paper making system is used, filler contents can reach levels of up to 30%. The use of calcium carbonate as a filler can also increase the permanence of the sheet, a quality that is becoming increasingly important to many publishers. Coated Freesheet Coated freesheet is the highest value-added grade of paper. As with uncoated freesheet, coated freesheet is made primarily with chemical pulp. The primary difference between the grades is the coating, which accounts for approximately 30% of the finished sheet weight. Coated freesheet can be either coated one side (ClS) or coated two side (C2S); coated two side accounts for approximately 90% of production. As previously discussed, coated papers are further defined on the basis of brightness and basis weight. Coated freesheet grades range from #1 through #4, with #1 being the brightest and highest quality coated paper. The bulk of coated freesheet production is classified as coated #3. Typical end uses for coated freesheet are high quality magazines, catalogs, advertising brochures, annual reports and various commercial printing applications. ClS papers are typically used for labels and other specialty products. |
2010年5月21日 星期五
[Packaging Material] CPE
一種聚丙烯(PP)與聚乙烯(PE)共聚合成的特殊薄膜
為改善PP和PE特性使用上的不足,使產品能多變化使用,研製出了新品:CPE。
CPE為PP與PE共聚合生產出的特殊薄膜,它有使PP、PE兩者皆可熱封的優良屬性,使產品的使用更具多元化。
CPE不但可對PP、PE熱封,更能有效提升熱封強度,也能改善以往PP不能承受低溫的現象。 CPE的透明度也達CPP的光澤度,改善了原PE的透明度。
CPE能帶給淋膜加工過程更大的方便性,因它很容易完成PP淋膜貼合。
CPE可謂是集PP、PE兩者優點之大成,能提供彩藝包材更多樣的選擇。
彩藝包材: LLDPE、CPP、CPE、CPPR、易撕膜、共擠多層尼龍膜、高阻隔拉深膜、積層膜、密著包裝膜、導電膜、抗靜電膜、夾鏈條(PP、PE)、各式包裝袋。
塑料包裝行業的發展趨向
| 包裝是塑料材料主要應用領域(特別是熱塑性材料),包裝業的需求和發展,直接改變或引導著塑料材料製造和加工技術的發展方向;從總體上講,塑料包裝材料和製品主要在三個方面面臨著巨大的壓力: 1.提高製品的性能,如增加材料和製品的透明性、耐熱性、機械強度和阻隔性等等。 2.來自環境保護方面的壓力。 3.降低成本的壓力。 需求總是帶動技術的進步,技術進步不斷創造質優價廉的奇蹟,而規模化生產而使成本大規模下降。 包裝製品是最主要應用領域 塑料製品以塑料薄膜(包括農用薄膜)、塑料絲及編織製品、塑料管材和日用塑料製品為主。 在塑料包裝領域,高密度聚乙烯薄膜的消耗量將繼續穩定增長;中空製品應用領域將向多品種、多樣化、專業化方向發展;多層共擠塑料軟管、藥品用塑料瓶以及各種中空容器產量將有較大增長;聚丙烯在注塑製品領域的消費比例將繼續提高,應用於薄膜製品的聚丙烯也會快速增長,但在編織製品應用領域中,聚丙烯消費比例將會明顯減少;聚氯乙烯製品將主要集中在建築領域,在包裝領域的應用將進一步減少;薄膜製品則將較多地由聚乙烯薄膜所取代;由於聚苯乙烯外帶飯包盒和其他發泡材料的「白色污染」問題,導致聚苯乙烯泡沫製品在包裝方面的用量會逐步萎縮。 常用塑料包裝材料的發展 PE、PP和PET是最常用的三種塑料包裝材料,其次為尼龍和PC、PVDC等材料。 1.PE 茂金屬乙烯是歐美國家發展的熱點,「茂金屬化聚烯烴」即是以茂金屬配位化合物為催化劑,進行烯烴聚合反應所製得的聚合物;茂金屬聚乙烯具有諸多優點,如好的光澤、高的熔體強度及薄膜穩定性等,適用於食品包裝領域,茂金屬塑料將直接衝擊PP、MDPE、LLDPE、彈性體等塑料巿場。 2.PP 新型PP牌號和改性PP材料層出不窮;由於很多改性PP具備了工程塑料的特性,因此,已經在相當多的領域取代了工程塑料;透明PP是目前發展較快的品種,在醫用製品和醫用包裝製品以及化妝品包裝等方面應用越來越多;BOPP瓶因為能夠耐受100℃以上的高溫,因此在功能飲料包裝上獲得廣泛應用;BOPP薄膜是發展最快的塑料薄膜品種,多層共擠BOPP薄膜是發展的趨向。 3.PET 由於PET耐高溫性較差,因此,與PET分子結構相似的PEN,PEN將大量進入食品包裝領域,引發PET之後的又一次包裝革命,PEN除耐熱性好外,還有比PET更優異的阻氣性和防紫外線性。 4.PC 因為開發出了飲水桶製造這一用途,使PC為工程塑料中需求量最大的品種之一。 5.PVDC、EVOH和尼龍 作為阻隔性塑料包裝材料,PVDC、EVOH和尼龍是包裝領域的複合材料,其中EVOH和尼龍薄膜大多用於替代鋁箔做阻隔層;PVDC主要用於塗覆,其次是製作煙膜,但在食品領域中的應用也日漸廣泛。 主要塑料包裝製品的發展趨向 塑料包裝製品可分為膜、袋、瓶、大型中空容器、淺盤和托盤等等,而又因用途和所用材料不同再區分: 1.保鮮膜將向功能化發展 塑料保鮮膜是使用量最大的膜類包裝物,能耐油脂、耐高溫,適用於微波加熱等功能的保鮮膜種類已越來越多,所用材料有PE、PVC和聚烯烴,而纏繞膜和熱收縮膜的發展情況也與之類似。 2.購物袋向降解塑料方向發展 背心式購物袋是最常使用的塑料包裝物,多以PE材料製成,由於購物袋使用量大,且不易回收、回收利用價值不大,是塑料購物袋回收處理比較困難的主要原因,因此,使用可生物降解的降解塑料是解決廢棄購物袋污染環境的理想方法;在堆肥條件下如何快速降解是技術發展的方向,而成本和保用期的性能是降解塑料能否大規模替代傳統購物袋的兩個重要因素。 3.高阻隔性軟包裝是發展趨勢 用於食品、藥品的高阻隔性軟包裝加速發展,作為主基材的BOPP薄膜,以多層共擠BOPP薄膜為主要發展,3層和5層膜為普遍;PET薄膜會因有更佳的阻隔性而在更多的領域代替BOPP薄膜;PVDC、尼龍和EVOH阻隔性薄膜的使用量將增加,而PVDC複合膜將在食品包裝領域更廣泛的應用。 |
| 4.塑料紡織袋將減少使用 塑料編織袋是將塑料薄膜(主要是聚丙烯)製成一定寬度的窄帶,或用熱拉伸法得到強度高、延伸率小的塑料扁帶,再將這些扁帶編織而成;塑料編織袋比塑料膜袋的強度高得多,且不易變形,耐衝擊性也好,同時由於編織袋表面有編織紋,提高了防滑性能,便於儲存時的堆碼;塑料編織袋用於糧食和水泥、化肥等產品的包裝,但防蟲、防濕性能差且環境污染大,故已減少使用。 5.水性及無溶劑粘合劑巿場巨大 在塑料複合材質中,水性粘合劑是發展的主軸,伴隨人們環保意識的增強,以及環保法規的更加嚴格,環保型水性及無溶劑粘合劑將會取代溶劑型粘合劑,成為主流產品。 6.飲料容器向低成本、高性能化發展 用於碳酸飲料和瓶裝水的PET瓶,因減輕克量的空間已有限,故以生產設備的高速化發展為主軸;飲料冷無菌灌裝使PET瓶再受重用,在普通PET瓶生產中使用回收料做芯層的多層瓶技術已成熟,但該技術對設備要求很高,使成本成為制約發展的因素;熱灌裝PET瓶的發展,集中在減輕克重和發展更多瓶型上;PC是製作5加侖飲水桶的主要材料,而PET製造的飲水桶同樣可以達到質量要求;BOPP瓶主要集中在部分需要高溫殺菌或巴氏殺菌的飲料上,如涼茶等;PE容器主要集中在大容量(如5升)瓶裝水上。 |
| 7.藥用和化妝品用塑料瓶 與飲料用注拉吹工藝生產的PET瓶不同,藥用和化妝品用瓶多為擠出生產的PE瓶,特別是洗滌用品瓶;透明瓶深受歡迎,不過,絕大部分洗髮用品的瓶子還是不透明的PE瓶,只是個別瓶蓋改用透明PP材質,高透明性的PP瓶和PET瓶將在洗髮護髮品包裝上獲得更多的應用;藥用塑料瓶多由PE和PP製成的,由於要考慮避光保存,PET瓶在這一領域的應用受到一定限制,不過總的趨勢是使用量越來越大。 8.中空容器向大型化、多層化發展 100公升以上的塑料中空容器普遍化,200公升的PE桶甚至可以達到Ⅱ類海運危規的要求,代替200公升閉口鋼桶;1噸以上的PE塑料桶成為石化、化工等行業液體包裝的主要形式;大型中空容器正在向雙層和多層共擠方向發展。 9.塑料盤、優酪乳和塑料托盤 塑料淺盤在快餐食品中經常使用,這類淺盤多由PP製成的;PP片材也是製造優酪乳包裝的主材質;不過,高檔優酪乳包裝有使用PS片材製造的趨向;塑料托盤質輕、耐水,不易受蟲害影響,美觀、整潔,可反覆使用,有利於露天作業和存放,與木質托盤相比,塑料托盤硬度及周轉使用率高過3-5倍,塑料托盤有單面型和雙面型,雙面型又分整體式和組裝式,而塑料托盤以注塑成型最多,擠出–中空吹塑成型法次之,擠出成型產品使用第三,真空成型吸塑成型使用第四。 |
乙烯/醋酸乙烯酯共聚合物(EVA)
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世界塑膠包裝産品發展趨勢
| 共聚複合包裝膜 歐美一些國家大量投資開發非極性、極性乙烯共聚物等,這將大大提高塑膜的拉伸和共擠性能,並提高透明度、密封強度、抗應力、抗龜裂,以及增強穩定性能、改善分子量布與擠塑流變性能。 如開發C4 -LLDPE,在高速注塑工藝中不損螺杆;HAOC6-LLDPE塑膠薄膜的韌性與硬性良好;C6-LLDPE拉伸共擠薄膜質量優良;C8-LLDPE薄膜韌性特佳;VLDPE(超低密度聚乙烯)薄膜平整度好,其樹脂的熔融溫度低,性能較好,流度性能好;C4-VLDPE/VLDPE(超低密度聚乙烯)適合作各種塑膠薄膜包裝。 在塑膠共擠工藝中混合LLDPE,可提高延伸性及抗穿透強度,LLDPE/LDPE可大大提高粘性與韌性,添加HAOC6-LLDPE和HAOC 8-LLDPE可促使流變性穩定,熱熔融不斷裂,塑膠薄膜製品不撕裂等等。 在注塑技術中,各國以VLDPE取代LLDPE、PP、EVA、PVC。 在擠塑、注塑、吹塑技術中,VLDPE將佔領醫藥、醫療、化妝品等的軟包裝市場,並進一步衝擊食品包裝領域。 國際專家們認爲:世界塑膠行業的發展重點在於對塑膠改性、塑膠製品的塗布技術、廢塑的快速生物降解,以及塑膠的回收再利用綜合技術。 如歐美一些廠商採取以線性乙烯-α烯共聚物與乙烯-醋酸乙烯共聚物混料/PA袋,適於包裝冰淇淋、乳脂類等食品。 多功能性複合薄膜 國外大量開發多功能性複合薄膜使其作用進一步細化,例如: 1.耐寒薄膜可耐-18℃、-20℃、-35℃低溫環境。 2.對PP作防潮處理製成的防潮薄膜,其系列產品可分爲防潮、防結露、防蒸冷、可調節水分等幾種類型。 3.防腐膜可包裝易腐、酸度大、甜度大的食品。 4.摩擦薄膜,穩定。 5.特種PE薄膜耐化學、耐腐蝕。 6.防蛀薄膜中添加了無異味防蟲劑。 7.以雙向拉伸尼龍66的耐熱薄膜取代雙向拉伸尼龍6包裝食品,其耐高溫達140℃。 8.保鮮膜密封性、防黴性好,無冷凝水結露。 9.水調節薄膜能吸收水果釋放的乙烯氣體。 10.新型專用食品包裝膜可提高食品包裝的保香性。 11.非結晶尼龍薄膜透明度類似玻璃。 12.高遮罩薄膜可保色、香味,營養指標及口感質量的穩定性。 13.金屬保護膜採用LDPE改性薄膜包裝液態産品,在低溫環境下可熱封;以PP合成紙提高該包裝的耐光性、耐寒性、耐熱性、耐水性、耐潮性、抗油脂性、抗酸性、抗鹼性以及抗衝擊性能等。 共擠包裝膜、片 由臺灣張恩工業公司開發的PP、PE、PVC變色塑膠片材,可製成各種器皿,打火機殼、口杯、酒杯以及吸管等塑膠製品,當杯內、機殼內溫度改變時,杯色與機殼色也隨之改變。 日本聚苯乙烯-紙公司開發推出遮罩性能優良的共擠發泡PE板材、PS板材,以及發泡PE模製品與PP模製品。 例如:以熔融指數爲7克/10份的PP和4%的PVC壬基苯基醚混合,製成厚7μm的OPP薄膜,其自粘性、耐熱性優良。 各類容器 國外推出一些塑膠新技術: |
| 1.歐洲市場推出以PVC透明卷材代替吹塑成型中空容器,可減重50%,在5~9層共擠薄膜工藝中,以回收塑膠作中間層,可降低成本費用,層厚由微處理反饋控制。 2.日本推出PET與PC共擠,不僅抗熱性、抗衝擊性、耐污染性、耐藥性均提高,同時價格也有所下降。 3.英國推出以特種PP樹脂注吹包裝瓶,可達到輕質、高強度、厚薄均勻、省原料的目的。以PP發泡收縮標套用於玻璃瓶,可抗90℃巴氏滅菌熱灌裝。 國外流行塑膠杯、複合杯(外層PSP、內層PP、蓋PS)包裝冷、熱飲料、酒、速食食品: 1.法國用P E瓶包裝果糖、酸奶。 2.德國用PC瓶包裝牛奶。 國外以多層模塑罐包裝食品、化妝品等,以複合罐包裝材料。 以 PE或與 EVA混合加工軟塑桶包裝桶飲料,適用於液體包裝。 國外周轉箱的發展趨勢是標準化、系列化、配套化、專用化,並注意防老化、防滑、堆高(定位)穩定、套疊化,加大R角,角部加強、薄壁輕質強度高。 國外大量配套發展適應各種標準及用途的專用塑蓋産品: 1.美國雷諾公司以鋁箔、紙、PE作瓶蓋。 2.歐洲用熱收縮膜蓋替代鋁封蓋。 3.日本推出耐高溫280℃的塗料瓶,具有六種系列化規格的CPI塗料鋁箔蓋,作爲乳酸飲料瓶用(鋁箔用高頻熱封,溫度達180℃~280℃)。 常用技術 國外對薄膜熱封常用技術有: 1.超聲波法:在對PP、PET、PE、 PVC、PA、塗紙、熱塑塗布鋁箔等的熱封時間<1秒,但對薄膜的透明度有影響。 2.鐳射法:主要適用對小面積的薄膜等進行熱封。 3.脈衝法:該法的熱封對向<1~3秒。在PP膜表面上塗布PVDC、氟醋酸,可改進PP膜的熱封性能。 國外流行的包裝技術有: 1.真空包(76cm/Hg),100℃殺菌,採用PE/PET、PA/EVA 等包裝熟食製品。 2.充氣包裝(CO2、O2、N2、乙醇氣)大量用於食品包裝。 3.氣調包裝用於包裝魚類製品。 4.貼體包裝用離子型薄膜取代PE、PVC膜。 5.保鮮包裝以微孔透氣薄膜、矽薄膜等包裝具有呼吸規律的新鮮水果蔬菜。 6.滅菌包裝以高溫短時、超高溫暫態加熱殺滅污染菌,巴氏滅菌包裝飲料。 7.無菌包裝滅污染菌包裝果汁等飲料。 8.殺菌包裝採用離子型薄膜,以環氧乙烯氣體消毒,包裝醫療器械。 9.泡罩包裝主要作藥片包裝。 10.防銹包裝,在薄膜中加防銹劑包裝精密儀器。 11.拉伸裹包主要用單元裝(託盤、托板等)的裹包包裝。 12.熱收縮包裝主要作小型零部件包裝。 13.防黴包裝在薄膜中加防黴劑包裝織物。 14.壓縮包裝主要包裝質輕的棉衣、羽絨等的包裝。 |
| 15.防震緩衝包裝採用軟質聚氨、PVC,發泡 PE、PP、LLDPE、離子型聚合物等包裝材料等。 |