Ứng dụng nano ZnO trong mực in offset thạch bản kháng khuẩn

NHIN RH THE GIOI

ONG DUNG NANO zno TRONG MUC IN DFFSET

THACH BAN KHANG KHUAN •

Ngay nay, in offset thach ban la ky thuat chu lire trong nganh in, cho^phepjn thanh

pham vfii so' lifdng ifin ma vin flam bao chat lifofng. Tuy nhign, vS'n fle nhiim khuSn

trong qua trinh in khien cho ky thuat nay vin con nhffng han che', flgc bigt trong viec

ffng dung vao cac san pham bao bl thyc pham va dUtfc pha'm. Gin flSy, cac nha nghien

c(?u flg'n tif Khoa Ceng nghg in thufic Vifn Nghien cffu c6ng nghe va khoa hgc ve mau

sic (Iran) da thanh cfing trong viec tgo ra mgt logi mUc in co khd nang khang khuan

cao, dua trgn viec kg't hop mye in offset truyen the'ng vfii cac hat nano ZnO, htfa hen co

t hi giai quyg't va'n di ntiiim khuan cua qua trinh in mOt each higu qua hern.

Ky tliuat in offset thach ban

In offset thach ban la mdt trong nhflng phfldng

phap chu Iflc cua nganh in, dfla tren nguyen ly ddn

giin: pha dau chfla mUc in va pha nfldc khdng dfnh

vao nhau. Trong ky thuat nay, khudn in cd hinh ve

bang nhij tfldng dfldc cudn len mdt try trong may in,

sau dd nfldc va mfle in lan Iflpt dugc lan trdn khudn.

Nfldc chi dfnh vio nhflng chd trdng cua khudn, khdng

dfnh vao khu vflc cd nhu tfldng cua hinh ve, ngflde Igi

mfle in ehl dfnh vao phan hinh ve, khdng dfnh vao khu

vflc da dinh nfldc. Tiep dd, try in nay dfldc lan trdn mpt

tru ddi didn bang cao su de hinh ve tham mfle dfnh

vao tru cao su (offset), ddng thdi nUdc dUdc dp chay

ra ngoai. Cudi eung giay ddpc lan tren try cao su de

in hinh. Mfle in cua phfldng phap in offset thach ban

thfldng la mdt hdn hdp nhao phflc tap, trong dd bdt

mau hflu cd dflpc phan tin vao hon hpp dung mdi pha

ddu v i nhfla alkyd [1]. Khi muc in dflpc phu len tren

giay, mgt qua trinh tich pha dac trdng se diln ra: eac

phan tfl nhua tfl trung hpp de lien ket vdi nhau, tach

ra khoi pha dung mdi, tfl dd giup ket dinh cac hat bdt

mau. Nhd nhflng die diem nay, in thach ban offset

the hien flu diem vUdt trdi so vdi cie ky thuat in truyen

thdng khac nhfl tiet kiem ve kinh phf, phu hpp vdi nhu

cau in thanh pham sd Iflpng Idn.

Hien nay, ky thuat in offset dfldc ap dung ddi vdi rat

nhieu ddi tfldng in an khac nhau nhfl: bio va tap chf

giay, td rdi, bao bi va sach. Tuy nhien trong mgt vai

nganh dac thu nhfl in bao bi dong gdi thfle pham va

dddc pham, van de nhilm khuan trong qui trinh in quy

md Idn ludn la trd ngai dang k l ddi vdi chat Ifldng sin

pham. Chfnh vi viy, nghien eflu cac tie nhan khang

khuan, cy thi la cae idp phCi eau true nano vdi tinh chdt

khang khuan dang trd thanh mdt hudng mdi thu hut rat

nhieu sfl quan tam eua cdng ddng khoa hpc [2,3].

Tinh Ghat khang khuan cua ZnO

Kem oxid (ZnO) tfl lau da dflgc biet ddn nhfl mdt vat

lieu than thien mdi trfldng, ddc tfnh thi'p va dgc bidtco

hogt tfnh khang khuan eao [4]. Ngoai ra, nhieu nghign

cflu gan day eung cho thi'y, cie hgt nano ZnO la tac

nhan chd'ng vi tao hieu qua khi dfldc dung lam ldp phO

ldn be mat eac vat lieu xay dflng va vii vdc [2]. Hdri

nfla, vide dfla ZnO vio cau true mgng vit lieu polymer

cdn lam tang dp ben cd ly eua vat lidu composite do

hinh thanh cae tuong tic manh gifla hgt nano vd cd va

cic nhdm chflc hflu cd polymer [5].

Nhieu nghidn cflu cho thay, cac hgt nano ZnO vdi

kich thfldc tfl 10 den 50 nm the hien hogt tfnh khang

khuan cao hdn bdt ZnO dgng khdi (kfch thfldc hat

khoang 2 pm). Nano ZnO cd thi loai bo hieu qua cac vi

khuan Staphylococcus aureus va Escherichia coll [6].

Ngfldi ta cho rang, hoat tfnh khing khuan cCia ZnO mOt

phan den tfl tfldng tac tTnh dien eua oxit vdi bd mat t^

bao eua vi khuan, san sinh ra H^O^ [7], phan khac ddn

tfl kha nang hinh thanh cae tilu phin oxy hoat ddng

cd the oxy hda thanh te bao, khien cho vi khuIn bj tidu

diet [8], Mac du la tie nhan ddc tinh ddi vdi vi khuIn,

ZnO gan nhU khdng cd anh hUdng ddi vdi sflc kh6e

eon ngfldi khi tiep xue bdn ngoai ed the. Do dd ZnO

30 TapcHKHOAHM gdis

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