View source for Chemical wood pulp

[[File:100_Chem. softwood_conif adj.jpg|thumb|Chemical hardwood (non-coniferous)]]
== Description ==

Paper pulp made from chemically treated wood fibers. Chemical pulp is produced by treating debarked, ground wood or chips with strong solutions to dissolve the lignin and hemicellulose. The undissolved cellulose fibers are washed, rinsed, sometimes bleached, then used to produce paper. The three main types of solutions used to make chemical pulp are:

- alkaline: [[sodium sulfide]] followed by [[sodium hydroxide|caustic soda]] solution ([[kraft process]]), 

- alkaline: caustic soda ([[soda process]]), 

- acid: [[calcium bisulfite|acid bisulfite]] ([[sulfite process]]).

[[File:100_Chem. softwood_conif_pol adj.jpg|thumb|Chemical hardwood (non-coniferous)]]

== Synonyms and Related Terms ==

chemical pulp; woodfree pulp

== Other Properties ==

Produces a pale blue-violet to red violet response to iodine-zinc chloride solution. [[Graff "C" stain]] can be used to distinguish types of chemical pulping and bleaching.

== Additional Images ==

<gallery>
File:99_Chem. softwood_conif adj.jpg|Chemical softwood (coniferous)
File:99_Chem. softwood_conif_pol adj.jpg|Chemical softwood (coniferous)
File:SWBS puget 10x label.jpg|Chemical softwood stained with Graff "C" Stain
File:SUBK 10x2 label.jpg|Chemical softwood stained with Graff "C" Stain
File:SBA 40x pinoidpitslabel.jpg|Chemical softwood stained with Graff "C" Stain
File:Redoak vessels 10x.jpg|Chemical hardwood stained with Graff "C" stain
File:Elm 40x.jpg|Chemical hardwood stained with Graff "C" stain
Sycamore 40x.jpg|Chemical hardwood stained with Graff "C" stain
Redgum 10x.jpg|Chemical hardwood stained with Graff "C" stain
Yellowpoplar 40x.jpg|Chemical hardwood stained with Graff "C" stain
</gallery>

== Authority ==

* ''Encyclopedia Britannica'', http://www.britannica.com  Comment: "Paper Pulp." Encyclopædia Britannica. 2003.  11 Sep, 2003  .

* Random House, ''Webster's Encyclopedic Unabridged Dictionary of the English Language'', Grammercy Book, New York, 1997

* G.S.Brady, ''Materials Handbook'', McGraw-Hill Book Co., New York, 1971  Comment: p. 574

* ''The Dictionary of Paper'', American Paper Institute, New York, Fourth Edition, 1980

* E.J.LaBarre, ''Dictionary and Encyclopedia of Paper and Paper-making'', Swets & Zeitlinger, Amsterdam, 1969

* Boise Cascade Paper Group, ''The Paper Handbook'', Boise Cascade, Portland OR, 1989

* J. H. Graff "Color Atlas for Fiber Identification" The Institute of Paper Chemistry, Appleton, WI, 1940.

* Walter Rantanen. "Fiber ID Course." Integrated Paper Services. June 2013. Lecture.

* Matt Roberts, Don Etherington, ''Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology'', U.S. Government Printing Office, Washington DC, 1982

* TAPPI Official Standard T401 om-08. ''Fiber analysis of paper and paperboard''. 2008. http://www.tappi.org/Downloads/Test-Methods/UNTITLED-0104T401pdf.aspx

* Silvie Turner, ''Which Paper?'', Design Press, New York, 1991

[[Category:Materials database]]