01How kraft paper is made
Wood chips, usually with a high share of softwood like pine or spruce, are cooked under heat and pressure in a solution of sodium hydroxide and sodium sulfide (white liquor). That dissolves the lignin that binds wood fibers together while leaving the long cellulose fibers mostly intact. The name comes from the German word for strength.
The pulp is washed and screened. For brown kraft it is left unbleached; for white kraft it goes through bleaching stages. Pulp is then diluted, spread on a moving wire on the paper machine, drained, pressed and dried over heated cylinders. A large single dryer cylinder gives machine glazed (MG) kraft with one smooth side. Mills recover and reuse most of the cooking chemicals, which is part of why the process dominates.
Recycled kraft is made by repulping used corrugated boxes and kraft bags. Recycling shortens fibers each time, so recycled kraft is generally weaker and a little rougher than virgin at the same weight, and its color varies more from lot to lot.
02Virgin vs recycled kraft
| Virgin kraft | Recycled kraft | |
|---|---|---|
| Fiber | Fresh wood pulp, long fibers | Repulped boxes and bags, shorter fibers |
| Strength | Higher tear and burst strength | Lower; may need higher GSM for the same job |
| Color | Even, warm brown | Greyer or mottled, varies by lot |
| Print quality | Better ink holdout on smooth grades | Ink soaks in more; specks are common |
| Price | Higher | Lower |
| Claim | FSC or PEFC certified virgin fiber | Recycled content, often FSC Recycled |
In corrugated board, you will see virgin liners called kraftliner and recycled liners called testliner. For a box that has to survive parcel networks, a kraft outer liner is the safer pick. For inner packaging and wrap, recycled kraft is usually fine.
03Kraft in mailers, bags and tissue
- Paper mailers: kraft envelopes or bags with a peel-and-seal strip, often with a second strip for returns. Padded versions use honeycomb kraft or recycled paper fiber instead of bubble wrap.
- Shopping bags: flat or twisted paper handles on 80 to 120 GSM kraft is a common starting point; heavier or reinforced bases for heavy goods.
- Wrapping and void fill: lighter MG kraft or crinkled kraft, often recycled.
- Tissue: most tissue paper is not kraft. Packaging tissue is a light MG sulfite or recycled sheet around 17 to 30 GSM. Kraft-colored tissue exists, but it is a different, much lighter paper.
- Rigid boxes and folding cartons: kraft is used as a wrap or face sheet for a natural look; see rigid boxes.
04Printing on brown kraft
Most inks are translucent, so on brown stock every color mixes with the brown underneath. Light colors disappear, whites go beige and brand colors shift darker and muddier. Plan the artwork for the brown, not for a white screen.
- Use dark, high-contrast colors: black, navy, deep green and deep red work best.
- Keep it to one or two spot colors on flexo; full color photos rarely look good on brown kraft.
- For white or light colors, ask for an opaque white ink or an underlay; it costs more and is not always crisp.
- Hot foil and screen printing sit on top of the paper and give brighter results.
- If you need full color, use white kraft or a white top-liner and keep the brown inside.
- Always ask for a printed proof on the actual stock before bulk.
05Pros and cons
- Strong for its weight, especially virgin kraft
- Widely recyclable and compostable when uncoated
- Cheap, easy to source and available in stock sizes
- Natural, low-key look that reads as sustainable without extra design
- Works across bags, mailers, wrap, labels, tape and box liners
- Brown stock limits print color and detail
- Weakens when wet unless coated, and coatings can hurt recyclability
- Recycled kraft is weaker and varies in color lot to lot
- Paper mailers offer less protection than poly mailers for heavy or fragile items
- Heavier and bulkier than plastic mailers, which can raise shipping costs
06Typical uses and price
- Paper shopping bags and gift bags
- Paper and padded mailers for ecommerce
- Wrapping paper and void fill
- Outer liners of corrugated shipping boxes
- Labels, hangtags and paper tape
- Food wrap and bakery bags (with food-safe grades)
Price tier: Budget. Kraft is one of the cheapest packaging papers. Recycled grades are usually cheapest, virgin and bleached white kraft cost more, and custom printing, coatings and handles add cost per unit. Freight is a big share of paper packaging cost because it is heavy and bulky.
07How to spec it with a factory
Packaging factories quote on paper grade, weight, size, print and finishing. Spell out each in your tech pack or dieline brief so quotes are comparable.
| No. | Field | What to write |
|---|---|---|
| 01 | Paper grade | Virgin or recycled kraft, unbleached (brown) or bleached (white), MG or machine finished |
| 02 | Weight | GSM with tolerance, e.g. 100 GSM plus or minus 5% |
| 03 | Format and size | Bag, mailer, roll or sheet; finished dimensions, gusset and flap sizes; attach dieline |
| 04 | Closures and handles | Peel-and-seal strip (and second return strip), twisted or flat paper handles |
| 05 | Method (flexo, offset, screen, foil), number of colors, Pantone references, coverage | |
| 06 | Coatings | None, water-based, or PE; state if it must remain curbside recyclable |
| 07 | Strength | Load test for bags, burst or tear requirement for mailers |
| 08 | Certification | FSC or PEFC chain of custody, and the exact label you plan to print |
| 09 | Packing | Units per carton, carton dimensions and palletizing |
Certifications and marks
- FSC
- Chain of custody for responsibly sourced or recycled fiber. Every company in the chain, including the printer, needs certification to put the FSC label on your packaging.
- PEFC
- Alternative forest certification, common in Europe. Same chain of custody idea as FSC.
- SFI
- Forest certification common in North America for paper and board.
From the factory floor
- Get a printed sample on the real stock. Colors on brown kraft never match the screen.
- Drop test and load test mailers and bags with your heaviest product before ordering bulk.
- If you want an FSC logo, confirm the printer holds FSC chain of custody; the paper mill alone is not enough.
- Recycled kraft varies in shade; ask for a lot tolerance if color consistency matters.
- Stock sizes with a printed sticker or stamp are far cheaper and lower MOQ than fully custom printed items.
08Kraft paper mailers vs poly mailers
| Kraft paper mailer | Poly mailer | |
|---|---|---|
| Recyclability | Curbside recyclable when uncoated | Usually store drop-off only |
| Water resistance | Low unless coated | High |
| Tear and puncture | Good, but lower | High |
| Weight and bulk | Heavier | Lighter, flatter |
| Limited on brown | Full color easy | |
| Cost | Usually higher per unit | Usually lower per unit |
09Kraft paper vs white paper (bleached)
White kraft is still kraft, just bleached; it prints much better and costs more. Brown kraft hides scuffs and reads as natural. Many brands use brown on the outside of a box and white inside, or print on white kraft for color-heavy designs. For premium unboxing see rigid boxes.
10FAQ
Q01Is kraft paper recyclable?
Yes, uncoated kraft paper is widely accepted in curbside recycling and is compostable. Plastic coatings, foil laminates and heavy glue can make it harder to recycle.
Q02Why is kraft paper brown?
Because it is unbleached. The brown comes from residual lignin and natural wood color left in the pulp. Bleached kraft is white.
Q03What GSM kraft paper should I use for bags?
Roughly 80 to 120 GSM is common for retail shopping bags. Lighter weights suit small or lightweight items; heavy goods need higher GSM or reinforced bases.
Q04Is kraft paper waterproof?
No. It absorbs water and weakens when wet. Coated or laminated kraft resists moisture but may be harder to recycle.
Q05Can you print in color on kraft paper?
Yes, but colors shift darker because the brown shows through. Dark spot colors work best; use white ink, foil or white kraft for light colors and full color.